photo: Lisamarie Babik via flickr.
And just when you thought things couldn't get worse... The UK's Met Office has just released a new assessment of how much temperatures will rise by 2100 if greenhouse gas emissions go unchecked and it's really not pretty. Without strong curbs on emissions global average temperature rise could exceed 4°C by the end of the century, with some areas seeing much, much higher increases:Arctic Warms 15 Degrees, Africa is 10 Degrees Hotter
The report shows that the Arctic could warm by up to 15.2°C under high-emissions scenarios. This temperature rise being pushed on by more of the sun's radiation being absorbed as snow and ice melt accelerates.
In Africa western and southern regions could see average temperature rises of 10°C.
Though the study shows that rainfall could increase by as much as 20% in some places (in particular in parts of India), in all the scenarios western and southern Africa, Central America, the Mediterranean and coastal Australia all see decreases in rainfall.
Comparison of surface temperature projections from the high-end emission scenarios, without carbon cycle feedbacks, presented in the Met Office report. Image: Met Office
Half of World Population Without Adequate Water
It's widely acknowledged that once temperature rise goes past 2°C things get pretty catastrophic -- a temperature increase of 4°C could threaten the water supply of half of the world's population, cause 50% of all animal and plant species to go extinct, not to mention cause low-lying areas to become submerged by the sea.
Worst Case Scenario = 4°C by 2060
Now here's the really bad part: Under the most extreme scenario that 4°C doesn't come a century from now, rather it happens by 2060 or 2070. Granted, that's the worst-case, but if there's a scarier climate change scenario than that, I haven't seen it.
We Can Prevent This...
Doom and gloom aside, Dr Richard Betts, who presented the findings at Oxford University, insists that there is a clear and effective way out: Cut greenhouse gas emissions and now!
It is possible to avoid these dangerous levels of temperature rise... If global emissions peak within the next decade and decrease rapidly it may be possible to avoid at least half of the four degrees of warming.
More: 4 Degrees and Beyond
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