Today, the Met Office published its State of the UK Climate 2024. The BBC wrote an unquestioning article. On sea-level rise it stated.
For the first time this report highlights that UK sea level is rising faster than the global average.
As sea levels continue to rise around the UK, the risk of flooding is only going to increase further, says Dr Svetlana Jevrejeva from the National Oceanography Centre.
The examples that the BBC gives of flooding in 2024 at Tetbury and Stratford-upon-Avon are significantly above sea level, and many miles inland. But why let facts get in the way of a good narrative.
On sea-level rise, the Met Office Executive Summary states
Sea level rise around the UK is accelerating.
- Since 1901, the sea level around the UK has risen by about 19.5 cm, with two-thirds of this rise happening in just over the last three decades.
- The last 3 years were the three highest on record for UK annual mean sea level in a series from 1901, with the 21st Century so far (2001–2024) including the 17 highest years.
- Over the past 32 years (1993–2024) UK sea level has risen by 13.4 cm. This is higher than the global estimate of 10.6 cm calculated from satellite altimetry over the same period,
My first reaction on reading this was to assume that the Met Office had copied the methodology of the IPCC AR6 2022. That is, to splice the tide-gauge average data of 1901-1992 with the satellite data from 1993, then hope no one would notice that this splicing accounted for nearly all the apparent acceleration. However, although the year 1993 is there, it is apparent that the comments are derived from a single UK data set. A little research gets a graph of “long-term British sea level mean of five locations” at the National Tidal and Sea Level Facility. I have annotated the graph a little.
The graph does show that 2024 sea levels were about 19.5cm higher than in 1901. But 2024 sea levels were more like 10.5 cm higher than in 1993, not 13.4 cm. Further from 1992 to 1993, sea levels fell dramatically. Almost 7cm, equivalent to a third of the net increase over 124 years. From 1992 to 2024 sea levels rose about 3.8 cm or 1.2 mm yr-1, compared with 1.6 mm yr-1 in 1901-2024. In future Met Office ought to get a professional statistician to calculate trends and perform significance and sensitivity tests on the data. As for the 2024 report, it should be reissued with the unsubstantiated claims about accelerating sea-level rise removed.
This is an expanded version of a comment made at Paul Homewood’s notalotofpeopleknowthat blog.
ManicBeancounter 