Has Kevin Trenberth Reversed his position on Reversing the Null Hypothesis?

There is an interesting quote from Kevin Trenberth at SciGuy on Hurricane Sandy

It is true that hurricanes normally recurve and head east, especially at this time of year. So we do have a negative NAO and some blocking anticyclone in place, but the null hypothesis has to be that this is just “weather” and natural variability.

(emphasis mine)

Now would this be the same Kevin Trenberth who just 12 months ago was advocating that we reverse the null hypothesis?

“Humans are changing our climate. There is no doubt whatsoever,” said Trenberth. “Questions remain as to the extent of our collective contribution, but it is clear that the effects are not small and have emerged from the noise of natural variability. So why does the science community continue to do attribution studies and assume that humans have no influence as a null hypothesis?”

Has Trenberth now reversed his position on reversing the null hypthosis?

(I linked to SciGuy from Wattsupwiththat)

Comment made at Jo Nova’s Weekend Unthreaded.

Stephan Lewandowsky on Hurricane Sandy

Jo Nova posts on Stephan Lewandowsky’s analysis of Hurricane Sandy. Below is my comment, with the relevant links.

Lewandowsky has a lot to say about the overwhelming evidence for smoking causing lung cancer, but in substance has just this to say about the impending catastrophic global warming.

Trends such as the tripling of the number of weather-related natural disasters during the last 30 years or the inexorable rise in sea levels. Climate scientists predicted those trends long ago. And they are virtually certain that those trends would not have occurred without us pumping billions of tons of CO2 into the atmosphere.

There are 3 parts to this.

First, the economic analysis of natural disasters is Lewandowsky’s own. He ignores completely the opinions of Roger Pielke Jr, an expert in the field, with many peer reviewed studies on the subject. Pielke Jnr has shown there is nothing exceptional in the normalised cost of Hurricane Sandy. Furthermore, a 2009 report showed that New York is vulnerable to hurricanes, and the shape of the coastline makes it particularly vulnerable to storm surges.

Second, the sea level rise is a trivial issue. From the University of Colorado graph, it is clear that sea levels are rising at a steady rate of 31cm a century.

Third, he claims the predictions of unnamed “experts” have been fulfilled. A balanced analysis would point out that the CO2 levels have risen faster than predicted, but temperatures have not.

Last week I posted a proposal for analysing the costly impacts of global warming. Using the “equation”, I would suggest Lewandowsky overstates both the Magnitude and Likelihood that Sandy was caused by global warming. He misperceives the change in frequency (1/t). Furthermore, given than he has a track record in the highly biased use of statistics in his own field, and his deliberate lack of balance, the Weighting attached to anything he says should be negative. That is, like to newspapers of the Soviet Union, if Lewandowsky claims something, we should read between the lines to see what he does not say. However, unlike the Soviet Union we are still able to look for alternative opinions.


Normalized US Hurricane damage impacts


2012_rel4: Global Mean Sea Level Time Series (seasonal signals removed)