MAY 2009
CONGRESS OF THE UNITED STATES
CONGRESSIONAL BUDGET OFFICE
CBO
Potential
Impacts of
Climate Change
in the
United States
Pub. No. 3044
A
P A P E R
CBO
Potential Impacts of
Climate Change in the
United States
May 2009
The Congress of the United States O Congressional Budget Office
Note
The cover image was provided courtesy of the National Aeronautics and Space Administra-
tion’s Visible Earth team, http://visibleearth.nasa.gov.
Preface
Human activities are yielding rising atmospheric concentrations of greenhouse gases
and other gases and particulates and are also greatly altering the Earth’s land cover. A scientific
consensus has emerged that those activities, if allowed to continue unabated, will have exten-
sive, highly uncertain, but potentially serious and costly impacts on regional climates and
ocean conditions throughout the world.
This Congressional Budget Office (CBO) paper—prepared at the request of the Chairman of
the Senate Committee on Energy and Natural Resources—presents an overview of the current
understanding of the impacts of climate change in the United States, emphasizing the wide
range of uncertainty about the magnitude and timing of those impacts and the implications
of that uncertainty for the formulation of effective policy responses. The analysis draws
from numerous published sources to summarize the current state of climate science and
provide a conceptual framework for addressing climate change as an economic concern. In
keeping with CBO’s mandate to provide objective, impartial analysis, the paper makes no
recommendations.
Robert Shackleton of CBO’s Macroeconomic Analysis Division wrote the paper under the
general supervision of Robert Dennis, Douglas Hamilton (formerly of CBO), and William
Randolph. CBO staff members James Baumgardner, Juan Contreras, Terry Dinan, Rob
Johansson, Joseph Kile, David Torregrosa, Christopher Williams, and Thomas Woodward
provided valuable comments and assistance, and Holly Battelle and Adam Weber provided
research assistance.
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