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Climate Changes Expected To Transform California
LOS ANGELES (AP) - California is defined by its scenery, from the mountains
that enchanted John Muir to the wine country and beaches that define its culture
around
the world.
But as scientists try to forecast how global warming might affect the nation’s
most geographically diverse state, they envision a landscape that could look
quite different by the end of this century, if not sooner.
Where celebrities, surfers and wannabes mingle on Malibu’s world-famous
beaches, there may be only sea walls defending fading mansions from the encroaching
Pacific. In Northern California, tourists could have to drive farther north or
to the cool edge of the Pacific to find what is left of the region’s
signature wine country.
Abandoned ski lifts might dangle above snowless trails more suitable for
mountain biking even during much of the winter. In the deserts, Joshua trees
that once
extended their tangled, shaggy arms into the sky by the thousands may have
all but disappeared.
“
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 scientists who directs the Climate
Change and Impacts Laboratory at the University of California, Santa Cruz. “These
things are going to be happening.”
Among the earliest and most notable casualties is expected to be California’s
ski season.
Snow is expected to fall for a shorter period and melt more quickly. That
could shorten the ski season by a month even in wetter areas and perhaps end
it in
others.
Whether from short-term drought or long-term changes, the ski season already
has begun to shrivel in Southern California, ringed by mountain ranges that
cradle several winter resorts.
“
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.”
Because California has myriad microclimates, covering an area a third larger
than Italy, predicting what will happen 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 by 3 to
10 degrees Fahrenheit statewide. That could translate into even less rainfall
across the southern half of the state, already under pressure from the increased
frequency
of wildfires and relentless population growth.
Small mammals, reptiles and colonies of wildflowers in the deserts east of
Los Angeles are accustomed to periodic three-year dry spells. But they might
not
be able to withstand the 10-year drought cycles that could become commonplace
as the planet warms.
Scientists already are considering relocating Joshua tree seedlings to areas
where the plants, a hallmark of the high desert and namesake of a national
park, might survive the 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 water supply of
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.
Some transformations already are apparent, from the Sierra high country to
the great valleys that have made California the nation’s top agricultural
state.
The snow line is receding, as it is in many other alpine regions around the
world. Throughout the 400-mile-long Sierra, trees are under stress, leading
scientists
to speculate that the mix of flora could change significantly as the climate
warms. 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
biggest 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 Nate Stephenson, a U.S.
Geological Survey ecologist who is studying the effects of climate change in
the Sierra Nevada. “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.”
Changes in the mountain snowpack could lead to expensive water disputes between
cities and farmers. Without consistent water from rivers draining the melting
snow, farmers in the Central and Salinas valleys could lose as much as a quarter
of their water supply.
Any drastic changes to the state’s $30 billion agriculture industry 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 Brian Nowicki, a biologist with the Center
for Biological Diversity in Tucson, AZ.
Among the biggest unknowns is what will happen along California’s coast
as the worlds ice sheets and glaciers melt. One scenario suggests the sea level
could rise by more than 20 feet.
Will the rising sea swamp the ports of Long Beach and Los Angeles, the nation’s
busiest harbor 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 marine life.
The upwelling season, the time when nutrient-rich water is brought from the
ocean’s
depths to the surface, nourishes one of the world’s richest marine environments.
That period, from late spring until early fall, is expected to become weaker
earlier in the season and more intense later. Upwelling along the Southern
California coast 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.
The changing sea will present trouble for much of the state’s land-dwelling
population, too. A sea level rise of 3 to 6 feet would inundate the airports
in San Francisco and Oakland. Many of the state’s beaches would shrink.
“
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.”
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