Rebecca Hersher

The Environmental Protection Agency is cracking down on a powerful class of greenhouse gases that are used in refrigerators, air conditioners and building insulation. On Monday, the agency announced a new regulation that would dramatically decrease production and use of hydrofluorocarbons, or HFCs, over the next 15 years.

It's the first concrete regulatory step the Biden administration has taken to tackle planet-warming emissions since the president announced ambitious goals 10 days ago to cut U.S. emissions by half in the next decade.

Updated April 22, 2021 at 6:14 AM ET

On Thursday, the White House kicked off a two-day summit on climate change where leaders from 40 countries are discussing plans to cut greenhouse gas emissions and ultimately reverse global warming.

The summit highlights the United States' return to the Paris climate agreement, and it is the Biden administration's first major opportunity to reestablish the country as a trustworthy player in international climate diplomacy.

The National Oceanic and Atmospheric Administration upgraded the computer model that forecasters use to predict the weather one to two weeks in the future, called the Global Forecast System. The new model is better at predicting where hurricanes will form and how intense they will be as well as where and when snowstorms and rainstorms will occur, and how much precipitation will fall.

"This is going to have a fundamental impact on the forecasts that are provided day to day," says Louis Uccellini, director of the National Weather Service.

Humans have changed the Earth in such profound ways that scientists say we have entered a new geological period: the Anthropocene Epoch.

But when did the new epoch officially begin? And how, exactly, should it be defined?

Those are the questions that geologists are pursuing with increasing urgency at sites around the world. Teams are studying 11 locations on five continents, looking for a place where rock, mud or ice perfectly capture the global impact of humans.

Copyright 2021 NPR. To see more, visit https://www.npr.org.

AILSA CHANG, HOST:

Federal scientists have confirmed that 2020 basically tied with 2016 for the hottest year recorded since 1880. The Earth is about 2 degrees Fahrenheit warmer today than it was in the mid-20th century. Scientists warn that humans must keep global temperatures from rising more than about 3 degrees Fahrenheit in order to avoid the most catastrophic effects of climate change.

Devon Hall has lived most of his nearly seven decades in Duplin County, N.C. The land is flat and green there in the southeastern part of the state, about an hour's drive from the coast. It's lovely unless you live downwind of one of the county's many industrial hog farms.

"It can get really bad," says Hall, the co-founder of the Rural Empowerment Association for Community Help in Duplin County.

President-elect Joe Biden will name Michael Regan, North Carolina's environment secretary and a former EPA official, to lead the Environmental Protection Agency, according to a source familiar with the decision who spoke about private conversations on the basis of anonymity.

With just a few weeks left, 2020 is in a dead-heat tie for the hottest year on record. But whether it claims the top spot misses the point, climate scientists say. There is no shortage of disquieting statistics about what is happening to the Earth.

A satellite scheduled to launch from California later this month will measure sea level rise and provide other crucial data to scientists who study how global warming is affecting the Earth's oceans.

The United States will formally leave the Paris Agreement on Wednesday, no matter who wins the election. Of the nearly 200 nations that signed the agreement, the U.S. is the only one to walk away from its promises to reduce greenhouse gas emissions.

President Trump originally announced his intention to withdraw from the landmark agreement in 2017 and formally notified the United Nations last year. A mandatory yearlong waiting period ends on Wednesday, a coincidence that nonetheless highlights the Trump administration's commitment to derailing efforts that address climate change.

Each family had their reasons for ending up in harm's way.

For the Harts, it was the chance to have a large backyard in a quiet part of Ashland, Ore. The porch of the Baltimore house was perfect for Scott Harris' barbecue equipment. Kevin Boudreaux had grown up on the bayou and wanted to settle near his childhood home in Cameron, La.

A 25-year-old was infected twice with the coronavirus earlier this year, scientists in Nevada have confirmed. It is the first confirmed case of so-called reinfection with the virus in the U.S. and the fifth confirmed reinfection case worldwide.

The cases underscore the importance of social distancing and wearing masks even if you were previously infected with the virus, and they raise questions about how the human immune system reacts to the virus.

Updated Friday, 4:30 p.m. ET

Millions of people rely on real estate websites when they're hoping to buy or rent a home. Major sites such as Zillow, Redfin, Trulia and Realtor.com feature kitchens, bathrooms, mortgage estimates and even school ratings. But those sites don't show buyers whether the house is likely to flood while they're living there.

Scientists are trying to understand how much plastic humans are pumping into the ocean and how long it sticks around. A study published this week says it may be much more than earlier estimates.

By some measures, the plastic trash that's floating on the surface of the water only accounts for about 1% of the plastic pollution that humans generate.

Local officials and public health experts warn that domestic violence is spiking in Australia as the country deals with the aftermath of catastrophic fires paired with the global pandemic.

The fires killed at least 35 people and destroyed nearly 2,000 houses in the southeastern part of the country in 2019 and early 2020, leaving thousands of Australians jobless and still in temporary housing as the coronavirus pandemic swept through with its widespread lockdowns, illness and economic pain.

President Trump's nominee to lead the Consumer Product Safety Commission is Nancy Beck, a toxicologist who currently leads chemical and pesticide regulation at the Environmental Protection Agency.

The CPSC is the top federal consumer watchdog in the country. Its five-member board, which Beck will lead for seven years if she is confirmed, is responsible for reviewing safety information and collecting injury reports for more than 15,000 types of products, from baby toys to sports equipment to home appliances.

Some of the country's most polluting industries have flooded state regulators with requests to ease environmental regulations, according to an NPR review of hundreds of state environmental records.

Companies across the country say the pandemic is interfering with their ability to comply with laws that protect the public from pollution.

Thousands of people in Baltimore have joined multiple marches over the past week, mourning the violent death of George Floyd in Minneapolis and calling for less funding for the Baltimore Police Department and more money for education, health and local groups in predominantly African American neighborhoods in the city.

Don't see the graphic above? Click here.

With traffic dramatically down in recent months, the United States is in the middle of an accidental experiment showing what happens to air pollution when millions of people stop driving.

Unprecedented job losses and furloughs have pushed millions of Americans to the brink of eviction during the coronavirus pandemic, but the Federal Emergency Management Agency and the White House have failed to fund a legal assistance program that is routinely available to disaster survivors.

The number of patients being treated at overflow hospitals in New York City has more than doubled in the last two days, the Department of Defense says.

On Thursday, military doctors and nurses were treating 189 patients at the overflow hospital at the Javits Convention Center in Manhattan, including 15 patients who are being treated in an intensive care unit inside the facility. The Navy hospital ship USNS Comfort currently has 53 patients, including 10 who are critically ill with COVID-19.

On Tuesday, the two facilities had fewer than 100 patients combined.

The USNS Comfort hospital ship and an emergency hospital at the Javits Center are meant to be relief valves for hospitals in New York City, where more than 14,000 people have been hospitalized for COVID-19. But the facilities have been largely empty, leading officials to try to streamline their operations.

Now, New York Gov. Andrew Cuomo is hoping the Comfort can join the Javits Center on the front line of the fight against the coronavirus.

Medical rationing is not something Americans are accustomed to, but COVID-19 may soon change that.

The specter of rationing is most imminent in New York City, where the virus is spreading rapidly and overwhelming hospitals with patients.

According to New York Gov. Andrew Cuomo, the state has 2,200 ventilators in its state stockpile. Current COVID-19 case projections suggest the state may not have enough of the machines, which help critically ill people breathe, as soon as next week.

Some New York City hospitals are still unable to perform reliable on-site coronavirus testing for patients and staff who show symptoms of COVID-19 and must instead wait days for results from outside laboratories, even as the city's hospital beds fill up with seriously ill people.

New York City hospitals are struggling to make sure they have enough staff, beds and protective equipment to treat a relentless and growing stream of COVID-19 patients. Providing effective, efficient care to people who are seriously ill requires hospitals to rapidly test people who appear to have the viral disease.

But even with New York's statewide effort to procure and distribute coronavirus testing supplies to hospitals, some medical centers say they still don't have what they need to test patients on-site. That includes one major hospital in Brooklyn.

Copyright 2020 NPR. To see more, visit https://www.npr.org.

Spring begins today in America. Good.

Perhaps you are mildly surprised to learn that March 19 is the first day of spring. Perhaps you learned as a child that the spring equinox — when day and night are roughly the same length — occurs on either March 20 or March 21.

First came the fires, denuding millions of acres of forest in eastern Australia. Now comes the rain, more than 12 inches in just 48 hours over this past weekend in some areas of New South Wales.

That sequence, severe bushfires followed by torrential rain, is bringing a third cataclysm — landslides and large-scale erosion.

Greenhouse gas emissions have risen steadily for the past decade despite the current and future threat posed by climate change, according to a new United Nations report.

The annual report compares how clean the world's economies are to how clean they need to be to avoid the most catastrophic effects of climate change — a disparity known as the "emissions gap."

Pages