A daily compilation of significant news articles and comment
July 21, 2008
3. Watersheds –
Rejuvenated Bolsa Chica wetlands flourishing
The $147-million project that reconnected the
Warming West is ground zero for wildfires
San Francisco Chronicle
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Rejuvenated Bolsa Chica wetlands flourishing
The $147-million project that reconnected the
By Susannah Rosenblatt,
Two years ago, the saltwater oasis off
Now, waters lap sandy shoals next to
With every spawning grunion and nesting sparrow, the Bolsa Chica wetlands in
By blasting through part of a parking lot and a century-old barrier created by duck hunters, engineers reconnected the 367-acre tidal basin with the ocean. Since then, a steady parade of sea creatures have found their way to a revived saltwater home, bringing multitudes of hungry shorebirds with them.
The $147-million rebirth has triggered population explosions, with scallops multiplying, followed by topsmelt, halibut, rays and small sharks.
Newly built nesting sites offer refuge for a number of endangered birds, such as the
"The change is dramatic and continues to improve as time goes on," said Kelly O'Reilly, associate marine fisheries biologist with the state Department of Fish and Game. "I've been watching the place kind of come to life over the last year and a half."
The transformation of the swatch of undeveloped beachfront property follows nearly 40 years of acrimony and lawsuits between developers, nearby residents and the state and federal governments. Pitting environmental hopes against real estate ambitions, the protracted legal scrum ultimately scuttled plans for a marina and large waterfront neighborhood.
With rows of homes and active oil derricks at its edge, Bolsa Chica serves as a vital island for wetlands dwellers -- and an unexpectedly peaceful spot for visitors.
Experts estimate that about 95% of
"To see these few remnant wetlands that we still have left is just great," said Robert Hoffman, an assistant regional administrator for habitat conservation with the National Marine Fisheries Service. "It's great from an ecological perspective. It's great from an open-space perspective."
The project, which rejuvenated more than three-fourths of Bolsa Chica's roughly 1,300 acres, is the largest restoration of its kind west of the Mississippi, said Jim Trout, the former Bolsa Chica project coordinator for the California State Lands Commission.
As more animals are drawn to this recovering habitat -- including a burgeoning tern population -- they're forced to live on top of one another, occasionally crushing nests of eggs in their struggle for space.
Biology graduate students shivering in wetsuits wade through the tidal basin with giant nets, capturing and measuring marine life. This fall, managers of the site hope to open gates that will let more ocean water flow into shallower tidal areas; spindly stalks of cordgrass are expected to multiply, providing shelter for the endangered light-footed clapper rail. And 300,000 cubic yards of sand that has washed in from the adjacent beach, providing surprisingly fertile spawning grounds for burrowing grunion, will be dredged in September to keep the tidal channel clear.
In the meantime, Aera Energy continues to operate an oil field next to the basin, as elegant terns plummet headfirst into the water to snatch pipefish. Whenever the company pumps that 248-acre section dry of oil, that property too will be allowed to revert to its natural state.
As the ecosystem changes over the next five years, biologists are anticipating that as many as 60 fish species will settle in Bolsa Chica. (Of 135 species recently observed in the restored area, 27 are fish.) Divers transplanted eel grass from
Eight state and federal agencies are overseeing the health of the fledgling wetlands. Monitors regularly observe tidal patterns, fish populations, bird communities and vegetation growth, as occasional adjustments are made to water levels.
The fragile estuary was once fated to give way to about 6,000 homes. Community groups' lawsuits and negotiations with coastal regulators whittled the proposed development to fewer than 500 homes, said Gerald Chapman, president of the nonprofit Bolsa Chica Land Trust. Funds for the restoration effort, which came mostly from the ports of
But environmental activists continue to fight to preserve nearby lands and Native American remains and artifacts found there.
Although the new tidal area remains closed to the public, Huntington Beach Mayor Debbie Cook, a longtime Bolsa Chica advocate, envisions connecting trails from the city's
The creation of a flourishing salt marsh where an oil field once stood is "a heck of a lot better than a marina and high-rise hotels and another Marina del Rey," Chapman said. "People are just wildly surprised that all of these things are here right in their backyard."#
http://www.latimes.com/news/science/environment/la-me-bolsa20-2008jul20,0,2343337.story?track=rss
Warming West is ground zero for wildfires
San Francisco Chronicle – 7/21/08
By Jane Kay, staff writer
The American West has been warming dramatically during the past 60 years at a rate surpassed only by
Some of the state's top scientists say the changing water picture is caused by humans producing greenhouse gases, and the U.N. Intergovernmental Panel on Climate Change predicts more intense and longer droughts with warmer spring and summer temperatures in the West.
That, scientists say, leads to increases in the length of the fire seasons, number of fires, time needed to put out the fire and size of the burned area.
"The snow melts sooner, the dry season gets longer and rivers crest earlier. That gives more of a chance for drying out and therefore a likelihood of more fires," said Tim Barnett, a climatologist at the Scripps Institution of Oceanography at UC San Diego who led research on the effects of greenhouse gases on the changing hydrology in the western
"If you look at where we will be in 20 or 30 years, we'll have serious problems," he said.
Scientists are quick to caution against blaming one fire or heat wave on global warming. But, Barnett said, "At the minimum, you're getting a glimpse of your future. Do you like it? I think not."
Complex causes
Research by teams of scientists at Scripps, Lawrence Livermore National Laboratory, the U.S. Geological Survey and other institutions have probed associations between land-use patterns and climate change because of increases in fires during the past 25 years.
The picture is complex, particularly in
With warmer and earlier springs, moisture has been uneven, and winter precipitation in some parts tends to come as rain, not snow. At the same time, logging and mining have changed the character of forests, and the practice of preventing low-burning fires in past decades may have made the forests more susceptible to wildfires, experts say.
But taking all of the factors into consideration, including weather patterns shown in tree rings over past centuries, they conclude that the intensity of fires is linked most closely to the rising temperatures, less snowpack, earlier snowmelt and a longer, drier fire season.
The peak time of melting snow is already about 10 to 15 days earlier in different parts of the West. Scientists have projected a speed-up of 25 to 35 days earlier by the end of this century. A study just released by
Temperatures rising
In the western
Turning up the heat
The West has had more frequent and severe heat waves, with the number of extremely hot days increasing by up to four days per decade since 1950, according to research supported by the Rocky Mountain Climate Organization, a coalition of 17 local governments, businesses, nonprofits and
The West has warmed more than east of the
Drought is now more common in the West, while east of the Rockies it is noticeably wetter in general, said Kevin Trenberth, head of the climate analysis section at the
"All of this indeed promotes wildfire risk, and the 'dry lightning' is disastrous, especially in areas where trees are damaged such as by bark beetle," said Trenberth, a lead author of the center's 2007 scientific assessment of climate change.
This year followed the trend.
"We had very dry conditions in April, May and a bit of June," said Scott Stephens, associate professor of fire science in UC Berkeley's department of environmental science, policy and management. "This year, we had almost zero rain. When the dry lighting strikes came through, we had 1,000 fires in one weekend, June 20, one of the highest we've ever experienced," something not seen in at least 50 years, he said.
So far, more than 900,000 acres have burned, destroying about 100 houses and threatening thousands more. People were evacuated in Big Sur, the Sierra foothills and
"We're going to have more surprises like this," Stephens said.
Duration of burns increases
Since 1980,
In the past three decades, the wildfire season in the western United States has increased by 78 days, according to work led by Anthony Westerling, formerly at Scripps, now at UC Merced. Roughly half that increase was due to earlier ignitions, and half to later control. Burn duration of fires greater than 1,000 acres has increased from 7.5 to 37.1 days in response to a spring-summer warming.
People on the fire lines see that the wildfire intensity and size have changed and question whether global warming is to blame, Stephens said. "They know that the temperatures are increasing, and the snow is leaving earlier. One thing is certain: Weather and fire are tied together. They know that better than anybody."
The U.S. Forest Service has a study in progress that examines the severity of forest fires in the
The researchers found that fires had increased in severity beginning in the 1980s and continued until today. By analyzing state and federal data, they also showed that fire frequency, total burned area and average fire size have also increased during the same period.
Rising temperatures play a part, they said. But at the same time, they found that increases in forest density because of 70 years of fire suppression are also to blame.
The study concluded that "in light of recent alarming projections for increased temperatures and fire-season length by the end of the century," it is time to rethink the current policy of suppressing fires and, under the proper circumstances, let more fires burn to reduce problem fuels.
Wildfires and climate by the numbers
Climate scientists predict a continuing trend of rising temperatures in the West. The warmer the spring, the earlier the snowmelt, the drier the summer, the longer the fire season and the higher the frequency of big fires, they say. Multiyear droughts degrade trees' abilities to generate defensive chemicals, increasing their susceptibility to insects. Higher winter temperatures allow a larger fraction of overwintering larvae to survive. Spruce budworm in
-- Since 1980,
-- The forested area that burned in the western
-- In the past three decades, the wildfire season in the western
http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2008/07/21/MNSC11Q7RD.DTL
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