Fire and wind are certain to shape the future of Los Angeles as the world warms.

Los Angeles had started taking steps to prepare. But there are lessons it can learn from other cities adapting to extreme fire weather: managing yards; taking care of neighbors; making it easier to get out of harm’s way.

One big challenge, among many, is that plans like these need to be widely adopted. One home is only as safe as the home next door. “If your neighbor doesn’t do anything, and you do, if that home burns it will create so much radiant heat, yours will burn too,” said Kimiko Barrett of Headwaters Economics in Bozeman, Mont., a company that advises cities on reducing wildfire damage risk.

Neighbors matter. Building codes and zoning rules matter. But perhaps most of all, money matters. Building for an age of fire can be expensive, and often out of reach for many homeowners living in fire-prone communities.

Look hard at the landscape

Boulder County, Colo., has learned some big lessons from recent fires.

Pine needles and debris around a house quickly spread flames. Juniper bushes explode in fire. In fact, county officials call junipers “gasoline plants.” Firewood stuffed under a deck can ignite and destroy a house.

The county has spent several years persuading people to clear debris and rip out junipers. Voters have agreed to a sales tax hike to help pay for it.

Los Angeles has its own problem plant: palms. Many palm species, once they catch fire, are very hard to put out. In fire-prone areas, they should be avoided entirely, according to the Los Angeles County fire department.

San Diego county prohibits greenery — even shrubs — around a five foot perimeter of a building and requires that tree canopies be at least 10 feet away.,

Berkeley, Calif., sends fire inspectors into its most fire-prone neighborhoods to suss out signs of danger: dead brush less than five feet from a house; flammable vegetation that leans over the fence line and threatens a neighbor’s property; high shrubs that can send flames racing up a tree.

There are constraints. Live oaks are protected by law, which means they can’t be cut down. And local communities like Berkeley are still waiting for California state officials to issue regulations to implement a 2023 law designed to minimize fire damage by prescribing landscape-management standards. The city is due to tighten its regulations in the coming weeks, requiring homeowners to keep a five-foot fireproof perimeter around every house in the most fire-prone neighborhoods in the hills. That means no shrubs, no propane tanks, no wood mulch. Violations will be fined; the City Council has yet to determine how much.

“If I can hold a lighter to it and it can smoke and flame, it shouldn’t be there,” said Colin Arnold, the assistant fire chief responsible for the city’s most fire-prone areas on the edge of the wilderness, known as the wildland urban interface

Build safer houses

Houses are flammable, but it’s possible to make them less flammable.

Concrete, stucco, and engineered wood are better than old-fashioned wood frames. A few architects, including Abeer Sweis, in Santa Monica, work with compressed soil, also known as rammed earth, which offers both protection from fire and avoids the emissions of concrete. Roofs made of clay tiles, concrete or metal hold up well to flames. Laminated glass windows can reduce the radiant heat that presses up against a house during a fire.

Design matters, too. Eaves and overhangs can trap embers, which is why architects building in fire-prone areas like them to be sealed. At a time when insurance coverage is becoming increasingly hard to procure in fire-prone communities, Mitchell Rocheleau, an architect based in Irvine, Calif., says fortifying your home is a “physical insurance policy.”

Vents are frequent culprits. . Low-cost fixes, like fire-resistant vents with mesh screens, can keep big embers from flying in, but they’re not always effective, Ms. Sweis said, which is why she prefers vents that are coated with a material that melts in the heat and closes up.

Building codes increasingly mandate noncombustible roofs and siding. (California has among the strictest.) The problem, though, is that most homes in the United States were built before modern building codes. Upgrading an existing house for the age of fire means getting rid of flammable siding and roofs. That’s an expensive proposition.

Boast about improvements

Think of it as a fire-smart version of keeping up with the Joneses.

Boulder County has a way for homeowners to get certified by a county program, Wildfire Partners, for fireproofing practices like junking junipers, choosing less flammable shrubs, installing a fire-resistant roof or slathering fire-resistant sealant on a deck.

Certification comes with a yard sign to display. It’s a way to nudge others in the neighborhood to adopt similar practices.

There’s also a potential reward. Certification can be a way to not lose homeowner’s insurance, which is increasingly a risk in many communities in the American West. “The cost of retrofitting is very real,” Ashley Stolzmann, a county commissioner said. “The cost of losing insurance is also very real.”

Upgrade dangerous power lines

Power lines and utility poles have been responsible for some of California’s most destructive fires in recent years.

Much of that infrastructure was built in the 1960s and 1970s and is in urgent need of repair. Utilities have faced a barrage of lawsuits in the aftermath of some of those fires, including in recent days when residents of Altadena sued Southern California Edison claiming that the utility’s equipment set off the Eaton Fire that destroyed 5,000 buildings in the area. (Edison said it is investigating the cause of the fires.)

A range of fixes are possible, from fire-resistant poles to burying electricity lines (very expensive) to covering them in a protective layer (less expensive but less safe).

The Bipartisan Infrastructure Law set aside $3.5 billion for electricity grid upgrades. That’s a fraction of the $250 billion price tag of the latest Los Angeles fires.

Rethink roads

Cul-de-sacs and narrow, winding streets are a hallmark of many neighborhoods pressed up against wilderness, including the Berkeley Hills. That’s a problem when people need to get out, and first responders need to get in.

“There’s nowhere to put new roads,” Mr. Arnold said. “It’s a very densely packed community built without evacuation in mind.”

If you can’t widen roads, you can keep them clear for first responders to get in and out. The Los Angeles Fire Department prohibits street parking in some neighborhoods on windy days, when fire risk is high.

Rancho Santa Fe, a wealthy suburb of San Diego, has tried to solve the problem by keeping most of its residential roads clear at all times. No street parking is allowed if the street isn’t wide enough for fire trucks to get in and out.

Know when to leave

Bushfires have long been common in hot, dry southeastern Australia. But none scarred its people like the Black Saturday fires that broke out in Victoria state in February, 2009. The blazes killed more than 170 people and led to a rewriting of the state’s evacuation protocols.

On days of high fire risk, people who live in forested communities are encouraged to leave their homes before there are signs of smoke and flame. Warnings are broadcast on television.

Residents are encouraged to have the official state-government emergency-preparedness app, which highlights what areas should empty out when. A look at the app on a recent Thursday morning showed 10 notices across the state, from “leave immediately” warnings in some places to “monitor conditions” elsewhere.

Los Angeles residents, by contrast, received erroneous evacuation warnings by text message on the some of the worst fire days. More reliable was a private app built by a nonprofit group.

“We want people making good decisions before the fire rather than bad decisions during the fire,” said Luke Heagerty, a spokesman for the state control center.

A handful of schools and fire stations are designated as community fire refuge facilities. And for those people who stay behind until a fire reaches their homes, there is the ominously named Bushfire Place of Last Resort. Usually it’s an open field with no trees or structures to catch fire. But as the county fire authority starkly warns on its website, the Bushfire Place of Last Resort sites “do not guarantee safety.”

Build more homes

Los Angeles has long faced an acute need for more housing. For years, it’s met the demand by allowing development in fire-prone areas and allowing homeowners to rebuild after fires have swept through those areas.

The latest fires supersized the need. An estimated 10,000 homes were destroyed, leaving tens of thousands of people in need of shelter and driving up rents and home prices in one of the country’s most expensive real estate markets.

And so among the toughest choices facing Los Angeles now is where to build homes that won’t easily go up in flames.

“You have two options, both of which are politically very difficult, especially right after the fires,” said Michael Manville, a professor of urban planning at the University of California Los Angeles. One is to restrict development in fire-prone areas. The other is to allow more dense housing in less hazardous areas in the flatlands, in neighborhoods zoned for single-family homes. That’s been “a political non-starter,” Mr. Manville said.

Lifesaving health initiatives and medical research projects have shut down around the world in response to the Trump administration’s 90-day pause on foreign aid and stop-work orders.

In Uganda, the National Malaria Control Program has suspended spraying insecticide into village homes and ceased shipments of bed nets for distribution to pregnant women and young children, said Dr. Jimmy Opigo, the program’s director.

Medical supplies, including drugs to stop hemorrhages in pregnant women and rehydration salts that treat life-threatening diarrhea in toddlers, cannot reach villages in Zambia because the trucking companies transporting them were paid through a suspended supply project of the United States Agency for International Development, U.S.A.I.D.

Dozens of clinical trials in South Asia, Africa and Latin America have been suspended. Thousands of people enrolled in the studies have drugs, vaccines and medical devices in their bodies but no longer have access to continuing treatment or to the researchers who were supervising their care.

In interviews, more than 20 researchers and program managers described the upheaval in health systems in countries across the developing world. Most agreed to be interviewed on the condition that their names not be published, fearing that speaking to a reporter would jeopardize any possibility that their projects might be able to reopen.

Many of those interviewed broke down in tears as they described the rapid destruction of decades of work.

The programs that have frozen or folded over the past six days supported frontline care for infectious disease, providing treatments and preventive measures that help avert millions of deaths from AIDS, tuberculosis, malaria and other diseases. They also presented a compassionate, generous image of the United States in countries where China has increasingly competed for influence.

The State Department and U.S.A.I.D. did not respond to requests for comment.

There will now be no one to take custody of millions of dollars’ worth of supplies for vital oxygen systems, purchased for programs funded by U.S.A.I.D. that support health clinics in some of the world’s poorest countries. The shipments, now in transit, are scheduled to reach ports in the coming days, but employees of those programs have been ordered to stop work.

On Tuesday night, Secretary of State Marco Rubio issued an exemption to the funding freeze for “lifesaving humanitarian assistance,” including what a State Department memo called “core lifesaving medicine.” However, shuttered H.I.V. and tuberculosis treatment programs have been told by their contacts at U.S.A.I.D. that they cannot resume work until they receive written instruction that the waiver applies specifically to them.

Also on Tuesday, a federal judge blocked the freeze until Feb. 3. But in practice, most U.S.A.I.D. country offices and programs are proceeding as if the freeze remains in place.

They have been unable to obtain clarification on whether and when their work can continue because their assigned contacts at U.S.A.I.D. have either been fired or furloughed, or are under strict instructions to not talk to anyone.

Despite the court order, thousands of people have already lost their jobs as a result of the freeze. About 500 U.S.-based employees of U.S.A.I.D. were fired. In countries from India to Zimbabwe, staff members for health projects were immediately fired. An organization called the International Centre for Diarrhoeal Disease Research, Bangladesh, which does research on a top killer of children, laid off more than 1,000 employees this week.

If the waiver announced by Mr. Rubio does not apply to their work — as is likely because it is expected to exempt only a narrow scope of activities — many nonprofit groups will not have enough funds to pay their employees or maintain supplies. Already, organizations that rely on U.S.A.I.D. funds have not been able access any money, even for reimbursement of expenses already incurred.

Two-thirds of the staff of the President’s Malaria Initiative, an organization founded by former President George W. Bush that is the largest donor to anti-malaria programs and research worldwide, have been fired. Those employees were contract staff members, because the agency had longtime hiring freezes for permanent positions, and included some of the most senior and respected scientists working on malaria control in the world.

While the interruption of H.I.V. treatment has prompted an outcry, the suspension of malaria work also immediately jeopardizes lives, said a scientist who was a senior staff member at the President’s Malaria Initiative for a decade and was fired on Tuesday.

Malaria interventions in Africa are carefully planned around rainy seasons, the time of which varies by region. Houses are sprayed with insecticide, and children are treated with an antimalarial medication during peak malaria transmission times.

“You could open the funding floodgates again tomorrow and you will still have children dying months from now because of this pause,” the scientist said.

More than 50 million children received preventative drugs before the rainy season last year.

The delivery of rapid tests and malaria drugs into Myanmar, where cases of malaria increased nearly tenfold to 850,000 in 2023 (the most recent figures available) from 78,000 in 2019, has been frozen. Some organizations now have no workers left to distribute the supplies even if they were to arrive.

In some parts of the country, more than 40 percent of cases are of a type of malaria that is often deadly in children under the age of 5. Malaria drugs would seem to qualify under the stipulation of “lifesaving humanitarian assistance, including essential medicines” included in the waiver, but in the absence of certainty, no one has been bold enough to try to free the drugs now stuck at the Thai border.

Some 2.4 million anti-malaria bed nets are sitting in production facilities in Asia, manufactured to fulfill U.S.-funded orders and bound for countries across sub-Saharan Africa. Those contracts are now frozen, because the U.S.A.I.D. subcontractor that bought them is not allowed to talk to the manufacturer under the terms of the freeze. Contracts for eight million more nets are now in limbo, an executive with the manufacturer said.

U.S.A.I.D.’s largest project is called the global health supply chain, an effort to streamline procurement of supplies for H.I.V., malaria, maternal health and other key areas, to make the system more efficient and save money. It operates in more than 55 countries where, in many cases, it supplies the bulk of key medicines. Now its global web of staff has been ordered to stop work except for essential tasks, like guarding commodities in warehouses.

In Zambia, U.S.A.I.D. supports the bulk distribution of public health products, using the private trucking industry to move medicines from a central supply depot to seven regional hubs, from which they are taken by truck, motorbike and boat to rural health centers. It’s part of the extensive U.S. support of the health system in Zambia, one of the world’s poorest countries, and over time it has been working to build up the supply chain capacity of the government.

Since the stop-work order was issued last Saturday, all of the vehicles transporting health products have been stopped. “They have effectively paralyzed the Zambian public health sector by pulling out so abruptly,” said one consultant who worked with the program. Similar U.S.-funded systems, now frozen, also moved a major share of basic medical supplies in Mozambique, Nigeria, Malawi and Haiti.

In East Africa, medical researchers working on projects to find ways to stop transmission of H.I.V. and develop more effective contraception have found themselves foundering for explanations to give to participants in their clinical trials.

“We have women testing vaginal rings, they already have the rings in them, people who got an injectable for H.I.V. prevention — when you say ‘stop,’ what happens to them?” said an H.I.V. researcher who is an investigator on a number of clinical trials. “We have an ethical obligation to people who volunteer for trials.”

Apoorva Mandavilli contributed reporting.

Horst Köhler, who became Germany’s president after being a financial engineer behind the reunification of Germany and the creation several decades later of the euro currency, died on Saturday in Berlin. He was 81.

The German president’s office, in a statement on behalf of Mr. Köhler’s family, said he died after a short illness.

Despite having served as managing director of the International Monetary Fund, Mr. Köhler was little known politically in Germany before becoming the country’s president in 2004. Yet Mr. he rose to popularity after taking office, serving much of his nearly six years alongside Chancellor Angela Merkel.

Mr. Köhler advocated transforming Germany into “a land of ideas” that would shape its own future and act as a force for good on the global stage. He called for bolder domestic economic reforms, and a more confident position internationally. In his May 2004 acceptance speech, he said that “Germany has to fight for its place in the 21st century.”

But his bold statements, such as questioning whether the unequal living standards in the former East and West Germany could ever be evened out, broke taboos in the German political establishment and came at a cost.

In 2010, a year into his second term, Mr. Köhler resigned abruptly amid a barrage of criticism over remarks he made about German soldiers serving in Afghanistan and on peacekeeping missions. His comments, made during a visit to Afghanistan, that German soldiers were deployed to protect German economic interests, drew ire from political opponents who were calling for the withdrawal of his country’s forces from Afghanistan.

It was the first time in four decades that a German president had quit the post — although his successor, Christian Wulff, would also resign, in his case over accusations of improper ties to businesspeople after less than two years in office.

Mr. Köhler’s exit from the political arena was a political blow to Ms. Merkel, his ally and close friend. The re-election of Mr. Köhler, a member of her Christian Democratic Union party, a year earlier had been considered a show of party solidarity as Ms. Merkel faced her own re-election in a fractured political space.

Horst Köhler was born on Feb. 22, 1943, in Skierbieszow, Poland. He was the seventh of eight children, according to his official biography. During World War II, his family fled Soviet troops, settling in a town near Leipzig, Germany. Nine years later, they fled again after the 1953 East German uprising, an anti-Soviet revolt. They lived in several refugee camps before settling in Ludwigsburg, West Germany.

After completing school and military service, Mr. Köhler studied economics at the University of Tübingen, graduating in 1969. He went on to obtain a Ph.D. in economics from the university in 1977. A year earlier, he had begun working as a civil servant at the economics ministry in Bonn, which was then the capital of West Germany.

As Germany grappled with its reunification in the early 1990s, Mr. Köhler held a senior position in the country’s finance ministry. During that time, he was one of the chief negotiators of the 1992 Maastricht Treaty, which created the euro.

From 1993 to 1998, he led the German Savings Bank Association, an umbrella organization that oversees a network of German banks. He then headed the European Bank for Reconstruction and Development, which helped Germany and other countries transition to an open market at the end of the Cold War. He also served as an adviser to Chancellor Helmut Kohl.

Starting in May 2000, Mr. Köhler worked for four years as managing director of the International Monetary Fund, where he endorsed a view of globalization that was more inclusive of developing nations.

Still, he remained relatively unknown to the German public, and in 2004 he became Germany’s president despite not having built a career as a party politician.

After his presidency, he shifted his focus to humanitarian work, through a foundation with his wife, Eva Luise Köhler, that focused on development in Africa and climate change.

Mr. Köhler is survived by his wife; their daughter, Ulrike; a son, Jochen; and four grandchildren.

Sick and wounded people left Gaza for Egypt through the Rafah border crossing on Saturday for the first time in nine months under a key provision of the cease-fire agreement between Israel and Hamas.

But officials in the Gaza Health Ministry said that only 50 of the thousands of ill and injured people in need of treatment abroad would be able to cross on Saturday.

Al Qahera News, an Egyptian state-owned TV channel, live-streamed ambulances arriving at Egypt’s side of the crossing, carrying some of the ill and injured.

The crossing had been closed after Israel invaded Rafah, the southernmost city in Gaza, in May. The war has devastated the health system in Gaza, leaving the hospitals still in service struggling to provide care.

Israel’s war in Gaza has caused immense destruction to medical facilities in the territory, including Al-Shifa Hospital in Gaza City. Israeli officials have accused Hamas of using a number of medical facilities for military purposes and have said that a raid on Al-Shifa in November 2023 revealed a stone-and-concrete tunnel shaft below the facility. Hamas has denied Israel’s accusations.

Before Israel took over the crossing, tens of thousands of the sick and wounded Palestinians and foreigners escaping the war left through the passageway. Rafah was also a crucial entry point for trucks carrying aid into Gaza.

An appendix to the cease-fire agreement between Israel and Hamas says that 50 wounded militants will be allowed to leave Gaza daily after receiving Israeli and Egyptian approvals.

Under the agreement, the number of ill and injured people crossing through Rafah will eventually be increased, restrictions will be lifted and the movement of goods and trade will restart. But the terms did not specify when such changes would go into effect.

The World Health Organization said 37 patients, including 34 children, were evacuated through Rafah on Saturday. It was unclear whether any wounded militants also left.

Rik Peeperkorn, the top World Health Organization official for Gaza and the Israeli-occupied West Bank, described Saturday’s evacuation as a positive step, but he said the pace must be increased through all possible exit routes. Some 12,000 to 14,000 people require treatment outside Gaza for severe injuries and chronic illnesses, he said.

Saed Abu Aita, 44, an injured Palestinian in central Gaza, said the small number of people who left on Saturday gave him cause to worry that he may have to wait months, if not longer, to receive care.

“It’s so frustrating and depressing,” he said. “Why is the world so unfair for us?”

Mr. Abu Aita said a fragment of shrapnel penetrated his rib cage when an Israeli airstrike hit his hometown, Jabaliya, in northern Gaza in October 2023. For more than a year, he said, he has failed to find a doctor in Gaza who can remove the fragment.

Hamas had overseen the Palestinian side of the border between Gaza and Egypt until Israel’s invasion of Rafah.

The crossing is being reopened with a new security arrangement between Israel, Egypt and the internationally backed Palestinian Authority, Hamas’s rival, according to Israeli, Palestinian and European officials who spoke on the condition of anonymity to discuss the sensitive diplomacy.

Israel has resisted the notion that the Palestinian Authority would control postwar Gaza, despite the urging of the former Biden administration in Washington. President Trump’s vision for who might rule the enclave after the conflict remains unclear.

On Jan. 21, the office of Benjamin Netanyahu, the Israeli prime minister, said that the “practical involvement of the Palestinian Authority” at the crossing would be only “its stamp on the passports.” Israeli forces would remain “positioned around the crossing” and no one would be allowed through without the approval of Israel’s security services, the prime minister’s office said at the time.

Brig. Gen. Louay Arzeikat, a spokesman for the Palestinian Authority’s police, has said that a number of unarmed members of the Authority’s officers would be working at the crossing under the command of Maj. Gen. Allam al-Saqa, the chief of the police based in the city of Ramallah in the Israeli-occupied West Bank.

He has said that the police’s role there would include administrative tasks, namely checking and stamping passports.

While Hamas wrested control of Gaza from the Palestinian Authority in 2007, the Palestinian Authority still has some active employees in Gaza.

Nick Cumming-Bruce, Aaron Boxerman and Johnatan Reiss contributed reporting.