Curbing Energy Use Seen Delaying Greenhouse Effect
Vigorous efforts to cut oil, coal and natural gas use can substantially delay--but not stop--the warming of the Earth from the “greenhouse effect,” a study by an environmental group said Saturday.
“Depending on which policies are adopted, the year when we are irreversibly committed to a warming of (about 3 degrees to 8 degrees Fahrenheit) above the pre-industrial temperature varies by approximately six decades,” said the World Resources Institute, an environmental research organization based in Washington.
Although the planet is not locked into a hothouse future, “we no longer appear to have the opportunity to avoid a substantial greenhouse warming altogether,” the report warned.
Traps Radiation
The “greenhouse effect” occurs when gases in the atmosphere, most notably carbon dioxide, produced by burning fossil fuels, trap infrared radiation, warming the planet. As mean temperatures rise, weather patterns could shift, making most of North America and Europe drier. Sea levels would rise as the polar ice caps melt.
Scientists now believe carbon dioxide is responsible for about half of the increased warming and the rest is the result of other gases whose concentration is growing: methane, nitrous oxide, ozone and chlorofluorocarbons used in refrigeration and other activities.
The World Resources Institute reached its conclusion through a new computer model that incorporates all the major gases to predict the effects of policy changes under various assumptions. It contradicts an Environmental Protection Agency study from 1983 that said no policy could delay the warming of the Earth. That EPA study did not consider gases other than carbon dioxide.
The new study, by researcher Irving Mintzer, also contradicts a National Academy of Sciences study from 1983 that said there is plenty of time to decide what to do.
Mintzer said a 30-year delay in trying to counteract the greenhouse effect would add 0.45 to 1.44 degrees to the eventual temperature.
Sees Earlier Warming
Several studies have said a warming of 3 degrees to 8 degrees is inevitable by about 2030, and Mintzer predicted that much warming by 2025 if present trends continue.
An all-out effort to minimize warming by holding energy use almost constant could push the warming to sometime after 2075, the computer’s cutoff date. This scenario calls for a 31% to 37% reduction in per capita energy use.
Mintzer and other scientists said recent weather phenomena--rises in the Great Lakes, floods, extreme heat and droughts--were consistent with what could be expected from the greenhouse effect.
