A Critical Conversation on Climate Change ... - Green Choices

introduction – a new fossil fuel crisis 9And this is defi nitely the main cause of climate change?The United Nations’ Intergovernmental Panel on Climate Change,perhaps the most prestigious body of climate scientists ever assembled,concludes that most of the observed warming of the last 50 yearsis likely to be due to the increase in greenhouse gas concentrationsdue to human activities.But isn’t there a lot of controversy about that?Not much. The IPCC’s judgement is now supported by the US’s NationalAcademy of Sciences, Brazil’s Academia de Ciencias, China’sAcademy of Sciences, the UK’s Royal Society, France’s Académie desSciences, Germany’s Akademie der Naturforscher Leopoldina, India’sNational Science Academy, the Science Council of Japan, the Russia nAcademy of Sciences, Italy’s Accademia Nazionale dei Lince i, theAmerican Meteorological Society, the American Geophysical Union,Canada’s Royal Society and the American Association for the Advancementof Science. 9 There’s no dissent from it in any of 928 peerreviewedscientific essays on global climate change published between1993 and 2003. 10 And the few remaining contrary bits of evidence havebeen pretty much explained away over the last couple of years. For example,the oceans have warmed in a way that virtually rules out cyclicvariations in solar energy as an explanation. 11OK, give me the bad news. What happens if the world’s above-ground carbondump goes on overfl owing into the atmosphere?At some point the buildup of carbon dioxide and other greenhousegases in the atmosphere will change the climate catastrophically. Asbiologist Tim Flannery notes, ‘There is so much carbon buried in theworld’s coal seams [alone] that, should it find its way back to the surface,it would make the planet hostile to life as we know it’. 12 Combustionof even a substantial fraction of remaining fossil fuels – even afew more hundred billion tonnes – could be disastrous. 13How bad is the situation now?It’s hard to tell what the ultimate effects will be, because the extragreenhouse gas already in the air will have long-term effects, notall of which are evident today. Global average temperatures haveincreased by only 0.7 degrees Centigrade since the mid-1800s. Tobe sure, some changes often attributed to global warming are alreadynoticeable. For example, rainfall in mid- to high latitudeshas increased, Arctic communities are increasingly threatened bycoastal erosion and damaged hunting territories, Arctic sea ice and