PBS News Hour - Science

After a barrage of severe winter storms, 12 of California's 17 major reservoirs have been replenished -- a silver lining for a state suffering from brutal drought. But officials also warn that when the enormous snowpack atop the Sierra Nevada starts to melt, the runoff could cause a new threat to those below. Los Angeles Times reporter Hayley Smith joins William Brangham to discuss. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders

Over the past few months, artificial intelligence has managed to create award-winning art, pass the bar exam and even diagnose illnesses better than some doctors. But as AI grows more sophisticated and popular, the voices warning against the potential dangers are growing louder. Geoff Bennett discussed the concerns with Seth Dorbin of the Responsible AI Institute. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders

When you think of fresh produce and fields of grain, the Arctic may not spring to mind. But just 800 miles from the North Pole, the Global Seed Vault holds emergency stockpiles of most of the world's crops. It provides scientists with the tools they need to breed plants able to cope with a changing world. Special correspondent John Bevir visited the vault to learn more about the future of food. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders

A massive line of severe weather wreaked havoc from the Deep South to the Great Lakes. An estimated 85 million people were in the path of the storms, and at least 21 people were killed. We hear from residents affected by the tornadoes, and John Yang speaks with atmospheric scientist Walker Ashley for more on the storms. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders

A class of toxic chemicals known as PFAS has made its way into food, soil, water and even most people's blood in America. In March, the EPA proposed the first regulatory standard limiting the quantity of PFAS in drinking water. Erin Bell, an environmental epidemiologist at the State University of New York at Albany, joins Ali Rogin to discuss these "forever chemicals" and our exposure to them. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders

For fossil hunters, the thrill is often in the hunt. For 9-year-old Molly Sampson, her prehistoric shark tooth discovery along a Maryland beach is considered the find of a lifetime. And the dinosaur footprint English archaeologist Marie Woods spotted has revealed a new dinosaur behavior. Ali Rogin details these recent fossil finds that are helping advance scientific knowledge. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders

Scientists warned that human-induced climate change is warming the planet to the point where it is causing irreversible damage in some parts of the world. The report was released by the United Nations Intergovernmental Panel on Climate Change. Climate Scientist Katharine Hayhoe of The Nature Conservancy joined Amna Nawaz to look at what can be done to change the direction the planet is headed. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders

The Great Atlantic Sargassum Belt, a 5,000-mile-long belt of seaweed weighing more than 11 million tons, is threatening to wreak havoc in the coastal waters and beaches of the Atlantic Ocean. It's so big that it can be seen from space, spanning the tropical Atlantic from West Africa to the Caribbean. Oceanographer Ajit Subramaniam joins John Yang to discuss. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders

This Women's History Month, we're highlighting stories of women whose contributions have often been overlooked. Tonight, we look at the career of Chien-Shiung Wu, a 20th-century physicist who made indelible changes to her field. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders

U.S. airports have seen an uptick in near-collisions involving commercial planes. The problem prompted the FAA to call for a safety summit, launching a review of standards and procedures to prevent catastrophe. Geoff Bennett reports on the close calls and discusses the possible factors with aviation correspondent Miles O'Brien. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders