Australian Beer Prices set to Double Due to Global Warming?

Earlier this week Nature Plants published a new paper Decreases in global beer supply due to extreme drought and heat

The Scientific American has an article “Trouble Brewing? Climate Change Closes In on Beer Drinkers” with the sub-title “Increasing droughts and heat waves could have a devastating effect on barley stocks—and beer prices”. The Daily Mail headlines with “Worst news ever! Australian beer prices are set to DOUBLE because of global warming“. All those climate deniers in Australia have denied future generations the ability to down a few cold beers with their barbecued steaks tofu salads.

This research should be taken seriously, as it is by a crack team of experts across a number of disciplines and Universities. Said, Steven J Davis of University of California at Irvine,

The world is facing many life-threatening impacts of climate change, so people having to spend a bit more to drink beer may seem trivial by comparison. But … not having a cool pint at the end of an increasingly common hot day just adds insult to injury.

Liking the odd beer or three I am really concerned about this prospect, so I rented the paper for 48 hours to check it out. What a sensation it is. Here a few impressions.

Layers of Models

From the Introduction, there were a series of models used.

  1. Created an extreme events severity index for barley based on extremes in historical data for 1981-2010.
  2. Plugged this into five different Earth Systems models for the period 2010-2099. Use this against different RCP scenarios, the most extreme of which shows over 5 times the warming of the 1981-2010 period. What is more severe climate events are a non-linear function of temperature rise.
  3. Then model the impact of these severe weather events on crop yields in 34 World Regions using a “process-based crop model”.
  4. (W)e examine the effects of the resulting barley supply shocks on the supply and price of beer in each region using a global general equilibrium model (Global Trade Analysis Project model, GTAP).
  5. Finally, we compare the impacts of extreme events with the impact of changes in mean climate and test the sensitivity of our results to key sources of uncertainty, including extreme events of different severities, technology and parameter settings in the economic model.

What I found odd was they made no allowance for increasing demand for beer over a 90 year period, despite mentioning in the second sentence that

(G)lobal demand for resource-intensive animal products (meat and dairy) processed foods and alcoholic beverages will continue to grow with rising incomes.

Extreme events – severity and frequency

As stated in point 2, the paper uses different RCP scenarios. These featured prominently in the IPCC AR5 of 2013 and 2014. They go from RCP2.6, which is the most aggressive mitigation scenario, through to RCP 8.5 the non-policy scenario which projected around 4.5C of warming from 1850-1870 through to 2100, or about 3.8C of warming from 2010 to 2090.

Figure 1 has two charts. On the left it shows that extreme events will increase intensity with temperature. RCP2.6 will do very little, but RCP8.5 would result by the end of the century with events 6 times as intense today. Problem is that for up to 1.5C there appears to be no noticeable change what so ever.  That is about the same amount of warming the world has experienced from 1850-2010 per HADCRUT4 there will be no change. Beyond that things take off. How the models empirically project well beyond known experience for a completely different scenario defeats me. It could be largely based on their modelling assumptions, which is in turn strongly tainted by their beliefs in CAGW. There is no reality check that it is the models that their models are not falling apart, or reliant on arbitrary non-linear parameters.

The right hand chart shows that extreme events are porjected to increase in frequency as well. Under RCP 2.6 ~ 4% chance of an extreme event, rising to ~ 31% under RCP 8.5. Again, there is an issue of projecting well beyond any known range.

Fig 2 average barley yield shocks during extreme events

The paper assumes that the current geographical distribution and area of barley cultivation is maintained. They have modelled in 2099, from the 1981-2010 a gridded average yield change with 0.5O x 0.5O resolution to create four colorful world maps representing each of the four RCP emissions scenarios. At the equator, each grid is about 56 x 56 km for an area of 3100 km2, or 1200 square miles. Of course, nearer the poles the area diminishes significantly. This is quite a fine level of detail for projections based on 30 years of data to radically different circumstances 90 years in the future. The results show. Map a) is for RCP 8.5. On average yields are projected to be 17% down. As Paul Homewood showed in a post on the 17th, this projected yield fall should be put in the context of a doubling of yields per hectare since the 1960s.

This increase in productivity has often solely ascribed to the improvements in seed varieties (see Norman Borlaug), mechanization and use of fertilizers. These have undoubtably have had a large parts to play in this productivity improvement. But also important is that agriculture has become more intensive. Forty years ago it was clear that there was a distinction between the intensive farming of Western Europe and the extensive farming of the North American prairies and the Russian steppes. It was not due to better soils or climate in Western Europe. This difference can be staggering. In the Soviet Union about 30% of agricultural output came from around 1% of the available land. These were the plots that workers on the state and collective farms could produce their own food and sell surplus in the local markets.

Looking at chart a in Figure 2, there are wide variations about this average global decrease of 17%.

In North America Montana and North Dakota have areas where barley shocks during extreme years will lead to mean yield changes over 90% higher normal, and the areas around have >50% higher than normal. But go less than 1000 km North into Canada to the Calgary/Saskatoon area and there are small decreases in yields.

In Eastern Bolivia – the part due North of Paraguay – there is the biggest patch of > 50% reductions in the world. Yet 500-1000 km away there is a North-South strip (probably just 56km wide) with less than a 5% change.

There is a similar picture in Russia. On the Kazakhstani border, there are areas of > 50% increases, but in a thinly populated band further North and West, going from around Kirov to Southern Finland is where there are massive decreases in yields.

Why, over the course of decades, would those with increasing yields not increase output, and those with decreasing yields not switch to something else defeats me. After all, if overall yields are decreasing due to frequent extreme weather events, the farmers would be losing money, and those farmers do well when overall yields are down will be making extraordinary profits.

A Weird Economic Assumption

Building up to looking at costs, their is a strange assumption.

(A)nalysing the relative changes in shares of barley use, we find that in most case barley-to-beer shares shrink more than barley-to-livestock shares, showing that food commodities (in this case, animals fed on barley) will be prioritized over luxuries such as beer during extreme events years.

My knowledge of farming and beer is limited, but I believe that cattle can be fed on other things than barley. For instance grass, silage, and sugar beet. Yet, beers require precise quantities of barley and hops of certain grades.

Further, cattle feed is a large part of the cost of a kilo of beef or a litre of milk. But it takes around 250-400g of malted barley to produce a litre of beer. The current wholesale price of malted barley is about £215 a tonne or 5.4 to 8.6p a litre. About cheapest 4% alcohol lager I can find in a local supermarket is £3.29 for 10 x 250ml bottles, or £1.32 a litre. Take off 20% VAT and excise duty leaves 30p a litre for raw materials, manufacturing costs, packaging, manufacturer’s margin, transportation, supermarket’s overhead and supermarket’s margin. For comparison four pints (2.276 litres) of fresh milk costs £1.09 in the same supermarket, working out at 48p a litre. This carries no excise duty or VAT. It might have greater costs due to refrigeration, but I would suggest it costs more to produce, and that feed is far more than 5p a litre.

I know that for a reasonable 0.5 litre bottle of ale it is £1.29 to £1.80 a bottle in the supermarkets I shop in, but it is the cheapest that will likely suffer the biggest percentage rise from increase in raw material prices. Due to taxation and other costs, large changes in raw material prices will have very little impact on final retail costs. Even less so in pubs where a British pint (568ml) varies from the £4 to £7 a litre equivalent.

That is, the assumption is the opposite of what would happen in a free market. In the face of a shortage, farmers will substitute barley for other forms of cattle feed, whilst beer manufacturers will absorb the extra cost.

Disparity in Costs between Countries

The most bizarre claim in the article in contained in the central column of Figure 4, which looks at the projected increases in the cost of a 500 ml bottle of beer in US dollars. Chart h shows this for the most extreme RCP 8.5 model.

I was very surprised that a global general equilibrium model would come up with such huge disparities in costs after 90 years. After all, my understanding of these models used utility-maximizing consumers, profit-maximizing producers, perfect information and instantaneous adjustment. Clearly there is something very wrong with this model. So I decided to compare where I live in the UK with neighbouring Ireland.

In the UK and Ireland there are similar high taxes on beer, with Ireland being slightly more. Both countries have lots of branches of the massive discount chain. They also have some products on their website aldi.co.uk and aldi.ie.  In Ireland a 500 ml can of Sainte Etienne Lager is €1.09 or €2.18 a litre or £1.92 a litre. In the UK it is £2.59 for 4 x 440ml cans or £1.59 a litre. The lager is about 21% more in Ireland. But the tax difference should only be about 15% on a 5% beer (Saint Etienne is 4.8%). Aldi are not making bigger profits in Ireland, they just may have higher costs in Ireland, or lesser margins on other items. It is also comparing a single can against a multipack. So pro-rata the £1.80 ($2.35) bottle of beer in the UK would be about $2.70 in Ireland. Under the RCP 8.5 scenario, the models predict the bottle of beer to rise by $1.90 in the UK and $4.84 in Ireland. Strip out the excise duty and VAT and the price differential goes from zero to $2.20.

Now suppose you were a small beer manufacturer in England, Wales or Scotland. If beer was selling for $2.20 more in Ireland than in the UK, would you not want to stick 20,000 bottles in a container and ship it to Dublin?

If the researchers really understood the global brewing industry, they would realize that there are major brands sold across the world. Many are brewed across in a number of countries to the same recipe. It is the barley that is shipped to the brewery, where equipment and techniques are identical with those in other parts of the world. This researchers seem to have failed to get away from their computer models to conduct field work in a few local bars.

What can be learnt from this?

When making projections well outside of any known range, the results must be sense-checked. Clearly, although the researchers have used an economic model they have not understood the basics of economics. People are not dumb  automatons waiting for some official to tell them to change their patterns of behavior in response to changing circumstances. They notice changes in the world around them and respond to it. A few seize the opportunities presented and can become quite wealthy as a result. Farmers have been astute enough to note mounting losses and change how and what they produce. There is also competition from regions. For example, in the 1960s Brazil produced over half the world’s coffee. The major region for production in Brazil was centered around Londrina in the North-East of Parana state. Despite straddling the Tropic of Capricorn, every few years their would be a spring-time frost which would destroy most of the crop. By the 1990s most of the production had moved north to Minas Gerais, well out of the frost belt. The rich fertile soils around Londrina are now used for other crops, such as soya, cassava and mangoes. It was not out of human design that the movement occurred, but simply that the farmers in Minas Gerais could make bumper profits in the frost years.

The publication of this article shows a problem of peer review. Nature Plants is basically a biology journal. Reviewers are not likely to have specialist skills in climate models or economic theory, though those selected should have experience in agricultural models. If peer review is literally that, it will fail anyway in an inter-disciplinary subject, where the participants do not have a general grounding in all the disciplines. In this paper it is not just economics, but knowledge of product costing as well. It is academic superiors from the specialisms that are required for review, not inter-disciplinary peers.

Kevin Marshall

 

IPCC SR1.5 – Notes on Calculations and Assumptions

Given that my previous post was about failing to reconcile the emissions estimates for 1.5°C and 2.0°C of warming in the IPCC fifth assessment report (AR5), I was intrigued to see how the new IPCC “special report on the impacts of global warming of 1.5 °C above pre-industrial levels” would fare. However, that will have to wait for another post, as first there are some “refinements” from AR5 in how results are obtained. From my analysis they would appear that key figures on temperatures and climate sensitivities are highly contrived.

Isn’t 1.5°C of warming already built in? 

Chapter 1 Page 24

Expert judgement based on the available evidence (including model simulations, radiative forcing and climate sensitivity) suggests that if all anthropogenic emissions were reduced to zero immediately, any further warming beyond the 1°C already experienced would likely be less than 0.5°C over the next two to three decades, and also likely less than 0.5°C on a century timescale.

This basically states that if all emissions were stopped now there is more than a 50% chance that warming would not exceed 1.5°C. But using previous assumptions 1.5°C should be already be built in. 

If ECS = 3.0 (as in AR5) then that implies the net effect of all GHGs and all aerosols is less than 396 ppm, despite CO2 on its own in September 2018 being 405.5 ppm (1.6°C of eventual warming). Further, in 2011 the impact of all GHGs combined was equivalent to 430 ppm, or an extra 40 ppm more than CO2 on its own. On that basis we are at the around 445 ppm or fractionally about the 2.0°C warming level. However, in AR5 it was assumed (based on vague estimates) that the negative human impacts of aerosols exactly offset the addition of other GHGs (e.g. methane) so that only CO2 is considered. Even then based on ECS = 3.0 without further emissions 1.5°C will be eventually reached.

But ECS has been lowered.

From Chapter 1 Annex Page 11

…Equilibrium Climate Sensitivity (ECS) of 2.7°C and Transient Climate Response (TCR) of 1.6°C and other parameters as given in Millar et al. (2017).

This raises the CO2-eq level to achieve 1.5°C of warming by 15-16 ppm from 396ppm and the CO2-eq level to achieve 2.0°C by 23-24 ppm from 444 ppm. Mauna Loa CO2 levels in September averaged 405.5 ppm. With ECS = 2.7 this is equivalent to just 1.44°C of eventual warming compared to 1.60°C  when ECS = 3.0. What is more significant is that if ECS were 2.8 eventual warming of 1.50°C would be in the pipeline sometime before the end of the year. ECS = 2.7 is the highest ECS that us currently compatible with the statement made above if CO2 alone is taken into account. Consider this in the light of 2013 AR5 WG1 SPM, which stated on page 16

Equilibrium climate sensitivity is likely in the range 1.5°C to 4.5°C

And in a footnote on the same page.

No best estimate for equilibrium climate sensitivity can now be given because of a lack of agreement on values across assessed lines of evidence and studies.

 In AR5 they chose ECS = 3.0 as it was in the middle of the range. A range unchanged since the Charney Report of 1979. I am not aware of any that establishes ECS is a range that would justify ECS = 2.7 that is not contradicted by other research. For instance Lewis and Curry 2018 gives a median estimate for ECS of 1.66.

Transient Climate Response (TCR)

But how does the Transient Climate Response (TCR) of 1.6°C fit into this? Some context can be had from the very start of the Summary for Policy-Makers SPM-4

A1.1. Reflecting the long-term warming trend since pre-industrial times, observed global mean surface temperature (GMST) for the decade 2006–2015 was 0.87°C (likely between 0.75°C and 0.99°C)

With TCR = 1.6°C for a doubling of CO2 levels what is the warming generated from a rise in CO2 levels from 280 to 400.83 ppm? That is a rise in CO2 levels from pre-industrial times to the average level in 2015. I calculate it to be 0.83°C. Make TCR = 1.7°C and that increases to 0.88°C. It is effectively assuming that both 100% of the rise in average temperatures in over 150 years is due to CO2 alone (consistent with AR5), and there has been no movement whatsoever from the short-term Transient Climate Response to the long-term Equilibrium Climate Sensitivity. However, if TCR is a variable figure derived from a calculation from revealed warming and CO2 rise, it becomes meaningless nonsense unless you can clearly demonstrate the other assumptions are robust. That is (1) 100% of past warming was due to human emissions (2) the impact of GHGs other than CO2 are effectively cancelled out by aerosols etc. (3) natural factors are net zero (4) the average temperature data anomaly is without any systematic biases. For instance, when measured CO2 levels were about 390ppm, the AR5 WG3 SPM stated in the last sentence on page 8

For comparison, the CO2-eq concentration in 2011 is estimated to be 430 ppm (uncertainty range 340 to 520 ppm)

It seems a pretty shaky foundation to the assumption that negative impact of aerosols (with uncertainties) will offset the combined impact of other GHG increases.

Summary and Concluding Comments

On the estimates of climate sensitivity, it appears to be set so that the IPCC can still claim that if emissions stopped tomorrow then there would be a greater than 50% chance of 1.5°C warming never been exceeded. The ECS value of 2.7°C is set at the maximum value, given the assumptions. But ceteris paribus, this will not hold if

  • One waits 3 years and CO2 levels continue increasing at a rate of the last few years.
  • ECS is slightly higher but still well within the accepted range of estimates. Indeed if ECS = 3.0, as in AR5 and AR4 in 2007, then 1.5C of warming was exceeded 5 years ago.
  • The impact of all GHGs together is slightly more than the offsetting impacts of other aerosols.
  • 0.06°C, or more, of the observed rise on temperature since 1850 is not due to GHG emissions.

Then there is the Transient Climate Response (TCR) which appears to be little more than taking the historical temperature change, assuming all of is down to human GHG emissions, and calculating a figure. Including rises in CO2 a century or more ago is hardly transient.

Based on my calculations, the results are highly contrived. They appear as a very fine balance between getting the maximum values for human-caused warming possible and not admitting that 1.5°C or even 2°C is already passed. There is a huge combination of empirical assumptions that are as equally valid as the ones used in the SR1.5 that go one way or the other. Rather than being a robust case, empirically it is highly improbable one.

Finally there is a conundrum here. I have calculated that if ECS = 2.7 and the starting level of CO2 is 280 ppm, then in round numbers, 1.5°C of warming results from CO2 levels of 412 ppm and 2.0°C of warming results from CO2 levels of 468 ppm. With CO2 levels in September 2018 at 406 ppm for 2.0°C of warming requires a rise in CO2 ten times greater than for 1.5°C of warming. So how can the IPCC claim that it is only about twice the amount of emissions? In my previous post I could not find an explanation, even though the emissions numbers reconciled with both past data and future emissions to generate 2.0°C of warming given certain assumptions. In the next I hope to provide an answer, which fits the figures quite closely, but looks pretty embarrassing.

Kevin Marshall

Why can’t I reconcile the emissions to achieve 1.5C or 2C of Warming?

Introduction

At heart I am beancounter. That is when presented with figures I like to understand how they are derived. When it comes to the claims about the quantity of GHG emissions that are required to exceed 2°C of warming I cannot get even close, unless by making some a series of  assumptions, some of which are far from being robust. Applying the same set of assumptions I cannot derive emissions consistent with restraining warming to 1.5°C

Further the combined impact of all the assumptions is to create a storyline that appears to me only as empirically as valid as an infinite number of other storylines. This includes a large number of plausible scenarios where much greater emissions can be emitted before 2°C of warming is reached, or where (based on alternative assumptions) plausible scenarios even 2°C of irreversible warming is already in the pipeline.  

Maybe an expert climate scientist will clearly show the errors of this climate sceptic, and use it as a means to convince the doubters of climate science.

What I will attempt here is something extremely unconventional in the world of climate. That is I will try to state all the assumptions made by highlighting them clearly. Further, I will show my calculations and give clear references, so that anyone can easily follow the arguments.

Note – this is a long post. The key points are contained in the Conclusions.

The aim of constraining warming to 1.5 or 2°C

The Paris Climate Agreement was brought about by the UNFCCC. On their website they state.

The Paris Agreement central aim is to strengthen the global response to the threat of climate change by keeping a global temperature rise this century well below 2 degrees Celsius above pre-industrial levels and to pursue efforts to limit the temperature increase even further to 1.5 degrees Celsius. 

The Paris Agreement states in Article 2

1. This Agreement, in enhancing the implementation of the Convention, including its objective, aims to strengthen the global response to the threat of climate change, in the context of sustainable development and efforts to eradicate
poverty, including by:

(a) Holding the increase in the global average temperature to well below 2°C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5°C above pre-industrial levels, recognizing that this would significantly reduce the risks and impacts of climate change;

Translating this aim into mitigation policy requires quantification of global emissions targets. The UNEP Emissions Gap Report 2017 has a graphic showing estimates of emissions before 1.5°C or 2°C warming levels is breached.

Figure 1 : Figure 3.1 from the UNEP Emissions Gap Report 2017

The emissions are of all greenhouse gas emissions, expressed in billions of tonnes of CO2 equivalents. From 2010, the quantity of emissions before the either 1.5°C or 2°C is breached are respectively about 600 GtCO2e and 1000 GtCO2e. It is these two figures that I cannot reconcile when using the same  assumptions to calculate both figures. My failure to reconcile is not just a minor difference. Rather, on the same assumptions that 1000 GtCO2e can be emitted before 2°C is breached, 1.5°C is already in the pipeline. In establishing the problems I encounter I will clearly endeavor to clearly state the assumptions made and look at a number of examples.

 Initial assumptions

1 A doubling of CO2 will eventually lead to 3°C of rise in global average temperatures.

This despite the 2013 AR5 WG1 SPM stating on page 16

Equilibrium climate sensitivity is likely in the range 1.5°C to 4.5°C

And stating in a footnote on the same page.

No best estimate for equilibrium climate sensitivity can now be given because of a lack of agreement on values across assessed lines of evidence and studies.

2 Achieving full equilibrium climate sensitivity (ECS) takes many decades.

This implies that at any point in the last few years, or any year in the future there will be warming in progress (WIP).

3 Including other greenhouse gases adds to warming impact of CO2.

Empirically, the IPCC’s Fifth Assessment Report based its calculations on 2010 when CO2 levels were 390 ppm. The AR5 WG3 SPM states in the last sentence on page 8

For comparison, the CO2-eq concentration in 2011 is estimated to be 430 ppm (uncertainty range 340 to 520 ppm)

As with climate sensitivity, the assumption is the middle of an estimated range. In this case over one fifth of the range has the full impact of GHGs being less than the impact of CO2 on its own.

4 All the rise in global average temperature since the 1800s is due to rise in GHGs. 

5 An increase in GHG levels will eventually lead to warming unless action is taken to remove those GHGs from the atmosphere, generating negative emissions. 

These are restrictive assumptions made for ease of calculations.

Some calculations

First a calculation to derive the CO2 levels commensurate with 2°C of warming. I urge readers to replicate these for themselves.
From a Skeptical Science post by Dana1981 (Dana Nuccitelli) “Pre-1940 Warming Causes and Logic” I obtained a simple equation for a change in average temperature T for a given change in CO2 levels.

ΔTCO2 = λ x 5.35 x ln(B/A)
Where A = CO2 level in year A (expressed in parts per million), and B = CO2 level in year B.
I use λ = .809, so that if B = 2A, ΔTCO2 = 3.00

Pre-industrial CO2 levels were 280ppm. 3°C of warming is generated by CO2 levels of 560 ppm, and 2°C of warming is when CO2 levels reach 444 ppm.

From the Mauna Loa CO2 data, average CO2 levels averaged 407 ppm in 2017. Given the assumption (3) and further assuming the impact of other GHGs is unchanged, 2°C of warming would have been surpassed in around 2016 when CO2 levels averaged 404 ppm. The actual rise in global average temperatures is from HADCRUT4 is about half that amount, hence the assumption that the impact of a rise in CO2 takes an inordinately long time for the actual warming to reveal itself. Even with the assumption that 100% of the warming since around 1800 is due to the increase in GHG levels warming in progress (WIP) is about the same as revealed warming. Yet the Sks article argues that some of the early twentieth century warming was due to other than the rise in GHG levels.

This is the crux of the reconciliation problem. From this initial calculation and based on the assumptions, the 2°C warming threshold has recently been breached, and by the same assumptions 1.5°C was likely breached in the 1990s. There are a lot of assumptions here, so I could have missed something or made an error. Below I go into some key examples that verify this initial conclusion. Then I look at how, by introducing a new assumption it is claimed that 2°C warming is not yet reached.

100 Months and Counting Campaign 2008

Trust, yet verify has a post We are Doomed!

This tracks through the Wayback Machine to look at the now defunct 100monthsandcounting.org campaign, sponsored by the left-wing New Economics Foundation. The archived “Technical Note” states that the 100 months was from August 2008, making the end date November 2016. The choice of 100 months turns out to be spot-on with the actual data for CO2 levels; the central estimate of the CO2 equivalent of all GHG emissions by the IPCC in 2014 based on 2010 GHG levels (and assuming other GHGs are not impacted); and the central estimate for Equilibrium Climate Sensitivity (ECS) used by the IPCC. That is, take 430 ppm CO2e, and at 14 ppm for 2°C of warming.
Maybe that was just a fluke or they were they giving a completely misleading forecast? The 100 Months and Counting Campaign was definitely not agreeing with the UNEP Emissions GAP Report 2017 in making the claim. But were they correctly interpreting what the climate consensus was saying at the time?

The 2006 Stern Review

The “Stern Review: The Economics of Climate Change” (archived access here) that was commissioned to provide benefit-cost justification for what became the Climate Change Act 2008. From the Summary of Conclusions

The costs of stabilising the climate are significant but manageable; delay would be dangerous and much more costly.

The risks of the worst impacts of climate change can be substantially reduced if greenhouse gas levels in the atmosphere can be stabilised between 450 and 550ppm CO2 equivalent (CO2e). The current level is 430ppm CO2e today, and it is rising at more than 2ppm each year. Stabilisation in this range would require emissions to be at least 25% below current levels by 2050, and perhaps much more.

Ultimately, stabilisation – at whatever level – requires that annual emissions be brought down to more than 80% below current levels. This is a major challenge, but sustained long-term action can achieve it at costs that are low in comparison to the risks of inaction. Central estimates of the annual costs of achieving stabilisation between 500 and 550ppm CO2e are around 1% of global GDP, if we start to take strong action now.

If we take assumption 1 that a doubling of CO2 levels will eventually lead to 3.0°C of warming and from a base CO2 level of 280ppm, then the Stern Review is saying that the worst impacts can be avoided if temperature rise is constrained to 2.1 – 2.9°C, but only in the range of 2.5 to 2.9°C does the mitigation cost estimate of 1% of GDP apply in 2006. It is not difficult to see why constraining warming to 2°C or lower would not be net beneficial. With GHG levels already at 430ppm CO2e, and CO2 levels rising at over 2ppm per annum, the 2°C of warming level of 444ppm (or the rounded 450ppm) would have been exceeded well before any global reductions could be achieved.

There is a curiosity in the figures. When the Stern Review was published in 2006 estimated GHG levels were 430ppm CO2e, as against CO2 levels for 2006 of 382ppm. The IPCC AR5 states

For comparison, the CO2-eq concentration in 2011 is estimated to be 430 ppm (uncertainty range 340 to 520 ppm)

In 2011, when CO2 levels averaged 10ppm higher than in 2006 at 392ppm, estimated GHG levels were the same. This is a good example of why one should take note of uncertainty ranges.

IPCC AR4 Report Synthesis Report Table 5.1

A year before the 100 Months and Counting campaign The IPCC produced its Fourth Climate Synthesis Report. The 2007 Synthesis Report on Page 67 (pdf) there is table 5.1 of emissions scenarios.

Figure 2 : Table 5.1. IPCC AR4 Synthesis Report Page 67 – Without Footnotes

I inputted the various CO2-eq concentrations into my amended version of Dana Nuccitelli’s magic equation and compared to the calculation warming in Table 5.1

Figure 3 : Magic Equation calculations of warming compared to Table 5.1. IPCC AR4 Synthesis Report

My calculations of warming are the same as that of the IPCC to one decimal place except for the last two calculations. Why are there these rounding differences? From a little fiddling in Excel, it would appear to me that the IPCC got the warming results from a doubling of 3 when calculating to two decimal places, whilst my version of the formula is to four decimal places.

Note the following

  • That other GHGs are translatable into CO2 equivalents. Once translated other GHGs they can be treated as if they were CO2.
  • There is no time period in this table. The 100 Months and Counting Campaign merely punched in existing numbers and made a forecast ahead of the GHG levels that would reach the 2°C of warming.
  • No mention of a 1.5°C warming scenario. If constraining warming to 1.5°C did not seem credible in 2007, which should it be credible in 2014 or 2017, when CO2 levels are higher?

IPCC AR5 Report Highest Level Summary

I believe that the underlying estimates of emissions to achieve the 1.5°C or 2°C  of warming used by the UNFCCC and UNEP come from the UNIPCC Fifth Climate Assessment Report (AR5), published in 2013/4. At this stage I introduce an couple of empirical assumptions from IPCC AR5.

6 Cut-off year for historical data is 2010 when CO2 levels were 390 ppm (compared to 280 ppm in pre-industrial times) and global average temperatures were about 0.8°C above pre-industrial times.

Using the magic equation above, and the 390 ppm CO2 levels, there is around 1.4°C of warming due from CO2. Given 0.8°C of revealed warming to 2010, the residual “warming-in-progress” was 0.6°C.

The highest level of summary in AR5 is a Presentation to summarize the central findings of the Summary for Policymakers of the Synthesis Report, which in turn brings together the three Working Group Assessment Reports. This Presentation can be found at the bottom right of the IPCC AR5 Synthesis Report webpage. Slide 33 of 35 (reproduced below as Figure 4) gives the key policy point. 1000 GtCO2 of emissions from 2011 onwards will lead to 2°C. This is very approximate but concurs with the UNEP emissions gap report.

Figure 4 : Slide 33 of 35 of the AR5 Synthesis Report Presentation.

Now for some calculations.

1900 GtCO2 raised CO2 levels by 110 ppm (390-110). 1 ppm = 17.3 GtCO2

1000 GtCO2 will raise CO2 levels by 60 ppm (450-390).  1 ppm = 16.7 GtCO2

Given the obvious roundings of the emissions figures, the numbers fall out quite nicely.

Last year I divided CDIAC CO2 emissions (from the Global Carbon Project) by Mauna Loa CO2 annual mean growth rates (data) to produce the following.

Figure 5 : CDIAC CO2 emissions estimates (multiplied by 3.664 to convert from carbon units to CO2 units) divided by Mauna Loa CO2 annual mean growth rates in ppm.

17GtCO2 for a 1ppm rise is about right for the last 50 years.

To raise CO2 levels from 390 to 450 ppm needs about 17 x (450-390) = 1020 GtCO2. Slide 33 is a good approximation of the CO2 emissions to raise CO2 levels by 60 ppm.

But there are issues

  • If ECS = 3.00, and 17 GtCO2 of emissions to raise CO2 levels by 1 ppm, then it is only 918 (17*54) GtCO2 to achieve 2°C of warming. Alternatively, in future if there are assume 1000 GtCO2 to achieve 2°C  of warming it will take 18.5 GtCO2 to raise CO2 levels by 1 ppm, as against 17 GtCO2 in the past. It is only by using 450 ppm as commensurate with 2°C of warming that past and future stacks up.
  • If ECS = 3,  from CO2 alone 1.5°C would be achieved at 396 ppm or a further 100 GtCO2 of emissions. This CO2 level was passed in 2013 or 2014.
  • The calculation falls apart if other GHGs are included.  Emissions are assumed equivalent to 430 ppm at 2011. Therefore with all GHGs considered the 2°C warming would be achieved with 238 GtCO2e of emissions ((444-430)*17) and the 1.5°C of warming was likely passed in the 1990s.
  • If actual warming since pre-industrial times to 2010 was 0.8°C, ECS = 3, and the rise in all GHG levels was equivalent to a rise in CO2 from 280 to 430 ppm, then the residual “warming-in-progress” (WIP) was just over 1°C. That it is the WIP exceeds the total revealed warming in well over a century. If there is a short-term temperature response is half or more of the value of full ECS, it would imply even the nineteenth century emissions are yet to have the full impact on global average temperatures.

What justification is there for effectively disregarding the impact of other greenhouse emissions when it was not done previously?

This offset is to be found in section C – The Drivers of Climate Change – in AR5 WG1 SPM . In particular the breakdown, with uncertainties, in table SPM.5. Another story is how AR5 reached the very same conclusion as AR4 WG1 SPM page 4 on the impact of negative anthropogenic forcings but with a different methodology, hugely different estimates of aerosols along with very different uncertainty bands. Further, these historical estimates are only for the period 1951-2010, whilst the starting date for 1.5°C or 2°C is 1850.

From this a further assumption is made when considering AR5.

7 The estimated historical impact of other GHG emissions (Methane, Nitrous Oxide…) has been effectively offset by the cooling impacts of aerosols and precusors. It is assumed that this will carry forward into the future.

UNEP Emissions Gap Report 2014

Figure 1 above is figure 3.1 from the UNEP Emissions GAP Report 2017. The equivalent report from 2014 puts this 1000 GtCO2 of emissions in a clearer context. First a quotation with two accompanying footnotes.

As noted by the IPCC, scientists have determined that an increase in global temperature is proportional to the build-up of long-lasting greenhouse gases in the atmosphere, especially carbon dioxide. Based on this finding, they have estimated the maximum amount of carbon dioxide that could be emitted over time to the atmosphere and still stay within the 2 °C limit. This is called the carbon dioxide emissions budget because, if the world stays within this budget, it should be possible to stay within the 2 °C global warming limit. In the hypothetical case that carbon dioxide was the only human-made greenhouse gas, the IPCC estimated a total carbon dioxide budget of about 3 670 gigatonnes of carbon dioxide (Gt CO2 ) for a likely chance3 of staying within the 2 °C limit . Since emissions began rapidly growing in the late 19th century, the world has already emitted around 1 900 Gt CO2 and so has used up a large part of this budget. Moreover, human activities also result in emissions of a variety of other substances that have an impact on global warming and these substances also reduce the total available budget to about 2 900 Gt CO2 . This leaves less than about 1 000 Gt CO2 to “spend” in the future4 .

3 A likely chance denotes a greater than 66 per cent chance, as specified by the IPCC.

4 The Working Group III contribution to the IPCC AR5 reports that scenarios in its category which is consistent with limiting warming to below 2 °C have carbon dioxide budgets between 2011 and 2100 of about 630-1 180 GtCO2

The numbers do not fit, unless the impact of other GHGs are ignored. As found from slide 33, there is 2900 GtCO2 to raise atmospheric CO2 levels by 170 ppm, of which 1900 GtC02 has been emitted already. The additional marginal impact of other historical greenhouse gases of 770 GtCO2 is ignored. If those GHG emissions were part of historical emissions as the statement implies, then that marginal impact would be equivalent to an additional 45 ppm (770/17) on top of the 390 ppm CO2 level. That is not far off the IPCC estimated CO2-eq concentration in 2011 of 430 ppm (uncertainty range 340 to 520 ppm). But by the same measure 3670 GTCO2e would increase CO2 levels by 216 ppm (3670/17) from 280 to 496 ppm. With ECS = 3, this would eventually lead to a temperature increase of almost 2.5°C.

Figure 1 above is figure 3.1 from the UNEP Emissions GAP Report 2017. The equivalent report from the 2014 report ES.1

Figure 6 : From the UNEP Emissions Gap Report 2014 showing two emissions pathways to constrain warming to 2°C by 2100.

Note that this graphic goes through to 2100; only uses the CO2 emissions; does not have quantities; and only looks at constraining temperatures to 2°C.  To achieve the target requires a period of negative emissions at the end of the century.

A new assumption is thus required to achieve emissions targets.

8 Sufficient to achieve the 1.5°C or 2°C warming targets likely requires many years of net negative emissions at the end of the century.

A Lower Level Perspective from AR5

A simple pie chart does not seem to make sense. Maybe my conclusions are contradicted by the more detailed scenarios? The next level of detail is to be found in table SPM.1 on page 22 of the AR5 Synthesis Report – Summary for Policymakers.

Figure 7 : Table SPM.1 on Page 22 of AR5 Synthesis Report SPM, without notes. Also found as Table 3.1 on Page 83 of AR5 Synthesis Report 

The comment for <430 ppm (the level of 2010) is "Only a limited number of individual model studies have explored levels below 430 ppm CO2-eq. ” Footnote j reads

In these scenarios, global CO2-eq emissions in 2050 are between 70 to 95% below 2010 emissions, and they are between 110 to 120% below 2010 emissions in 2100.

That is, net global emissions are negative in 2100. Not something mentioned in the Paris Agreement, which only has pledges through to 2030. It is consistent with the UNEP Emissions GAP report 2014 Table ES.1. The statement does not refer to a particular level below 430 ppm CO2-eq, which equates to 1.86°C. So how is 1.5°C of warming not impossible without massive negative emissions? In over 600 words of notes there is no indication. For that you need to go to the footnotes to the far more detailed Table 6.3 AR5 WG3 Chapter 6 (Assessing Transformation Pathways – pdf) Page 431. Footnote 7 (Bold mine)

Temperature change is reported for the year 2100, which is not directly comparable to the equilibrium warming reported in WGIII AR4 (see Table 3.5; see also Section 6.3.2). For the 2100 temperature estimates, the transient climate response (TCR) is the most relevant system property.  The assumed 90% range of the TCR for MAGICC is 1.2–2.6 °C (median 1.8 °C). This compares to the 90% range of TCR between 1.2–2.4 °C for CMIP5 (WGI Section 9.7) and an assessed likely range of 1–2.5 °C from multiple lines of evidence reported in the WGI AR5 (Box 12.2 in Section 12.5).

The major reason that 1.5°C of warming is not impossible (but still more unlikely than likely) for CO2 equivalent levels that should produce 2°C+ of warming being around for decades is because the full warming impact takes so long to filter through.  Further, Table 6.3 puts Peak CO2-eq levels for 1.5-1.7°C scenarios at 465-530 ppm, or eventual warming of 2.2 to 2.8°C. Climate WIP is the difference. But in 2018 WIP might be larger than all the revealed warming in since 1870, and certainly since the mid-1970s.

Within AR5 when talking about constraining warming to 1.5°C or 2.0°C it is only the warming which is estimated to be revealed in 2100. There is no indication of how much warming in progress (WIP) there is in 2100 under the various scenarios, therefore I cannot reconcile back the figures. However, for GHG  would appear that the 1.5°C figure relies upon a period of over 100 years for impact of GHGs on warming failing to come through as (even netting off other GHGs with the negative impact of aerosols) by 2100 CO2 levels would have been above 400 ppm for over 85 years, and for most of those significantly above that level.

Conclusions

The original aim of this post was to reconcile the emissions sufficient to prevent 1.5°C or 2°C of warming being exceeded through some calculations based on a series of restrictive assumptions.

  • ECS = 3.0°C, despite the IPCC being a best estimate across different studies. The range is 1.5°C to 4.5°C.
  • All the temperature rise since the 1800s is assumed due to rises in GHGs. There is evidence that this might not be the case.
  • Other GHGs are netted off against aerosols and precursors. Given that “CO2-eq concentration in 2011 is estimated to be 430 ppm (uncertainty range 340 to 520 ppm)” when CO2 levels were around 390 ppm, this assumption is far from robust.
  • Achieving full equilibrium takes many decades. So long in fact that the warming-in-progress (WIP) may currently exceed all the revealed warming in over 150 years, even based on the assumption that all of that revealed historical warming is due to rises in GHG levels.

Even with these assumptions, keeping warming within 1.5°C or 2°C seems to require two assumptions that were not recognized a few years ago. First is to assume net negative global emissions for many years at the end of the century. Second is to talk about projected warming in 2100 rather than warming as a resultant on achieving full ECS.

The whole exercise appears to rest upon a pile of assumptions. Amending the assumptions means one way means admitting that 1.5°C or 2°C of warming is already in the pipeline, or the other way means admitting climate sensitivity is much lower. Yet there appears to be a very large range of empirical assumptions to chose from there could be there are a very large number of scenarios that are as equally valid as the ones used in the UNEP Emissions Gap Report 2017.

Kevin Marshall

Increasing Extreme Weather Events?

Over at Cliscep, Ben Pile posted Misleading Figures Behind the New Climate Economy. Ben looked at the figures behind the recent New Climate Economy Report from the Global Commission on the Economy and Climate, which claims to be

… a major international initiative to examine how countries can achieve economic growth while dealing with the risks posed by climate change. The Commission comprises former heads of government and finance ministers and leaders in the fields of economics and business, and was commissioned by seven countries – Colombia, Ethiopia, Indonesia, Norway, South Korea, Sweden and the United Kingdom – as an independent initiative to report to the international community.

In this post I will briefly look at Figure 1 from the report, re-posted by Ben Pile.

Fig 1 – Global Occurrences of Extreme Weather Events from New Economy Climate Report

Clearly these graphs seem to demonstrate a rapidly worsening situation. However, I am also aware of a report a few years ago authored by Indur Goklany, and published by The Global Warming Policy Foundation  – GLOBAL DEATH TOLL FROM EXTREME WEATHER EVENTS DECLINING

Figure 2 : From Goklany 2010 – Global Death and Death Rates Due to Extreme Weather Events, 1900–2008. Source: Goklany (2009), based on EM-DAT (2009), McEvedy and Jones (1978), and WRI (2009).

 

Note that The International Disaster Database is EM-DAT. The website is here to check. Clearly these show two very different pictures of events. The climate consensus (or climate alarmist) position is that climate change is getting much worse. The climate sceptic (or climate denier) position is that is that human-caused climate change is somewhat exaggerated. Is one side outright lying, or is their some truth in both sides?

Indur Goklany recognizes the issue in his report. His Figure 2, I reproduce as figure 3.

Figure 3: Average Number of Extreme Weather Events per Year by Decade, 1900–2008.  Source: Goklany (2009), based on EM-DAT (2009).

I am from a management accounting background. That means that I check my figures. This evening I registered at the EM-DAT website and downloaded the figures to verify the data. The website looks at all sorts of disaster information, not just climate information. It collates

Figure 4 : No of Climatic Occurrences per decade from EM-DAT. Note that 2010-2016 pro rata is similar to 2000-2009

The updated figures through to 2016 show that pro rata, in the current decade occurrences if climate-related events as similar to the last decade. If one is concerned about the human impacts, deaths are more relevant.

Figure 5 : No of Climatic Deaths per decade from EM-DAT. Note that 2010-2016 pro rata is similar to 2000-2009

This shows unprecedented flood deaths in the 1930s. Of the 163218 flood deaths in 6 occurrences, 142000 were due to a flood in China in 1935. Wikipedia’s Ten deadliest natural disasters since 1900 lists at No.8 1935 Yangtze river flood, with 145000 dead. At No.1 is 1931 China floods with 1-4 million deaths. EM-DAT has not registered this disaster.

The decade 1970-1979 was extreme for deaths from storms. 300000 deaths were due to a Bangladesh storm in 1970. Wikipedia’s Ten deadliest natural disasters since 1900 lists at No.2 1970 Bhola cyclone, with ≥500,000.

The decade 1990-1999 had a high flood death toll. Bangladesh 1991 stands out with 138987 dead. Wikipedia No.10 is 1991 Bangladesh cyclone with 138866 dead.

In the decade 2000-2009 EM-DAT records the Myanmar Storm of 2008 with 138366 dead. If Wikipedia had a top 11 deadliest natural disasters since 1900, then Cyclone Nargis of 2 May 2008 could have made the list. From the BBC, with 200000 estimated dead, it would have qualified. But from the Red Cross 84500 Cyclone Nargis may have not made the top 20.

This leaves a clear issue of data. The International Disaster Database will accept occurrences of disasters according to clear criteria. For the past 20-30 years disasters have been clearly recorded. The build-up of a tropical cylone / hurricane is monitored by satellites and film crews are on hand to televise across the world pictures of damaged buildings, dead bodies, and victims lamenting the loss of homes. As I write Hurricane Florence is about to pound the Carolinas, and evacuations have been ordered. The Bhola Cyclone of 1970 was no doubt more ferocious and impacted on a far greater number of people. But the primary reason for the extreme deaths in 1970 Bangladesh was lack of warning and a lack of evacuation places. Even in the Wizard of Oz, based on 1930s United States, in a Tornado most families had a storm cellar. In the extreme poverty of 1970 Bangladesh there was nothing. Now, after decades of moderate growth and some rudimentary warning systems, it is unlikely that a similar storm would cause even a tenth of the death toll.

Even more significant, is that even if (as I hope) Hurricane Florence causes no deaths and limited property damage, it will be sufficiently documented to qualify for an entry on the International Disaster Database. But the quality of evidence for the 1931 China Floods, occurring in a civil war between the Communists and the Kuomintang forces, would be insufficient to qualify for entry. This is why one must be circumspect in interpreting this sort of data over periods when the quality and availability of data varies significantly. The issue I have is not with EM-DAT, but those who misinterpret the data for an ideological purpose.

Kevin Marshall

Excess Deaths from 2018 Summer Heatwaves

Last month I looked at the claims by the UK Environmental Audit Committee warning of 7,000 heat-related deaths in the 2050s, finding it was the result a making a number of untenable assumptions. Even if the forecast turned out to be true, cold deaths would still be more than five times the hot deaths. With the hottest summer since 1976, it is not surprising that there have been efforts to show there are excess heat deaths.

On the 6th August, The Daily Express headlined UK heatwave turns KILLER: 1,000 more people die this summer than average as temps soar.

Deaths were up in all seven weeks from June 2 to July 20, which saw temperatures reach as high as 95F (35C).

A total of 955 people more than the average have died in England and Wales since the summer began, according to the Office for National Statistics (ONS).

On the 3rd August the Guardian posted Deaths rose 650 above average during UK heatwave – with older people most at risk.

The height of the heatwave was from 25 June to 9 July, according to the Met Office, a run of 15 consecutive days with temperatures above 28C. The deaths registered during the weeks covering this period were 663 higher than the average for the same weeks over the previous five years, a Guardian analysis of data from the Office of National Statistics shows.

Note the Guardian’s lower figure was from a shorter time period.

I like to put figures in context, so I looked up the ONS Dataset:Deaths registered monthly in England and Wales

There they have detailed data from 2006 to July 2018. Estimating the excess deaths from these figures needs some estimation of other factors. However, some indication of excess deaths can be gleaned from taking the variation from the average. In July 2018 there were 40,624 recorded deaths, as against an average of 38,987 deaths in July in the years 2006-2018. There were therefore 1,637 deaths more than average. I have charted the variation from average for each year.

There were above average deaths in July 2018, but there similar figure in the same month in 2014 and 2015. Maybe the mean July temperatures from the Central England Temperature Record show a similar variation?

Not really. July 2006 had high mean temperatures and average deaths, whilst 2015 had low mean temperatures and higher than average deaths.

There is a further element to consider. Every month so far this year has had higher than average deaths. Below I have graphed the variation by month.

January is many times more significant than July. In the first seven months of this year there were 30,000 more deaths recorded than the January-July average for 2006 to 2018. But is this primarily due to the cold start to the year followed by a barbecue summer? Looking at the variations from average 300,000 deaths for the period January to July period, it does not seem this is the case.

Looking at individual months, if extreme temperatures alone caused excess deaths I would expect an even bigger peak during in January 2010 when there was record cold than this year. In January 2010 there were 48363 recorded deaths, against 64157 in January 2018 and a 2006-2018 average of 52383. Clearly there is a large seasonal element to deaths as the average for July is 39091, or three-quarters of the January level. But discerning the temperature related element is extremely tricky, and any estimates of excess deaths to a precise number should be treated with extreme caution.

Kevin Marshall

Milk loss yields down to heat stress

Last week, Wattupwiththat post “Climate Study: British Children Won’t Know What Milk Tastes Like”. Whilst I greatly admire Anthony Watts, I think this title entirely misses the point.
It refers to an article at the Conservation “How climate change will affect dairy cows and milk production in the UK – new study” by two authors at Aberystwyth University, West Wales. This in turn is a write up of a Plos One article published in May “Spatially explicit estimation of heat stress-related impacts of climate change on the milk production of dairy cows in the United Kingdom“. The reason I disagree is that even with very restrictive assumptions, this paper shows that even with large changes in temperature, the unmitigated costs of climate change are very small. The authors actually give some financial figures. Referring to the 2190s the PLOS One abstract ends:-

In the absence of mitigation measures, estimated heat stress-related annual income loss for this region by the end of this century may reach £13.4M in average years and £33.8M in extreme years.

The introduction states

The value of UK milk production is around £4.6 billion per year, approximately 18% of gross agricultural economic output.

For the UK on average Annual Milk Loss (AML) due to heat stress is projected to rise from 40 kg/cow to over 170 kg/cow. Based on current yields it is from 0.5% to 1.8% in average years. The most extreme region is the south-east where average AML is projected to rise from 80 kg/cow to over 320 kg/cow. That is from 1% to 4.2% in average years. That is, if UK dairy farmers totally ignore the issue of heat stress for decades the industry could see average revenue losses from heat stress rise on average from £23m to £85m. The financial losses are based on constant prices of £0.30 per litre.

With modeled estimates over very long periods, it is worth checking the assumptions.

Price per liter of milk

The profits are based upon a constant price of £0.30 a liter. But prices can fluctuate according to market conditions. Data on annual average prices paid is available from AHDB Dairy, ” a levy-funded, not-for-profit organisation working on behalf of Britain’s dairy farmers.” Each month, since 2004, there are reported the annual average prices paid by dairies over a certain size available here. That is 35-55 in any one month. I have taken the minimum and maximum prices for reported in June each year and shown in Figure 1.

Even annual average milk prices fluctuate depending on market conditions. If milk production is reduced in summer months due to an unusual heat wave causing heat stress, ceteris paribus, prices will rise. It could be that a short-term reduction in supply would increase average farming profits if prices are not fixed. It is certainly not valid to assume fixed prices over many decades.

Dumb farmers

From the section in the paper “Milk loss estimation methods

It was assumed that temperature and relative humidity were the same for all systems, and that no mitigation practices were implemented. We also assumed that cattle were not significantly different from the current UK breed types, even though breeding for heat stress tolerance is one of the proposed measures to mitigate effects of climate change on dairy farms.

This paper is looking at over 70 years in the future. If heatwaves were increasing, so yields falling and cattle were suffering, is it valid to assume that farmers will ignore the problem? Would they not learn from areas with more extreme heatwaves in summer elsewhere such as in central Europe? After all in the last 70 years (since the late 1940s) breeding has increased milk yields phenomenally (from AHDB data, milk yields per cow have increased 15% from 2001/2 to 2016/7 alone) so a bit of breeding to cope with heatwaves should be a minor issue.

The Conversation article states the implausible assumptions in a concluding point.

These predictions assume that nothing is done to mitigate the problems of heat stress. But there are many parts of the world that are already much hotter than the UK where milk is produced, and much is known about what can be done to protect the welfare of the animals and minimise economic losses from heat stress. These range from simple adaptations, such as the providing shade, to installing fans and water misting systems.

Cattle breeding for increased heat tolerance is another potential, which could be beneficial for maintaining pasture-based systems. In addition, changing the location of farming operations is another practice used to address economic challenges worldwide.

What is not recognized here is that farmers in a competitive market have to adapt in the light of new information to stay in business. That is the authors are telling farmers what they will be fully aware of to the extent that their farms conform to the average. Effectively assuming people and dumb, then telling them obvious, is hardly going to get those people to take on board one’s viewpoints.

Certainty of global warming

The Conversation article states

Using 11 different climate projection models, and 18 different milk production models, we estimated potential milk loss from UK dairy cows as climate conditions change during the 21st century. Given this information, our final climate projection analysis suggests that average ambient temperatures in the UK will increase by up to about 3.5℃ by the end of the century.

This warming is consistent with the IPCC global average warming projections using RCP8.5 non-mitigation policy scenario. There are two alternative, indeed opposite, perspectives that might lead rational decision-makers to think this quantity of warming is less than certain.

First, the mainstream media, where the message being put out is that the Paris Climate Agreement can constrain global warming to 2°C or 1.5°C above the levels of the mid-nineteenth century. With around 1°C of warming already if it is still possible to constrain additional global warming to 0.5°C, why should one assume that 3.5°C of warming for the UK is more than a remote possibility in planning?

Second, one could look at the track record of global warming projections from the climate models. The real global warming scare kicked-off with James Hansen’s testimony to Congress in 1988. Despite actual greenhouse gas emissions being closely aligned with rapid warming, actual global warming has been most closely aligned with the assumption of the impact of GHG emissions being eliminated by 2000. Now, if farming decision-makers want to still believe that emissions are the major driver of global warming, they can find plenty of excuses for the failure linked from here. But, rational decision-makers tend to look at the track record and thus take consistent decision-makers with more than a pinch of salt.

Planning horizons

The Conversation article concludes

(W)e estimate that by 2100, heat stress-related annual income losses of average size dairy farms in the most affected regions may vary between £2,000-£6,000 and £6,000-£14,000 (in today’s value), in average and extreme years respectively. Armed with these figures, farmers need to begin planning for a hotter UK using cheaper, longer-term options such as planting trees or installing shaded areas.

This compares to the current the UK average annual dairy farm business income of £80,000 according to the PLOS One article.

There are two sides to investment decision-making. There are potential benefits – in this case avoidance of profit loss – netted against the potential benefits. ADHB Dairy gives some figures for the average herd size in the UK. In 2017 it averaged 146 cows, almost double the 75 cows in 1996. In South East England, that is potentially £41-£96 a cow, if the average herd size there is same as the UK average. If the costs rose in a linear fashion, that would be around 50p to just over a pound a year per cow in the most extreme affected region. But the PLOS One article states that costs will rise exponentially. That means there will be no business justification for evening considering heat stress for the next few decades.

For that investment to be worthwhile, it would require the annual cost of mitigating heat stress to be less than these amounts. Most crucially, rational decision-makers apply some sort of NPV calculation to investments. This includes a discount rate. If most of the costs are to be incurred decades from now – beyond the working lives of the current generation of farmers – then there is no rational reason to take into account heat stress even if global warming is certain.

Summary

The Paper Spatially explicit estimation of heat stress-related impacts of climate change on the milk production of dairy cows in the United Kingdom makes a number of assumptions to reach its headline conclusion of decreased milk yields due to heat stress by the end of the century. The assumption of constant prices defies the economic reality that prices fluctuate with changing supply. The assumption of dumb farmers defies the reality of a competitive market, where they have to respond to new information to stay in business. The assumption of 3.5°C warming in the UK can be taken as unlikely from either the belief Paris Climate Agreement with constrain further warming to 1°C or less OR that the inability of past climate projections to conform to the pattern of warming should give more than reasonable doubt that current projections are credible.  Further the authors seem to be unaware of the planning horizons of normal businesses. Where there will be no significant costs for decades, applying any sort of discount rate to potential investments will mean instant dismissal of any consideration of heat stress issues at the end of the century by the current generation of farmers.

Taking all these assumptions together makes one realize that it is quite dangerous for specialists in another field to take the long range projections of climate models and apply to their own areas, without also considering the economic and business realities.

Kevin Marshall 

UK Government Committee 7000 heat-deaths in 2050s assumes UK’s climate policies will be useless

Summary

Last week, on the day forecast to have record temperatures in the UK, the Environmental Audit Committee warns of 7,000 heat-related deaths every year in the UK by the 2050s if the Government did not act quickly. That prediction was based upon Hajat S, et al 2014. Two principle assumptions behind that prognosis did not hold at the date when the paper was submitted. First is that any trend of increasing summer heatwaves in the data period of 1993 to 2006 had by 2012 ended. The six following summers were distinctly mild, dull and wet. Second, based upon estimates from the extreme 2003 heatwave, is that most of the projected heat deaths would occur in NHS hospitals, is the assumption that health professionals in the hospitals would not only ignore the increasing death toll, but fail to take adaptive measures to an observed trend of evermore frequent summer heatwaves. Instead, it would require a central committee to co-ordinate the data gathering and provide the analysis. Without the politicians and bureaucrats producing reports and making recommendations the world will collapse.
There is a third, implied assumption, in the projection. The 7,000 heat-related deaths in the 2050s assumes the complete failure of the Paris Agreement to control greenhouse emissions, let alone keep warming to within any arbitrary 1.5°C or 2°C. That means other countries have failed to follow Britain’s lead in reducing their emissions by 80% by 2050. The implied assumption is that the considerable costs and hardships on imposed on the British people by the Climate Change Act 2008 will have been for nothing.

Announcement on the BBC

In the early morning of last Thursday – a day when there were forecasts of possible record temperatures – the BBC published a piece by Roger Harrabin “Regular heatwaves ‘will kill thousands’”, which began

The current heatwave could become the new normal for UK summers by 2040 because of climate change, MPs say.
The Environmental Audit Committee warns of 7,000 heat-related deaths every year in the UK by 2050 if the government doesn’t act quickly. 
Higher temperatures put some people at increased risk of dying from cardiac, kidney and respiratory diseases.
The MPs say ministers must act to protect people – especially with an ageing population in the UK.

I have left the link in. It is not to a Report by the EAC but to a 2014 paper mentioned once in the report. The paper is Hajat S, et al. J Epidemiol Community Health DOI: 10.1136/jech-2013-202449 “Climate change effects on human health: projections of temperature-related mortality for the UK during the 2020s, 2050s and 2080s”.

Hajat et al 2014

Unusually for a scientific paper, Hajat et al 2014 contains very clear highlighted conclusions.

What is already known on this subject

▸ Many countries worldwide experience appreciable burdens of heat-related and cold-related deaths associated with current weather patterns.

▸ Climate change will quite likely alter such risks, but details as to how remain unclear.

What this study adds

Without adaptation, heat-related deaths would be expected to rise by around 257% by the 2050s from a current annual baseline of around 2000 deaths, and cold-related mortality would decline by 2% from a baseline of around 41 000 deaths.

▸ The increase in future temperature-related deaths is partly driven by expected population growth and ageing.

▸ The health protection of the elderly will be vital in determining future temperature-related health burdens.

There are two things of note. First the current situation is viewed as static. Second, four decades from now heat-related deaths will dramatically increase without adaptation.
With Harrabin’s article there is no link to the Environmental Audit Committee’s report page, direct to the full report, or to the announcement, or even to its homepage.

The key graphic in the EAC report relating to heat deaths reproduces figure 3 in the Hajat paper.

The message being put out is that, given certain assumptions, deaths from heatwaves will increase dramatically due to climate change, but cold deaths will only decline very slightly by the 2050s.
The message from the graphs is if the central projections are true (note the arrows for error bars) in the 2050s cold deaths will still be more than five times the heat deaths. If the desire is to minimize all temperature-related deaths, then even in the 2050s the greater emphasis still ought to be on cold deaths.
The companion figure 4 of the Hajat et al 2014 should also be viewed.

Figure 4 shows that both heat and cold deaths is almost entirely an issue with the elderly, particularly with the 85+ age group.
Hajat et al 2014 looks at regional data for England and Wales. There is something worthy of note in the text to Figure 1(A).

Region-specific and national-level relative risk (95% CI) of mortality due to hot weather. Daily mean temperature 93rd centiles: North East (16.6°C), North West (17.3°C), Yorks & Hum (17.5°C), East Midlands (17.8°C), West Midlands (17.7°C), East England (18.5°C), London (19.6°C), South East (18.3°C), South West (17.6°C), Wales (17.2°C).

The coldest region, the North East, has mean temperatures a full 3°C lower than London, the warmest region. Even with high climate sensitivities, the coldest region (North East) is unlikely to see temperature rises of 3°C in 50 years to make mean temperature as high as London today. Similarly, London will not be as hot as Milan. there would be an outcry if the London had more than three times the heat deaths of Newcastle, or if Milan had had more than three times the heat deaths of London. So how does Hajat et al 2014 reach these extreme conclusions?
There are as number of assumptions that are made, both explicit and implicit.

Assumption 1 : Population Increase

(T)otal UK population is projected to increase from 60 million in mid-2000s to 89 million by mid-2080s

By the 2050s there is roughly a 30% increase in population. Heat death rates per capita only show a 150% increase in five decades.

 

Assumption 2 : Lack of improvement in elderly vulnerability
Taking the Hajat et al figure 4, the relative proportions hot and cold deaths between age bands is not assumed to change, as my little table below shows.

The same percentage changes for all three age bands I find surprising. As the population ages, I would expect the 65-74 and 74-84 age bands to become relatively healthier, continuing the trends of the last few decades. That will make them less vulnerable to temperature extremes.

Assumption 3 : Climate Sensitivities

A subset of nine regional climate model variants corresponding to climate sensitivity in the range of 2.6–4.9°C was used.

The compares to the IPCC AR5 WG1 SPM Page 16

Equilibrium climate sensitivity is likely in the range 1.5°C to 4.5°C (high confidence)

With a mid-point of 3.75°C compared to the IPCC’s 3°C does not make much difference over 50 years. The IPCC’s RCP8.5 unmitigated emissions growth scenario has 3.7°C (4.5-0.8) of warming from 2010 to 2100. Pro-rata the higher sensitivities give about 2.5°C of warming by the 2050s, still making mean temperatures in the North East just below that of London today.
The IPCC WG1 report was published a few months after the Hajat paper was accepted for publication. However, the ECS range 1.5−4.5 was unchanged from the 1979 Charney report, so there should be a least a footnote justifying the higher senitivitity. An alternative approach to these vague estimates derived from climate models is those derived from changes over the historical instrumental data record using energy budget models. The latest – Lewis and Curry 2018 – gives an estimate of 1.5°C. This finding from the latest research would more than halved any predicted warming to the 2050s of the Hajat paper’s central ECS estimate.

Assumption 4 : Short period of temperature data

The paper examined both regional temperature data and deaths for the period 1993–2006. This 14 period had significant heatwaves in 1995, 2003 and 2006. Climatically this is a very short period, ending a full six years before the paper was submitted.
From the Met Office Hadley Centre Central England Temperature Data I have produced the following graphic of seasonal data for 1975-2012, with 1993-2006 shaded.

Typical mean summer temperatures (JJA) were generally warmer than in both the period before and the six years after. Winter (DJF) average temperatures for 2009 to 2011 were the coldest three run of winters in the whole period. Is this significant?
A couple of weeks ago the GWPF drew attention to a 2012 Guardian article The shape of British summers to come?

It’s been a dull, damp few months and some scientists think we need to get used to it. Melting ice in Greenland could be bringing permanent changes to our climate
The news could be disconcerting for fans of the British summer. Because when it comes to global warming, we can forget the jolly predictions of Jeremy Clarkson and his ilk of a Mediterranean climate in which we lounge among the olive groves of Yorkshire sipping a fine Scottish champagne. The truth is likely to be much duller, and much nastier – and we have already had a taste of it. “We will see lots more floods, droughts, such as we’ve had this year in the UK,” says Peter Stott, leader of the climate change monitoring and attribution team at the Met Office. “Climate change is not a nice slow progression where the global climate warms by a few degrees. It means a much greater variability, far more extremes of weather.”

Six years of data after the end of the data period, but five months before the paper was submitted on 31/01/2013 and nine months before the revised draft was submitted, there was a completely new projection saying the opposite of more extreme heatwaves.
The inclusion more recent available temperature data is likely to have materially impacted on the modelled extreme hot and cold death temperature projections for many decades in the future.

Assumption 5 : Lack of Adaptation
The heat and cold death projections are “without adaptation”. This assumption means that over the decades people do not learn from experience, buy air conditioners, drink water and look out for the increasing vulnerable. People basically ignore the rise in temperatures, so by the 2050s treat a heatwave of 35°C exactly the same as one of 30°C today. To put this into context, it is worth looking as another papers used in the EAC Report.
Mortality in southern England during the 2003 heat wave by place of death – Kovats et al – Health Statistics Quarterly Spring 2006
The only table is reproduced below.

Over half the total deaths were in General Hospitals. What does this “lack of adaptation” assumption imply about the care given by health professionals to vulnerable people in their care? Surely, seeing rising death tolls they would be taking action? Or do they need a political committee in Westminster looking at data well after the event to point out what is happening under there very noses? Even when data been collated and analysed in such publications as the Government-run Health Statistics Quarterly? The assumption of no adaptation should have been alongside and assumption “adaptation after the event and full report” with new extremes of temperature coming as a complete surprise. However, that might still be unrealistic considering “cold deaths” are a current problem.

Assumption 6 : Complete failure of Policy
The assumption high climate sensitivities resulting in large actual rises in global average temperatures in the 2050s and 2080s implies another assumption with political implications. The projection of 7,000 heat-related deaths assumes the complete failure of the Paris Agreement to control greenhouse emissions, let alone keep warming to within any arbitrary 1.5°C or 2°C. The Hajat paper may not state this assumption, but by assuming increasing temperatures from rising greenhouse levels, it is implied that no effective global climate mitigation policies have been implmented. This is a fair assumption. The UNEP emissions Gap Report 2017 (pdf), published in October last year is the latest attempt to estimate the scale of the policy issue. The key is the diagram reproduced below.

The aggregate impact of climate mitigation policy proposals (as interpreted by the promoters of such policies) is much closer to the non-policy baseline than the 1.5°C or 2°C emissions pathways. That means other countries have failed to follow Britain’s lead in reducing their emissions by 80% by 2050. In its headline “Heat-related deaths set to treble by 2050 unless Govt acts” the Environmental Audit Committee are implicitly accepting that the Paris Agreement will be a complete flop. That the considerable costs and hardships on imposed on the British people by the Climate Change Act 2008 will have been for nothing.

Concluding comments

Projections about the consequences of rising temperatures require making restrictive assumptions to achieve a result. In academic papers, some of these assumptions are explicitly-stated, others not. The assumptions are required to limit the “what-if” scenarios that are played out. The expected utility of modeled projections is related to whether the restrictive assumptions bear relation to actual reality and empirically-verified theory. The projection of over 7,000 heat deaths in the 2050s is based upon

(1) Population growth of 30% by the 2050s

(2) An aging population not getting healthier at any particular age

(3) Climate sensitivities higher than the consensus, and much higher than the latest data-based research findings

(4) A short period of temperature data with trends not found in the next few years of available data

(5) Complete lack of adaptation over decades – an implied insult to health professionals and carers

(6) Failure of climate mitigation policies to control the growth in temperatures.

Assumptions (2) to (5) are unrealistic, and making any more realistic would significantly reduce the projected number of heat deaths in the 2050s. The assumption of lack of adaptation is an implied insult to many health professionals who monitor and adapt to changing conditions. In assuming a lack of climate mitigation policies implies that the £319bn Britain is projected is spent on combating climate change between 2014 and 2030 is a waste of money. Based on available data, this assumption is realistic.

Kevin Marshall

Plan B Environmental Activists deservedly lose High Court battle over Carbon Target

Breaking News

From Belfast Telegraph & itv.com and Science Matters (my bold)

Lawyers for the charity previously argued the Government should have, in light of the current scientific consensus, gone further than its original target of reducing carbon levels by 2050 to 80% of those present in 1990.

They said the decision not to amend the 2050 target put the UK in breach of its international obligations under the Paris Agreement on Climate Change and was influenced by the Government’s belief that a “more ambitious target was not feasible”.

At a hearing on July 4, Jonathan Crow QC told the court: “The Secretary of State’s belief that he needs to have regard to what is feasible, rather than what is necessary, betrays a fundamental misunderstanding of the scheme of the 2008 Act and must be quashed.

“All of the individual claimants are deeply concerned about climate change.”

The barrister argued the Secretary of State’s “continuing refusal” to amend the 2050 target means the UK is playing “Russian roulette with two bullets, instead of one”.

But, refusing permission for a full hearing, Mr Justice Supperstone said Plan B Earth’s arguments were based on an “incorrect interpretation” of the Paris Agreement.

He said: “In my view the Secretary of State was plainly entitled … to refuse to change the 2050 target at the present time.

In a previous post I wrote that

Taking court action to compel Governments to enforce the Paris Climate Agreement is against the real spirit of that Agreement. Controlling global GHG emissions consistent with 2°C, or 1.5°C is only an aspiration, made unachievable by allowing developing countries to decide for themselves when to start reducing their emissions. ……. Governments wanting to both be players on the world stage and serve their countries give the appearance of taking action of controlling emissions, whilst in substance doing very little. This is the real spirit of the Paris Climate Agreement. To take court action to compel a change of policy action in the name of that Agreement should be struck off on that basis.

Now I would not claim Mr Justice Supperstone supports my particular interpretation of the Paris Agreement as an exercise in political maneuvering allowing Governments to appear to be one thing, whilst doing another. But we are both agreed that “Plan B Earth’s arguments were based on an “incorrect interpretation” of the Paris Agreement.

The UNFCCC PDF of the Paris Agreement is here to check. Then check against my previous post, which argues that if the Government acted in the true spirit of the Paris Agreement, it would suspend the costly Climate Change Act 2008 and put efforts into being seen to be doing something about climate change. Why

  • China was praised for joining the emissions party by proposing to stop increasing emissions by 2030.
  • Very few of the INDC emissions will make real large cuts in emissions.
  • The aggregate forecast impact of all the INDC submissions, if fully enacted, will see global  emissions slightly higher than today in 2030, when according to the UNEP emissions GAP report 2017 for 1.5°C warming target they need to be 30% lower in just 12 years time. Paris Agreement Article 4.1 states something that is empirically incompatible with that aim.

In order to achieve the long-term temperature goal set out in Article 2, Parties aim to reach global peaking of greenhouse gas emissions as soon as possible, recognizing that peaking will take longer for developing country Parties,

  • The Paris Agreement allows “developing” countries to keep on increasing their emissions. With about two-thirds of global emissions (and over 80% of the global population), 30% emissions cuts may not be achieved even if all the developed countries cut emissions to zero in 12 years.
  • Nowhere does the Paris Agreement recognize the many countries who rely on fossil fuels for a large part of their national income, for instance in the Middle East and Russia. Cutting emissions to near zero by mid-century would impoverish them within a generation. Yet, with the developing countries also relying on cheap fossil fuels to promote high levels of economic growth for political stability and to meeting the expectations of their people (e.g. Pakistan, Indonesia, India, Turkey) most of the world can carry on for decades whilst some enlightened Governments in the West damage the economic futures of their countries for appearances sake. Activists trying to dictate Government policy through the Courts in a supposedly democratic country ain’t going to change their minds.

Plan B have responded to the judgement. I find this statement interesting.

Tim Crosland, Director of Plan B and former government lawyer, said: ‘We are surprised and disappointed by this ruling and will be lodging an appeal.

‘We consider it clear and widely accepted that the current carbon target is not compatible with the Paris Agreement. Neither the government nor the Committee on Climate Change suggested during our correspondence with them prior to the claim that the target was compatible.

Indeed, it was only in January of this year that the Committee published a report accepting that the Paris Agreement was ‘likely to require’ a more ambitious 2050 target

What I find interesting is that only point that a lawyer has for contradicting Mr Justice Supperstone’s statement that “Plan B Earth’s arguments were based on an “incorrect interpretation” of the Paris Agreement” is with reference to a report by the Committee on Climate Change. From the CCC website

The Committee on Climate Change (the CCC) is an independent, statutory body established under the Climate Change Act 2008.

Our purpose is to advise the UK Government and Devolved Administrations on emissions targets and report to Parliament on progress made in reducing greenhouse gas emissions and preparing for climate change.

The Committee is set up for partisan aims and, from its’s latest report, appears to be quite zealous in fulfilling those aims. Even as a secondary source (to a document which is easy to read) it should be tainted. But, I would suggest that to really understand the aims of the Paris Agreement you need to read the original and put it in the context of the global empirical and political realities. From my experience, the climate enlightened will keep on arguing for ever, and get pretty affronted when anyone tries to confront their blinkered perspectives.

Kevin Marshall

Why Plan B’s Climate Court Action should be dismissed

Summary

Taking court action to compel Governments to enforce the Paris Climate Agreement is against the real spirit of that Agreement. Controlling global GHG emissions consistent with 2°C, or 1.5°C is only an aspiration, made unachievable by allowing developing countries to decide for themselves when to start reducing their emissions. In the foreseeable future, the aggregate impact of emissions reduction policies will fail to even reduce global emissions. Therefore, costly emissions reductions policies will always end up being net harmful to the countries where they are imposed. Governments wanting to both be players on the world stage and serve their countries give the appearance of taking action of controlling emissions, whilst in substance doing very little. This is the real spirit of the Paris Climate Agreement. To take court action to compel a change of policy action in the name of that Agreement should be struck off on that basis. I use activist group Plan B’s case before the British Court to get the British Government to make even deeper emissions cuts than those under the Climate Change Act 2008.

Plan B’s Case at the High court

Last week BBC’s environment analyst Roger Harrabin reported Court action to save young from climate bill.

The campaigners – known collectively as Plan B – argue that if the UK postpones emissions cuts, the next generation will be left to pick up the bill.

It is seeking permission from a judge to launch formal legal action.

The government has promised to review its climate commitments.

A spokesperson said it was committed to tackling emissions.

But Plan B believes ministers may breach the law if they don’t cut emissions deeper – in line with an international agreement made in Paris at the end of 2015 to restrict global temperature rise to as close to 1.5C as possible.

From an obscure website crowdjustice

Plan B claim that the government is discriminating against the young by failing to cut emissions fast enough. During the hearing, they argued that the UK government’s current target of limiting global temperature rises to 2°C was not ambitious enough, and that the target ought to be lowered to 1.5°C, in line with the Paris Agreement that the UK ratified in 2015. Justice Supperstone postponed the decision until a later date.

Plan B on their own website state

Plan B is supporting the growing global movement of climate litigation, holding governments and corporations to account for climate harms, fighting for the future for all people, all animals and all life on earth.

What is the basis of discrimination?

The widely-accepted hypothesis is that unless global greenhouse gas (GHG) emissions are reduced to near zero in little more than a generation, global average temperature rise will rise more than 2°C above pre-industrial levels. A further hypothesis is that this in turn will cause catastrophic climate change. Consequent on both hypotheses being true gives the case for policy action. Therefore, failure to reduce global GHG emissions will imperil the young.

A further conjecture is that if all signatories to the Paris Agreement fulfil their commitments it is sufficient to prevent 1.5°C or 2°C of warming. There are a number of documents to consider.

First is the INDC submissions (i.e. Nation States communications of their intended nationally determined contributions), collected together at the UNFCCC website. Most are in English.  To find a country submission I suggest clicking on the relevant letter of the alphabet.

Second, to prevent my readers being send on a wild goose chase through small country submissions, some perspective is needed on relative magnitude of emissions. A clear secondary source (but only based on CO2 emissions) BP Data Analysis Global CO2 Emissions 1965-2017. More data on GHG emissions are from the EU Commissions EDGAR Emissions data and the World Resources Institute CAIT Climate Data Explorer.

Third is the empirical scale of the policy issue. The UNEP emissions Gap Report 2017 (pdf), published in October last year is the latest attempt to estimate the scale of the policy issue. The key is the diagram reproduced below.

The total of all commitments will still see aggregate emissions rising into the future. That is, the aggregate impact of all the nationally determined contributions is to see emissions rising well into the future. So the response it to somehow persuade Nations States to change their vague commitments to such an extent that aggregate emissions pathways sufficient to prevent 1.5°C or 2°C of warming?

The relevant way to do this ought to be through the Paris Agreement.

Fourth is the Adoption Paris Agreement itself, as held on the UNFCCC website (pdf).

 

Paris Agreement key points

I would draw readers to Article 2.1(a)

  • Holding the increase in the global average temperature to well below 2°C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5°C above pre-industrial levels, recognizing that this would significantly reduce the risks and impacts of climate change;

Article 2.2

  • This Agreement will be implemented to reflect equity and the principle of common but differentiated responsibilities and respective capabilities, in the light of different national circumstances.

My interpretation is that the cumulative aggregate reduction will be only achieved by if those countries that (in the light of their national circumstances) fail to follow the aggregate pathways, are offset by other countries cutting their emissions by a greater amount. It is a numbers game. It is not just a case of compelling some countries to meet the 1.5°C pathway but to compel them to exceed it by some margin.

I would also draw readers to Article 4.1

In order to achieve the long-term temperature goal set out in Article 2, Parties aim to reach global peaking of greenhouse gas emissions as soon as possible, recognizing that peaking will take longer for developing country Parties, and to undertake rapid reductions thereafter in accordance with best available science, so as to achieve a balance between anthropogenic emissions by sources and removals by sinks of greenhouse gases in the second half of this century, on the basis of equity, and in the context of sustainable development and efforts to eradicate poverty.

My reading is that any country defined as “developing” has only an aim of reducing emissions after peaking of their emissions. When they choose to do so depends on a number of criteria. There is not clear mechanism for deciding this, and no surrender of decision-making by countries to external bodies.

Implications of the Paris Agreement

Many developing countries emissions are increasing their emissions. They agreement does not compel them to change course in the near future. Empirically that means to achieve the goals the aggregate emission reductions of countries reducing their emissions must be such that they cancel out the emissions increases in the developing countries. Using EDGAR figures for GHG emissions, and the Rio Declaration 1992 for developing countries (called Non-Annex countries) I estimate they accounted for 64% of global GHG emissions in 2012, the latest year available.

 

All other sources sum to 19 GtCO2e, the same as the emissions gap between the unconditional INDC case and the 1.5°C case. This presents a stark picture. Even if emissions from all other sources are eliminated by 2030, AND the developing countries do not increase their emissions to 2030, cumulative global emissions are very likely to exceed the 1.5°C and the 2°C warming targets unless the developing countries reduce their emissions rapidly after 2030. That is close down fairly new fossil fuel power stations; remove from the road millions of cars, lorries and buses; and reduce the aspirations of the emerging middle classes to improving life styles. The reality is quite the opposite. No new policies are on the horizon that would significantly reduce global GHG emissions, either from the developed countries in the next couple of years, or the developing countries to start in just over a decade from now. Reading the comments in the INDC emissions (e.g. Indonesia, Pakistan, India), a major reason is that these governments are not willing to sacrifice the futures of their young through risking economic growth and political stability to cut their emissions. So rather than Plan B take the UK Government  to a UK Court, they should be persuading those Governments who do not share their views (most of them) of the greater importance of their case. After all, unlike proper pollution (such as smoke), it does not matter where the emissions are generated in relation to the people affected.

It gets worse. It could be argued that the countries that most affected by mitigation policies are not the poorest seeing economic growth and political stability smashed. It is the fossil fuel dependent countries. McGlade and Ekins 2015 (The geographical distribution of fossil fuels unused when limiting global warming to 2°C) estimated, said to achieve even 2°C target 75% of proven reserves and 100% of new discoveries must be left in the ground. Using these global estimates and the BP estimated proven reserves of fossil fuels I created the following apportionment by major countries.

 

The United States has the greatest proven fossil fuel reserves in terms of potential emissions. But if one looks at fossil fuel revenues relative to GDP, it is well down the league table. To achieve emission targets countries such like Russia, Saudi Arabia, Kuwait, Turkmenistan, Iraq, and Iran must all be persuaded to shut down their down sales of fossil fuels long before the reserves are exhausted, or markets from developing countries dry up. To do this in a generation would decimate their economies. However, given the increase in fossil fuel usage from developing countries, and the failure of developed countries to significantly reduce emissions through policy this hardly seems a large risk.

However, this misses the point. The spirit of the Paris Agreement is not to cut emissions, but to be seen to be doing something about climate change. For instance, China were held up by the likes of President Obama for aiming to both top out its emissions by 2030, and reduce emissions per unit of GDP. The USA and the EU did this decades ago, so China’s commitments are little more than a Business-as-usual scenario. Many other countries emissions reduction “targets” are attainable without much actual policy. For example, Brazil’s commitment is to “reduce greenhouse gas emissions by 43% below 2005 levels in 2030.” It sounds impressive, until one reads this comment under “Fairness and Ambition

Brazil’s current actions in the global effort against climate change represent one of the largest undertakings by any single country to date, having reduced its emissions by 41% (GWP-100; IPCC SAR) in 2012 in relation to 2005 levels.

Brazil intends to reduce emissions by a further 2% compared to 2005 levels. Very few targets are more than soft targets relative to current or projected trends. Yet the outcome of COP21 Paris enabled headlines throughout the world to proclaim a deal had been reached “to limit global warming to “well below” 2C, aiming for 1.5C”. It enables most Governments to juggle being key players on a world stage, have alarmists congratulating them on doing their bit on saving the planet, whilst making sure that serving the real needs of their countries is not greatly impeded. It is mostly win-win as long as countries do not really believe that targets are achievable. This is where Britain has failed. Under Tony Blair, when the fever of climate alarmism at its height, backed up by the political spin of New Labour and a Conservative opposition wanting to ditch its unelectable image, Green activists wrote the Climate Change Act 2008 with the strict targets to be passed. Britain swallowed climate alarmism whole, and now as a country that keep its promises is implementing useless and costly policies. But they have kept some form of moderation in policies until now. This is illustrated by a graphic from a Committee on Climate Change report last week “Reducing UK emissions 2018 – Progress Report to Parliament” (pdf) (and referenced at cliscep)

Whilst emissions have come down in the power sector they are flat in transport, industry and in buildings. Pushing real and deep reductions in these sectors means for young people pushing up the costs of motoring (placing driving a car out of the reach of many), of industry (raising costs relative to the countries – especially the non-policy developing countries) and buildings in a country where planning laws make home-owning unaffordable for many and where costs of renting is very high. This on top of further savings in the power industry will be ever more costly as the law of diminishing returns sets in. Forcing more urgent policy actions will increase the financial and other burdens on the young people of today, but do virtually nothing to reach the climate aspirations of the Paris Agreement due to Britain now having less than 1% of global emissions. The Government could be forced out of political fudging to impose policies that will be net harmful to the young and future generations.

Plan B are using an extreme activist interpretation. As reported in Climate Home News after the postponement.

“The UK is not doing enough,” Tim Crosland, director of Plan B told Climate Home News. “The benchmark target is now out of place. We are arguing that it is a breach of human rights.”

The UK has committed to cut emissions by at least 80% of 1990 levels by 2050, with an aim to limit global temperature rise to 2C.

Under the 2008 Climate Change Act, the secretary can revise the target to reflect significant developments in climate change science or in international law or policy.

Plan B want to see the target lowered to be in line with 1.5C, the lower target of the Paris Agreement, which the UK ratified in 2016.

As stated, insofar as the Paris Climate Agreement is a major development of policy, it is one of appearing to do a lot whilst doing very little. By these terms, the stronger case is for repealing the Act, not strengthening its clauses. 

But what if I am wrong on this Paris Agreement being just an exercise in appearances? This then it should be recognized that developing countries will only start to reduce their emissions at some time in the future. By implication, for the world to meet the 1.5°C warming limit, developing countries should be pursuing and emissions reduction pathway much steeper than the 25% reduction between 2015 and 2030 implied in the Emissions GAP Report graphic. It should be at least 50% and nearer 100% in the next decade. Given that the Climate Change Act was brought in so that Britain could lead the world on climate change, Plan B should be looking for a 100% reduction by the end of the year. 

Kevin Marshall

 

Hansen et al 1988 Global Warming Predictions 30 Years on

Last month marked the 30th anniversary of the James Hansen’s Congressional Testimony that kicked off the attempts to control greenhouse gas emissions. The testimony was clearly an attempt, by linking human greenhouse emissions to dangerous global warming, to influence public policy. Unlike previous attempts (such as by then Senator Al Gore), Hansen’s testimony was hugely successful. But do the scientific projections that underpinned the testimony hold up against the actual data? The key part of that testimony was a graph from the Hansen et al 1988* Global climate changes as forecast by Goddard Institute for Space Studies three-dimensional model, produced below.


Figure 1: Hansen et al 1988 – Figure 3(a) in the Congressional Testimony

Note the language of the title of the paper. This is a forecast of global average temperatures contingent upon certain assumptions. The ambiguous part is the assumptions.

The assumptions of Hansen et. al 1988

From the paper.

4. RADIATIVE FORCING IN SCENARIOS A, B AND C

4.1. Trace Gases

  We define three trace gas scenarios to provide an indication of how the predicted climate trend depends upon trace gas growth rates. Scenarios A assumes that growth rates of trace gas emissions typical of the 1970s and 1980s will continue indefinitely; the assumed annual growth averages about 1.5% of current emissions, so the net greenhouse forcing increase exponentially. Scenario B has decreasing trace gas growth rates, such that the annual increase of the greenhouse climate forcing remains approximately constant at the present level. Scenario C drastically reduces trace gas growth between 1990 and 2000 such that the greenhouse climate forcing ceases to increase after 2000.

Scenario A is easy to replicate. Each year increase emissions by 1.5% on the previous year. Scenario B assumes that growth emissions are growing, and policy takes time to be enacted. To bring emissions down to the current level (in 1987 or 1988), reduction is required. Scenario C one presumes are such that trace gas levels are not increasing. As trace gas levels were increasing in 1988 and (from Scenario B) continuing emissions at the 1988 level would continue to increase atmospheric levels the levels of emissions would have been considerably lower than in 1988 by the year 2000. They might be above zero, as small amounts of emissions may not have an appreciable impact on atmospheric levels.

The graph formed Fig. 3. of James Hansen’s testimony to Congress. The caption to the graph repeats the assumptions.

Scenario A assumes continued growth rates of trace gas emissions typical of the past 20 years, i.e., about 1.5% yr-1 emission growth; scenario B has emission rates approximately fixed at current rates; scenario C drastically reduces traces gas emissions between 1990 and 2000.

This repeats the assumptions. Scenario B fixes annual emissions at the levels of the late 1980s, whilst scenario C sees drastic emission reductions.

James Hansen in his speech gave a more succinct description.

We have considered cases ranging from business as usual, which is scenario A, to draconian emission cuts, scenario C, which would totally eliminate net trace gas growth by year 2000.

Note that the resultant warming from fixing emissions at the current rate (Scenario B) is much closer in warming impacts to Scenario A (emissions growth of +1.5% year-on-year) than Scenario C that stops global warming. Yet Scenario B results from global policy being successfully implemented to stop the rise in global emissions.

Which Scenario most closely fits the Actual Data?

To understand which scenario most closely fits the data, we need to look at that trace gas emissions data. There are a number of sources, which give slightly different results. One source, and that which ought to be the most authoritative, is the IPCC Fifth Assessment Report WG3 Summary for Policy Makers graphic SPM.1 is reproduced in Figure 2.

 Figure 2 : AR5 WG3 SPM.1 Total annual anthropogenic GHG emissions (GtCO2eq/yr) by groups of gases 1970-2010. FOLU is Forestry and Other Land Use.

Note that in Figure 2 the other greenhouse gases – F-Gases, N2O and CH4 – are expressed in CO2 equivalents. It is very easy to see which of the three scenarios fits. The historical data up until 1988 shows increasing emissions. After that data emissions have continued to increase. Indeed there is some acceleration, stated on the graph comparing 2000-2010 (+2.2%/yr) with 1970-2000 (+1.3%/yr) . In 2010 GHG emissions were not similar to those in the 1980s (about 35 GtCO2e) but much higher. By implication, Scenario C, which assumed draconian emissions cuts is the furthest away from the reality of what has happened. Before considering how closely Scenario A compares to temperature rise, the question is therefore how close actual emissions have increased compared to the +1.5%/yr in scenario A.

From my own rough calculations, total GHG emissions from 1990 to 2010 rose about 29% or 1.3% a year, compared to 41% or 1.7% a year in the period 1970 to 1990. Exponential growth of 1.3% is not far short of the 1.5%. The assumed 1.5% growth rates would have resulted in 2010 emissions of 51 GtCO2e instead of the 49 GtCO2e estimated, well within the margin of error. That is actual trends over 20 years were pretty much the business as usual scenario. The narrower CO2 emissions from fossil fuels and industrial sources from 1990 to 2010 rose about 42% or 1.8% a year, compared to 51% or 2.0% a year in the period 1970 to 1990, above the Scenario A.

The breakdown is shown in Figure 3.

Figure 3 : Rough calculations of exponential emissions growth rates from AR5 WG1 SPM Figure SPM.1 

These figures are somewhat out of date. The UNEP Emissions Gap Report 2017 (pdf) estimated GHG emissions in 2016 at 51.9 GtCO2e. This represents a slowdown in emissions growth in recent years.

Figure 4 shows are the actual decadal exponential growth trends in estimated GHG emissions (with a linear trend to the 51.9 GtCO2e of emissions in 2016 from the UNEP Emissions Gap Report 2017 (pdf)) to my interpretations of the scenario assumptions. That is, from 1990 in Scenario A for 1.5% annual growth in emissions; in Scenario B for emissions to reduce from 38 to 35 GtCO2e in(level of 1987) in the 1990s and continue indefinitely: in Scenario C to reduce to 8 GtCO2e in the 1990s.

Figure 4 : Hansen et al 1988 emissions scenarios, starting in 1990, compared to actual trends from UNIPCC and UNEP data. Scenario A – 1.5% pa emissions growth; Scenario B – Linear decline in emissions from 38 GtCO2e in 1990 to 35 GtCO2e in 2000, constant thereafter; Scenario C – Linear decline  in emissions from 38 GtCO2e in 1990 to 8 GtCO2e in 2000, constant thereafter. 

This overstates the differences between A and B, as it is the cumulative emissions that matter. From my calculations, although in Scenario B 2010 emissions are 68% of Scenario A, cumulative emissions for period 1991-2010 are 80% of Scenario A.

Looking at cumulative emissions is consistent with the claims from the various UN bodies, that limiting to global temperature rise to 1.5°C or 2.0°C of warming relative to some point is contingent of a certain volume of emissions not been exceeded. One of the most recent the key graphic from the UNEP Emissions Gap Report 2017.

Figure 5 : Figure ES.2 from the UNEP Emissions Gap Report 2017, showing the projected emissions gap in 2030 relative to 1.5°C or 2.0°C warming targets. 

Warming forecasts against “Actual” temperature variation

Hansen’s testimony was a clear case of political advocacy. By making Scenario B constant the authors are making a bold policy statement. That is, to stop catastrophic global warming (and thus prevent potentially catastrophic changes to climate systems) requires draconian reductions in emissions. Simply maintaining emissions at the levels of the mid-1980s will make little difference. That is due to the forcing being related to the cumulative quantity of emissions.

Given that the data is not in quite in line with scenario A, if the theory is correct, then I would expect:-

  1. Warming trend to be somewhere between Scenario A and Scenario B. Most people accept 4.2equilibrium climate sensitivity of the Hansen model was 4.2ºC for a doubling of CO2 was too high. The IPCC now uses 3ºC for ECS. More recent research has it much lower still. However, although the rate of the warming might be less, the pattern of warming over time should be similar.
  2. Average temperatures after 2010 to be significantly higher than in 1987.
  3. The rate of warming in the 1990s to be marginally lower than in the period 1970-1990, but still strongly positive.
  4. The rate of warming in the 2000s to be strongly positive marginally higher than in the 1990s.

From the model Scenario C, there seems to be about a five year lag in the model between changes in emission rates and changes in temperatures. However, looking at the actual temperature data there is quite a different warming pattern. Five years ago C3 Headlines had a post 2013: The NASA/Hansen Climate Model Prediction of Global Warming Vs. Climate Reality.  The main graphic is in Figure 6

Figure 6 : C3 Headlines – NASA Hansen Prediction Vs Reality

The first thing to note is that the Scenario Assumptions are incorrect. Not only are they labelled as CO2, not GHG emissions, but are all stated wrongly. Stating them correctly would show a greater contradiction between forecasts and reality. However, the Scenario data appears to be reproduced correctly, and the actual graph appears to be in line with a graphic produced last month by Gavin Schmidt last month in his defense of Hansen’s predictions.

The data contradicts the forecasts. Although average temperatures are clearly higher than in in 1987, they are not in line with the forecast of Scenario A which is closest to the actual emissions trends. The rise is way below 70% of the model implied by inputting the lower IPCC climate sensitivity, and allowing for GHG emissions being fractional below the 1.5% per annum of Scenario A. But the biggest problem is where the main divergence occurred. Rather than warming accelerating slightly in the 2000s (after a possible slowdown in the 1990s),  there was no slowdown in the 1990s, but it either collapsed to zero, or massively reduced, depending on the data set was used. This is in clear contradiction of the model. Unless there is an unambiguous and verifiable explanation (rather than a bunch of waffly and contradictory excuses ), the model should be deemed to be wrong. There could be natural and largely unknown natural factors or random data noise that could explain the discrepancy. But equally (and quite plausibly) those same factors could have contributed to the late twentieth century warming.

This simple comparison has an important implication for policy. As there is no clear evidence to link most of the observed warming to GHG emissions, by implication there is no clear support for the belief that reducing GHG emissions will constrain future warming. But reducing global GHG emissions is merely an aspiration. As the graphic in Figure 5 clearly demonstrates, over twenty months after the Paris Climate Agreement was signed there is still no prospect of aggregate GHG emissions falling through policy. Hansen et. al 1988 is therefore a double failure; both as a scientific forecast and a tool for policy advocacy in terms of reducing GHG emissions. If only the supporters would realize their failure, and the useless and costly climate policies could be dismantled.

Kevin Marshall

*Hansen, J., I. Fung, A. Lacis, D. Rind, S. Lebedeff, R. Ruedy, G. Russell, and P. Stone, 1988: Global climate changes as forecast by Goddard Institute for Space Studies three-dimensional model. J. Geophys. Res., 93, 9341-9364, doi:10.1029/JD093iD08p09341.