EPA's report to the United Nations says that global warming exists, that it is man-made, and that it will transform the environment. Likely effects in the U.S. include "the disruption of snow-fed water supplies, more stifling heat waves and the permanent disappearance of Rocky Mountain meadows and coastal marshes." But the report suggests that the U.S. will have to accept the changes, rather than take any action to try to avert them.
The U.S. climate action report can be found on EPA's Web site, www.epa.gov.