Stop the climate change propaganda
Letter to the Editor
Issue date: 2/7/08 Section: Viewpoint
Professor Darcia Narvaez makes a statement in her column ("A call to conserve," Feb. 5) that manmade global climate change will be "profoundly affecting the survival of most if not all planetary life forms" if immediate action is not taken to stabilize emissions of greenhouse gas equivalent. That climate change could cause the extinction of most or all species on the planet is a very frightening prospect, to be sure, but is it grounded in fact?
A cursory survey of available evidence from previous climactic shifts, 20th century warming and studies on the effects of warming on species reveal that the professor's statement is actually nothing more than fearmongering.
First, consider the observations from the 20th century. If climate change will cause unprecedented extinctions across all variations of life, then one would expect that the 0.7 degrees Celsius of warming observed empirically in the 20th century would have definitively caused at least a few extinctions.
However, a Chris D. Thomas survey in 2004 found that global climactic shifts have caused one extinction (that of the Golden Toad of Costa Rica). That global warming should be implicated in so few extinctions is surprising, especially when one considers that Thomas' survey actively sought to implicate global warming in extinctions.
Furthermore, some evidence suggests that even that estimate may have been an overestimate. If warming has caused at maximum one extinction in the 20th century, claims that warming this century will threaten all life on Earth are highly suspect.
Secondly, to state that manmade warming will threaten the very existence life on the planet is inconsistent with historical data. Most species extant today have existed for at least one million years, and during this period species had to endure climate events ranging from the Holocene Climate Optimum (with temperatures warmer than IPCC estimates for 2100) to the ice ages to the shutdown of the Gulf Stream.
A cursory survey of available evidence from previous climactic shifts, 20th century warming and studies on the effects of warming on species reveal that the professor's statement is actually nothing more than fearmongering.
First, consider the observations from the 20th century. If climate change will cause unprecedented extinctions across all variations of life, then one would expect that the 0.7 degrees Celsius of warming observed empirically in the 20th century would have definitively caused at least a few extinctions.
However, a Chris D. Thomas survey in 2004 found that global climactic shifts have caused one extinction (that of the Golden Toad of Costa Rica). That global warming should be implicated in so few extinctions is surprising, especially when one considers that Thomas' survey actively sought to implicate global warming in extinctions.
Furthermore, some evidence suggests that even that estimate may have been an overestimate. If warming has caused at maximum one extinction in the 20th century, claims that warming this century will threaten all life on Earth are highly suspect.
Secondly, to state that manmade warming will threaten the very existence life on the planet is inconsistent with historical data. Most species extant today have existed for at least one million years, and during this period species had to endure climate events ranging from the Holocene Climate Optimum (with temperatures warmer than IPCC estimates for 2100) to the ice ages to the shutdown of the Gulf Stream.