ONE TOWN SQUARE: at the intersection of peak oil, climate change, and land use

Even if we could freeze-frame the atmosphere as it is today, sea levels would still rise by 25 meters, says the latest study into the effects of climate change on melting ice sheets.

Predicted effects on US coastline assuming sea level rise of 2 metres (red) and 25 metres (yellow).

And here’s Europe.

Red is area affected by 2 metres of sea level rise. Yellow shows 25 metres of sea level rise, which will take a couple thousand years

Of course, that’s in the year 4000, 2,000 years from now. So why worry?

Albert Bates has a great piece at Energy Bulletin titled “Summer Solstice in Tennessee” about how the climate in southern Tennessee is already changing – and not for the better.

Here in the bottom of Tennessee, where the next county south is in Alabama, we have been watching the summers grow steadily hotter. When we arrived here, a band of ragtag hippies in 1971, the climate wasn’t as bad as rumors would have it. . . . The climate we had in 1971 is now up near Lexington, Kentucky. The local summer heat of ‘09 was what folks down in Nashoba County, Mississippi, had regularly in 1971. . .

Since 1970 our average temperature in this region has risen 2 degrees, which is roughly the same change for the Southeast as occurred between now and the last time glaciers extended below the Great Lakes. So, just to begin with, 2 degrees is huge. It is the difference between southern Mississippi and Nashville, Tennessee. Trying to grasp what “about 4.5°F by the 2080s” will mean, never mind 9°F… fuggeddaboudit.

Bates quotes from the new federal report on “Global Climate Change Impacts in the United States:

The number of very hot days is projected to rise at a greater rate than the average temperature. Average temperatures in the [Southeast] region are projected to rise by about 4.5°F by the 2080s, while a higher emissions scenario yields about 9°F of average warming (with about a 10.5°F increase in summer, and a much higher heat index). . . Because higher temperatures lead to more evaporation of moisture from soils and water loss from plants, the frequency, duration, and intensity of droughts are likely to continue to increase.

and adds, that’s just the half of it. Higher temperatures, and higher nighttime temperatures, mean that some crops will no longer be able to be grown:

If summer rains and the groundwater or rivers dry up, it will be hard to sustain field crops. If it is consistently above 95°F, corn will not generate ears, or the kernels will wilt on them. Above 102°F, soybeans will not set bean pods, or the seed will shrivel and die. Even our shiitake logs will lose the mycelium that makes the mushrooms grow. . . Snap beans will fail if nighttime temperatures are consistently above 80°F.

Bates reports that forests are already succumbing:

We are already watching our hardwood forests fall of their own accord. Last year it was the oaks. This year it’s the hickories. Loblolly pine, a species that favors the sandy soils of Mississippi, was planted abundantly back in the late 1970s, when we worked as tree-planters and had lots of leftover stock, and also the forest service and ag-extension agents gave them away for free. Those are now thriving, happy to have the climate they most favor come their way. Loblolly will now move up into Kentucky, Pennsylvania, and New York, even as the sugar maples, spruce, beech, and wild plum go extinct.

As Bates points out:

Already droughts are becoming more common, forest fires spreading, lakes shrinking, and coastal storms increasing. Still, they may still be able to make a bean crop there by mid-century.

The most affecting passages describe the human discomfort and even bodily dysfunction resulting from higher temperatures. Bates points out that average temperatures are deceptive – what really hits hard are the extremes. He suggests that migration may be an option – it may prove to be the only option.

By the time lands in the southeast are lost to flooding, they may not have been habitable for hundreds of years, anyway.