Thursday 12 March 2009

Global warming to carry big costs for California

The Associated Press
Published: March 11, 2009

SACRAMENTO, California: From agricultural losses to devastation wrought by wildfires, California's economy is expected to see significant costs resulting from global warming in the decades ahead, according to a series of studies released Wednesday.
The reports presented to Gov. Arnold Schwarzenegger's climate advisers illustrate the potential effects of climate change on America's most populous state, which is also the eighth-largest economy in the world.
Global warming could translate into annual costs and revenue losses throughout California's economy of between $2.5 billion and $15 billion by 2050. Property damage caused by sea level rise and more devastating wildfires could push the costs far higher.
The projected financial toll comes from a compilation of 40 studies commissioned by the governor's climate advisers. The reports are intended to provide a comprehensive snapshot of global warming's potential costs to property owners, businesses and state government.
"The numbers indicate that we have a lot at stake," said Michael Hanemann, a professor in the Department of Agricultural and Resource Economics at the University of California, Berkeley. "Californians need to pay serious attention to control our greenhouse gas emissions, and they need to start thinking about adaptation."

The studies were written by scientists from various disciplines based at California universities and research institutions. They include a range of costs from agriculture, wildfires, water supply, flooding and electricity demand. The studies are expected to be released in a comprehensive report by the end of the month.
If nothing is done globally to reduce emissions, hotter temperatures will lead to rising sea levels that will flood property in San Francisco, lead to lower crop yields and water shortages, produce more intense wildfires and cause more demand for electricity to cool homes.
Dealing with those scenarios could cost California between $2.5 billion to $15 billion a year, according to the presentation delivered Wednesday to Schwarzenegger's 16-member Climate Action Team. But even those numbers are conservative, said Hanemann, who reviewed the studies.
For example, lower crop yields are likely to occur during extreme weather when temperatures soar higher than normal. However, the climate models that calculated the $3 billion in potential crop losses used average monthly weather data that is lower than temperatures on the hottest days that cause crop damages.
"The monthly data understates the extreme temperature events — and that understates the damage," Hanemann said.
The annual costs also could be greater at the end of the century, ranging from $14 billion a year to $45 billion in 2085. Total cumulative property losses from wildfires and floods at that time could range from $105 billion to $334 billion.
California's total annual economic output is estimated at $1.8 trillion.
The reports come as California regulators are implementing a 2006 state law that requires greenhouse gas emissions to be cut to 1990 levels by 2020.
Even as that regulatory process plays, emissions have continued to rise in the U.S. Heat-trapping emissions grew nationally by 1.4 percent from 2006 to 2007, according to a draft greenhouse gas inventory released earlier this month by the Environmental Protection Agency.
If emissions are reduced on a global scale, economists say the financial impact on California would be lessened but not eliminated. For example, annual revenue losses for California farmers would be cut in half to about $1.5 billion by 2050, while overall electricity costs actually might be less than today.
Linda Adams, secretary of the California Environmental Protection Agency, said the research shows why the state needs to cut carbon emissions aggressively over the next 40 years.
"It will cost significantly less to combat climate change than it will to maintain a business-as-usual approach," Adams said.