First understand Southern California is naturally dry. Its Mediterranean climate means it rarely rains in the summer and has a limited winter rainy season. Three deserts in the region attest to its dry climate. 

As a result, the vegetation around Los Angeles primarily consists of one-hour fuels that can dry in as little as 60 minutes, including dead grasses, leaves and pine needles, and 10-hour fuels that include dead small branches, 1/4 inch to 1 inch in diameter. Able to retain moisture but briefly, this material is essentially kindling. 

While a rainstorm can make the vegetation temporarily fire resistant, as soon as the rains stop, the drying process begins. Dead grasses and twigs can become highly flammable within 12 to 24 hours. Due to natural climate oscillations like El Nino, in contrast to this dry year, the previous year’s above-average rains increased the amounts of combustible 1-hour and 10-hour fuels 

Los Angeles’s rainy season runs December through February, but the monthly average is only 6 days with rain. Thus, there are usually about 24 dry days during each winter month when vegetation quickly becomes flammable. The length of the natural summer drought or the timing of the winter’s first rain are immaterial to the fundamental aridity of Southern California. 

While climate alarmists like Michael Mann blame the fires on man-made global warming, December dryness is not unusual. In fact, the January 9^th fires were preceded of a 30-day trend of increasing rainfall, but that obviously was not a factor. 

Furthermore, the winter rainy season coincides with the time of the Santa Ana winds. The winds originate in the cold high deserts and blow down the mountainside to the warmer ocean. As they descend, the winds warm and dry further, typically with a relative humidity below  

10% that rapidly dries out the vegetation. 

When determining the safety of a prescribed burn, the U.S. Department of Agriculture considers there to be a 100% chance of fires spreading when relative humidity is 25% or less. Little wonder that the National Weather Service warned of dangerous conditions when weather systems lined up to amplify the dry winds. The strongest Santa Anas in a decade were predicted.  

The region’s last big fire – the December 2017 Thomas Fire – was ignited when Santa Ana winds caused electrical wires to spark. 

Knowing that natural, lethal fire dangers are always looming for the growing population, the question is whether city and state governments could have been better prepared to minimize ignitions and more efficiently contain a fire’s spread through southern California. When fires reach neighborhoods with densely packed houses, one burning structure can radiate enough heat to ignite adjacent buildings causing entire neighborhoods to burn to the ground. 

Accordingly, ordinances to create a defensible space around homes were enacted in recent decades to keep the height of grass and native brush less than 3 inches within 200 feet of a building. Roofs on new buildings and replacements must be fireproof. But how well such ordinances have been followed is not clear. Nor is it clear if adequate brush management was maintained in adjacent public lands to slow the spread of fire into populated areas. In any case, the flames reached enough homes to cause entire neighborhoods to be destroyed. 

The cause of the wildfire ignitions has yet to be determined, but it is absolutely certain it wasn’t due to lightning strikes. During high winds, downed electrical wires are frequent sources of ignitions and likely suspects. However, somewhat unique to large cities like Los Angeles, fires related to homelessness have increased, rising to 13,909 fires in 2023 and doubling since 2020. Those fires sometimes originated with fires that were set to keep warm. But arsonists caused others, such as one of LA’s conflagrations, the Kenneth Fire. 

In addition to ineffective policies to address homelessness, many believe government spending priorities have exacerbated the fire threat. For example, LA has increased expenditures on services for the homeless to $1.3 billion.  In contrast, budgets for fire prevention were reduced by LA mayor Karen Bass and Governor Newsome by $18 million and $100 million, respectively.  

Finally, water-management policies may have also hurt the ability to contain fires, as several hydrants ran out of water. The Santa Ynez Reservoir in Pacific Palisades was dry and off-line. Could money cut from fire-prevention budgets have been used to install more water storage tanks to offset reduced reservoir supplies? Should governments have increased budgets to build more reservoirs. Could systems using ocean water to stop such devasting fires be investigated?  

Climate alarmists like Michael Mann claim it is the increase of CO₂ causing drier conditions that correlates with bigger fires. But the data do not support his fearmongering. 

An increase in the destruction of property by wildfires better correlates with population growth and the expansion of an electrical grid that is vulnerable to high winds. Increased 1-hour fuels and 10-hour fuels due to land disturbances and poor land management correlate with bigger fires. Increased homeless populations correlates with more ignitions. 

Blaming climate change for these disasters only deflects attention away from actual causes. Fabrications linking rising CO₂ to wildfires should be ignored. Governments must employ solutions that will truly protect people and their property from the unstoppable, natural conditions enabling devastating fires. 

James Steele is a biologist, author and former director of San Francisco State University’s Sierra Nevada Field Campus. He is a proud member of the CO₂ Coalition. 

This commentary was first published at CO2 Coalition website, and can be accessed here.

James Steele is a biologist, author and former director of San Francisco State University’s Sierra Nevada Field Campus. He is a proud member of the CO₂ Coalition.