Setting Record Straight on Global Warming

In James Flanigan’s “Getting Serious About Earth-Friendly Energy” [June 24], there is an error in a passage near the end.

Flanigan wrote: “Climate change that will add 2.5 to 10 degrees to the Earth’s temperature over the next 50 years is already assured because of heat from past emissions that is stored in the world’s oceans.”

The inevitable warming is not as high as was stated. Our understanding is that 0.5 to 0.75 degrees Celsius more warming will occur in the next 50 years or so, even if there are no further increases in greenhouse gas concentrations, not the much larger temperature increase that was printed.

However, even if carbon dioxide emissions continue at their current rate (that is, they do not increase), atmospheric carbon dioxide concentrations will continue to rise. To cause carbon dioxide concentrations to remain constant would require about a 50% decrease in emissions.

If emissions of carbon dioxide and other gases increase, then concentrations will increase beyond the 0.5 to 0.75 Celsius level stated above. Calculations from scientists around the world of temperature increases of 2 to 5 degrees Celsius (in the next 100 years) are for this scenario.

Ralph J. Cicerone

Chancellor

UC Irvine

Irvine

(Chancellor Cicerone, a renowned atmospheric scientist, headed a recent study of global warming for President Bush.)