Saturday, December 06, 2008

Four harsh truths about climate change


Gwynne Dyer: Four harsh truths about climate change
By Gwynne Dyer
Food will be the key issue as temperatures rise more quickly than expected.

About two years ago, I realized that militaries in various countries were starting to do climate-change scenarios in-house—scenarios that started with the scientific predictions about rising temperatures, falling crop yields, and other physical effects, and then examined what that would do to politics and strategy.

The scenarios predicted failed states proliferating because governments couldn’t feed their people; waves of climate refugees washing up against the borders of more fortunate countries; and even wars between countries that share rivers. So I started interviewing everybody I could get access to, not only senior military people but scientists, diplomats, and politicians.

About 70 interviews, a dozen countries, and 18 months later, I have reached four conclusions that I didn’t even suspect when I began the process. The first is simply this: the scientists are really scared. Their observations over the past two or three years suggest that everything is happening a lot faster than climate models predicted.

This creates a dilemma, because for the past decade they have been struggling against a well-funded campaign that cast doubt on climate change. Now, finally, people and even governments are listening. Even in the United States, the world headquarters of climate-change denial, 85 percent of the population now sees climate change as a major issue, and both major presidential candidates promised 80-percent cuts in American emissions of greenhouse gases by 2050.

The scientists are understandably reluctant at this point to announce publicly that their predictions were wrong, that it’s really much worse, and that the targets will have to be revised. Most of them are waiting for overwhelming proof that climate change really is moving faster, even though they are already privately convinced that it is.

The second conclusion is that the generals are right. Food is the key issue, and the world food supply is already very tight: we have eaten up about two-thirds of the world grain reserve in the past five years, leaving only 50 days’ worth in store. A 1°C (1.8°F) rise in average global temperature will take a major bite out of food production in almost all countries that are closer to the equator than to the poles, and that includes almost all of the planet’s “breadbaskets”.

So the international grain market will wither for lack of supplies. Countries that can no longer feed their people will not be able to buy their way out of trouble by importing grain from elsewhere, even if they have the money. Starving refugees will flood across borders, whole nations will collapse into anarchy—and some countries may make a grab for their neighbours’ land or water.

These are scenarios that the Pentagon and other military planning staffs are examining now. They could start to come true as little as 15 or 20 years down the road. If this kind of breakdown becomes widespread, there will be little chance of making or keeping global agreements to curb greenhouse-gas emissions and avoid further warming.

The third conclusion is that there is a point of no return after which warming becomes unstoppable—and we are probably going to sail right through it. It is the point at which anthropogenic (human-caused) warming triggers huge releases of carbon dioxide from warming oceans, or similar releases of both carbon dioxide and methane from melting permafrost, or both. Most climate scientists think that point lies not far beyond 2°C (3.6°F) hotter.

Once that point is passed, the human race loses control: cutting our own emissions may not stop the warming. But we are almost certainly going to miss our deadline. We cannot get the 10 lost years back, and by the time a new global agreement to replace the Kyoto accord is negotiated and put into effect, there will probably not be enough time left to stop the warming short of the point where we must not go.

So—final conclusion—we will have to cheat. In the past two years, various scientists have suggested several “geoengineering” techniques for holding the temperature down directly. We might put a kind of temporary chemical sunscreen in the stratosphere by seeding it with sulphur particles, for example, or we could artificially thicken low-lying maritime clouds to reflect more sunlight.

These are not permanent solutions; they are merely ways of winning more time to cut our emissions without triggering runaway warming in the meantime. But the situation is getting very grave, and we are probably going to see the first experiments with these techniques within five years.

There is a way through this crisis, but it isn’t easy and there is no guarantee of success. As the Irishman said to the lost traveller: “If that’s where you want to go, sir, I wouldn’t start from here.”




Gwynne Dyer
will be speaking on his new book, Climate Wars, at the Park Theatre (Cambie and 18th) in Vancouver on December 6 and 7 at 1 p.m. Tickets available from www.festivalcinemas.ca/ or at the door.

No comments: