n California, Climate Change Will Transform the Land, Lifestyles
Dec 28, 2007
Noaki Schwartz - Associated Press
California has always been a place defined by its landscape, from the mountains that enchanted John Muir to the wine country and beaches that shape its culture around the world.
Yet as the state begins to grapple with the effects of a warming climate, scientists are trying to forecast how the nation's most geographically diverse state might change in the decades to come. What they envision is a landscape that could look quite different by the end of the century, if not sooner.
Many of the possible scenarios are gloomy.
Where celebrities, surfers and wannabes once mingled on the sands of Malibu's world-famous beaches, there may be only sea walls defending fading mansions from the ever-encroaching Pacific.
Abandoned ski lifts from Lake Tahoe to the fire-ravaged mountains of Southern California dangle above lonely trails that are now more suitable for mountain biking during much of the winter. The Joshua trees that once extended their tangled arms into the desert sky by the thousands have all but disappeared.
And in Northern California, tourists must drive farther north or to the cool edge of the Pacific to find what is left of the region's signature wine country.
As the global climate warms, California's one-of-kind geography and the lifestyle it has made famous will not escape the consequences.
From the misty redwood forests of the North Coast to the snow-fed waterfalls of the Sierra Nevada, from Southern California's sunbather-jammed beaches to the temperamental wildflowers of the inland deserts, scientists say the changes could be profound.
"We need to be attentive to the fact that changes are going to occur, whether it's sea level rising or increased temperatures, droughts and potentially increased fires," said Lisa Sloan, a scientist who directs the Climate Change and Impacts Laboratory at the University of California, Santa Cruz. "These things are going to be happening."
Concern about the future already is being voiced on California airwaves.
In a marketing blitz to promote increased energy efficiency, the state government has produced a series of haunting television and radio commercials featuring parents and grandparents explaining what kind of state the next generation might inherit because of global warming.
One foretells of endless drought and barren farms. In another, a montage of voices warns, "To my children ... I leave floods and homes under water, and a landscape that isn't the same."
Among the earliest and most noticeable casualties is expected to be California's ski season.
The snow is likely to continue but is expected to fall for a shorter period of time and melt more quickly. That could shorten the ski season by a month even in wetter areas and perhaps end it in others.
In Southern California, where skiing in a region parched by sun and cursed with the hot, dry Santa Ana winds might seem an oxymoron to outsiders, the region is ringed by mountain ranges that cradle several winter resorts. Three peaks within an easy drive of downtown Los Angeles exceed 10,000 feet.
The ski season here has begun to shrivel, whether from short-term drought or long-term changes. Over the last few years, as winter rainfall and snowfall have declined markedly, the resorts have suffered.
"There's always plenty of snow, but you may just have to go out of state for it," said Rinda Wohlwend, 62, who belongs to two ski clubs in Southern California. "I'm a very avid tennis player, so I'd probably play more tennis."
Throughout California, residents will have to adapt in similar ways to warmer temperatures.
Because California is a coastal state with myriad microclimates, predicting exactly what will happen across a land mass a third larger than that of Italy by the end of the century is a challenge.
But through a series of interviews with scientists who are studying the phenomenon, a general description of the state's future emerges.
By the end of the century, temperatures are predicted to increase from 3 degrees to as much as 10 degrees Fahrenheit statewide. That could translate into even less rainfall across the southern half of the state, which already is under pressure from the increased frequency of wildfires and relentless population growth.
The deserts east of Los Angeles are home to small mammals, lizards and colonies of wildflowers that are accustomed to periodic three-year dry spells. But their populations may not be able to withstand the 10-year drought cycles that could become commonplace as the planet warms.
A near four-year drought already has snuffed out certain local habitats for the fringe-toed lizard, a sand-skimming reptile that once was common in the Palm Springs area. Nearby, scientists are considering relocating Joshua Tree seedlings to areas where the trees, a hallmark of the high desert and namesake of a national park, might survive climate change.
They could be wiped out of California depending on how quickly the change happens," said Cameron Barrows, who studies the effects of climate change for the Center for Conservation Biology in Riverside.
Farther north, where wet, cold winters are crucial for the entire state, warmer temperatures will lead to more rain than snow in the Sierra Nevada and faster melting in the spring.
Because 35 percent of the state's water supply is stored annually in the Sierra snowpack, changes to that hydrologic system will lead to far-reaching consequences for California and its ever-growing population. The forecast for 2050 is nearly 60 million people, roughly the current population of France.
Less snowfall means reservoirs and the rivers that fill them could be depleted early in the year. In Yosemite National Park last summer, waterfalls that are a signature for one of the nation's most beloved natural wonders were running at a trickle by midsummer.
Other transformations already are apparent, stretching from the Sierra high country to the great valleys that have made California the nation's top agricultural state.
The changes are not mere speculation. The snowline, as it is in many other alpine regions around the world, is receding in ways that are obvious.
Nate Stephenson, a U.S. Geological Survey ecologist who is studying the effects of climate change in the Sierra Nevada, compared a 2003 photograph of a glacial basin to ones taken of the same area in 1908.
In the nearly century-old pictures, ice can be seen mushrooming over the top of a moraine, the mound of ground-up rock at the bottom of glaciers - "like a muffin bulging over a muffin pan." In the recent photo, the glacier is gone. What remained is a barren bowl, he said.
One creature that thrives at high elevations already is being chased to the brink of extinction by warmer temperatures.
The pika, or rock-rabbit, is adapted to colder temperatures at elevations above the tree line and struggles with temperatures above 70 degrees. The 6-inch-long rodent, which clips grass to create tiny piles of hay to live in during winter, can overheat and die within an hour at higher temperatures.
The population has been dwindling and drifting to ever higher elevations, but biologists fear it eventually will run out of mountain.
"Basically it means that this, like the polar bear, is another animal where the threat is overwhelmingly, primarily global warming," said Brian Nowicki, a biologist with the Center for Biological Diversity in Tucson, Ariz. "It's just going to be the heat that takes it out."
Throughout the 400-mile-long Sierra, trees are under stress, leading scientists to speculate that the mix of flora could change significantly as the century grows hotter. The death rate of fir and pine trees has accelerated over the past two decades.
In the central and southern Sierra, the giant sequoias that are among the most massive living things on earth might be imperiled.
"I suspect as things get warmer, we'll start seeing sequoias just die on their feet where their foliage turns brown," said Stephenson, the Geological Survey scientist. "Even if they don't die of drought stress, just think of the wildfires. If you dry out that vegetation, they're going to be so much more flammable."
Hotter, drier temperatures also would threaten the state's $30 billion agricultural industry.
Higher sustained temperatures could damage the quality of wine grapes in all but the coolest growing regions, such as Mendocino and Monterey counties, according to a study by the Union of Concerned Scientists in Berkeley.
"In the full continental U.S. it's an 81 percent reduction in suitable growing area (for grapes)," said Noah Diffenbaugh, a Purdue University scientist who is studying the effects of climate change on wine production. "It would be on a similar scale in California."
Because the Sierra snowpack accounts for so much of California's water supply, the changes could lead to expensive water disputes between cities and farmers. Without consistent water from rivers draining the snowmelt, farmers in the Central and Salinas valleys could lose as much as a quarter of their water supply.
Some farmers could demand even more water while others will be forced to change the type of crops they grow. Smaller fruit that would ripen faster could be one consequence of an earlier growing season.
Any such changes would have national implications, since California's fertile valleys provide half the country's fresh fruits, nuts and vegetables, according to the Union of Concerned Scientists' study.
"Obviously, it's going to mean that choices are going to be made about who's going to get the water," said Nowicki, of the Center for Biological Diversity.
In one of the ironic twists that global warming could bring, the northern part of the San Joaquin Valley actually could see more water - just the wrong kind.
Rising sea levels will imperil the vast Sacramento-San Joaquin Delta, forcing sea water from San Francisco Bay farther inland and impeding the flow of the northern rivers. The result could be a huge inland lagoon in what is now a mix of farms, rivers and suburbs.
What will happen along California's famed coastline will affect the rest of the state, yet is among the biggest unknowns.
One scenario suggests that chunks of the Greenland ice sheets, which have been melting, could simply tumble into the ocean, causing sea level to rise more than 20 feet.
Will the rising seas swamp the ports of Long Beach and Los Angeles, the nation's busiest port complex, turning them into a series of saltwater lakes? Will funky Ocean Beach, an island of liberalism in conservative San Diego County, become, literally, its own island?
Among the more sobering projections is what is in store for the marine life that hugs the state's shoreline.
The upwelling season, a time when nutrient-rich waters are brought from the ocean's depths to the surface, creates a food chain that sustains one of the world's richest marine environments along the California coast.
That period, which spans from late spring until early fall, is expected to become weaker earlier in the season and more intense later. Upwelling in Southern California will become weaker overall.
As a result, sea lions, blue whales and other marine mammals that follow these systems up and down the coast are expected to decline.
"When you take away upwelling, there's less food. And when there's less food available, there'll be fewer of everything," said Dan Costa, an expert in marine mammals and sea birds at the University of California, Santa Cruz. "The number of species will decline across the board."
Increased temperatures could turn Southern California's undulating kelp forest into a scraggly collection of brown seaweed by the end of the century, experts said. Already stressed marine animals that depend on kelp, such as California's struggling population of 3,000 otters, could have an even tougher time.
"A warming of the ocean is going to be detrimental for otters," said Jim Estes, an otter expert and research scientist for the U.S. Geological Survey.
Changing seas will present trouble for much of the state's land-dwelling population, too.
A sea level rise of three to six feet will be enough to inundate the airports in San Francisco and Oakland.
"If you raise sea level by a foot, you push a cliff back 100 feet," said Jeff Severinghaus, professor of geosciences at the Scripps Institution of Oceanography in San Diego. "There will be a lot of houses that will fall into the ocean."
Many of the state's beaches are expected to shrink as sea levels rise and winter storms carry away sand.
The popular beaches of Santa Monica, Venice and Newport Beach are maintained entirely by expensive sand-nourishment programs that may become impossible to continue.
At the same time, an expected increase warm winter storms could benefit one iconic California activity - surfing. Even so, surfers aren't exactly anxious for the coming changes, said Chad Nelson, environmental director with the Surfrider Foundation.
"Of course if the water's too polluted to surf because it's raining and the houses are falling into the water because the sea level is rising, that could detract from the experience," he said.
Saturday, December 29, 2007
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