Following U.N. protocol, this year's host nation — Azerbaijan — issued the invite.

It's not a full-blown invitation. Because the U.N. does not recognize the Taliban as the official government of Afghanistan due to its repressive policies, the Afghan delegates — members of the National Environmental Protection Agency (NEPA — cannot participate in decision-making events.

Nonetheless, the Taliban has said it is eager to participate. "The Afghan delegation will discuss strengthening international cooperation in the field of environmental protection and climate change," stated a Taliban press release prior to the U.N. event.

Afghan climate scientists and activists, even those critical of the Taliban, welcome this development. "I consider it a very important move because it paves the path to the negotiation with climate change funds, which halted their [Afghan] projects in the past three years," says Assem Mayar, a water resources expert and former lecturer at Kabul Polytechnic University.

"Afghanistan is not officially in the agenda, but having NEPA delegates as observers makes a difference," says Abdulhadi Achakzai, a climate activist with a Kabul-based environmental nonprofit who participated in the summit as an observer.

"Their participation initiates a trust-building effort between international stakeholders," he says, which is imperative if the world "is committed to combating the climate crisis."

A hard-hit country

Afghanistan is among the countries worst impacted by climate change, according to the U.N.; droughts and extreme temperatures have displaced hundreds of thousands of people in recent years.

In 2019, Afghanistan was ranked sixth among countries most affected by climate impacts on the Global Climate Risk Index. And it is among the least prepared to cope with the crisis according to the Notre Dame Global Adaptation Index.

And funding from international groups has been largely halted — part of the sanctions levied to protest Taliban policies that restrict human rights and women's rights.

Since the Taliban takeover, Mayar said climate adaptation projects worth $826 million have been suspended, reducing the capacity of Afghans to respond to increasing climate disasters, including irrigation projects and renewable energy.

Meanwhile, climate shocks have continued to batter Afghans. The country is currently experiencing its third consecutive drought in three years, punctuated by periods of deadly flash floods. According to U.N. data, about 120,000 people were affected by flash flooding and mudslides across the country so far this year.

More specifically, extreme weather — including droughts, extreme temperature, floods, landslides, avalanches and storms— displaced at least 38,000 people in the first half of this year. Save The Children reports about half of those were children.

"Mass migration is, in fact, one major concern and consequence of climate shocks," says Najibullah Sadid, an Afghan climate researcher from the University of Stuttgart. "People will abandon their land and even the country in search of livelihood."

The poppy problem

Severe droughts can also disrupt agriculture, which is the primary occupation in Afghanistan, driving farmers to turn to drought-resistant poppy cultivation instead of food crops. Poppy crops fetch higher prices, and so despite the Taliban's ban, Afghanistan has been among the leading producers.

Sadid says he worries if more fields are dedicated to growing poppies instead of food crops, the food shortage will only worsen.

The majority of the country already lives in poverty. And as climate change is expected to bring increasingly frequent and severe disasters, many Afghans face serious risk.

Achakzai hopes to communicate the urgency of the crisis to stakeholders at the COP summit, which ends on Friday. Climate activists from Afghanistan organized a side event on Wednesday, where Afghan scientists and civilians spoke about the climate stresses facing Afghans.

Various international agencies attended, says Achakzai, who observed some positive changes in international stakeholders' attitudes towards Afghanistan. 

"We hope the participants were [persuaded into] thinking that they can work with the Taliban to fight against the climate change crisis," he says.

Running out of water

Extreme drought has exacerbated the challenge of finding drinking water in many communities, Achakza says. "Underground water tables, which most Afghans rely on, are drying faster than they can be replenished."

In a survey in Kabul conducted by Achakzai's organization, Environmental Protection, Training and Development Organization, researchers found that many communities were digging deeper wells to access groundwater — the primary source of water in the Afghan capital.

Additionally, the study found that many people had migrated to Kabul, abandoning their land and agriculture due to lack of water. But in the city, they find that water isn't exactly plentiful.

An October 2022 feasibility report from the Afghan Ministry of Water and Energy confirmed that the current underground water levels only meet about 40% of the city's expanding needs.

As a result, families, especially children, spend considerable time and effort to procure water, "often having to walk for miles everyday, only to find water in contaminated sources or buy them from private tankers," Achakzai says.

The next year is predicted to be drier than average, Mayar says, "and will result in more droughts in the country." A USAID-funded global network called the Famine Early Warning Systems confirmed this prediction with below average precipitation expected in coming months.

What next for Afghanistan?

With these predictions of prolonged droughts, Achakzai says it's imperative that the international community work to engage the current Afghan government to mitigate the impact of climate change.

Mayar agrees it's critical for the world to find a way to work with or around the Taliban because the loss of international aid has been devastating. The U.S., for instance, reduced its financial support to humanitarian projects in the country from from $1.26 billion in 2022 to $377 million in 2023. What's more, many countries limit aid that can be sent to Afghanistan to only humanitarian needs and won't fund development projects.

Mayar says developing a decentralized system that doesn't require Taliban involvement or approval to deliver aid could help support much-needed projects in the country.

"I propose the accreditation of [Afghan] national NGOs [by international climate fund donors] to receive and implement projects within communities," he says. "In a scenario where the government isn't recognized, such a mechanism could be very helpful in ensuring climate finances reach those affected."

The alternative — isolating Afghanistan from climate action — is grim, says these Mayar. "If we fail to facilitate a mechanism to help these communities, not only will the Afghan civilians bear the heaviest cost of climate change, but the impact of it will be felt across its borders."

Sadid agrees. "If the world is sincere with Afghans, they will find a way to deliver climate funds to Afghanistan, as they found ways to deliver emergency aid in the last three years," he said, adding that "ignoring Afghanistan's climate crisis could prove expensive to the world."

Ruchi Kumar is a journalist who reports on conflict, politics, development and culture in India and Afghanistan. She tweets at @RuchiKumarRuchi Kumar is a journalist who reports on conflict, politics, development and culture in India and Afghanistan. She tweets at @RuchiKumar

NASA Earth Observatory captured the image from its Landsat 8 satellite a day after the historic downpour. It showed parts of the eastern province of Valencia submerged in floodwaters. Meanwhile, the channel of the Turia river and the L'Albufera coastal wetlands were filled with the sediment-laden deluge.

An image of Valencia, Spain on Oct. 25, 2022, taken from NASA's Landsat 8 satellite.

Lauren Dauphin/NASA Earth Observatory

The flood was one of the deadliest weather events in modern Spanish history. Climate scientists say they see a clear connection between the flash flood and human-caused global warming, adding that climate change made this week's rainfall heavier and twice as likely.

Across Valencia, areas exceeded 11 inches of rain. One area that was particularly hard hit was the town of Chiva near Valencia, which accumulated nearly 20 inches in the span of 8 hours — the equivalent to what it usually receives in an entire year, according to Spain's meteorological agency.

Rescue teams are still searching for dozens of missing individuals, but their efforts, along with recovery operations, have been hindered by the wreckage left in the wake of the flood. Photos and videos from Valencia shows cars stacked on top of each other, streets filled with debris and people's belongings covered in brown mud.

Maria Isabel Albalat, the mayor of one of the impacted towns, Paiporta, said that many streets were still blocked, so rescuers could not fully access her town. She added that when they do get access to a location where one person has been reported dead, they end up discovering three or four bodies.

Prime Minister Pedro Sánchez said the government will deploy 5,000 more troops and 5,000 additional police officers to the region. Meanwhile, local authorities are facing criticism for failing to respond sooner.

There had been some warnings to Valencia residents in the days leading up to the storm but the direct alert to people's cellphones — that typically comes from the regional government of Valencia — came the night of the flash floods just past 8 p.m. By that time, floodwaters had risen up to 6 feet in some areas. The phone alert also came during rush hour in Spain while most people were on their way home.

Case numbers had been rising for years before that, though. Now, a new study awaiting peer review suggests that climate change has likely played a significant role in the expansion of the disease from 1995 to 2014, according to an analysis presented in November at the American Society of Tropical Medicine and Hygiene conference in New Orleans. Over that time period, climate change increased the caseload by roughly 20% across the 21 countries in the study — all places where dengue fever was already established, like Indonesia, India and Brazil.

The numbers could skyrocket with further climate change, even beyond the record-breaking case numbers from the past few years, says Erin Mordecai, an infectious disease expert at Stanford University and one of the authors of the new analysis.

"Many of the places in the study region are going to more than double their projected dengue incidence" if human-caused climate change continues to aggressively heat up the planet, she says. But the growth could be contained — not stopped, but at least minimized — if climate action keeps global temperatures in check, she stresses.

Dengue fever is the most common tropical disease in the world. In about a quarter of cases, it can drive painful fever and the sensation of aching joints and bones leads to its common name "breakbone fever." In a small percentage of cases — and most often when someone contracts the disease for a second time — it can be fatal.

Millions of cases of dengue fever play out every year worldwide. But there is currently no commonly available vaccine for adults, and little beyond palliative care to manage the disease once contracted.

Climate fingerprints on dengue fever

Dengue fever is spread between people by two species of mosquitoes, Aedes albopictus and Aedes aegypti.

"Mosquitoes are exothermic," or cold-blooded, Mordecai explains. "So when the temperature gets warmer, everything that their body does speeds up."

Dengue fever is spread by two species of mosquito. Adult females of one of those species, Aedes albopictus, are examined under a microscope. Each species thrives under particular weather conditions. Climate change is expanding those ideal zones into many new parts of the world, increasing the number of cases.

Kevin Frayer/Getty Images

Mosquitoes grow faster. They more effectively replicate the virus in their guts. They even bite more aggressively as temperatures warm toward those ideal levels.

Previous research in laboratories showed that those species of mosquitoes thrived within a predictable temperature range. For Aedes albopictus, the ideal Goldilocks temperature was roughly 79 degrees Fahrenheit. For Aedes aegypti, it was slightly higher, a balmy 84 degrees.

There is a built-in limit, says Mordecai: Too far past those Goldilocks temperatures and mosquitoes suffer and start to die. And a dead mosquito can't spread disease.

The researchers could track changes in temperature over time in tandem with changes in reported disease cases. And using climate models, they could tease out how much of the temperature rise in each location could be blamed on human-caused climate change — a technique called attribution. Then, using sophisticated statistical techniques borrowed from economics, they could link the human-driven temperature increases with increased caseloads.

Similar strategies are now commonly used to diagnose human-caused climate change's fingerprint on extreme weather like heat waves or hurricanes. But the new analysis is one of the first to explicitly link climate change to changes in infectious disease cases.

"Understanding how much of the increase in disease can be attributed to climate can give us more confidence in our predictions for how infections are going to respond to future climate changes," says Marta Shocket, a disease ecologist at Lancaster University in the U.K. "And this can help us do better long-term planning for how we allocate different public health resources."

Overall, the researchers found that temperature conditions generally favor the expansion of the disease, especially in areas like highland Mexico, Bolivia and Brazil. Hotter areas, like Thailand and Cambodia, have seen growth as well, but smaller marginal increases because temperatures were already near the mosquitoes' upper limits.

They could also look into the future to see where risks might emerge — and how many cases could be in store in an even hotter future. Many parts of South America, particularly those that are at the cooler end of the mosquitoes' preferred temperature range now, could see their caseloads double by the middle of the century if warming continues on its current trajectory. Only Cambodia was projected to see a drop in cases.

"A lot of regions that are more temperate will become more suitable — and what's scary is that it happens to overlap a lot with really densely populated cities," says Jamie Caldwell, an infectious disease researcher at Princeton University who was not involved in the study.

A health worker dispenses insecticide with fogging machines to kill mosquitoes spreading dengue fever ahead of the Day of the Dead celebrations in Merida, Mexico. 2024 broke records for the number of dengue fever cases reported worldwide.

Hugo Borges/AFP via Getty Images

The study did not include countries where dengue fever is still rare, a category which includes the U.S. But the number of cases within U.S. borders has also risen sharply in recent years, in hot, humid regions like Florida and southern Texas. But in 2023, several cases of locally acquired dengue fever were reported for the first time in Southern California. More were identified this year in Los Angeles County.

When dengue caseloads are high in the rest of the world, it increases the chances the disease can make its way into new areas, like the U.S., says Katharine Walter, an epidemiologist at the University of Utah.

"The world is more connected than ever before, and country borders are artificial," she says. "Unchecked viral transmission doesn't stay in one place."

Public health efforts still matter — a lot

A hotter planet contributes to the expansion of the disease — but it is far from the only reason, says Benny Rice, a disease ecologist at Princeton University. Dengue fever, like other diseases spread by "vectors" like mosquitoes or ticks, is controlled by a vast array of factors.

Urbanization — particularly in unplanned developments like those springing up on the outskirts of cities worldwide — often creates mosquito havens, leading to a higher likelihood of disease outbreaks. Global travel also allows the disease to spread quickly and easily between regions. Other weather factors, like the frequency and intensity of rainfall or extreme weather, also influence the dynamics of dengue outbreaks.

In some ways, all that complexity represents opportunity, says Rice. He points out that even if climate change influences 20% of dengue cases — or even more — that leaves 80% of cases that could be reined in. "The public health interventions that have existed for years are more important than ever," he says — from efforts like aggressive efforts to curb mosquito populations to developing strong local networks of medical care.

Nonetheless, the study shows that "the climate really gives context for where and when outbreaks could occur," Caldwell says.

The analysis suggests dengue cases will continue to skyrocket as Earth's climate continues to warm. By the middle of the century, the number of cases could rise by 60% as more parts of the world enter the mosquito-friendly temperature zone.

But Mordecai says that points to a clear solution: alongside the other public health measures, any success at slowing Earth's warming by reducing planet-warming emissions will lessen the risks.

In 2014, California became the first state to pass a plastic bag ban. It’s one of at least 12 states that now have some form of ban on single-use plastic bags.

But because of a loophole in its initial ban that allowed grocers to charge for thicker plastic bags, California still dumped 231,072 tons of plastic grocery and merchandise bags in landfills in 2021, according to the state’s recycling agency, CalRecycle. That was a sharp increase from the year the ban took effect — and nearly 100,000 more tons than in 2018.

California officials are saying that there's a perception that plastics — especially plastic bags — can be easily recycled. But they say that this is not the reality and that consumers have been deceived for decades.

“CalRecycle has not identified facilities that recycle plastic bags in the state of California,” the agency told NPR this week.

The state filed a suit on Sunday alleging that ExxonMobil promoted recycling while knowing that it was technically and economically challenging and wouldn't make much of a dent in the plastic waste problem.

Here’s a rundown of California’s new ban and similar measures:

Why did California’s initial bag ban backfire?

The state’s ban on thin single-use bags had a loophole that let grocers sell shoppers thicker plastic bags for a small fee: just 10 cents. In theory, the heavier bags were reusable. But in practice, they became a more substantial form of waste.

“A plastic bag has an average lifespan of 12 minutes and then it is discarded, afflicting our environment with toxic microplastics that fester in our oceans and landfills for up to 1,000 years,” Sen. Catherine Blakespear, an author of the new ban, said in a news release issued after Gov. Gavin Newsom signed the ban into law on Sunday.

The initial ban was also undermined by the COVID-19 pandemic. When it was still unknown how the coronavirus spread, shoppers were barred from bringing reusable bags into grocery stores out of fear that their bags might be contaminated.  

“California kind of took one for the team as the first to pass a statewide ban on plastic bags,” Melissa Valliant, communications director for the advocacy group Beyond Plastics, told NPR. “It ended up providing a lesson for other state and even local governments to learn from and to not allow loopholes like thicker plastic bags.”

What does the new California law do?

Starting on Jan. 1, 2026, customers at most grocery stores, convenience stores, and other retailers will have three main options: Pay at least 10 cents for a paper bag; use a reusable bag; or hand-carry their purchase.

“Stores may offer paper bags at the point-of-sale, and they can also sell the canvas-style reusable bags in other areas of the store,” Nate Rose of the California Grocers Association, which supports the new ban, told NPR.

“These are the bags many shoppers are already accustomed to bringing with them to carry their groceries,” Rose added.

And starting in 2028, stores’ paper bags will be required to be composed of at least 50% postconsumer recycled materials.

More than 70 organizations supported the legislation, member station LAist reports, saying it “would prevent plastic waste, which releases toxic chemicals into the air, water and soil.”

California's attorney general, Rob Bonta, has filed a lawsuit against ExxonMobil, alleging that the oil and gas corporation misled consumers by telling them that recycling was a viable solution for plastic waste. In 2021, some 231,072 tons of plastic grocery and merchandise bags went to landfills, according to the state’s recycling agency, CalRecycle.

Muhammad Owais Khan/Getty Images

What’s so bad about plastic bags?

Despite industry claims about their recyclability, the thin bags are notoriously difficult and expensive to process and recycle. Instead, they often wind up in landfills, where they will persist for centuries, or in incinerators.

For a sense of the scale of the problem, consider Philadelphia. An evaluation commissioned by the city said last year that in Philadelphia, “an estimated 1 billion single-use disposable plastic bags are used annually,” adding to waste, litter and emissions challenges.

Municipal systems, the evaluation stated, “are unable to recycle plastic bags and the soft material causes equipment jamming at recycling centers, leading to dangerous and costly repairs that account for 150 hours of lost staff time and $300,000 in city costs.”

In contrast, restrictions like bag bans “can be expected to eliminate almost 300 single-use plastic bags per person per year, on average,” according to an analysis by Environment America and the U.S. PIRG Education Fund that was published in January.

What does the plastic industry say?

Bag manufacturers are against bans on their products and they insist that the thin plastic film bag, made of polyethylene, makes more sense than the alternatives.

“A polyethylene bag is 100% recyclable and can be recycled into itself, is produced with low carbon emissions, and the PE is made domestically from natural gas,” a general manager of bag supplier Crown Poly said in a 2023 report prepared by Freedonia Custom Research on behalf of an industry group, the American Recyclable Plastic Bag Alliance.

“Conversely, PP [polypropylene] bags are produced overseas and imported, produce higher emissions than film bags, and are not recyclable. In fact, 99% of PP is virgin and does not contain post-consumer recycled material,” the report states.

Note: While single-use bags can technically be recycled, it’s not an easy or cost-effective process.

“To the extent they get recycled, a lot of polyethylene plastics get turned into low-grade materials. You can’t take a plastic bag and then make another plastic bag with the same properties out of it,” chemistry researcher John Hartwig of the University of California, Berkeley said in 2022, as he worked on ways to reuse the ubiquitous material. 

The American Recyclable Plastic Bag Alliance and another industry group, the Plastics Industry Association, did not respond to NPR’s request for comment on the new California ban before this story was published.

California will require shoppers to use paper bags or a reusable bag. In this photo from 2007, a woman loads plastic bags of groceries into her car at a Safeway store in San Francisco, before the city — and later, the state — adopted a ban on plastic checkout bags.

David Paul Morris/Getty Images/Getty Images North America

Should people just use paper bags?

When bans on single-use plastic bags haven’t also included a fee on paper bags, their use has soared. In Portland, Ore., for instance, paper bag use shot up by nearly 500% after the city enacted a ban (and before the state imposed its own ban with a fee for paper alternatives).

A similar dynamic has played out in Philadelphia, where the proportion of supermarket shoppers using at least one paper bag tripled after a plastic-bag ban took effect without a fee for paper. A recent bid to tack on a 15-cent fee for paper bags was axed by a pocket veto.

Paper bags are easier to recycle than plastic, and more degradable. But environmental advocates want retailers and shoppers to move away from single-use bags of any type. They argue that a few minutes of convenience isn’t enough to justify cumbersome networks of bag collection, processing and production needed to recycle single-use bags.

“The whole goal is to get people to switch from disposable options — especially plastic, but disposable options altogether — to reusable and refillable options,” Valliant said. “Because ultimately that is going to be the most sustainable and the best for both environment and human health.”

Which 12 states have banned plastic bags? 

In 2024, Colorado and Rhode Island enacted statewide bans on single-use plastic bags, joining 10 states that already had restrictions in place: California, Connecticut, Delaware, Hawaii, Maine, New Jersey, New York, Oregon, Vermont and Washington.

At their core, such bans are attempts to shift responsibility for plastic waste from consumers upstream — to retailers and, by extension, plastic producers.

The same week California’s new ban became law, the state opened another front in its battle with plastic waste by filing a lawsuit against oil and gas giant ExxonMobil, a leading producer of the polymers used to make single-use plastics.

“For decades, ExxonMobil has been deceiving the public to convince us that plastic recycling could solve the plastic waste and pollution crisis when they clearly knew this wasn’t possible,” California Attorney General Rob Bonta said.

Bonta accused ExxonMobil of profiting from “convincing consumers that they were responsible for the proliferation of plastic waste through their own personal habits, rather than through Mobil’s and Exxon’s efforts to produce an increasing number of plastic products designed for single-use.”

They are at an impasse over whether the treaty should reduce the total plastic on Earth and put global, legally binding controls on toxic chemicals used to make plastics.

The negotiations in Busan, South Korea, were supposed to be the fifth and final round to produce the first legally binding treaty on plastics pollution, including in the oceans, by the end of 2024. But with time running out early Monday, negotiators agreed to resume the talks next year. They don't yet have firm plans.

More than 100 countries want the treaty to limit production as well as tackle cleanup and recycling, and many have said that is essential to address chemicals of concern. But for some plastic-producing and oil and gas countries, that crosses a red line.

For any proposal to make it into the treaty, every nation must agree to it. Some countries sought to change the process so decisions could be made with a vote if consensus couldn't be reached and the process was paralyzed. India, Saudi Arabia, Iran, Kuwait and others opposed changing it, arguing consensus is vital to an inclusive, effective treaty.

On Sunday, the last scheduled day of talks, the treaty draft still had multiple options for several key sections. Some delegates and environmental organizations said it had become too watered down, including negotiators from Africa who said they would rather leave Busan without a treaty than with a weak one.

Every year, the world produces more than 400 million tons of new plastic. Plastic production could climb about 70% by 2040 without policy changes.

In Ghana, communities, bodies of water, drains and farmlands are choked with plastics, and dumping sites full of plastics are always on fire, said Sam Adu-Kumi, the country's lead negotiator.

"We want a treaty that will be able to solve it," he said in an interview. "Otherwise we will go without it and come and fight another time."

At Sunday night's meeting, Luis Vayas Valdivieso, the committee chair from Ecuador, said that while they made progress in Busan, their work is far from complete and they must be pragmatic. He said countries were the furthest apart on proposals about problematic plastics and chemicals of concern, plastic production and financing the treaty, as well as the treaty principles.

Valdivieso said the meeting should be suspended and resume at a later date. Many countries then reflected on what they must see in the treaty moving forward.

Chair of the International Negotiating Committee, Luis Vayas Valdivieso (right), speaks with Inger Andersen, executive director of UNEP, before the start of a plenary of the fifth session of the Intergovernmental Negotiating Committee on Plastic Pollution in Busan, South Korea, Sunday, Dec. 1, 2024.

Ahn Young-joon/AP

Rwanda's lead negotiator, Juliet Kabera, said she spoke on behalf of 85 countries in insisting that the treaty be ambitious throughout, fit for purpose and not built to fail, for the benefit of current and future generations. She asked everyone who supported the statement to "stand up for ambition." Country delegates and many in the audience stood, clapping.

Panama's delegation, which led an effort to include plastic production in the treaty, said they would return stronger, louder and more determined.

Saudi Arabia's negotiator said chemicals and plastic production are not within the scope of the treaty. Speaking on behalf of the Arab group, he said if the world addresses plastic pollution, there should be no problem producing plastic. Kuwait's negotiator echoed that, saying the objective is to end plastic pollution, not plastic itself, and stretching the mandate beyond its original intent erodes trust and goodwill.

In March 2022, 175 nations agreed to make the first legally binding treaty on plastics pollution, including in the oceans, by the end of 2024. The resolution states that nations will develop an international legally binding instrument on plastic pollution based on a comprehensive approach that addresses the full life cycle of plastic.

Stewart Harris, a spokesperson for the International Council of Chemical Associations, said it was an incredibly ambitious timeline. He said the ICCA is hopeful governments can reach an agreement with just a little more time.

Most of the negotiations in Busan took place behind closed doors. Environmental groups, Indigenous leaders, communities impacted by plastic pollution and scientists who traveled to Busan to help shape the treaty said it should've been transparent and they felt silenced.

"To a large degree, this is why the negotiation process is failing," said Bjorn Beeler, international coordinator for the International Pollutants Elimination Network. "Busan proved that the process is broken and just hobbling along."

South Korea's foreign affairs minister Cho Tae-yul said that though they didn't get a treaty in Busan as many had hoped, their efforts brought the world closer to a unified solution to ending global plastic pollution.

In recent years, "atmospheric river" has become used much more frequently in scientific papers and in media coverage. According to experts who study climate and weather, a couple reasons may explain why.

Technical weather terms in general are now more used in the news. Atmospheric rivers are a thriving area of research, more of which may be filtering into media coverage. And these storms are also expected to intensify and become more damaging as the climate warms – which means there's more attention on them.

What is an atmospheric river anyway?

Before we get into why we're hearing about them more, let's go over the basics of what an atmospheric river is.

These storms have always existed. They occur around the world, often on the west coasts of the mid-latitudes, where an ocean meets a landmass. They're long filaments of concentrated water vapor in the lower atmosphere occurring along with strong winds – and they're the primary way water is moved horizontally. In California, a normal winter might see five of these kinds of storms and as many as 20 could occur during wet winters. A typical one can be 300 miles wide, a mile deep and 1,000 miles long. When plotted on a map or looked down upon from a satellite in space they looked just like rivers.

For a long time, they were colloquially and scientifically referred to as things like the Pineapple Express or Rum Runner Express. Those turned out to be just a subset of atmospheric rivers however, ones that originated near Hawaii or in the Caribbean heading toward Europe. Not all ARs are particularly warm or begin in those locations.

"So the 'atmospheric river' term is the broader envelope," says Daniel Swain, climate scientist at the University of California.

The term was coined in a 1994 paper by two researchers at the Massachusetts Institute of Technology.

"And it turns out that they are very comparable to terrestrial rivers in terms of how much water is moving in them," Swain said. "In fact, sometimes they're significantly greater even than some of the flow of the largest terrestrial rivers on earth," including the Mississippi or Amazon River.

How we talk about the weather has changed

Swain believes that one reason people are suddenly hearing about atmospheric rivers more is because those who communicate about weather to the public have made a shift to using terms that the scientific community uses.

"I think a lot of it probably has to do with the media landscape and the popularization of certain technical weather terms," he said, pointing to "bomb cyclone" and "bombogenesis" as other examples. These are formal, quantitatively defined meteorological terms, "and everyone assumes that's just some invention of the social media hype era."

In fact, he says, these seem to date back to the 1940s during World War II when meteorologists were advising Allied forces in the North Atlantic Theater.

Atmospheric river, he says, is similar.

"Instead of just making something up out of the ether," Swain says, "there's been an interest in what are actually meaningful, technically correct scientific terms to describe various weather phenomena, which I'm not so sure is a bad thing."

Scientists have done a lot to understand atmospheric rivers better

In recent years, ARs have been a blooming area of research, some of which is filtering into media coverage.

Marty Ralph, director of the Center for Western Weather and Water Extremes at Scripps Institution of Oceanography, has been a pioneer in the field and is frequently cited in the press.

Researchers like Ralph have helped discover how important atmospheric rivers are, both for California but also for storms around the country and world. Back in 2004, the topic had fallen out of favor, says Ralph. But with new data collected by aircraft and satellites he showed researchers how to see the storms in a new way, allowing scientists to observe them from the inside and out.

"I sort of resurrected the topic after an early pullback," Ralph said.

This now-vibrant area of research has made some recent discoveries, says Ralph, including how to better predict their effects, how they impact both snowfall and snowmelt in the polar regions and links between AR intensity and climate change.

"Because a warmer atmosphere holds more water vapor and water vapor is the fuel in atmospheric rivers, ARs can carry more water vapor," Ralph says. "And there are studies now that show we can expect to see somewhat more extreme ARs and more common, in some cases, just because of that."

The weather news in California has flipped from being about drought to being about storms

What may increase the impression that atmospheric rivers are a new thing is that for a good part of the past decade, California was in serious drought and wasn't getting them. Then in early 2023, multiple AR storms followed one after another, resulting in flooding around California and 22 deaths.

"In both cases, it's a story about atmospheric rivers, in one case a deficit of atmospheric rivers, not enough of them, and the other case overabundance – too many atmospheric rivers all at once," said Swain. "California water lives and dies by this."

Atmospheric rivers are at fault in more than 80 percent of flooding across the West. On average these storms cause $1 billion in damage each year.

A look at Google Trends, reveals an early blip of interest in atmospheric rivers in early 2011, hardly anything during the drought years of 2012-2016, then more blips in 2017, 2019 and 2021 coinciding with West Coast storms and flooding. And finally large spikes in interest in 2023 and 2024. So far this fall has only brought one AR to California, but it is a record-breaking one.

A major development for the future of atmospheric river research, says Ralph, is the possibility of improving our forecasting up to two weeks before a storm.

Legislation introduced on Wednesday by Senators Alex Padilla (D-Calif.) and Lisa Murkowski (R-Alaska) seeks to secure funding to increase airborne reconnaissance – using planes to fly through the storms – to learn more about atmospheric rivers.

"The more we sample these storms, the more accurate the forecasts become," said Ralph.

Felt around the country

Lest you think these storms are purely a West Coast phenomenon, researchers are increasingly appreciating ARs role in fueling and directing nor'easters, strong storms that impact the East Coast.

"It's quite possible that AR recon in the Gulf of Mexico and off the East Coast will actually be able to improve the forecast scale of the track and intensity of nor'easters," Ralph said, "which people in the East know full well, is a very important detail in order to determine if the big cities are impacted."

NPR audiences first heard about atmospheric rivers in 2013, when Jon Hamilton offered "Tips for Surviving a Mega Disaster."

The world produces about 400 million metric tons of plastic waste every year, according to the United Nations Environment Programme. That's about the sum total of how much every human on the planet weighs. Most plastic ends up in places like oceans, shorelines and landfills, where it breaks down into tiny pieces called microplastics that have been found in every corner of the environment and inside human bodies. The problem is getting worse, with plastic pollution expected to soar in the coming decades. So in 2022, U.N. member states said they'd write a legally binding agreement to keep plastic waste out of the environment.

But for months, the talks have been deadlocked. Plastic is made from fossil fuels. Environmental groups, scientists and human rights activists say the oil and gas industry, along with major producers like Russia and Saudi Arabia, have delayed progress and blocked measures that could hurt demand for their products.

However, some observers of the negotiations now see a path for countries to broker a deal. That's due in part to signals from the Biden administration in recent months that the U.S. might support more aggressive actions to reduce plastic pollution.

"We have all the right conditions at play," says Erin Simon, head of plastic waste and business at the World Wildlife Fund. "Can the chair [of the U.N. negotiating committee] finish the job? And will these countries stand up and speak for what they have been saying they are committed to doing when the time is right? Will they drown out the few and speak for the majority?"

A volunteer collects plastic waste that washed up on the shores and mangroves in the Philippines.

Ezra Acayan/Getty Images

Talks open in the shadow of a U.S. election

The final round of talks is getting underway weeks after U.S. voters reelected Donald Trump as president. For years, Trump has cast doubt on the scientific consensus that the Earth is getting hotter mainly because of human-caused greenhouse gas emissions, which come primarily from burning fossil fuels. And Trump has promised to pursue policies in his second term that support the United States' oil and gas industry.

Trump's transition team did not respond to messages seeking comment about the incoming administration's stance on plastic pollution.

Simon says U.S. politics could have some impact on the plastic negotiations, but she says the goal isn't to set U.S. policy or design a treaty that can be ratified immediately by the United States.

"The target is, how do we mobilize globally," Simon says. "And how do we make sure that no matter what [happens] in the U.S., we're taking action?"

Even before Trump's reelection, observers of the negotiations were reluctant to count on U.S. leadership. The Biden administration faced sharp criticism for backing policies that aligned with the interests of the plastics industry. And the U.S. historically has been a laggard in global environmental initiatives, says Carroll Muffett, executive director of the Foundation for International Law for the Environment.

There's a pattern of the U.S. "advocating for very weak agreements that it then ends up not participating in anyway," Muffett said ahead of a prior round of plastic negotiations in Canada this spring.

A sculpture titled Giant Plastic Tap by Canadian artist Benjamin Von Wong is displayed outside the fourth session of the U.N. Intergovernmental Negotiating Committee on Plastic Pollution in Ottawa, Canada, in April.

Dave Chan/AFP via Getty Images

Scientists say the solutions to plastic waste are clear

A major sticking point in these negotiations has been a measure to limit the production of new plastic. Scientists and environmental advocates, along with attorneys general from New York, California and eight other states, say that the world manufactures too much plastic to manage effectively and that countries need to cap production to have any hope of making a dent in pollution.

Plastic-makers see that sort of regulation as a threat to their business. The industry wants negotiators to focus on creating what's called a circular economy, where plastic is recycled and reused to prevent waste.

But investigations, including by NPR, have found that the plastics industry promoted recycling for decades even though officials long knew that it probably wouldn't work on a large scale. Former industry officials have said the goal was to avoid regulation and ensure demand for plastics kept growing.

Current officials have said those investigations don't accurately portray today's industry.

Matt Seaholm, chief executive of the Plastics Industry Association, a trade group, said in a statement that his organization supports an "ambitious" treaty but warned against policies like production caps that he said would hurt plastic manufacturers "without reaching our shared sustainability goals."

Countries are also debating whether to regulate the chemicals that go into plastics. A study this year found that plastics contain more than 4,200 hazardous chemicals, the vast majority of which aren't regulated globally, according to the researchers. The plastics industry argues that chemicals should be regulated by national governments, not by a global treaty on plastic pollution. But scientists and environmentalists calling for global chemical regulations note that plastic waste — as well as the chemicals the plastic is made from — doesn't stay in the country where it's produced. It travels around the world in rivers and oceans.

Other issues under consideration include setting design standards to ensure plastic is safe to reuse and recycle, requiring companies to use some recycled material in their plastic products and raising money to help pay for waste management infrastructure, especially in developing countries.

"From the vantage point of science, it's very clear what actions we need. So, there's no ambiguity there. It's just a matter of political will," says Douglas McCauley, a professor of environmental science at the University of California, Santa Barbara, who has studied ways to cut plastic pollution.

And McCauley says world leaders have plenty of reasons to act. "If you care about fighting cancer, well, there's a win here. If you care about environmental justice, there's a win here. If you care about the environment — oceans, rivers, all the rest — there's a win. If you care about climate change, there's a win," McCauley says.

A spokesperson for the White House Council on Environmental Quality said in a statement that the U.S. supports measures that address plastic supplies and the chemicals the industry uses. "Global plastic production is projected to triple by 2060, overwhelming solid waste management systems and contributing to pollution," the statement said. "An outsized proportion of that increase will be in the growth of single-use plastic products that will ultimately lead to more plastic pollution."

People look for reusable material at a garbage dump filled with plastic and other waste on the outskirts of Jammu, India.

Channi Anand/AP

Time is of the essence

Observers of the negotiations say countries could produce a strong treaty in South Korea even if they leave some details to be worked out later.

"You can't get everything concluded in Busan," says Magnus Løvold, a project manager at the Norwegian Academy of International Law. "But you can set a starting point that is credible for [the] governance of plastics internationally" in the coming years.

But time appears to be running short to lay that groundwork. When countries agreed to write a treaty to end plastic pollution, they set a goal to finish this year. Negotiators often extend talks when they run into gridlock. However, McCauley says participants in these deliberations seem committed to sticking to the original timeline.

For developing nations especially, letting the talks drag out could sink their efforts to get a strong treaty, Simon says. The negotiations are scheduled to conclude Dec. 1.

"Those countries will run out of resources to be a major player in negotiations," Simon says. "The political pressure, the public pressure will wane as other things come into the picture."

If you ask Tim O'Connor, executive director of the National Christmas Tree Association, the answer is obvious.

"I think it's just a no-brainer that real Christmas trees are far superior for the environment," he said. "Let's just start with a product of nature versus a product that's made from oil."

Of course, O'Connor's organization represents Christmas tree farmers. Here's what studies and environmentalists say.

The studies

The most recent U.S. analysis of the issue is from 2018, when a life cycle assessment — measuring the environmental impact of real and fake trees over the course of production to disposal — was published. (It's worth noting that the study was done by a consulting firm contracted by the American Christmas Tree Association, which represents the artificial-tree industry.)

The analysis took into account things like the netting around real Christmas trees and the water used to keep them alive in homes, versus the plastic packaging tape used on fake-tree boxes and transportation from manufacturers in China.

It concluded that artificial trees have a more favorable effect on the environment if reused for at least five years.

It's worth noting, though, that with all these variables, the study says that transportation accounts for around 15% of total global warming potential for artificial Christmas trees and 10% to 12% for real ones. So if that tree farm or big-box store is a long drive away, it can really sway things.

"Neither a farm-grown tree or a faux tree has a superlarge environmental impact compared to some daily activities like commuting a long way in a gas-powered car," said Mac Harman, the CEO of Balsam Hill, which makes high-end fake trees and offers an eco-friendly line of trees made from recycled plastics and plant-based plastic. "One long commute could be about the impact of having a Christmas tree for a year."

Environmentalists, meanwhile, suggest studies shouldn't be the only evidence consumers take into account.

"Studies can really vary on anything depending on who's funding the study, what parameters they're looking at, which elements are the most important, or are they just looking at carbon impacts? Are they looking at other resource impacts? Are they considering extraction? Are they considering disposal?" said Darby Hoover of the Natural Resources Defense Council.

A man and child look at artificial Christmas trees on display at a Home Depot in Miami in 2021.

Joe Raedle/Getty Images

An environmentalist's take

Several environmental groups have waded into the debate, and for many of them, real trees are the winner.

"For me, it's not just carbon," said Hoover. "One of the things about the artificial trees is that they're made of plastic almost entirely. And the by-far-most-common polymer used to make artificial trees is PVC, polyvinyl chloride, which is a particularly toxic form of plastic that's toxic in production, use and disposal."

It's worth noting the endgame for both options: If real trees end up in a landfill and don't break down, they're still storing all the carbon they absorbed in life. And if they're mulched, they're being reused for greener purposes. Most artificial trees aren't recyclable.

"If [people] want to do what's better for the environment, if they want to support a family farmer, if they want to have the kind of Christmas experience for their family that is authentic, that includes something from nature rather than something from plastic, it's a pretty simple decision to have a real Christmas tree," O'Connor of the real-Christmas-tree association said.

How to be tree-mendously green for Christmas

Want to take it a step further? Let's go back to the tree's roots — as in letting the tree keep its actual roots.

The official White House Christmas tree, a 20-foot Fraser fir, is seen at Cartner's Christmas Tree Farm in Newland, N.C., on Nov. 13.

Erik Verduzco/AP

"I think the best option is using a plant that's already in your life or that you want to purchase and have stay in your life," said Hoover. "So rather than buying a plant that's going to be cut down, why not repurpose a tree that's already on your property or a really fancy potted plant that's already in your home?"

And if your wilted snake plant isn't Christmassy enough for you, there's another option. There are companies that allow you to rent a live Christmas tree that returns to the nursery when the holidays are over.

And if you already have a fake tree, keep using it. Harman of Balsam Hill says he knows people who still have trees from his company's early days nearly two decades ago.

"It doesn't make business any easier for us selling more trees when they last so long, but it's certainly good for the environment," he said.

After years of lobbying by island nations who fear they could simply disappear under rising sea waters, the U.N. General Assembly asked the International Court of Justice last year for an opinion on "the obligations of States in respect of climate change."

"We want the court to confirm that the conduct that has wrecked the climate is unlawful," Margaretha Wewerinke-Singh, who is leading the legal team for the Pacific island nation of Vanuatu, told The Associated Press.

In the decade up to 2023, sea levels have risen by a global average of around 4.3 centimeters (1.7 inches), with parts of the Pacific rising higher still. The world has also warmed 1.3 degrees Celsius (2.3 Fahrenheit) since pre-industrial times because of the burning of fossil fuels.

Vanuatu is one of a group of small states pushing for international legal intervention in the climate crisis.

"We live on the front lines of climate change impact. We are witnesses to the destruction of our lands, our livelihoods, our culture and our human rights," Vanuatu's climate change envoy Ralph Regenvanu told reporters ahead of the hearing.

Any decision by the court would be non-binding advice and unable to directly force wealthy nations into action to help struggling countries. Yet it would be more than just a powerful symbol since it could serve as the basis for other legal actions, including domestic lawsuits.

On Sunday, ahead of the hearing, advocacy groups will bring together environmental organizations from around the world. Pacific Islands Students Fighting Climate Change — who first developed the idea of requesting an advisory opinion — together with World Youth for Climate Justice plan an afternoon of speeches, music and discussions.

From Monday, the Hague-based court will hear from 99 countries and more than a dozen intergovernmental organizations over two weeks. It's the largest lineup in the institution's nearly 80-year history.

Vanuatu Prime Minister Charlot Salwai Tabimasmas addresses the 79th session of the United Nations General Assembly in September.

Richard Drew/AP

Last month at the United Nations' annual climate meeting, countries cobbled together an agreement on how rich countries can support poor countries in the face of climate disasters. Wealthy countries have agreed to pool together at least $300 billion a year by 2035 but the total is short of the $1.3 trillion that experts, and threatened nations, said is needed.

"For our generation and for the Pacific Islands, the climate crisis is an existential threat. It is a matter of survival, and the world's biggest economies are not taking this crisis seriously. We need the ICJ to protect the rights of people at the front lines," Vishal Prasad, of Pacific Islands Students Fighting Climate Change, told reporters in a briefing.

Fifteen judges from around the world will seek to answer two questions: What are countries obliged to do under international law to protect the climate and environment from human-caused greenhouse gas emissions? And what are the legal consequences for governments where their acts, or lack of action, have significantly harmed the climate and environment?

The second question makes particular reference to "small island developing States" likely to be hardest hit by climate change and to "members of "the present and future generations affected by the adverse effects of climate change."

The judges were even briefed on the science behind rising global temperatures by the U.N.'s climate change body, the Intergovernmental Panel on Climate Change, ahead of the hearings.

The case at the ICJ follows a number of rulings around the world ordering governments to do more to reduce greenhouse gas emissions.

In May, a U.N. tribunal on maritime law said that carbon emissions qualify as marine pollution and countries must take steps to adapt to and mitigate their adverse effects.

That ruling came a month after Europe's highest human rights court said that countries must better protect their people from the consequences of climate change, in a landmark judgment that could have implications across the continent.

The ICJ's host country of The Netherlands made history when a court ruled in 2015 that protection from the potentially devastating effects of climate change is a human right and that the government has a duty to protect its citizens. The judgment was upheld in 2019 by the Dutch Supreme Court.

As a subsistence farmer, Bingala didn't have the resources to start over. But then he got a payment of about $750, which he used to build his family a new house.

The payment is one of the first examples of "loss and damage" compensation, a new kind of funding specifically for climate change-related disasters. Low-income countries are bearing the brunt of more intense storms and droughts but have done little to produce the pollution that's heating up the planet. So last year, wealthier countries agreed to create a fund specifically to pay for the damages from climate change.

So far, about $720 million has been pledged from countries, like the European Union, U.S. and United Arab Emirates. But climate experts warn that with hurricanes and floods only getting worse, that amount will fall far short.

At the COP29 climate summit underway in Baku, Azerbaijan, countries are negotiating how much is owed to developing nations, as part of a larger "climate finance" package that includes loans and investments.

"We just hope that the global north and the nations whose economy is fueled by the emissions — they come to the plate and take up their responsibility to look at what they're causing us," says Philip Davis, prime minister of the Commonwealth of the Bahamas.

Finding a way to start over

The havoc from Cyclone Freddy was widespread across several countries, displacing 650,000 people from their homes in Malawi alone. The country received six months of rain in just six days.

After their house collapsed in the floodwaters, Bingala and his family took refuge on higher ground, but the situation quickly deteriorated. They started running out of food.

Christopher Bingala, a farmer in Malawi, stands outside his new home. After losing his house in Cyclone Freddy, he received a payment from a new fund for the damages from climate-related disasters.

Henderson Mhone

"We got to a point where we would eat meat from animals that had died from the cyclone because we lacked food," Bingala says. "This was a very difficult moment in my life."

Along with thousands of others, he and his family were relocated to temporary camps. But as a small-scale farmer and fisherman, Bingala had no safety net to fall back on. Then he received the cash payment, which allowed him to move to a new village and build a better house. There are still challenges — Bingala is still trying to get his kids back in school and he's hoping to get a few livestock again. But he's glad his family is living in a less flood-prone region.

"They are better off here because they are not in danger of the water challenges we had back in Makhanga," Bingala says. "This is a dry and upper land, so my children are ok and they're happy. They're living a happy life."

Piloting a system to pay damages

The payment Bingala received came from the government of Scotland, the first country to dedicate funding specifically for loss and damage. The funds have gone to several countries so far. In Malawi, they were given out by GiveDirectly, a nonprofit that specializes in providing cash grants to those in need with no strings attached.

About 2,700 families got payments of around $750, which can be equivalent to two years of income in Malawi. Many used the money to rebuild homes, while others invested in seeds, fertilizers and livestock, or putting their kids back in school.

"Low-income households in low-income countries have far less protections from extreme events," says Yolande Wright, vice president of partnerships at GiveDirectly. "They may not have any sort of insurance. There may not be any insurance products available, even if they wanted to buy them."

The program in Malawi is a pilot, in a sense, for a larger system to pay for loss and damage. Last year, countries agreed to create the fund as a way to compensate lower-income countries, which have low greenhouse gas emissions overall. Almost half of all emissions since the Industrial Revolution have come from the U.S. and Europe.

"The very poor, low-income households in Malawi have contributed the least to the climate problem," Wright says. "Many of them are not connected to electricity. They don't own a car or even a motor bike."

A ballooning need for loss and damage funding

Increasingly severe hurricanes, storms and droughts pose a massive financial burden on developing countries, especially those already in debt. In the Bahamas, Prime Minister Davis says his country's national debt went up after Hurricane Dorian hit in 2019.

"For me to recover and rebuild, I have to borrow," Davis says. "Forty percent of my national debt could be directly attributed to the consequences of climate change."

So far, the majority of $720 million pledged for loss and damage has yet to start flowing. At the COP29 summit, countries finalized the paperwork to create the fund, which will be housed at the World Bank. The fund's guidelines have yet to be set up, like determining which countries will receive funding and for what kinds of damages.

Many low-income countries have argued the funding should go to more than just disaster recovery. Some could be used to relocate villages in the path of sea level rise, or to compensate countries for the loss of important cultural sites or ecological resources, like coral reefs.

The need for loss and damage funding is only expected to balloon as disasters get more extreme. One recent study found it will reach $250 billion per year by 2030. Davis says he hopes richer countries will contribute more in "enlightened self-interest," since many humanitarian crises do not stay confined to country borders.

"If they do nothing, they will be the worst for it," Davis says. "When my islands are swallowed up by the sea, then what do my people do? They'll either become climate refugees or they'll be doomed to a watery grave."