Urban Heat Islands in Central England

Central England Battle of the Heat Islands

People have asked me about urbanization influences in the CRU / Jones temperature trends for the United Kingdom.
It has been suggested that these temperature records would be so well known to CRU and The Met Office that the CRU / Jones UK suite would be clean of influences from Urban Heat Islands (UHI).
A quick look at Manchester, Birmingham and Gatwick airports and the small city of Waddington, for the period 1951 to 1995 shows no lack of artificial warming. Stations referred to are shown on map from MS Encarta 2000.

Differencing all four urban stations with the rural site "Valley" on the NW tip of Wales, it can be seen that Gatwick Airport has the most severe UHI contamination. Manchester might have a cooling step at 1988, while both Birmingham / Elmdon Airport and Waddington have closely comparable trends. If there was a rural station in the Jones 1994 data closer to the group of urban stations for the 1951-1995 period, then it would have been used instead of the coastal Valley, which is not perfect.
Note the several simultaneous steps in the difference trends near 1962, 1971, 1977, & 1988, which suggest a series of warming steps in Valley.

When the warming trend of about 0.3 degrees over the 45 years in Valley is taken into account, Manchester AP warms at 0.4 degrees in 45 years, Birmingham AP warms at 0.7 degrees in 45 years, Gatwick warms 0.9 degrees in 35 years and Waddington, 0.7 degrees in 45 years.

The case for the series of warming steps in Valley is supported by the differences between the Irish stations Valencia Observatory and Malin Head and Valley, see map above. The graph below shows that both these difference trends indicate non-climatic warming in Valley of about 0.3 degrees over the 45 years.

None of the stations reviewed above were subjected to any corrections by CRU / Jones 1994.

The data used is all from Jones 1994.

This review is another nail in the coffin of this ridiculous notion that moving a temperature recording site to an airport somehow eliminates UHI influence. (see my page on Sydney).

Just another numbing example of the gross underestimation of the extent of UHI contamination by this research group.

In this case of course there is The Met Office, arguably the premier weather / climate group in the world, with many more data
available than CRU / Jones have used.

I am not aware of any comments by Met Office people to the Journals pointing out for example the UHI at Gatwick and the
other stations mentioned above. It would be interesting to know what increase there has been in Met Office research funding over the last 15 years due to the IPCC inspired greenhouse / global warming issue.

Addition 24, August, 2000

Since posting this page on the 21st I have downloaded the Central England Temperature (CET) Series 1659 to 1999, (Parker et al 1992), from the Met Office web site, thank you all very much.
The only long term non urban station I can see to compare CET with is Valentia Observatory on the SW tip of Ireland, see map above. Valentia runs from 1869 and I used the GISS version because they have data into 2000.

The graph below of CET minus Valentia indicates that CET is warming at about the rate of global warming compared to Valentia Observatory.

This suggests that despite all the care taken with the CET construction by various authors, the raw data avalable must have been too pervasively contaminated by urban warming to adequately correct.

To see the 1869-1999 trends for these two stations clik here.

Clearly there is not much "global warming" happening in this region going by Valentia Observatory.

You read it first here

Updated 21, August, 2000