Thursday, December 10, 2009

The Manchester heat island

Following on from our look at the heat island effect, we were pointed at a source of temperature data which included corrected and uncorrected temperatures for Manchester Ringway Airport.

The graph shown above (apparently from CRU) covers the period 1951 to 2001 and it can been seen that adjustments have made in the early period for a notional heat island effect, but the adjustments tail off from the 1990s, where there is hardly any difference between the two figures.

Yet, as can be seen from the two photographs, the difference between Ringway as it was in the early days (the top photo is undated, but looks to be late 40s early 50s) and Manchester International Airport as it is now. Yet the historic allowance is less than half a degree. This hardly seems enough, given the scale of the development.

The point that seems to escape many observers on this is that airfield weather stations are precisely that - weather stations. They are there to provide information to aviators, to enable them to fly safely. They are not and were never intended for long-term climatic research. Arguably, they should be excluded from the climate data sets.