Keep in mind that even the darkest blue areas indicate 1 or 2°C warming. The dark red is 15°C of warming.
I really love Google Earth layers as a communication tool, and here's a great new one, albeit on a grim subject. In the wake of the Met Office's forecast that if we don't cut emissions sharply by 2020, 4°C global temperature rise is likely (with up top 15°C in some places), New Scientist shows us just how hot things could get:
Note how much temperature rise occurs in the Amazon -- not quite the Arctic, but it's much, much warmer.
And in Russia and Central Asia...
The Google Earth layer also shows precipitation changes under an average of 4°C temperature rise. Again, notice the Amazon, and the Sahara.
Note what happens in Asia: Warmer and wetter, on the whole.
Bringing it back to the United States, note that Texas and the Great Plains get drier, with modest increases in precipitation in the Northeast and California. Other models show how this precipitation is likely to shift seasonally, as well.
What does these images mean for ecosystems?
Amazon Turns to Shrubland, Ravaged by Fires
According to Wolfgang Cramer from the Potsdam Institute, with 4°C of temperature rise you can kiss the Amazon goodbye -- with deforestation and forest fire affecting 83% of the region and 30% converted to degraded shrubland and mixed woodland by 2100.
Monsoon in Northern India Stops
Four degrees of warming also means the monsoons are thrown seriously out of whack. Anders Levermann, also from the Potsdam Institute, says that the monsoon will be a mix from year to year of extremely wet and extremely weak -- and in southern China and northern India could stop entirely.
Download the layer: Explore the 4 °C world in Google Earth
More detail on the effect on the Amazon, the monsoon: New Scientist
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