Thursday, May 24, 2007

Warm, Warmer, Warmest

From the New Scientist, a special report on global warming.

A firm and ever-growing body of evidence points to a clear picture: the world is warming, this warming is due to human activity increasing levels of greenhouse gases in the atmosphere, and if emissions continue unabated the warming will too, with increasingly serious consequences.

Yes, there are still big uncertainties in some predictions, but these swing both ways. For example, the response of clouds could slow the warming or speed it up. With so much at stake, it is right that climate science is subjected to the most intense scrutiny. What does not help is for the real issues to be muddied by discredited arguments or wild theories.

So for those who are not sure what to believe, here is our round-up of the 26 most common climate myths and misconceptions.
I've only read a few of the articles, but what I've seen has been very, very good, like this riposte to the "It's too cold where I live - warming will be great" line that gets trotted out here in Minnesota:
As global temperature climbs to 3°C above present levels - which is likely to happen before the end of this century if greenhouse emissions continue unabated - the consequences will become increasingly severe. More than a third of species face extinction. Agricultural yields will start to fall in many parts of the world. Millions of people will be at risk from coastal flooding. Heatwaves, droughts, floods and wildfires will take an ever greater toll.

There are two factors should borne in mind when thinking about the impacts. Firstly, even countries that escape the worst of the direct effects will feel the economic effects of what happens elsewhere. There may be social and political problems too, as migration increases and water becomes increasingly scarce in some regions.

Secondly, there are time lags between rises in CO2 and their impact on climate... The IPCC [Intergovernmental Panel on Climate Change] predicts a minimum temperature rise by 2100 of 1.8°C... - more than enough to inundate many major cities around the world, including New York, London and Sydney.
So, yeah, while we might be able to start making (more) mediocre wine here, that's a bad tradeoff for seeing New York go under water, not to mention the low-lying cities in Asia that house millions of our fellow humans.