An Australian-led team of researchers reports that we've underestimated the heating effect of carbon dioxide emissions which suggests we're heading for a 4C future.
Report authors Steven Sherwood, Sandrine Bony and Jean-Louis Dufresne found climate models which show a low global temperature response to CO2 emissions do not factor in all the water vapour released into the atmosphere.
Models typically simulate water vapour as rising to 15km and forming clouds, rather than updraughts of water vapour that rise only a few kilometres and pull away the cloud-forming vapour.
This prediction of cloud cover is important because clouds reflect sunlight, lessening the impact of global warming.
The report, conducted between the University of New South Wales and the Université Pierre et Marie Curie in Paris, finds “real world observations” show the accepted models are wrong.
In reality, the study found, water vapour is distributed to different heights in the atmosphere, causing fewer clouds to form as the climate warms.
In turn, this increases the amount of sunlight entering the atmosphere, making the level of warming far more sensitive to heat-trapping gases such as CO2.
As a result, the world can expect a temperature increase of “at least” 4C by 2100 if, as predicted, there is a doubling of CO2 in the atmosphere. This could then rise by more than 8C by 2200.
Well we can't say we weren't warned. Whether future generations will have to endure climate catastrophe is a choice being made for them by you and by me today. Meanwhile, The Guardian's Myles Allen argues that our only way out of this carbon mess is to bury it.
The news appears to be worse than we imagined, Mound.
ReplyDeleteWe keep focusing on arbitrary timetables and artificial, even misleading limits. For example, we keep blathering about 2C by 2100 as though that's an accomplishment. It's not. Post-2100 those carbon emissions that brought us to 2C will continue heating the planet. That's why they warn that 4C by 2100 will transform into 8C by 2200.
ReplyDeleteWe need to start figuring out where we want mankind to be in 2400 or 2500 and what we need to do to achieve long-term goals.
Targeting 2100 just invites half-hearted efforts to buy time for us all to be dead and gone.
I can't imagine mankind will BE in 2400 or 2500.
ReplyDeleteAt the very least can we PLEASE shut down the tar sands and knock off all the fracking??
No? Then what can we do but dance.
http://climatenamechange.org/#/petition
ReplyDeleteA petition to name major storms after climate change deniers.
Not sure whether the "bury it" guy had a point or not, didn't read past this:
ReplyDelete"Being a physicist, not an economist, I also understand that reducing carbon emissions by a fraction is not going to solve climate change. Carbon accumulates in the climate system. So reducing emissions by 10% means we take 10% longer to reach any given threshold for dangerous climate change. To actually solve the problem, we need to reduce emissions to zero."
Apparently he's not a very good physicist or he'd have investigated enough to realize this is basically bullshit. Greenhouse gases are constantly entering and leaving the atmosphere, at different rates for different ones. To solve the problem, we need to be adding them in slower than they are leaving, ideally quite a bit slower. Zero isn't even a particularly relevant number. To solve the problem in any kind of reasonable time frame, we may actually need to reach a negative number--who knows? He clearly doesn't.
I haven't heard a lot of positive things about the state of or even genuine intentions behind carbon capture and sequestration technologies, which I presume are what he's talking about. We don't actually need these new pie in the sky technologies. Wind and solar work now. Energy conservation works now. If governments would fucking do them and quit fucking whining and squirming, we'd have the job mostly done by now. We can worry about CCS when we've got the carbon production problem mostly solved.
Given that CO2 is very persistent, I think we do have to decarbonize our economy until we come up with an effective means of carbon sequestration.
ReplyDelete