A strong warning that global warming was under way was given in 2007 by the IPCC in a 'Summary for Policymakers'. (See p7 and fig. spm.5). It was also forecast that the average air temperature would rise by .2 degrees C per decade.

IPCC

A reasoned, and dissenting voice to the IPCC 2007 report is the website of Dr Syun-Idi Akasofu. Another sceptical voice is from the website wattsupwiththat.com

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Although there are some doubts about the average air temperatures at various heights, the global sea surface temperatures are a better indication of global heat changes, and these show more of a definite increase, and the global sea levels since late 1992 have also definitely risen. The oceans absorb carbon dioxide from the atmosphere, and have been absorbing extra amounts as the levels of that gas rise - and causing the seas to be more acidic. It's not known how much more the oceans can act as a 'sink' in this way, and there are implications for the survival of marine life in a more acidic environment. Also to be considered is the question of whether there are more extreme weather events occuring and whether this is related to excessive greenhouse gases in the atmosphere.

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The website climate4you.com has been created in order to present information in as scientific and unbiased way as possible, and it's definitely worthwhile to spend some time going through the site.

Prof. Ole Humlum, University of Oslo

Although there is seasonal variation, the answer is yes. However the extent of the Antartic ice is increasing, and quite rapidly too, and if the two effects are put together there isn't much overall increase or decrease. For facts and figures, go to climate4you.com, and for a discussion, on a site that is sceptical about whether climate change is really happening - go to wattsupwiththat.com

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