Wednesday, May 09, 2007

Climate change as a 'normal' problem

Of course we can fix climate change. How? Well, what's the difference between the way we live now and scraping a living hunting-and-gathering? The answer is technology.

Looks like it's getting too warm? Take a look at the following (from the Guardian, here).

"Stephen Salter, the innovative Edinburgh University engineer, (known best for his invention of Salter's duck - the 300-tonne floating canister designed to drive a generator from the motion of bobbing up and down on waves) thinks he has the key.

"We need to atomise seawater and throw tiny droplets into the air," he says. The idea is that this fine mist of sea-spray evaporates, leaving tiny particles of sea salt that get sucked up into marine stratocumulus clouds on rising currents of air. These little particles act as centres for extra droplets to form. "Clouds become more reflective if you increase the number of droplets in them," explains Latham. A bonus of filling the clouds with smaller droplets is that they tend to last for longer, reflecting more sunlight back into space, before they disperse.

To produce this fine mist of sea spray artificially, Salter envisages thousands of unmanned yachts zigzagging across the sea, carrying equipment to make very choppy waves, known as Faraday waves. A high-frequency ultrasonic generator would spin seawater around inside a grooved drum, producing tiny waves that are thinner than a human hair. "It looks a bit like a cup of coffee on a rattling train, but it would be nearly vertical," says Salter. Once the waves are steep enough, drops of water are thrown up from their crests. "All we need to do is try and get these fine droplets into the first few metres of air, and meteorology will do the rest," says Latham.

To remain truly environmentally friendly, the yachts would be driven by wind acting on the spinning drum, like a sail. Movement of the boat through the water would drive propellers acting as turbines, to produce the electrical power for spinning the drums and driving the ultrasonics. Meanwhile, satellites would direct their movements, placing the yachts in the areas of ocean where the most effective stratocumulus clouds could be modified.

But would it really work? If calculations and computer models are to be believed, then yes, the physics of this idea is sound. Working together with Tom Choularton, of Manchester University, and Mike Smith, of Leeds University, Latham has done extensive calculations to make sure he has got his sums right. In addition, they have tested the idea using the Meteorological Office's Global Climate Model and shown that increasing the droplet numbers in marine stratocumulus clouds could have a significant effect. "Modifying an area covering around 3% of the Earth's surface produced a cooling that more or less balances the warming from doubled carbon dioxide levels," says Latham."

Assuming that the current round of global warming is actually CO2 driven, and is not affected by other factors, such as solar activity variability, this seems like a good investment to me. And more likely to work than Kyoto round two. Especially if there is an additional cause beyond the CO2.

I'm personally more concerned about the next ice-age (well, intellectually-personally, not personally-personally of course). Can technology solve this problem, as the glaciers march south through Scotland?

Imagine a concrete wall a mile high. A gigantic V with the point facing north, prising the encroaching ice apart and shoving it into the Irish and North seas. The wall is kept warm, lubricating ice-flow, by embedded heating from our fusion power stations. Cheap fusion power keeps things balmy in the rest of England (probably using He3 mined from the moon - ref here).

I like to think Hadrian would have approved!

NOTE: for readers growing tired of the relentlessly frivolous and depressingly jaunty tone of recent posts, I would confirm the serious point of the above to be simply this.

Climate change is certainly a problem of some priority for humanity. This would seem to suggest we employ the usual rules for problem qualification, solution generation and assessment, and economic ('business case') underpinning for whatever we intend to do about it. Hijacking the issue in moralistic, quasi-religious terms is just about the stupidest possible response, in the technical sense of using the most primitive parts of our brains to address the issue...