Another climate change denier myth - this one a favorite of Anthony Watts and his "Watts Up With That" blog - has just bit the dust.
Many skeptics for years have sought to explain away decades of climate research by showing slides of weather station thermometers sited next to heating vents or surrounded by asphalt.
This much-touted "urban heat island effect" was supposed to trump all those fancy graphs and equations that egghead scientists were fixated on. Except it’s not true.
A recent peer-reviewed paper in the Journal of Geophysical Research looked at data from 114 weather stations from across the US over the last twenty years and compared measurements from locations that were well sited and those that weren’t.
They did find an overall bias, but it was towards cooling rather warming.
According to the authors,
"the bias is counter intuitive to photographic documentation of poor exposure because associated instrument changes have led to an artificial negative ("cool") bias in maximum temperatures and only a slight positive ("warm") bias in minimum temperatures."
Oops.
MORE:
http://www.dailykos.com/story/2010/1/22/143650/988?new=true