US farmland, forests can absorb greenhouse gases
Date: 24-Apr-02
Country: USA
Author: Christopher Doering
The process, called carbon sequestration, occurs when grassy crops and fast-growing trees remove carbon from the air and store it in soil or use it to grow roots, stems and leaves.
Gary Jacobs, co-director of the Energy Department's Oak Ridge National Laboratory, said researchers are trying to find the best, cheapest ways of carbon sequestration.
"There's a need to go out there on a large scale and discover the warts," said Jacobs, speaking at a National Academy of Sciences conference on global warming. Researchers need to pinpoint "what works, what doesn't and what drives people's behaviors," he said.
The United States is the world's largest emitter of greenhouse gases such as carbon dioxide. The carbon emissions from power plants and factories have been linked to global warming, which scientists warn could lead to massive flooding and rising ocean levels.
By the year 2050, as much as 250 billion tons of carbon could be captured from the atmosphere and stored in soil, Jacobs said. An average of 3.5 billion tons could be removed each year, up from about 2 billion tons currently, he said.
The United States currently generates an estimated 5.8 billion tons of carbon dioxide annually, according to the U.S. Energy Department.
Farming practices such as not tilling the land before planting can help the soil retain more carbon, yielding more productive crops.
The U.S. Agriculture Department estimates that the U.S. carbon sequestration market could swell to $5 billion per year by 2035.
Scientists are breeding trees that remove more carbon, and finding ways to store it longer and deeper in the soil so less farmland is needed for carbon sequestration.
Jacobs said farmers need to know that benefits such as better crop yields and less soil erosion outweigh the costs of carbon sequestration, and at an attractive price.
"Economics do indeed matter," Jacobs said.
Several bills have been introduced in Congress during the last few years, offering incentives to farmers who set aside land to absorb carbon.
For its part, the Bush administration unveiled in February a plan to reduce emissions of green house gases and offered economic incentives to make the plan attractive for businesses.
In addition to linking emission cuts to economic output, Bush's economic advisors have proposed a pilot program to measure greenhouse gas emissions and carbon sequestration.