Hottest Summer Evah? Not According To CET.

By Paul Homewood

The Met Office are desperate to show this summer as the hottest evah:

August was a fairly average month but it marked the end of what was a remarkable summer for many.

With one day to go, it is clear that 2018 has been one of the hottest summers on record for the UK, however, the margin between the mean temperatures at the top of the league tables (records dating back to 1910) is so small that at this point it is impossible to say if 2018 will be an outright winner. It is very close to the record-breaking summers of 2006 (15.78C), 2003 (15.77C), and 1976 (15.77C) all of which are within 0.01C of each other.

The margin is so small that different datasets and different regions of the UK will have different ranking. Usually we will only quote statistics to the nearest 0.1C as differences smaller than this could result from small numerical differences arising from the statistical calculations. A more comprehensive analysis of the 2018 summer data will be undertaken early next week and data for summer 2018 will continue to be analysed over the coming months.

However, it looks more likely that it could be the warmest summer on record for England with the mean temperature standing at 17.2 C with one day to go, which would narrowly beat the record set in 1976 (17.0C). It is not going to be a record for Scotland, Northern Ireland or Wales where the records stand at 14.1C (2003), 15.5C (1995) and 16.1C (1995), respectively.

To get an even longer-term perspective our multi-century Central England Temperature* (CET) series dates back to 1659. In this dataset summer 2018 looks likely to slip behind the summers of 1976 and 1826. If we look back through the CET series only 10 summers recorded an average temperature above 17C. Six of those have occurred since 1976, and only two (1826, 1846) were pre 20^th Century, which is consistent with the general picture of our warming climate globally and here in the UK.

https://www.metoffice.gov.uk/news/releases/2018/end-of-summer-stats

Large questions remain about the accuracy of the Met Office’s calculations. They gloss over the CET, which is undoubtedly the gold standard of UK temperature series. In fact, this summer only ranks fifth warmest behind 1976, 1826, 1995 and 2003 (in that order). There is no comparison with 1976, which finished at 17.77C, compared to 17.27C this year.

https://www.metoffice.gov.uk/hadobs/hadcet/ssn_HadCET_mean.txt

In terms of average daily maximums, 1976 was 0.74C hotter than 2018.

It is hard to see how the Met Office can conclude that this summer is close to 1976 in the UK as a whole.

CET, of course, only covers Central England, but as the map shows, that is precisely where the intense heat has been this summer. Scotland, N Ireland and Wales are all nowhere being a record. Along with northern England, this should have pulled down the UK figures, in comparison with CET.

Click to enlarge image

Whereas CET is very carefully homogenised and relies on three high quality stations, Rothamsted, Pershore and Stonyhurst, the UK numbers are derived from a large number of sites, some of which have dubious provenance.

Although the Met Office don’t actually publish the stations used (at least as far as I know), their network of synoptic and climate stations includes questionable sites such as Heathrow, Faversham, a whole host of urban locations, not to mention Motherwell, which as we know is in the middle of a car park.

What we can say though is that this summer the heat was nowhere near as intense as 1976, or other recent summers:

https://www.metoffice.gov.uk/hadobs/hadcet/cet_info_mean.html

In 1976, there were nine days in CET that were over 30C, with the highest still a record at 33.2C. This year only one day topped 30C, and that was only 30.7C.

The summers of 1975, 1995, 2003 and 2006 all featured much higher temperatures:

Laughingly, the Met Office refer to the fact that hot summers were not as common pre 20thC. Have they not heard of the Little Ice Age?

With wall to wall sunshine for the best part of three months, this summer should have beaten all records, if global warming had anything to do with it. The fact that it did not even get near to 1826 rather says it all!