Global Warming Could Make Water A Scarce Resource

By Cat Lazaroff

OAKLAND, California, December 15, 2000 (ENS) - Global warming could have serious impacts on water resources in the United States, and some of those effects are already being felt, a new report released today concludes. To counter those effects, government and water management officials must act now - a prescription that may be a hard sell under the new George W. Bush administration.

Those are the major conclusions of a two year study of the potential impacts of climate change on the nation's fresh and salt water systems.


Riggs Glacier in Glacier Bay, Alaska is typical of glaciers threatened by global warming. (Photo by John Bortniak courtesy of National Oceanic and Atmospheric Administration (NOAA))
"Water: The Potential Consequences of Climate Variability and Change," concludes that climate changes in this century may have serious implications for U.S. water resources. In fact, scientists are already observing changes in snow and rainfall, freeze and thaw dates and runoff patterns, attributable to global warming.

"Humans are changing the climate - the evidence is ... increasingly compelling," said Peter Gleick, president of the Pacific Institute and the lead author of the study. The study was jointly released today by the nonprofit Pacific Institute and the U.S. Department of the Interior.

The report offers the first opportunity for water managers to access information that can help them make long term policy decisions, said David Hayes, deputy secretary of the Interior Department.

"The report gives us both a positive and negative message," Hayes said. On the negative side, "yes, climate change is having important impacts" on "critically important" water and coastal resources.


Low lying areas like Jupiter Beach, Florida face flooding as sea levels rise. (Photo by Marge Beaver courtesy of NOAA)
"But it is not a 'sky is falling' report that merely paints a bleak picture," Hayes continued. "It gives us an opportunity to plan ahead."

The assessment caps more than two years of work by representatives of the government, corporate and non-governmental groups to evaluate the implications of both existing climate variability and future climate change on national water resources.

Scientists have determined that the buildup of greenhouse gases in the atmosphere over the past century, primarily from fossil fuel combustion, has contributed to a temperature increase of about two-thirds of a degree Celsius in the United States, with 1998 the warmest year on record.

The report concludes that this has already resulted in substantial thawing of the permafrost in the Alaska Arctic and unprecedented melting of mountain glaciers, an increase in sea level of between 10 to 20 centimeters, and an alteration of water runoff patterns as a consequence of decreased snow and ice cover and earlier melting.


High Alpine meadows like this one in Steamboat Springs, Colorado, could disappear as the Earth warms. (Photo courtesy High Meadows Ranch)
Climate models predict that temperatures could increase another three to six degrees Celsius by the end of this century. Warming of this magnitude could seriously affect U.S. water resources, the new report concludes.

Among the impacts outlined by the study are:

The study produced more than 40 new peer reviewed papers, and almost 1,000 more were evaluated and summarized. The report went through extensive external reviews, including reviews by the different assessment teams, a diverse advisory group, two separate formal external scientific review periods, and a 60 day public comment period.


Melting permafrost could affect birds that nest in the Alaskan Arctic tundra, like this long tailed jaeger (Photo courtesy Pacific Northwest National Laboratory)
Despite all the resources used to produce the report, the authors found they could not predict specific effects for particular regions with any degree of certainty. Although there are now a number of highly sophisticated models for predicting climate change effects, they often disagree about predictions on the regional level.

"Even if the models said the same thing we should be somewhat skeptical, because these models are not perfect," said Gleick. "We're very confident that the temperature is going to go up, and will continue to go up until we get a handle on our greenhouse gas emissions."

"This assessment was designed to be the first step," Gleick noted. "Our hope is that our ability to look at regional impacts will improve in the coming decades."

"We think there will always be uncertainty," said Gleick. But "not everything is uncertain," he noted. "We know enough now to take some actions."


Changing snowfall patterns could reduce the amount of runoff water from spring thaws available to fill reservoirs like Shasta Lake, behind the Shasta Dam in California (Photo courtesy NOAA)
Gleick emphasized the importance of water conservation and efficiency programs, and the need to look beyond traditional options for water supply options, such as dams and reservoirs to potential alternative sources of supply, including wastewater reclamation and reuse and desalination.

"Sole reliance on traditional management responses is a mistake," Gleick argued. "Water managers need to integrate possible climate change impacts into their planning processes and to build flexibility into the system to maximize our ability to respond to changing conditions."

Gleick emphasized the need to focus on measures to reduce the risks of climate change and to develop effective ways to adapt to the inevitable changes.

"Water managers should begin now assessing how their resources could be affected by climate change," said Gleick. "We're worried that if they don't start taking actions now, we're going to see the adverse effects of climate change hitting us."


Fish like these rainbow trout could be hurt by rising water temperatures and changes in the amount and timing of spring runoff (Photo courtesy Pacific Northwest National Laboratory)
"One of the conclusions I take form this report is that some of our assumptions about water availability for the future may be misguided," said deputy secretary Hayes. "Our country is now looking for water resources to be shared among competing needs, including environmental needs."

"We are on the threshold of some very major investments in water infrastructure throughout the country," Hayes said, citing the recently signed Everglades restoration bill, which promises to spend $8 billion dollars to reroute water within the nation's largest wetlands.

But that effort could be derailed before it is begun. "Rising sea level is going to be a challenge to the Everglades," said Gleick, a consideration which may not have been given enough weight in drafting the 30 year restoration plan. "It's a very important issue to the Everglades," because the largely freshwater wetlands are "very sensitive" to sea level rise.

The massive San Francisco Bay Delta restoration project, another pet project of the Clinton administration, could face similar difficulties, Gleick said. "They've not adequately looked at" sea level rise from global warming, he said.

Most climate change models project between half a meter to a meter of sea level rise over 100 years, an amount which may not appear to be very large at face value. But "the sea level rise we're talking about is faster than any sea level rise we've had to deal with in our civilization," Gleick warned.

"All of these efforts, as they proceed down a long path, need to now take a hard look at potential climate change impacts," said Hayes. "Climate change is the new kid on the block in terms of a new factor that ought to be taken into consideration."


Texas Governor George W. Bush, the nation's new President-elect, is expected to be less inclined to act quickly on climate change issues than the current administration (Photo courtesy Bush 2000)
However, the administration set to enter the White House in January may not give much weight to potential climate change effects. President Elect George W. Bush is on record as opposing the Kyoto Protocol, an international treaty aimed at reducing greenhouse gas emissions.

Bush has also said he believes that more data must be gathered before any action is taken to counter climate change.

"We're about to have a new administration in town that I'm afraid may not show the same sensitivity to this problem that the current administration has done," said Hayes.

Yet "part of this is independent of the next administration," noted Gleick. "I think no matter what, we're in for climate change. There is some unavoidable climate change coming. In that sense, it doesn't matter who the president is, or who the Interior secretary is."

"We do need to being to look at these things now, and if we don't the risk of surprise is greater," Gleick continued. "The risk of being blindsided is greater. It's really time to begin integrating these issues into our long term planning."

The full report is available at: