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Freaky Weather & Water Loom
As Americans hunkered down through winter's showers, blizzards and blackouts, international scientists confirmed global warming as fact not fiction and a Bay Area think tank suggested that it was a mistake for water czars to think they can manage the droughts and floods of a warmer future the same way they have in the past.
"Adapting to climate change is going to come at a very high cost," says the Pacific Institute's Peter Gleick, lead author of the first really comprehensive, multi-agency national assessment of climate change impacts on U.S. water resources. The assessment, released in late 2000 through the U.S. Geological Survey, also examines impacts on coastal ecosystems, agriculture, forests and human health.
"Planning is cheap," says Gleick, "but here in California, for example, neither of the state's two major water planning efforts—CALFED and Bulletin 160—adequately address climate change. The guiding assumption of long term water planning continues to be that the future will look like the past, which is irresponsible."
Global warming watchdog Bill McKibben, author of The End of Nature, puts it a little more strongly. "In the worst case scenario, we'll see an 11 F° temperature increase in the next century. In all likelihood this means we will go through a total remaking of the external world that may look like anything from a horribly enormous environmental problem to science fiction, the freaking end of the earth."
The U.N. Intergovernmental Panel On Climate Change (700 scientists) projects a world surface temperature warming of 1.4 - 5.8 C° by 2100, and accompanying sea level rises of 0.09-0.88 meters as a result of melting ice. The National Assessment contributed to by Gleick suggests that the U.S. has already warmed by 0.6 C° since 1900, and that mean sea level has risen 10-20 centimeters since the 1890s.
"We're already seeing signs of climate change all over the nation — earlier snowmelts, higher temperatures, earlier migrations of birds and butterflies, plants blooming at different times," says Gleick. "In our own Bay-Delta region over the next 50 years, we'll be seeing salt water intrusion, changes in the timing of snowmelt and river runoff, Bay shorelines disappearing under water, and more extremes in terms of floods and droughts."
So why should water managers give a hoot? The National Assessment water report examined 1,000 peer-reviewed studies and concluded that there is compelling scientific evidence that climate change will pose serious challenges to our water systems; that it should be a factor in all decisions about water investments and the operation of existing facilities and systems; that rigid, expensive and irreversible actions (dams, reservoirs, aqueducts) in climate sensitive areas can increase vulnerability and long-term costs; that sole reliance on traditional management responses is a mistake; and that the more flexibility and adaptability to new extremes we can build into our waterworks, the better.
Global climate models provide few specifics on California impacts, but this February two U.C. Berkeley scientists completed some models that forecast serious water shortages for the state by 2049. Norman Miller and Jinwon Kim projected that if carbon dioxide levels continue to rise by one percent per year, California will get more rain and less snow, and thus less spring and summer snowmelt when cities and farms need the water most. They also projected warmer winters and hotter summers.
Projections are one thing, reality is another. "We don't really know if it will get wetter or dryer in terms of precipitation," says hydrologist Mike Dettinger of the U.S. Geological Survey in San Diego. "But we do know that it will be warmer, and that drought periods or wet periods may become more persistent, including the possibility of forever droughts that simply don't let up because the climate has changed irreversibly."
But more than droughts or deluge, it's changes in the timing of water highs and lows that may have the biggest impact on California's complicated and carefully negotiated efforts to micromanage flows for the benefit of cities, farms and endangered fish. Right now snowpack sits up in the mountains through the period when most of California's precipitation falls before melting in the spring and summer, when we can catch it all in our reservoirs without worrying about leaving capacity for storms. Climate change will push snowmelt earlier in the year.
"So right now, April 1 is a magical day for water managers," says Dettinger. "Before then, water is the cause of floods and property damage and levee breaks. After April 1, it's hoarded and treated like a resource. If this system gets out of whack with climate change, I personally think we may have to redefine when water is a hazard versus a resource. We may need some major rethinking about how much risk is acceptable."
Changes in when flows come down from mountains to rivers and the Bay will also affect years of efforts, and future projects, to shift flows around to where and when they're needed most. "We now know the importance of high spring flows for salmon and ecosystem restoration," says hydrologist Phil Williams, who worked on EPA climate change studies in the 1980s. "Increasing competition for those diminishing spring flows will make it harder and more important to keep the x2 standard in place." ("X2" is scientific shorthand for a water quality standard established by the 1994 Bay-Delta Accord that requires the 2 parts per thousand isohaline of salt to water to remain with a certain range of positions in the Estuary. That range of positions, which supports optimal food production in the aquatic ecosystem, is determined by the amount of freshwater allowed to flow downstream.) Maintaining the x2 standard, and undertaking the massive estuarine restoration program planned by CALFED, may also be critical to moderating the effects of climate change. A healthier ecosystem adapts better than a weakened one, says Gleick.
So what should water managers be doing now? Williams would like to see more integration of Army Corps flood management efforts in the Central Valley with CALFED efforts to restore floodplains. Better integration of ground and surface water management may also be a must, as droughts or wet periods stress both. Moving people out of flood plains, and curbing sprawl to increase transportation efficiency and reduce fossil fuel consumption and resulting greenhouse gas emissions, are some of the tougher measures that must be taken. Gleick would like to see CALFED factor climate change scenarios into its estimates of future supply and demand for California water, and develop new management rules that increase flexibility in the state's water system.
The international Intergovernmental Panel supports such national and local strategies. "Water demand management and institutional adaptation are the primary components for increasing system flexibility to meet the uncertainties of climate change," it said in a report.
According to Dettinger, studies that document how the demand side of the equation might change in a climate-changed world are much fewer, and more conflicting, than studies of the supply side. "We don't know if plants, or even people, will need more or less water, and any changes may be totally dwarfed by population expansion. On the demand side, we're pretty much flying blind."
Certainly President Bush and American political leaders seem to be flying blind in the face of international pressure to curb the carbon dioxide emissions the promote global warming. This March, Bush went back on a campaign promise to crack down on power plant smokestacks, citing California's energy crisis. And Congress is yet to ratify, and thus commit to implementing, the 1997 global warming reduction treaty known as the Kyoto Protocol.
"The bad news is that our energy crisis is being used to justify a new push for oil drilling in the Arctic wildlife refuge, to develop more fossil fuels nationwide, even to revive a known environmental and economic loser like the Auburn Dam project," says Barry Nelson of the Natural Resources Defense Council. "The good news is that there's broad consensus in California that the cheapest, fastest, cleanest way to solve our energy problems is to promote sustainable energy. There's a stack of bills in the legislature right now saying that energy efficiency is the way to go, and that it's not only the environmental response to this crisis, but the smart response."
California's energy crisis certainly came home to the average person on the street in a way that global warming, however related, never has. "Climate change has become a deeply abstract issue that doesn't touch people's lives," says McKibben.
"To the average citizen, the nation's dams, aqueducts, reservoirs, treatment plants and pipes are invisible. Yet they help insulate us from wet and dry years, and permit us to almost forget about our complete dependence on climate," says Gleick. "We can no longer ignore this dependence. Adaptation is inevitable, and it will come at a very high economic and human cost." Contact: Peter Gleick (510)251-1600; Mike Dettinger (858)822-1507; Phil Williams (415)945-0600; or Norman Miller www.ipcc.ch or www.pacinst.org/naw.htm
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