Letter: Gore’s film should open the public’s eyes

Thursday, June 22, 2006 | 7:12 a.m.

In his June 19 letter about Roger Ebert's review of Al Gore's documentary "An Inconvenient Truth," Jon Dale Hollabaugh makes the interesting argument that temperature records of the Earth's atmosphere are statistically irrelevant because direct measurements have been made for only the past 300 years.

Fortunately, we have methods other than direct measurement for determining the history of atmospheric temperature. Most significantly, ice cores from Greenland and Antarctica contain climate records that extend back more than 400,000 years. The relative abundance of the oxygen isotopes O-18 and O-16 in the ice is proportional to the air temperature at the time the water precipitated. That's a fact.

Using this phenomenon and others, paleoclimatologists have reconstructed the history of Earth's climate in astonishing detail. Such studies show that the Earth's climate is very sensitive to processes occurring on the surface, such as fluctuations in the output of carbon dioxide due to volcanic activity, for example, or the burial of large quantities of plants in the fossil record.

A huge amount of scientific evidence has persuaded the vast majority of climatologists that the burning of fossil fuels by humans is rapidly warming the planet, and that we should be very concerned about it. It is a complicated problem with implications that extend far beyond the length of our political election cycle, so it is convenient for elected officials to ignore it. May Al Gore's film be the "tipping point" in public awareness, so that our policymakers begin to take it seriously.

Stephen M. Rowland, Las Vegas