Cities affect weather thousands of kilometres away
PARIS (AFP) - Heat from large cities alters local streams of high-altitude winds, potentially affecting weather in locations thousands of kilometres away, researchers said on Sunday.
The findings could explain a long-running puzzle in climate change: Why some regions in the northern hemisphere are strangely experiencing warmer winters than computer models have forecast.
Cities generate vast amounts of waste heat, from cars, buildings and power stations, which burn oil, gas and coal for transport, heating or air-conditioning.
This phenomenon, known as the "urban heat island", has been known for years, but until now has mainly been thought to affect only city dwellers, especially in summer heatwaves.