Could a hurricane hit California?
Rhett Butler, mongabay.com
August 20, 2007


San Diego has been hit by hurricanes in the past and could be affected by such storms in the future according to data from the National Oceanic and Atmospheric Administration (NOAA). While a hurricane in San Diego would likely produce significantly less damage than Hurricane Katrina in New Orleans, it could still exact a high cost to Southern California especially if the region was caught off guard.

Hurricane Katrina was particularly devastating to New Orleans because the city lies below sea level and is surrounded by three large bodies of water -- Mississippi River to the south, Lake Pontchartrain to the north, and the Gulf of Mexico to the east. In New Orleans, most destruction was associated with flooding. Flooding would likely be less of a concern in San Diego which sits at a higher elevation and would more easily be evacuated than the Louisiana city. However, San Diego and other Southern California communities could expect more wind damage and destruction caused by mudslides. In 2005, mudslides and rockfalls resulting from heavy rains killed ten people and destroyed 15 homes in La Conchita, California.

Hurricane Risk in California


This image combines data from various NASA satellites and shows sea surface temperatures (80F or higher) warm (orange areas) enough to power tropical cyclones. The darker the orange color, the warmer the water. Courtesy of NASA
While most hurricanes in the United States impact the East Coast and Gulf region, the West Coast is also vulnerable. According to research presented in 2005 at the annual meeting of the American Meteorological Society in San Diego, California, a tropical cyclone brought hurricane-force winds to San Diego in 1858.

"On October 2, 1858, estimated sustained hurricane force winds produced by a tropical cyclone located a short distance offshore were felt in San Diego," said Christopher Landsea, the co-author of a paper on the 1858 hurricane and a hurricane researcher at NOAA's Hurricane Research Division at the Atlantic Oceanographic and Meteorological Laboratory in Miami, Fla. "Extensive damage was done in the city and was described as the severest gale ever felt to that date, nor has it been matched or exceeded in severity since."

Coral evidence suggests the ocean was particularly warm that year and, according to a press release from NOAA, "warmer waters and a conducive atmosphere allowed the hurricane to sustain Saffir-Simpson Hurricane Scale Category 1 intensity (wind speed of 72-95 mph) as far north as southern California. Available evidence suggests that the hurricane tracked just offshore from San Diego, without the eye coming inland, but close enough to produce damaging winds along the entire coast from San Diego to Long Beach."

Should such a storm return it would cost the region hundreds of millions to billions of dollars in damage according to Christopher Landsea and Michael Chenoweth, authors of the study.

"What this also tells us is that a hurricane has directly affected southern California in recorded history and we should remember that if the conditions are right, the area could get hit again," Landsea said. "Mike and I hope that emergency managers, residents of the area, business owners, the insurance industry, and decision-makers be made aware of this possibility, as most in southern California may think they are completely safe from hurricanes because they are on the Pacific coast instead of the Atlantic."

Impact of Climate Change on Hurricanes

While there is considerable date over whether observed climate change is behind the recent increase in hurricane activity in the Atlantic basin, several studies suggest that warmer oceans could produce stronger storms in the future. Kerry Emanuel, the author of a study published in Nature, warns that since hurricanes depend on warm water to form and build, global climate change might increase the effective range of hurricanes in coming years. It is conceivable that a warmer Pacific could someday enable a hurricane to strike cities farther north, even Los Angeles.

Hurricanes already nearby in Mexico

Hurricanes do batter Baja California (the northernmost state of Mexico, located just south of San Diego) from time to time, usually coinciding with El Niño years. In September 1997, an El Niño year, Hurricane Linda became the strongest storm recorded in the eastern Pacific with winds estimated at 180 mph For a time there was concern that Linda would come ashore in California as a tropical storm, but the storm turned away and the state only experienced high surf and thunderstorms. More recently, in 2006, the Pacific coast of Mexico was battered by Hurricane John and Hurricane Kristy.

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This article is an updated version of a mongabay.com article that appeared September 8, 2005. This article uses quotes an information presented in a National Oceanic and Atmospheric Administration press release issued Jan. 11, 2005.





CITATION:
Rhett Butler, mongabay.com (August 20, 2007).

Could a hurricane hit California?.

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