Urban Heat Islands Make Cities Greener

[Ivan Seeking]

...from NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on the Terra satellite, Boston University, Boston, researchers discovered that city climates have a noticeable influence on plant growing seasons up to10 kilometers (6 miles) away from a city's edges. Growing seasons in 70 cities in eastern North America were about 15 days longer in urban areas compared to rural areas outside of a city's influence. [continued]

http://www.gsfc.nasa.gov/topstory/2004/0801uhigreen.html

[Andre]

Thanks for finding that. Unfortunately that link won't work. This one does:

http://earthobservatory.nasa.gov:8000/Newsroom/NasaNews/2004/2004072917348.html

Note:
Springtime land surface temperatures in eastern North American cities were on average 2.3°C (4.1°F) warmer than surrounding rural areas, according to the study. In late autumn to winter, the city temperatures were 1.5°C (2.7°F) higher than the surrounding areas.

Those numbers are not unfamiliar to me, as I was also studying the case. But they beat me to it.

So, how about the correlation between exponential growth of population, exponential growth of cities and exponential growth of Urban Heat Island effect on the Global temperature?