Carbon storage would require vast forest tracts, report says
Brian Stempeck, Greenwire senior reporter
Managing forests to store carbon dioxide could offset a large portion of
U.S. greenhouse gas emissions, but a massive effort could require hundreds
of millions of acres and cost as much as technological climate-change
mitigation strategies, Pew Center on Global Climate Change researchers said
today.

Some trees flourish with higher levels of CO2, and policymakers have long
touted forest sequestration as a good option for offsetting future
greenhouse gas emissions. Under the Kyoto Protocol, for example, countries
with huge forest reserves expect to profit by selling carbon credits to
nations that fail to meet emissions reduction targets.

Because cost estimates of carbon sequestration policies range widely, Pew
researchers — led by Robert Stavins of Harvard University and Kenneth
Richards of Indiana University — took the results of all economic studies
on sequestration to provide a range of cost estimates for such efforts.

Sequestering hundreds of millions of tons of carbon would cost between $25
and $75 per ton stored, the researchers say in a new report. The price is
driven by several variables.

“There is little doubt that the most important factor affecting the cost of
forestry-based carbon sequestration in the United States is the cost of
land,” wrote Stavins and Richards. The price of forest and agricultural
products and the types of policies used to encourage sequestration would
have a major impact on the cost of future sequestration efforts.

To offset a fifth of U.S. emissions — about 300 million tons of carbon per
year — would take a massive commitment in both financial costs and land
use. It would cost roughly $7.2 billion per year and would require 148
million acres, an area roughly the size of Texas, the researchers said at a
news conference.

Richards said that the vast swaths of acreage discussed in the report can
be misleading and that sequestration is more feasible than it might appear.

“We’re talking about this area being spread around the United States,”
Richards said of a potential large-scale sequestration effort. As much as a
third of 1 billion acres used for crops and pasture could be deemed
unsuitable for agricultural uses, because of environmental issues or
infertile soil, he said. That land could be used for carbon management or
reforestation, researchers say.

Still, given the results of this study, a sequestration program could cost
as much as many other mitigation strategies, Pew experts said.

“On a per-ton basis, these costs are comparable to those estimated for
other climate change mitigation options such as fuel switching or energy
efficiency,” said Eileen Claussen, president of the Pew Center.
“Nevertheless, the results of this study indicate that sequestration can
play an important role in future mitigation efforts.”

Pew is also working on future studies to suggest ways to best implement a
large-scale sequestration effort.

A wide range of federal agencies, including the Agriculture Department,
Fish and Wildlife Service, and others, have all begun to encourage
landowners, farmers and private companies to engage in small scale carbon
storage efforts (Land Letter, Jan. 8, 2004).

Kevin Sloan
Fish and Wildlife Biologist
U.S. Fish and Wildlife Service
Mississippi Ecological Services Field Office
6578 Dogwood View Parkway
Jackson, MS 39213
601 321 1135 phone
601  965 4340 fax