Science

The Next Threat to L.A.? Rainfall That Could Cause Landslides

Published

1 year ago

January 17, 2025

The Next Threat to L.A.? Rainfall That Could Cause Landslides

While winds and flames continued to ravage Los Angeles, small teams began creeping onto the charred soils left in their wake.

Roughly a dozen members of the California Watershed Emergency Response Teams and the United States Forest Service are studying the edges of the Eaton and Palisades fires to determine what patches of land burned most severely. Soon, they’ll issue hazard maps to help people prepare for what comes next: the near-certain threat of floods and landslides that will loom for days, months and even years while the city recovers.

“After a wildfire, the hazard to the public is not over,” said Jeremy Lancaster, California’s state geologist. He and his team spent Wednesday hiking in the steep canyons that flank the San Gabriel and Santa Monica Mountains. When it rains hard enough, the sediment on slopes like these can swiftly tumble downhill onto houses that increasingly push up against the fire-prone foothills.

The two major hazards after a wildfire are flash flooding and post-fire debris flows. While spongy soils typically absorb water, burned soils can become hard packed like concrete, repelling water as a raincoat would. Water then funnels downslope without much, or any, vegetation left after a fire to keep it in check.

Hazard maps use a combination of satellite images and field testing of soils to show where patches of moderately to severely burned soils could make these post-fire risks more likely. Recommendations for emergency services to engineer barricades against the danger accompany the maps.

The Palisades burn map was released on Thursday, and the Eaton map is still under review. Experts said the Palisades fire had mostly low to moderate burn severity, while the Eaton fire was likely to have more moderate to high burn severity.

Debris flows require three ingredients — steep slopes, burned soils and rain — and they’re often more dangerous than floods because the sediment they draw in claws at the landscape, creating a snowball effect that pulls a tumult of trees, vegetation, soil, rocks and anything else in its way.

“A debris flow is like a flood on steroids,” said Jason Kean, a research hydrologist with the United States Geological Survey. “It’s all bulked up with rocks and mud and trees.” While floods often have a longer reach, water churns faster in debris flows, which are less common but more destructive.

After the Thomas fire in 2017, a debris flow in Montecito, Calif., killed 23 people and damaged or destroyed more than 400 homes.

Neither homeowners’ insurance nor federal flood insurance covers the impact to properties of debris flows, which are defined by the Geologic Survey as landslides.

The fire-flood cycle is a long-studied relationship, but scientists say a warming planet has made the post-fire threat more likely. Fires burn bigger and more severely. Rains hit harder and more often. Those changes expand the target area for post-fire hazards, which could increase the size and the frequency of floods and flows.

“The fire scientists are telling us that wildfires are increasing in size and severity,” Dr. Kean said. “From that fact alone, you’re exposing more terrain and making more terrain vulnerable to post-fire problems.”

With a dangerous combination of very steep terrain, lots of sediment, high-fire activity and a lot of people pushed up against the mountains, Los Angeles faces an extreme risk.

“The Los Angeles area and Southern California are the world capital for post-fire debris flows,” Dr. Kean said.

Debris flows are so common in Los Angeles that at the edge of the San Gabriel Mountains, where the Eaton fire burned, the state has carved debris basins to collect waste from major flow events. In Southern California, more than two million people live on alluvial fans, landforms that are conducive to flash floods and debris flows, according to Dr. Lancaster.

The National Weather Service in Los Angeles collaborated with the Geological Survey to start the nation’s first early warning systems for these post-fire hazards in 2005. The geological survey sets a rainfall threshold that could set off landslides, and the Weather Service issues a warning if the rainfall they expect nears or surpasses it.

Jayme Laber, a senior hydrologist with the Los Angeles forecast office, has spent the last two decades issuing such warnings. While there’s still no sign of rain in the seven to 10 day forecast he issued on Wednesday, a garden-variety rainstorm that Angelenos see at least once or twice a year could be enough to kick off the next wave of hazards, which can develop within minutes.

“In a burned area, the kind of rain that would not cause problems would be a really light drizzly rain that just goes on and on,” Mr. Laber said. But at some point this winter, he added, “we’re going to get rainfall that has the potential to cause flash flooding and debris flows in these newly burned areas.”

This video of a small debris flow from 2016, which is close to the site of the current Eaton fire, shows how quickly large objects, like a six-foot boulder, can be sent rushing downhill.

Mr. Laber advised residents to prepare in case of a future evacuation, monitor the forecast and pay attention to local emergency officials if a warning is issued.

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Science

What a Speech Reveals About Trump’s Plans for Nuclear Weapons

Published

1 day ago

February 14, 2026

Press Room

What a Speech Reveals About Trump’s Plans for Nuclear Weapons

Within hours of the expiration last week of the final arms control treaty between Moscow and Washington, the State Department sent its top arms diplomat, Thomas G. DiNanno, to Geneva to lay out Washington’s vision for the future. His public address envisioned a future filled with waves of nuclear arms buildups and test detonations.

The views of President Trump’s administration articulated in Mr. DiNanno’s speech represent a stark break with decades of federal policy. In particular, deep in the speech, he describes a U.S. rationale for going its own way on the global ban on nuclear test detonations, which had been meant to curb arms races that in the Cold War had raised the risk of miscalculation, and war.

This annotation of the text of his remarks aims to offer background information on some of the specialized language of nuclear policymaking that Mr. DiNanno used to make his points, while highlighting places where outside experts may disagree with his and the administration’s claims.

What remains unknown is the extent to which Mr. DiNanno’s presentation represents a fixed policy of unrestrained U.S. arms buildups, or more of an open threat meant to spur negotiations toward new global accords on ways to better manage the nuclear age.

Read the original speech.

New York Times Analysis

Established in 1979 as Cold War arsenals grew worldwide, the Conference on Disarmament is a United Nations arms reduction forum made up of 65 member states. It has helped the world negotiate and adopt major arms agreements.

In his State Department role, working under Secretary of State Marco Rubio, Mr. DiNanno is Washington’s top diplomat for the negotiation and verification of international arms accords. Past holders of that office include John Bolton during the first term of the George W. Bush administration and Rose Gottemoeller during Barack Obama’s two terms.

This appears to be referring to China, which has 600 nuclear weapons today. By 2030, U.S. intelligence estimates say it will have more than 1,000.

Here he means Russia, which is conducting tests to put a nuclear weapon into space as well as to develop an underwater drone meant to cross oceans.

New York Times Analysis

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In this year’s federal budget, the Trump administration is to spend roughly $90 billion on nuclear arms, including basic upgrades of the nation’s arsenal and the replacement of aging missiles, bombers and submarines that can deliver warheads halfway around the globe.

A chief concern of many American policymakers is that Washington will soon face not just a single peer adversary, as in the Cold War, but two superpower rivals, China and Russia.

New York Times Analysis

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The 1987 Intermediate-Range Nuclear Forces Treaty or I.N.F. banned all weapons capable of traveling between 500 and 5,500 kilometers, or 310 and 3,420 miles, whether armed with nuclear or conventional warheads. The Trump administration is now deploying a number of conventionally armed weapons in that range, including a cruise missile and a hypersonic weapon.

The destructive force of the relatively small Russian arms can be just fractions of the Hiroshima bomb’s power, perhaps making their use more likely. The lesser warheads are known as tactical or nonstrategic nuclear arms, and President Vladimir V. Putin of Russia has repeatedly threatened to use them in Ukraine.

Negotiators of arms control treaties have mostly focused on long-range weapons because the delivery vehicles and their deadly warheads are considered planet shakers that could end civilization.

New York Times Analysis

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This underwater Russian craft is meant to cross an ocean, detonate a thermonuclear warhead and raise a radioactive tsunami powerful enough to shatter a coastal city.

The nuclear power source of this Russian weapon can in theory keep the cruise missile airborne far longer than other nuclear-armed missiles.

Russia has conducted test launches for placing a nuclear weapon into orbit, which the Biden administration quietly warned Congress about two years ago.

The term refers to the five permanent members of the United Nations Security Council—China, France, Russia, the United Kingdom and the United States.

New York Times Analysis

« Previous Next »

A top concern of American officials is that Beijing and Moscow might form an alliance to coordinate their nuclear forces. Their joint program to develop fuel for atom bombs is seen as an indication of this emerging threat.

This Trump administration plan is dated November but was made public in December.

Released last year, this Chinese government document sought to portray Beijing as a leader in reducing the global threat of nuclear weapons.

Typically, arms control treaties have not required countries to destroy warheads so their keepers put them into storage for possible reuse. The United States retains something on the order of 20,000 small atom bombs meant to ignite the larger blasts of hydrogen bombs.

An imminent surge centers on the nation’s Ohio-class submarines. The Trump administration has called for the reopening of submarine missile tubes that were closed to comply with the New START limits. That will add as many 56 long-range missiles to the fleet. Because each missile can hold multiple arms, the additional force adds up to hundreds more warheads.

This refers to weapons meant for use on a battlefield or within a particular geographic region rather than for aiming at distant targets. It is often seen as synonymous with intermediate-range weapons.

Here, the talk turns to the explosive testing of nuclear weapons for safety, reliability and devising new types of arms. The United States last conducted such a test in 1992 and afterwards adopted a policy of using such nonexplosive means like supercomputer simulations to evaluate its arsenal. In 1996, the world’s nuclear powers signed a global ban on explosive testing. A number of nations, including the United States and China, never ratified the treaty, and it never officially went into force.

In new detail, the talk addresses what Mr. Trump meant last fall when he declared that he had instructed the Pentagon “to start testing our Nuclear Weapons on an equal basis” in response to the technical advances of unnamed foreign states.

Outside experts say the central issue is not whether China and Russia are cheating on the global test ban treaty but whether they are adhering to the U.S. definition. From the treaty’s start in 1996, Washington interpreted “zero” explosive force as the compliance standard but the treaty itself gives no definition for what constitutes a nuclear explosion. Over decades, that ambiguity led to technical disputes that helped block the treaty’s ratification.

By definition, all nuclear explosions are supercritical, which means they split atoms in chain reactions that become self-sustaining in sufficient amounts of nuclear fuel. The reports Mr. DiNanno refers to told of intelligence data suggesting that Russia was conducting a lesser class of supercritical tests that were too small to be detected easily. Russian scientists have openly discussed such small experiments, which are seen as useful for assessing weapon safety but not for developing new types of weapons.

This sounds alarming but experts note that the text provides no evidence and goes on to speak of preparations, not detonations, except in one specific case.

New York Times Analysis

« Previous

The talk gave no clear indication of how the claims about Russian and Chinese nuclear testing might influence U.S. arms policy. But it repeated Mr. Trump’s call for testing “on an equal basis,” suggesting the United States might be headed in that direction, too.

The talk, however, ended on an upbeat but ambiguous note, giving no indication of what Mr. DiNanno meant by “responsible.” Even so, the remark came in the context of bilateral and multilateral actions to reduce the number of nuclear arms in the world, suggesting that perhaps the administration’s aim is to build up political leverage and spur new negotiations with Russia, China or both on testing restraints.

Science

Notoriously hazardous South L.A. oil wells finally plugged after decades of community pressure

Published

1 day ago

February 14, 2026

Press Room

Notoriously hazardous South L.A. oil wells finally plugged after decades of community pressure

California Gov. Gavin Newsom announced this week that state oil and gas regulators have permanently closed one of the most infamous drill sites in Los Angeles, bringing an end to a decades-long community campaign to prevent dangerous gas leaks and spills from rundown extraction equipment.

A state contractor plugged all 21 oil wells at the AllenCo Energy drill site in University Park, preventing the release of noxious gases and chemical vapors into the densely populated South Los Angeles neighborhood. The two-acre site, owned by the Archdiocese of Los Angeles, is located across the street from several multifamily apartment buildings and less than 1,000 feet from St. Vincent School.

For years, residents and students had repeatedly complained about acrid odors from the site, with many suffering chronic headaches and nosebleeds. The health concerns prompted a community-driven campaign to shut down the site, with some residents even pleading (unsuccessfully) with the late Pope Francis to intervene.

AllenCo, the site’s operator since 2009, repeatedly flouted environmental regulations and defied state orders to permanently seal its wells.

This month, the California Department of Conservation’s Geologic Energy Management Division (CalGEM) finished capping the remaining unplugged wells with help from Biden-era federal funding.

“This is a monumental achievement for the community who have endured an array of health issues and corporate stalling tactics for far too long,” Newsom said in a statement Wednesday. “I applaud the tireless work of community activists who partnered with local and state agencies to finish the job and improve the health and safety of this community. This is a win for all Californians.”

The land was donated to the Catholic Archdiocese of Los Angeles in the 1950s by descendants of one of the city’s early oil barons. Over the decades, the archdiocese leased the land to several oil companies including Standard Oil of California.

Much of the community outcry over the site’s management occurred after AllenCo took over the site in 2009. The company drastically boosted oil production, but failed to properly maintain its equipment, resulting in oil spills and gas leaks.

In 2013, U.S. Environmental Protection Agency officials became sick while inspecting the site. The federal investigators encountered puddles of crude oil on the facility grounds, as well as caustic fumes emanating from the facility, resulting in violations for air quality and other environmental infractions.

In 2020, CalGEM ordered AllenCo to plug the wells after if determined the company had essentially deserted the site, leaving the wells unplugged and in an unsafe condition. AllenCo ignored the order.

In perhaps the most remarkable events in the site’s history, CalGEM officials in 2022 arrived on the site with a court order and used bolt cutters to enter the site to depressurize the poorly maintained oil wells.

The AllenCo wells were prioritized and plugged this week as part of a CalGEM program to identify and permanently cap high-risk oil and gas wells. Tens of thousands of unproductive and unplugged oil wells have been abandoned across California — many of which continue to leak potentially explosive methane or toxic benzene.

Environmental advocates have long fought for regulators to require oil and gas companies to plug these wells to protect nearby communities and the environment.

However, as oil production declines and fossil fuel companies increasingly become insolvent, California regulators worry taxpayers may have to assume the costs to plug these wells. Federal and state officials have put aside funding to deal with some of these so-called “orphaned” wells, but environmental advocates say it’s not enough. They say oil and gas companies still need to be held to account, so that the same communities that were subjected to decades of pollution won’t have to foot the bill for expensive cleanups.

“This is welcome news that the surrounding community deserves, but there is much more work to be done at a much faster pace,” said Cooper Kass, attorney at the Center for Biological Diversity’s Climate Law Institute. “There are still thousands of unplugged and hazardous idle wells threatening communities across the state, and our legislators and regulators should force polluters, not taxpayers, to pay to clean up these dangerous sites.”

Science

Newsom tells world leaders Trump’s retreat on the environment will mean economic harm

Published

2 days ago

February 13, 2026

Press Room

Newsom tells world leaders Trump’s retreat on the environment will mean economic harm

SACRAMENTO — Gov. Gavin Newsom told world leaders Friday that President Trump’s retreat from efforts to combat climate change would decimate the U.S. automobile industry and surrender the future economic viability to China and other nations embracing the transition to renewable energy.

Newsom, appearing at the Munich Security Conference in Germany, urged diplomats, business leaders and policy advocates to forcefully stand up to Trump’s global bullying and loyalty to the oil and coal industry. The California governor said the Trump administration’s massive rollbacks on environmental protection will be short-lived.

“Donald Trump is temporary. He’ll be gone in three years,” Newsom said during a Friday morning panel discussion on climate action. “California is a stable and reliable partner in this space.”

Newsom’s comments came in the wake of the Trump administration’s repeal of the endangerment finding and all federal vehicle emissions regulations. The endangerment finding is the U.S. government’s 2009 affirmation that planet-heating pollution poses a threat to human health and the environment.

Environmental Protection Agency administrator Lee Zeldin said the finding has been regulatory overreach, placing heavy burdens on auto manufacturers, restricting consumer choice and resulting in higher costs for Americans. Its repeal marked the “single largest act of deregulation in the history of the United States of America,” he said.

Scientists and experts were quick to condemn the action, saying it contradicts established science and will put more people in harm’s way. Independent researchers around the world have long concluded that greenhouse gases released by the burning of gasoline, diesel and other fossil fuels are warming the planet and worsening weather disasters.

The move will also threaten the U.S.’s position as a leader in the global clean energy transition, with nations such as China pulling ahead on electric vehicle production and investments in renewables such as solar, batteries and wind, experts said.

Newsom’s trip to Germany is just his latest international jaunt in recent months as he positions himself to lead the Democratic Party’s opposition to Trump and the Republican-led Congress, and to seed a possible run for the White House in 2028. Last month Newsom traveled to the World Economic Forum in Davos, Switzerland, and in November to the U.N. climate summit in Belém, Brazil — mocking and condemning Trump’s policies on Greenland, international trade and the environment.

When asked how he would restore the world’s confidence in the United States if he were to become president, Newsom sidestepped. Instead he offered a campaign-like soliloquy on California’s success on fostering Tesla and the nation’s other top electric vehicle manufacturers as well as being a magnet for industries spending billions of dollars on research and development for the global transition away from carbon-based economies.

The purpose of the Munich conference was to open a dialogue among world leaders on global security, military, economic and environmental issues. Along with Friday’s discussion on climate action, Newsom is scheduled to appear at a livestreamed forum on transatlantic cooperation Saturday.

Andrew Forrest, executive chairman of the Australia-based mining company giant Fortescue, said during a panel Friday his company is proof that even the largest energy-consuming companies in the world can thrive without relying on the carbon-based fuels that have driven industries for more than a century. Fortescue, which buys diesel fuel from countries across the world, will transition to a “green grid” this decade, saving the company a billion dollars a year, he said.

“The science is absolutely clear, but so is the economics. I am, and my company Fortescue is, the industrial-grade proof that going renewable is great economics, great business, and if you desert it, then in the end, you’ll be sorted out by your shareholders or by your voters at the ballot box,” Forrest said.

Newsom said California has also shown the world what can be done with innovative government policies that embrace electric vehicles and the transition to a non-carbon-based economy, and continues to do so despite the attacks and regressive mandates being imposed by the Trump administration.

“This is about economic prosperity and competitiveness, and that’s why I’m so infuriated with what Donald Trump has done,” Newsom said. “Remember, Tesla exists for one reason — California’s regulatory market, which created the incentives and the structure and the certainty that allowed Elon Musk and others to invest and build that capacity. We are not walking away from that.”

California has led the nation in the push toward EVs. For more than 50 years, the state enjoyed unique authority from the EPA to set stricter tailpipe emission standards than the federal government, considered critical to the state’s efforts to address its notorious smog and air-quality issues. The authority, which the Trump administration has moved to rescind, was also the basis for California’s plan to ban the sale of new gasoline-powered cars by 2035.

The administration again targeted electric vehicles in its announcement on Thursday.

“The forced transition to electric vehicles is eliminated,” Zeldin said. “No longer will automakers be pressured to shift their fleets toward electric vehicles, vehicles that are still sitting unsold on dealer lots all across America.”

But the efforts to shut down the energy transition may be too little, too late, said Hannah Safford, former director of transportation and resilience at the White House Climate Policy Office under the Biden administration.

“Electric cars make more economic sense for people, more models are becoming available, and the administration can’t necessarily stop that from happening,” said Safford, who is now associate director for climate and environment at the Federation of American Scientists.

Still, some automakers and trade groups supported the EPA’s decision, as did fossil fuel industry groups and those geared toward free markets and regulatory reform. Among them were the Independent Petroleum Assn. of America, which praised the administration for its “efforts to reform and streamline regulations governing greenhouse gas emissions.”

Ford, which has invested in electric vehicles and recently completed a prototype of a $30,000 electric truck, said in a statement to The Times that it appreciated EPA’s move “to address the imbalance between current emissions standards and consumer choice.”

Toyota, meanwhile, deferred to a statement from Alliance for Automotive Innovation president John Bozzella, who said similarly that “automotive emissions regulations finalized in the previous administration are extremely challenging for automakers to achieve given the current marketplace demand for EVs.”