Agreed. The Antarctic ice cap is never static.

However, what is concerning climate scientists is the comparitively very rapid change in both the Arctic and Antarctic ice caps that is occurring now.

I am not suggesting that the reported melting of this part of the Antarctic ice cap is definitive proof that elevated atmospheric greenhouse gas levels is responsible for global climate change. It is however further evidence added to a huge body of data and computer modelling that does indicate that a strong link exists.

Whether human activity (burning of fossil fuels and deforestation) is the primary or secondary driver behind global climate change is even more difficult to prove, as the original post stated. But even if there is only a small probability, say less than 30%, that humankind is the main driver behind climate change, then surely there is still sufficient justification for all governments, organisations and individuals to take measures. The consequences of denial are too scary to contemplate.

Australia's new government has accepted that the risks of denial are very real. One of its first moves was to ratify the Kyoto Agreement, and make a long term commitment to reduce national greenhouse emissions by 60% (of 1990 levels) by 2050. It is also planning on introducing a carbon trading scheme in 2010. Australia has a high per capita greenhouse emission, although in absolute terms we contribute less than 2% of global greenhouse emissions.

We are in this together, in the one life boat, and the future looks pretty rough.