Sign In or Create an Account.

By continuing, you agree to the Terms of Service and acknowledge our Privacy Policy

Guides

Does Climate Change Make the Santa Ana Winds Worse?

The legendary winter gusts have long freaked out Angelenos.

The Santa Ana winds.
Heatmap Illustration/Getty Images, NASA Earth Observatory

“It is the season of suicide and divorce and prickly dread, wherever the wind blows,” the great Los Angeles chronicler Joan Didion once wrote of the Santa Ana winds. It also happens to be the season of wildfires. The winds “bedeviled” efforts to fight the deadly Woolsey fire in 2018 and created “dangerous conditions” when they whipped the nearly 20,000-acre Mountain fire in Ventura County this past fall. And they were blowing, too, when a spark of unknown origin ignited the now 23,000 acres of wildfire burning through the suburbs of Los Angeles.

Though steeped in mystery and superstition (writers call them the “devil winds”), the Santa Ana winds are common in Los Angeles during this time of year. (Scientists call them simply “offshore winds.”) The phenomenon is caused by winter’s cold, dry air becoming lodged in the bowl of the Great Basin, where it forms a high-pressure area. That clockwise-moving air wants to escape, and it does so by rushing down and south through the mountain passes to the low-pressure area on the coast: Los Angeles.

The wind can pick up a lot of speed — on Wednesday morning, gusts topped 100 miles per hour in the San Gabriel Mountains. It can also become drier and warmer — by as much as 50 degrees Fahrenheit — as it rushes through the passes toward the coast, which is what gives the Santa Anas their signature warmth, which so many find disquieting.

What makes the Santa Ana winds happening now unique?

For one thing, the current Santa Anas are on the upper end of the spectrum for velocity, which is part of why they have such a significant impact — and cause firefighters so much trouble. For another, there is a “rare placement of upper-level jet stream winds” giving the system a more northerly flow as opposed to the usual north-easterly orientation, Scott Capps, an atmospheric scientist and the head of Atmospheric Data Solutions, a forecasting firm, told me in an email. As a result, “many areas that are typically not impacted by Santa Ana winds were impacted.”

Does climate change affect the Santa Anas?

“Logically, it makes sense that climate change will impact the frequency and characteristics of [the Santa Anas],” Capps told me. However, “due to the complexity of the environment, we cannot blame one single factor for any extreme weather event.” The more obvious connection between the L.A. fires and climate change is the lack of precipitation during what is supposed to be the region’s wet season; some parts of southern California have received just 10% of their normal rainfall since October, making the area ripe for a fire.

Scientists used to think that inland warming would reduce the cold weather-related high pressure in the Great Basin and weaken the Santa Anas. While it does appear that so-called “cold” Santa Anas — caused by air in the Great Basin that is so cold initially that it’s still chilly when it reaches L.A., and which account for about a third of all Santa Anas — are becoming less frequent, the more traditional “warm” winds that are associated with wildfires don’t actually seem to bear out this hypothesis. Instead, they “are spread uniformly over the seven decades of record,” the authors of a 2021 study wrote.

If climate change is doing anything to warm or accelerate Santa Anas, the data would appear to suggest“an increasing potential of warmer and drier [Santa Ana winds] to dry out coastal vegetation and, particularly in anomalously dry winters, enhance the coastal wildfire season even into spring,” the authors went on.

While it’s far too soon to link the California disaster to climate change, the study’s authors now seem prescient: dry vegetation and an unusually dry winter both go far in explaining why this week’s fires are so destructive.

Yellow

You’re out of free articles.

Subscribe today to experience Heatmap’s expert analysis 
of climate change, clean energy, and sustainability.
To continue reading
Create a free account or sign in to unlock more free articles.
or
Please enter an email address
By continuing, you agree to the Terms of Service and acknowledge our Privacy Policy
AM Briefing

DAC Hubs May Be DOA

On Trump’s coal woes, NEPA reform, and Japan’s nuclear plans

A Climeworks facility.
Heatmap Illustration/Climeworks

Current conditions: In the Atlantic, the tropical storm that could, as it develops, take the name Jerry is making its way westward toward the U.S. • In the Pacific, Hurricane Priscilla strengthened into a Category 2 storm en route to Arizona and the Southwest • China broke an October temperature record with thermometers surging near 104 degrees Fahrenheit in the southeastern province of Fujian.

THE TOP FIVE

1. Energy Department looks ready to cancel direct air capture hubs

The Department of Energy appears poised to revoke awards to two major Direct Air Capture Hubs funded by the Infrastructure Investment and Jobs Act in Louisiana and Texas, Heatmap’s Emily Pontecorvo reported Tuesday. She got her hands on an internal agency project list that designated nearly $24 billion worth of grants as “terminated,” including Occidental Petroleum’s South Texas DAC Hub and Louisiana's Project Cypress, a joint venture between the DAC startups Heirloom and Climeworks. An Energy Department spokesperson told Emily that he was “unable to verify” the list of canceled grants and said that “no further determinations have been made at this time other than those previously announced,”referring to the canceled grants the department announced last week. Christoph Gebald, the CEO of Climeworks, acknowledged “market rumors” in an email, but said that the company is “prepared for all scenarios.” Heirloom’s head of policy, Vikrum Aiyer, said the company wasn’t aware of any decision the Energy Department had yet made.

Keep reading...Show less
Blue
Politics

How a Children’s Hospital Became Collateral Damage in the Government Shutdown

Last week’s Energy Department grant cancellations included funding for a backup energy system at Valley Children’s Hospital in Madera, California

Valley Children's Hospital.
Heatmap Illustration/Valley Children's Healthcare, Getty Images

When the Department of Energy canceled more than 321 grants in an act of apparent retribution against Democrats over the government shutdown, Russ Vought, President Trump’s budget czar, declared that the money represented “Green New Scam funding to fuel the Left's climate agenda.”

At least one of the grants zeroed out last week, however, was supposed to help keep the lights on at a children’s hospital.

Keep reading...Show less
Blue
Podcast

How China’s Power Grid Really Works

Rob and Jesse break down China’s electricity generation with UC San Diego’s Michael Davidson.

Xi Jinping.
Heatmap Illustration/Getty Images

China announced a new climate commitment under the Paris Agreement at last month’s United Nations General Assembly meeting, pledging to cut its emissions by 7% to 10% by 2035. Many observers were disappointed by the promise, which may not go far enough to forestall 2 degrees Celsius of warming. But the pledge’s conservatism reveals the delicate and shifting politics of China’s grid — and how the country’s central government and its provinces fight over keeping the lights on.

On this week’s episode of Shift Key, Rob and Jesse talk to Michael Davidson, an expert on Chinese electricity and climate policy. He is a professor at the University of California, San Diego, where he holds a joint faculty appointment at the School of Global Policy and Strategy and the Jacobs School of Engineering. He is also a senior associate at the Center for Strategic and International Studies, and he was previously the U.S.-China policy coordinator for the Natural Resources Defense Council.

Keep reading...Show less