Changing political climate

Lost among the charges and counter charges about lost explosives during the last week of the presidential campaign, was a last-gasp attempt by the environmental community to impact the election. The assault came from Dr. James Hansen, director of the NASA Goddard Institute for Space Studies, who traveled to Iowa from his Manhattan home to charge that the Bush Administration is purposely ignoring growing evidence that sea levels could rise significantly unless prompt action is taken to reduce heat-trapping emissions from smokestacks and tailpipes.” And that “delay of another decadeis a colossal risk.”

Scary stuff if true; but is it? Dr. Hansen himself hasn’t always thought so. His own most recent research, in which he has argued mainly for quickly limiting emissions of methane, rather than CO2, contradicts this claim. Smoke stacks and tailpipes don’t emit methane; cattle and rice fields do.

It appears that Dr. Hansen’s speech in Iowa during the climax of the election is just the latest example of a willingness to change his scientific position depending on his perceived direction of the political winds. For example, Dr. Hansen told former Vice President Al Gore that he predicted high-end estimates of warming, and attributed that to emissions of CO2. More recently, Hansen has embraced lower-end estimates of warming, and suggested that we should control methane emission more than CO2. Yet policy that impacts every area of our economy should be set on sound science, not science that bends to the political winds.

Back to his current charge; is it accurate, are CO2 emissions causing sea levels to rise dramatically? He apparently bases his assertion on his own publication [Proc Nat’l Acad Sci 2004] that to preserve global coastlines, global warming must not exceed one degree Celsius. As sole support for this unusual claim, he cites his own recent article in the popular Scientific American [vol 290, pp 68-77, 2004].

All independent evidence, however, shows sea levels rising steadily – by about 400 feet in the past 18,000 years, since the peak of the most recent ice age. Significantly, empirical evidence has demonstrated that there has been no acceleration of sea level rise during the strong warming in the early 20th century. Evidently, warming leads to faster evaporation from the oceans and an increased rate of ice accumulation on the Antarctic continent – producing a drop in sea level that mostly offsets the rise from the thermal expansion of the oceans.

In addition, as is well known, prompt policy action (by cutting emissions of greenhouse gases in accord with the Kyoto Protocol) would lower the calculated temperature rise by 2050 by at most a tiny one-thirtieth of a degree C – too small to even measure.

Further, it is important to remember that President Bush did not “withdraw” from the Kyoto Protocol on global warming – as his critics so falsely claim. He simply has not submitted the treaty to the Senate for ratification; but neither did his predecessor, former President Bill Clinton. Clinton decided not to submit the treaty that was negotiated on his watch because the Senate at the time had voted unanimously against any treaty that would have such damaging economic consequences. That vote was unanimous, including the junior Senator from Massachusetts, John Kerry.

It’s hard to see how ‘prompt action’ of any kind could affect sea level. Dr. Hansen’s critique is disingenuous and not founded on science, and is a prime example of why it is important not to base important public policy decisions on any one scientist’s predictions.