Cal Fire says this wildfire season is one of the worst on record.
To date, 4,743 wildfires have consumed 146,279 acres. For comparison, last year at this time there were 3,285 fires that burned 89,358 acres. Earlier this month, one Lake County wildfire burned 25,000 acres, an area three times bigger than the city of San Luis Obispo, in less than six hours!
Unfortunately, wildfires are likely to get worse in the future.
As any firefighter will tell you, three ingredients are needed to have a fire — oxygen, heat, and fuel — “the fire triangle.” A heat source such as a spark from a trailer chain hitting the highway can cause a fire to ignite, but the heat also preheats the fuel in the fire’s path, allowing it to spread.
This year’s record heat has dramatically lowered the moisture content of vegetation, allowing it to burn easier and hotter. Along with warm temperatures, stronger than normal winds not only help to dry vegetation through evaporation but also provide plenty of oxygen for combustion.
Overall, warmer temperatures, cumulative winds and drought have fed into a dreadful feedback loop. Average yearly temperatures are forecast to rise by six degrees by the end of this century. Locally, temperature records keep falling like bowling pins. So far, 2015 has seen 13 high temperature records broken at the Paso Robles Municipal Airport and nine at the San Luis Obispo County Regional Airport.
Even more telling, there was only one low temperature record reported, which occurred in San Luis Obispo on New Year's Day.
At the current pace, 2015 could produce the most daily high temperature records ever seen in San Luis Obispo County in one year. In fact, the last four years has seen more maximum temperatures broken than any other four-year period in 122 years of meteorological data keeping at Cal Poly.
Not only will the atmosphere get warmer, but droughts may become longer. Average temperatures in the Arctic have increased at about two to three times faster relative to the midlatitudes. This is referred to as Arctic Amplification. Many climatologists and scientists suspect this condition could be behind the big and persistent ridge of high pressure over California that has produced unprecedented dry conditions over the last four years.
However, a warmer atmosphere can hold a greater amount of water vapor with the potential of more intense rainfall events. Whether or not a strong El Niño develops, during the peak rainfall months of this December, January and February, Pacific storms will more than likely yield rain and with it the threat of erosion in the burn areas.
According to Cal Fire public information officer Bennet Milloy, “Erosion can take place up to three and four years after the fire. Nonetheless, even if we receive heavy rain this year, the ongoing drought has killed up to 90 percent of the timber and vegetation in certain locations, like Cambria. This will make firefighting more difficult for years to come.”
According to Cal Fire, a 300 percent increase in wildfire risk in non-urban areas of California is predicted by 2050 due to climate change. “The fire season has involved into a year-round event,” said County/Cal Fire Chief Robert Lewin. “Technically, we’re still in the 2013 fire season. We haven’t been able go to normal winter staffing since then.”
As wildfires rage across California, PG&E is joining forces with Cal Fire to ask for the public's help to reduce the risk of additional wildfires by safely removing or pruning dead or dying trees from their property. For more information, please visit www.pgecurrents.com