Editor's note: An earlier version of this story had incorrect information. The story quoted the scientist as saying that if worldwide carbon emissions continue to rise at the present rate, rising temperatures could cause the Sierra Nevada to lose 80 percent of its winter snowpack in just 40 years. The correct numbers are that the Sierra Nevada could lose 80 percent of its winter snowpack by the end of the century (not 40 years), according to Leslie C. Gordon, a spokesperson for USGS in Menlo Park.
By Chris Cooney
Bay City News Service
If worldwide carbon emissions continue at the present rate, rising temperatures could cause the Sierra Nevada to lose 80 percent of its winter snowpack by the end of the century, a U.S. Geological Survey scientist said Thursday in a Menlo Park talk.
The decrease in snowfall is among several grim impacts that climate change could have if current carbon emissions go unabated, said USGS climate change coordinator Tom Suchanek in a talk at the USGS campus in Menlo Park.
He said that some effects of climate change are already impacting life in the Bay Area and across the country, such as year-round high temperatures that are "breaking records right and left."
"Temperatures are climbing all the time and climbing rapidly," he said.
Higher temperatures -- between 3 and 6 degrees higher depending on projection models -- carry a barrage of side effects, including heat waves that are longer-lasting and more intense, increased fire danger, and winter storms that are stronger, more violent and more frequent.
Mr. Suchanek said that "1,000-year storms" are already 10 times more frequent now than they were in the 1920s. "We now have multiple 1,000-year storms per decade," he said.
Climate change is also expected to usher in a significant rise in sea levels, he said. With no change in current carbon emissions, sea levels are projected to rise at least 1.4 meters in Northern California by the year 2100.
Higher sea levels will bring higher wave heights, which will lead to increased beach erosion, cliff failures and coastal flooding, he said. Cities, beach towns and every coastal ecosystem from marshland to redwood forest would be impacted.
There is still hope to curb carbon emissions if countries that burn the most fossil fuels -- China, the U.S., India and Russia -- continue to develop alternative energy sources and work through the United Nations Framework on Climate Change to draft a treaty that would reduce emissions worldwide, he said.
But for the U.S. to join any treaty, it first has to be ratified and approved by both houses of Congress, which in the current political climate does not seem likely at all, Mr. Suchanek said.
■ A video of the talk is expected to be posted online about a day after the lecture in the USGS video archives.