By Juliet Eilperin
Washington Post Staff Writer
Wednesday, May 28, 2008
Global warming is already affecting the nation's forests, water resources, farmland and wildlife, and will have serious negative consequences over the next 25 to 50 years, according to a report issued yesterday by the federal government.
The scientific assessment by the U.S. Climate Change Science Program, which was commissioned by the Agriculture Department and carried out by 38 scientists inside and outside the government, provides the most detailed look in nearly eight years at how climate change is reshaping the American landscape. The report, which runs 193 pages and synthesizes a thousand scientific papers, highlights how human-generated carbon dioxide emissions from burning fossil fuels have already translated into more frequent forest fires, reduced snowpack and increased drought, especially in the West.
Anthony C. Janetos, director of the Joint Global Change Research Institute of the University of Maryland and the Pacific Northwest National Laboratory, said the document aims to inform federal resource managers and dispel the public's perception that global warming will not be felt until years from now.
"They imagine all these ecological impacts are in some distant future," said Janetos, one of the lead authors, who noted that many animals and plants have shifted their migratory and blooming patterns to reflect recent changes in temperature. "They're not in some distant future. We're experiencing them now."
The document concludes that Americans must face the fact that many of these changes are locked in even if the country takes significant steps to cut emissions in the coming decades.
"Climate change is currently impacting the nation's ecosystems and services in significant ways, and those alterations are very likely to accelerate in the future, in some cases dramatically," the report says. "Even under the most optimistic CO2emission scenarios, important changes in sea level, regional and super-regional temperatures and precipitation patterns will have profound effects."
Richard Moss, vice president and managing director for climate change at the advocacy group World Wildlife Fund, said in an interview that the report represents "the very first upfront acknowledgment from the administration that we are already experiencing climate change impacts."
As recently as July 2007, the administration submitted a report to the United Nations that omitted any discussion of how global warming will affect wildfires, heat waves, agriculture or snowpack.
Moss, who led the U.S. Climate Change Science Program coordination office during both the Clinton and Bush administrations, praised the program for producing the analysis, which is part of a long-delayed series of official climate reports. "At the same time," he added, "we all need to be looking at how the administration now intends to use the results of this information, because it really is worrisome."
The researchers said that of 1,598 animal species examined in more than 800 studies, nearly 60 percent were found to have been affected by climate change.
In addition, the number and frequency of forest fires and insect outbreaks are "increasing in the interior West, the Southwest, and Alaska," while "precipitation, stream flow, and stream temperatures are increasing in most of the continental United States" and snowpack is declining in the West.
The Agriculture Department, the study's lead sponsor, issued a statement yesterday highlighting some of the report's findings for farmers, noting that the higher temperatures mean that grain and oilseed crops will mature more rapidly but face an increased risk of failure and "will negatively affect livestock."
"The report issued today provides practical information that will help landowners and resource managers make better decisions to address the risks of climate change," said Agriculture Department chief economist Joseph Glauber.
Agriculture Department spokesman William Hohenstein said the department is already incorporating climate change into all of its national forest management plans, and it is drafting a strategic research plan aimed at coping with global warming. "We will use this as a springboard in terms of identifying the questions we're going to focus on" for the strategic plan, he said of the report.
Peter Backlund, another of the report's lead authors and director of research relations at the National Center for Atmospheric Research, said in an interview that the Departments of Agriculture and Interior and other federal agencies will be tested by changing climate conditions on both public and private land.
"This is going to be a big challenge for agencies that haven't traditionally been big players in climate," Backlund said, adding the government's monitoring systems can chart major changes but are insufficient to serve as a climate warning system. "We lack the ability to identify the more subtle changes that are happening that could be much larger in the future. . . . We're pulling this information from systems that weren't designed to look at that."
The report predicts that some of the nation's most valued landscapes may change radically in the near future as precipitation and weather patterns continue to shift.
"Management of Western reservoir systems is very likely to become more challenging as runoff patterns continue to change," it states. "Arid areas are very likely to experience increased erosion and fire risk. In arid ecosystems that have not co-evolved with a fire cycle, the probability of loss of iconic, charismatic megaflora such as Saguaro cacti and Joshua trees will greatly increase."
One of the greatest challenges land managers will face over the next few decades, Janetos said, is uncertainty.
"You can't really assume anymore the climate is going to be familiar or similar to what we've seen over the 20th century," he said. "We're moving into new territory."