From comments here and elsewhere the biggest criticism seems to be that the probe at Heathrow may be too sensitive - the spike that people seem to be worried about would not have been recorded with the old style Mercury-in-glass thermo. I think a solution could be a full article on on the Heathrow climate station is needed - where it is, what material is it made from, what instrumentation is used etc. Perhaps they could record something for the One show - send John Hammond and Carol Kirkwood down there together with someone, say Stephen Burt, from the CoL community, to let viewers make their own conclusions?