Saturday, September 19, 2009

Farm Animal Waste Contaminating Water Supplies


As the report, Moove that Manure, in Scientific American describes, manure from large farm animal operations can overwhelm the systems meant to contain or dilute it. The result is often contaminated surface waters and groundwater. This is but one symptom of the unsustainable system of agriculture we are growing in America and many other countries around the world.


In the farms of yesteryear, manure was not simply a waste product, but essential fertilizer. It enriched the soil for the next growing season, and helped prevent erosion and the depletion of soil fertility. The smaller and more diverse farms of that day could optimize their use of everything because they did not depend on the mass production of any one product.


But we don't have to return farming to what it was 50 or 100 years ago to make it once again sustainable. We may have to change our conception of a reasonable size for a farming operation, establish incentives that promote diverse agricultural businesses, and remove barriers that make it difficult for small farms to thrive. But we can do those things while still taking advantage of new technologies such as genetic engineering.

Thursday, September 3, 2009

Positive Feedback and the Runaway Greenhouse

Two recent reports about climate change research send up red hot flares warning of positive feedbacks promoting global warming.


The first is a report by Richard Kerr in Science magazine (see Kerr 2009) of research conducted by Amy Clement and colleagues at the University of Miami in Florida. The bottom line in this study finds that warming ocean temperatures may cause low clouds to thin, allowing more sunlight to reach the ocean and cause further warming of the ocean surface. In turn, this increased warming could cause further cloud thinning allowing even more sunlight to reach and warm the ocean. This positive, or reinforcing feedback provides one of the more frightening scenarios of climate change. The runaway greenhouse effect that a positive feedback loop could trigger threatens to make the worst predictions of the IPCC look tame.


The second report, by Charles Hanley of the Associated Press (see Hanley 2009), examines the findings of a host of permafrost scientists from Canada, Russia, the United States, Germany, Britain, Norway, and Sweden. The common thread here involves permafrost melting across the far northern hemisphere in response to rising temperatures. The danger lies with the large amounts of methane locked in the, until now, permanently frozen lands of the Arctic. If those lands thaw and release this methane, it would add significantly to the already dangerous greenhouse effect from the excess carbon dioxide we have added to the atmosphere since the beginning of the industrial revolution. Methane's greenhouse gas potential, molecule for molecule, is 21 times that of carbon dioxide. The release of even a fraction of the many billions of tons of methane locked up in the Arctic would cause a degree of increased warming sure to melt even more permafrost, and yes, you guessed it, release yet more methane. That should sound familiar, as it represents one more way that a positive feedback cycle threatens to produce a runaway greenhouse effect and catastrophic global warming.


And while climate scientists have been aware of both of these positive feedback possibilities for years, these new findings suggest that the possibilities may become reality. Both reports underline the need for continuing research, but both also point to a growing risk of extremely nasty climate surprises.


Climate skeptics are quick to point out that climate predictions may exaggerate the dangers of global warming. These two reports underline the fact that climate predictions may also greatly underestimate future global warming.

-------

Hanley, C.J. 2009. Climate trouble may be bubbling up in far north. News and Observer, Raleigh, NC. September 3, 2009 (Associated Press).

Kerr, R.A. 2009. Clouds appear to be big, bad player in global warming. Science 325:376.

Wednesday, September 2, 2009

Picturing Air


In the alternative energy video, "Kilowatt Ours", a resident of West Virginia laments the loss of a favorite mountain to mountain-top-removal coal mining. He recalls someone asking him if he had a picture of the mountain, and he replied that he did not, and for two reasons. First, it can be difficult to take a picture of a mountain since it is big and if you are close to or on it, how do you take a picture of it. Second, he lived on and around the mountain all his life, he never thought it would go anywhere, so why would he need to take a picture of it?


Similar difficulties face one wishing to take a photograph of the air. How do you take a picture of something that is all around you? Why would you take a picture of something that is ever-present?


Describing a hypothetical picture of air, one could mention it's oxygen content, temperature, water vapor content, water droplet density, carbon dioxide level, ozone concentration, particulate matter load, visibility or clarity, color, and the speed and direction of its movement. Some of these characteristics would show up in your image, some not, depending on their particular levels at the time.


How would you frame all of that?