Political Cortex: Brain Food for the Body Politic

Scientists from the American Geophysical Union, Centre for Ecology and Hydrology Dorset and Wageningen University, will have a paper in this week's Geophysical Research Letters. The gist of that paper:

A team of Europeanc scientists reports that climate change estimates for the next century may have substantially underestimated the potential magnitude of global warming. They say that actual warming due to human fossil fuel emissions may be 15-to-78 percent higher than warming estimates that do not take into account the feedback mechanism involving carbon dioxide and Earth's temperature.

 According to this study, the results of greenhouse warming may actually push Earth toward a feedback loop that encourages more global warming.  Greenhouse gases cause warming, and warming may itself cause more greenhouse gases, causing yet more warming, and...

It's unlikely we'd slide completely into the Venus trap  (where greenhouse gases push the surface temperature above 800 degrees F), but we can get pretty darned warm.  At several times in the past, Earth has been warm enough that there were no ice caps at the poles, or glaciers anywhere on the planet.  So when the right talks about global warming as "representing no threat to the planet," they're completely right.  Earth won't end because of global warming.  It's highly unlikely that life will be threatened.  Civilization... eh, maybe.  Our current social and political structures?  Definitely.

If this was a single report, it might be dismissed an overly cautious look at the problem, but this report isn't the only recent hint that global warming is coming on harder than many expected.  A  new report by the Australian government is equally frightening.

Global warming could be happening faster than scientists had previously thought and weather extremes such as heatwaves could become common, an Australian government report said on Tuesday.

The report by the Environment Department said there was a greater risk that global warming could now exceed previous predictions of a 1.4 to 5.8 degrees Celsius rise in temperatures by the year 2100.

The Australian report also states what many have speculated about since the active 2005 hurricane season and it's horrible consequences -- global warming means more storms, and more powerful storms.

Warmer sea surface temperatures lead to more moisture and heat in the atmosphere, fuelling storms. But a warmer world can also lead to more intense droughts, threatening the livelihoods of millions around the globe.

The report said climate change might be making hurricanes and typhoons more destructive, though not necessarily more numerous.

If values changed by that top number (around 10 degress F), it would mean an enormous shift.  Plant hardiness zones would move upward by two or more levels meaning you could grow oranges in Atlanta.  Maine might enjoy a climate closer to that of North Carolina.  Which would be nice... except much of Maine might not be there to enjoy it.

As recently as 2005, studies indicated a sea level rise on the order of less than three feet over the next century.  That's enough to spell disaster for many coastal cities (and hundreds of millions of people), but just as with temperatures, it now appears we may have underestimated sea level changes.  The melting of the Greenland ice sheet alone ould mean a 20 foot rise in sea levels, and with the current rate of melting in Greenland, that rise could happen much sooner than 2100.

Still not scared?  Then how about this report that features a Dutch-German team and another team from Berkley.  Their findings?

... as much as 2 degrees Celsius (3.6 degrees Fahrenheit) more warming by the end of the century than previously forecast, raising maximum estimates of total warming from about 10.4 to 13.9 degrees Fahrenheit, according to the Berkeley team.

That kind of rise would see the Earth warmer than it's been since the mid Cretaceous, more than 100 million years ago -- and one of those "ice free" periods.

Recognize this place?  It's the Gulf coast of the United States after a 10' rise in sea level.  The basic shape looks fairly familiar, and from this landmark-free version of the map, you can be forgiven for thinking not much has changed.  Here, try this version.

Those little dots give an inidication of just how far the coastlines would shift from this rise.  All the cities along the coast would be not just inundated, but out to sea.  New Orleans and Miami would be over a dozen miles from the nearest dry land.  That's what ten feet means.  The monetary losses are inestimable.

You saw the devestation caused by Katrina.  you saw the panic, the loss of life, the shift of populations, and the tremendous costs.  Now look at that map again.  Can the US survive that?  Add in the great coastal cities -- east and west -- being swamped one by one and battered by intense storms.  Add in the interior of the country overrun by drought, a return of the dustbowl, as deserts replace farmlands.  

Oh, and remember that those maps above are a ten foot rise.  Make it twenty, and half of Florida is gone, along with another large slice of the coast.  If those predictions of a > 10 degree increase are correct and the poles completely loose their ice, there's a much, much larger sea level rise in our future.  A rise that could erase the whole state of Florida and bring coastline to Arkansas.

Earth will survive, the right wingers are correct about that much, but Earth is tougher than societies and nations.