Monday, October 31, 2011

Climate Change

A reader has asked me to take on climate change.  I've been ruminating on how to approach the topic.  I'm not a climatologist in any sense, so there's not much that I can speak on about the science.  Not that I've let a lack of academic credentials bother me before.

But I think the primary issue I have is that I don't care.  Despite being an avowed leftist who attempts to think in terms of global systems, I don't care about global climate change.  There's not much I know about it.

Here's what I do know:

The Caspian Sea is shrinking.  This isn't purely academic, either.  The Soviet Union stored radioactive materials on an island there, where they'd be safely out of the way.  That island is now a peninsula.  It's not just now accessible from the mainland, it is the mainland.

Lake Chad is roughly half the size it was when it was first charted by Europeans.  The lake anchors the freshwater cycle of a great deal of West Africa.

The Sahara and Gobi deserts are growing.  The American West is getting drier.  Ranchers, farmers, and cities are squabbling over water levels in the Colorado River that drop year after year.  It's entirely possible that the West is coming out of a wetness peak unmatched for the last 40,000 years.

The Tigris and Euphrates valleys used to be a framing area so rich that it anchored the eastern end of the Fertile Crescent.  It's now largely desert and salt marsh.  North Africa was once the breadbasket of the Roman Empire.  It's now losing ground to an ever-growing desert.

The storied snows of Mt. Kilimanjaro are nearly gone.  Glacier National Park is losing its glaciers.  Continent long cracks are appearing in Antarctic ice shelves.  The Arctic summer is increasingly ice free.

Mean sea levels in Bangladesh and Micronesia keep rising.  By the 22nd century, both of those nations may perish from the face of the Earth.

All of this is local climate change.  Some is the result of warming, others the result of desertification. Is any relevant to the debate on "global warming"?  Maybe not.

But when you add up a lot of local climate change, don't you get a global climate change?

,,,
Let's talk a little bit about the carbon cycle.  No, not this oneThis one.  Here are the basics:

Plants grow.  Through a little miracle chemical called chlorophyll, they're able to absorb solar radiation and use that power to convert CO2 and H2O into various sugars.  This process releases O2 into the atmosphere.  Animals come along and eat plants and inhale O2, converting the starches in the plants back into CO2 and H2O and producing metabolic energy.


When everything is working properly, the two processes are more or less in balance.  Carbon dioxide enters the atmosphere, carbon dioxide leaves the atmosphere.  Life, literally, goes on.


The problem is, that oxygen really doesn't care for being alone.  It's a little kinky that way.  Sure, those two oxygen atoms don't mind being in a relationship together, but if they can grab a carbon atom and pull it on in, they'd be much happier that way.  Many current theories of planetary evolution suggest that terrestrial planets like the Earth tend to have atmospheres comprised largely of carbon dioxide and nitrogen.  It's a popular choice, just look at Venus and Mars.  

Earth is special.  Earth gets to have free oxygen.  By all rights, we should have a bunch of carbon in our air, much like our sister-planet, Venus.  But we don't.  That carbon is squirreled away somewhere.  Where'd it go?  Thank the plants (and their tiny friends, the cyano-bacteria).


It's true, animals eat plants, and so liberate carbon back into the atmosphere.  But not nearly as much as could be there, because a great deal of carbon is fixed into plant matter.  It's in the trees.  It's in the soil.  It's in the limestone.  And since trees enjoyed a several million year long success story on the planet, a lot of the carbon that was formerly trees is in the ground: coal.


Animals have been helping, to be sure.  Sometimes they die without giving up all of their carbons.  Sometimes, when animals and other non-tree sludge dies, it gets trapped underground.  It becomes oil.


Picture the Earth 100,000 years ago.  Tons of formerly atmospheric carbon is underground as coal and oil.  Tons more is built into wood and other plant matter on the surface.  Other carbon is moving through the ecosystem: air to plant to animal to air.  Everything is, to quote a recent decade, groovy.  There's a sense of balance.  Sure the pendulum swings from one extreme to another, from too much carbon in the air to too little.  But there are plans in place, too much free oxygen and you get more animals and more active animals.  Forest fires release carbon into the air.  Too much carbon, and plants grow faster.  Animals become lethargic and die off.  The pendulum swings back.


But then a buncha' monkeys come to a startling conclusion: "fire good."  Homo erectus tames fire, becomes adept at using it, lighting it, carrying it around.  Trees start to fall; carbon fixed in wood is liberated back to the air.  The monkeys start to have other bright ideas.  Trees are felled to build things.  Forests are cleared to create cropland.  Logs are feed to the flames.  Sure, a lot of the wood stays intact, keeping carbon out of the air, but with the loss of each tree is a loss of carrying capacity.  That tree will no longer scrub carbon from the air.  Whole continents are cleared of forests.  Easter is deforested to roll old statues around.  Minorca builds the Spanish treasure fleets.  The Black Forest feeds German industry.  Haiti kills its trees and wrecks its whole ecology and thus its economy.


Sure, a lot of trees give way to other plants.  But crops don't fix carbon: they grow and then are eaten.  Crops are essentially carbon neutral.  Grasses and grains aren't the carbon sinks the old forests were.


Then the monkeys get another bright idea: dig the carbon out of the ground.  Light it on fire.  Release it back into the air.  "What inspires in us this madness, that our existence should be defined / by a light that we can't see."   The plants do their best, but by now they're outnumbered.  The trees are dying.  Their maritime allies, the algae and cyanobacteria and other oceanic plant has been poisoned; many by the carbon drilled from the ground and allowed to spill across the sea by clumsy monkeys.  "We torch the Earth until it bleeds, rain ashes from the skies, just to make a light no one can see."


So the carbon climbs again into the sky...

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Googlebombing for a cause: www.minnesotangos.org

1 comment:

Doc Anne said...

"We torch the earth, set fire to the sky. We stoop so low to reach so high."
Who needs academic credentials? Sometimes they get in the way.