Posts Tagged ‘antarctic’

Global sea ice

Thursday, May 8th, 2008

One measure of world temperature that is relatively objective is the total amount of ice. It is hard to measure average world temperature precisely, hard even to say what such an average means, and those that claim to measure it with great precision over great periods of time are liars, but ice, ice is a fact.

And so, from time to time, one gets an anthropogenic warming story, “Oh no the ice is melting”.

Another Record Arctic Ice Melt Expected This Summer

Whenever you read such a story, check the total amount of ice. It does not change much, and has not changed much. Some times it goes up a bit, sometimes down a bit. When ice melts dramatically in one place at one time it usually freezes up in another place not very long afterwards. Today, it is pretty much the same as ever it was.

Which very much suggests that the world’s temperature has not changed much – that global warming, whether anthropogenic or not, is so small as to be unmeasurable compared to ordinary year to year and decade to decade fluctuations.

We have not had a really good direct measure of global temperature until the Aqua satellite was launched. And since the Aqua satellite was launched, we have had no “global warming”.

Before Aqua, the best way to estimate changes in global temperature was to look at proxies such as total ice coverage – and the proxies have been telling us that nothing much has changed.