Friday, January 08, 2010

Bad, badder, and baddest science

Fox News may have just published what will prove to be the stupidest science article of the year. Several science bloggers have already written about this, but the article is so wrong it deserves attention by a wider audience. This is the opening of the offending, and unsigned, piece:
The tremendous volcanic eruption thought to be responsible for Earth's largest mass extinction — which killed more than 70 percent of plants and dinosaurs walking the planet 250 million years ago — is still taking lives today.

Scientists investigating the high incidence of lung cancer in China's Xuan Wei County in Yunnan Province conclude that the problem lies with the coal residents use to heat their homes. That coal was formed by the same 250-million-year-old giant volcanic eruption — termed a supervolcano — that was responsible for the extinction of the dinosaurs.

Except for the fact that there is a high incidence of lung cancer in Xuan Wei, everything about these sentences is wrong.
  • The dinosaurs did not go extinct 250 million years ago; dinosaurs did not exist 250 million years ago. An extinction event did occur 250 million years ago. It is usually called the End Permian event. At that time, over ninety percent of all sea life went extinct, including the trilobites, and around seventy percent of all land species went extinct. Just as the extinction of the dinosaurs, 65 million years ago, cleared the field for mammals to evolve, the End Permian extinction cleared the field for dinosaurs to evolve.
  • Volcanoes do not make coal. Period.
  • The Permian was not ended by the eruption of a supervolcano. Supervolcano is the popular name for an extraordinarily large caldera collapse. These events pump enormous amounts of ash into the atmosphere. The land downwind from a collapse can be buried under hundreds of feet of ash, killing all life and probably causing some extinctions. Globally, the amount of ash that lingers at high altitudes is enough to cause a sudden drop in temperatures that continues for years. If the right background conditions are in place, it is enough to trigger an ice age.
  • The volcanic event that coincided with the End Permian extinction was the deposit of flood basalts in what is now Siberia. Flood basalts are lakes of lava that are deposited by slow-motion eruptions through a series of fissures that form over a large area, rather than single vents like more familiar volcanoes. Flood basalts events that can last millions of years. The flatlands of Eastern Washington are a flood basalt deposit that took over six million years to form.

The anonymous Fox News writer was trying to summarize a recent paper about a cancer cluster in a small area of southern China. The authors of the paper have discovered that the low grade coal used for cooking and heating in Xuan Wei contains a much higher amount of silica than coal anywhere else in the world. Exposure to crystalline silica, which most commonly comes from cutting and grinding rock, causes inflammation and scaring in the lungs, a condition called silicosis.

The coal used domestically in Xuan Wei comes from three seams that were laid down in the late Permian. The uppermost seam, the one that was laid down closest to the time of the Siberian flood basalts and the End Permian extinction, contains the highest amount of small grain silica. The researchers found that the silica was added to the coal after if formed, probably carried in by groundwater. As a source for the silica, they point to a local layer of flood basalts, the Emeishan basalts, which were laid dawn about ten million years before the End Permian extinction. natural erosion of these basalts would have made the ground water high in silica. Later the eruption of the Siberian basalts would have added silica to the atmosphere, which, carried by water, would have added more silica to the already silica rich coal.

The paper is a great piece of detective work aimed at locating the source of an extremely tight cancer cluster. The women of Xuan Wei get lung cancer at a rate twenty times the Chinese average. However, the solution to the mystery has nothing to do with supervolcanoes and nothing to do with dinosaurs. The mystery of how those got into the story probably has more to do with a scientifically illiterate intern trying to tie a fairly dry scientific paper to two far more exciting and popular topics. Chris Rowan has traced the lede sentence, to a press release issued by the American Chemical Association, with one very significant change. This suggests the possibility that the Fox writer did not read beyond the release and maybe the paper's abstract. Sadly, most of the people who read the Fox article will never know just how wrong it is.

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