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
Q&A

How Has the Rise of AI Changed the Odds of a Permitting Deal?

Catching up with the American Council on Renewable Energy’s Ray Long.

Ray Long.
Heatmap Illustration/Getty Images

Today’s chat is with Ray Long, CEO of the American Council on Renewable Energy. We first discussed the odds of permitting reform a year and a half ago, for one of the first Q&As in The Fight. Flash forward and we’re still in the same situation, but now also wrestling with added demand for electricity to power data centers. I wanted to talk again about whether he thought the rise of artificial intelligence would increase the odds of some federal deal happening any time soon. The result: a wide-reaching conversation about the future of the electric grid, the struggles to win community buy-in and the sclerotic nature of the U.S. Congress.

The following conversation was lightly edited for clarity.

Keep reading...Show less
Yellow
Hotspots

Ohio Is Waging a Multi-Front Assault Against Data Centers

Plus more of week’s biggest development fights.

The United States.
Heatmap Illustration/Getty Images

1. Ohio — This state might just be the most important flashpoint in the national fight over advanced energy and tech infrastructure.

  • Ohio is now home to one of the fiercest retaliatory strikes against the data center sector from a statewide elected Republican. Last week, Governor Mike DeWine said he was pausing access to the state’s tax exemption request program for all data centers (sans two projects that squeaked in under the wire).
  • In the state legislature, a new select committee on data center development got an earful from aggrieved anti-data center voices this week at their only hearing for public comment. Legislation and regulation feels all but inevitable. As lawmakers debate potential legislation, grassroots organizers opposed to development are gathering signatures in hope of landing a moratorium vote on the ballot this November.
  • Meanwhile, the state Supreme Court struck down permits for the biggest solar project in the state: Oak Run, a large agri-voltaics project backed by a Shell subsidiary.
  • As I previously wrote, the court challenge against Oak Run was a potential harbinger of the extent local opposition would be considered a proxy for “the public interest,” a legal term of art crucial to state energy and power permitting.
  • In a decision overruling the Ohio Power Siting Board, justices wrote the board’s “rationale” on this public interest question “misses the mark” because it failed to include photos or sketches addressing visual concerns raised by locals. The board will now have to reconsider Oak Run and compel new analysis specific to surrounding sightlines.
  • Conflict over large industrial development in Ohio was eminently predictable. Heatmap’s polling and modeling has consistently shown an Obama-Trump voting flip like the one Ohio landed in 2016 as a predictor for potential opposition to building renewable energy. Same goes for the fight over development on farmland — and Ohio is flush with prospective ag property. Knowing renewables-hostile areas are harder for data centers, this would be a likely no-go zone for developers if it wasn’t for existing fiber-optic cable networks.

2. Laramie County, Wyoming — The Cowboy State’s capital city is one of the few to reject a data center moratorium. But tech companies. don’t get your hopes up too high.

Keep reading...Show less
Yellow
Data center protesters.
Heatmap Illustration/Getty Images

The national AI data center moratorium has momentum.

As I’ve been documenting for months here at The Fight, data center opposition is surging across the country. Our latest Heatmap Pro poll puts some very hard numbers behind that picture. More than 7 in 10 Americans oppose new data center construction near where they live, up from just over 4 in 10 last fall. Part of what’s driving that opposition: More than half of respondents hold data centers largely responsible for rising electricity prices, and nearly half are pessimistic about the effect artificial intelligence will have on their lives.

Keep reading...Show less
Yellow