Climate change drives wildfires

Someone recently told me that the heat wave broke when the daytime high temperature earlier this week dropped below 100 degrees. I suppose that one interpretation of our recent weather pattern is: 100 is hot; 99 is not.

Part of the problem with distinguishing local heat waves from other weather patterns is that we have a heat wave every summer in the Central Valley. The troubling thing is that the heat waves are getting longer and more intense. And, this is part of an overall pattern that is affecting the entire world.

Climate change deniers can probably find exceptions to the following adages concerning California:

• Wildfires are the new normal.

• Drought is the new normal.

• Temperature extremes are the new normal.

• Warmer oceans are the new normal.

However, if one were to find a concrete exception to any or all of the statements, it would be just that: An exception. We know for a fact that we broke the old 21-day record of 100-degee daytime high temperatures. Then, we broke it again the next day. And, the next. And, the next, etc. Warm water

On Aug. 4, in San Diego County, we broke the record for the warmest ocean temperature with 78.6 degrees, the highest ocean water temperature ever recorded since measurements began more than a hundred years ago. At the time, oceanographer Clarissa Anderson told NPR, “Human-driven climate change has already raised global sea temperatures by nearly 2° F, so we can expect the frequency of record-breaking incidents to increase.” Sure enough, two days later scientists at Scripps Institute in La Jolla measured the water’s temperature at 78.8 degrees. That’s the new, new record.

Writing for Forbes magazine, Priya Shukla of UC Davis observed, “Warm ocean temperatures in San Diego are consistent with record-breaking ocean temperatures in Australia in 2015 and 2016, and across the world’s oceans in 2017.” She added that these phenomena “are also consistent with a spate of warming events … that have enabled multiple wildfires in the past few months.”

Rong-Gong Lin II and Javier Panzar, writing for the Los Angeles Times, point out, “Palm Springs had its warmest July on record, with an average of 97.4 degrees. Death Valley experienced its hottest month on record, with the average temperature hitting 108.1.” Death Valley’s previous record high for the month of July was last year. At that time, it broke the previous 100-year-old record when average temperature hit 107.4 degrees.

And, there has been little relief when the sun goes down. Across the state, we experienced the highest minimum temperature of any month. Last month, the statewide average nighttime low temperature was 64.9 degrees. Lin and Panzar say, “California has been getting hotter for some time, but July was in a league of its own.”

Meteorologist Samantha Connolly told the Los Angeles Times, “Of particular concern is how overnight temperatures continue to climb. The years with the top six warmest summertime minimum temperatures in California — defined as June through August — in descending order, are 2017, 2015, 2014, 2006, 2016, and 2013.” Big fires

Regional climatologist Nina Oakley pointed out that the day when the temperature hit 113 in Redding (July 26), the Carr Fire went out of control, killing people. She said, “It was one day among months of above-average temperatures that had dried out the brush to such a degree that it helped fuel the blaze’s ferocious spread.” She commented that the lack of lower temperatures overnight made the fires harder to fight. “You have greenhouse gases acting like a blanket and not letting things cool down …”

The intense heat has fueled wildfires from San Diego County to Redding, where the fire that is still raging has already been determined to be the state’s largest in history. So far, more than 1,000 homes have been destroyed and nine lives have been lost. On Wednesday, 16 other large fires were burning statewide. Appearing on NBC-TV, Glenn MacDonald, Professor of Geography and Environmental Science at UCLA, stated that 16 of the 20 largest fires ever recorded in California have occurred since 2000.

I think that one of the factors that motivates people to reject the idea that human factors are causing climate change is the notion that we really can’t do anything to undo the damage that we’ve brought about. So, let’s just deny that we’ve caused it. But, that’s an ineffective conclusion. In fact, we know what has damaged our environment. And, we know what we need to do to slow the process and — eventually — to reverse it. Past actions

Consider the ozone layer that surrounds the earth and filters the ultraviolet rays from the sun. A decrease in ozone high above the earth would lead to increases in skin cancer and possibly changes to our DNA. So, while ozone at ground level is bad for us, ozone in the upper atmosphere is an absolute necessity.

In 1974, Sherwood Rowland and Mario Molina at UC Irvine concluded, based on computer modeling, that chlorofluorocarbons (CFCs) were endangering the ozone layer. Their work went unheeded. CFCs were used in aerosol spray cans, refrigeration, and vehicle air conditioning. They were also used in the manufacture of foam and cleaning agents. During the 1980s, the CFCs in our atmosphere increased by 40 percent.

The first warning was detected in 1985 when scientists discovered a hole in the ozone layer above the South Pole. Ten years later, the hole had grown to the size of Europe, measuring 3.9 million square miles. By the turn of the century, it was 8 million square miles.

In 1992, leaders from half of the world’s countries met in Copenhagen and agreed to phase out the use of CFCs. At the time, they knew that there would be no “overnight miracle.” The problem was that all the CFCs added to the atmosphere were still there, and the substitute for the gas was simply less destructive. The world had to have patience.

In 2015, a NASA study showed that the hole in the ozone had stopped growing and was showing signs of shrinkage. The authors concluded, “With this new information, we can look into the future and say with confidence that the ozone hole will be consistently smaller … By 2100, the hole could be completely gone.”

Once we recognize a problem for what it is and ascertain the solution, we can effect positive change.

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Jim Glynn may be contacted at j_glynn@att.net.