New Global Warming Theory

By Cynthia Kirk

This is Bill White with the VOA Special English ENVIRONMENT REPORT.

Scientists have long believed that reducing carbon dioxide gas in the atmosphere is the best way to slow the warming of the Earth. But new research suggests that reducing other gases may be a more effective way to slow climate change.

The study was presented by American space agency scientist James Hansen and a team of scientists at NASA's Goddard Institute for Space Studies. They say that carbon dioxide levels have remained about the same during the past twenty-five years. Yet they say the average temperature of the Earth's surface has increased.

The researchers found that the combination of other so-called greenhouse gases traps more heat in the atmosphere than once thought. Such gases include methane, chlorofluorocarbons and ozone gases. The new research suggests that limiting carbon dioxide and other gases is the best way to prevent the Earth from getting too warm.

Carbon dioxide in the atmosphere traps heat and keeps it near the Earth's surface. It is produced by burning fuels that contain carbon such as coal, oil and wood.

Three years ago, one-hundred industrial nations signed an agreement designed to reduce carbon dioxide levels in the air by the year Two-Thousand-Twelve. However, many countries objected to the climate change treaty. They said efforts to meet the goals of the treaty would harm their industries.

The NASA scientists say more efforts should be made to limit the other gases. They say other greenhouse gases appear to trap more heat in the atmosphere than carbon dioxide. And technologies already exist to control most other greenhouse gases.

NASA scientists say reductions in methane, ozone and black carbon gases also would improve public health and agricultural productivity. And they say the cuts would help the world's climate and improve the air.

Representatives of industries most affected by restrictions on carbon dioxide welcomed the findings. But some scientists fear the study might be used to ease pressure on industrial nations that produce more carbon dioxide. Others say it might be used to pressure developing countries to do more to control the release of harmful gases. But most scientists agree that reductions are needed in all areas to prevent further global warming.

This VOA Special English ENVIRONMENT REPORT was written by Cynthia Kirk. This is Bill White.