There relationship between greenhouse gases, aerosols, and climate sensitivity is much more complex... Photo: Codo via flickr.
While there may be consensus among mainstream scientists that climate change is definitely happening, and that human activity is responsible for it, the science is undoubtedly complex and research continues to refine our understanding of all the different elements of the equation. BoingBoing points out that one onging discussion is about how sensitive the climate is to increases in CO2. It makes a difference to both climate models, as well as what we can do to prevent further temperature increase:Gavin Schmidt at NASA's Goddard Institute for Space Studies reminds us that climate scientists "aren't idiots just going around looking at CO2, CO2, CO2. There are many different drivers of climate, including ozone and aerosols. We've only just started to relate these things to the policy choices that real policy makes are faced with."
Some Aerosols Mask Warming, Some Increase It
TreeHugger has covered the growing realization among scientists that aerosols have a great role to play in global warming, more than was previously believed, on a number of occasions. Depending on what type of aerosol you're talking about it can actually mask warming, or accelerate it. And in the case of black carbon (soot to you and me), when it falls on glaciers, it can actually speed up melting of those as well.
If the aerosol cooling influence is a small fraction of the greenhouse gas influence then the observed warming is obtained with rather low climate sensitivity. If the aerosol influence is offsetting a large fraction of the greenhouse gas influence, it implies a fairly high climate sensitivity.
As BoingBoing correctly sums it up, for humanity that difference in sensitivity changes how quickly we have to act to prevent greater temperature increases, or whether we can do anything at all to stop them.
Read more: BoingBoing
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