Christopher Joyce

The U.S. used to send a lot of its plastic waste to China to get recycled. But last year, China put the kibosh on imports of the world's waste. The policy, called National Sword, freaked out people in the U.S. — a huge market for plastic waste had just dried up.

Where was it all going to go now?

The avalanche of plastic waste that's rolling over land and sea has inspired numerous potential solutions. Some involve inventing our way out of the mess by creating new kinds of natural materials that will harmlessly degrade if they're thrown away.

Others say it might be quicker to change people's throwaway behavior instead.

Plastic waste gets a lot of attention when photos of dead whales with stomachs full of plastic bags hit the news. Pieces of plastic also litter cities, and tiny plastic particles are even floating in the air.

Largely overlooked is how making plastic in the first place affects the environment, especially global warming. Plastic actually has a big carbon footprint, but so do many of the alternatives to plastic. And that's what makes replacing plastic a problem without a clear solution.

If civilizations are remembered for what they leave behind, our time might be labeled the Plastic Age. Plastic can endure for centuries. It's everywhere, even in our clothes, from polyester leisure suits to fleece jackets.

A Silicon Valley startup is trying to get the plastic out of clothing and put something else in: biopolymers.

The largest habitat for life on Earth is the deep ocean. It's home to everything from jellyfish to giant bluefin tuna. But the deep ocean is being invaded by tiny pieces of plastic — plastic that people thought was mostly floating at the surface, and in amounts they never imagined.

When a marine biologist from Australia traveled to a remote string of islands in the Indian Ocean to see how much plastic waste had washed up on the beaches, here's just part of what she found: "373,000 toothbrushes and around 975,000 shoes, largely flip-flops," says Jennifer Lavers of the University of Tasmania in Australia.

And that's only what was on the surface.

The jawbone of a little-known form of ancient human has been discovered in western China. Scientists say these people lived as long as 150,000 years ago, and they were part of a group called Denisovans.

The Denisovans are a mystery. Up until now, their only remains — a few bone fragments and teeth — came from a cave called Denisova in Siberia.

Surprisingly high amounts of microplastic are raining down on a remote and seemingly pristine part of France's Pyrenees mountains, according to scientists who say such particles could potentially be floating everywhere.

An unusual species of human apparently lived on the island of Luzon in the Philippines as recently as 50,000 years ago. Based on teeth and bones found there, scientists suspect that these early humans probably stood less than 4 feet tall and had several apelike features. Yet, the researchers say, the bones are distinctly human — from a previously undiscovered species.

The Galapagos Islands are like a biological ark in the eastern Pacific Ocean. Giant tortoises live there, and swimming iguanas, and numerous species found nowhere else. It's one of the world's most protected places.

But scientists have discovered that dozens of exotic species have invaded the Galapagos — underwater.

Plastic garbage from Trader Joe's and an AARP card are peeking out of hillocks of plastic trash piling up in Indonesia.

It's a sign of a new global quandary: What should wealthy countries do with their plastic waste now that China no longer is buying it?

For years, America sold millions of tons of used yogurt cups, juice containers, shampoo bottles and other kinds of plastic trash to China to be recycled into new products.

And it wasn't just the U.S. Some 70 percent of the world's plastic waste went to China – about 7 million tons a year.

Scientists say they've found a mysterious type of killer whale that they've been searching for for years. It lives in parts of the ocean near Antarctica — and it could be the largest animal to have remained unidentified by biologists.

In January, we published a special report called "A New Weapon In The War Against Plastic Waste." It profiled Froilan Grate, a Filipino environmental activist, and his efforts to fight the non-recyclable plastic waste that is clogging miles and miles of coastline in the Philippines.

A diver in California has stumbled on an unexpected source of plastic waste in the ocean: golf balls.

As the balls degrade, they can emit toxic chemicals. And there appear to be lots of them in certain places underwater — right next to coastal golf courses.

Try this: Write a list of every piece of plastic you touch in a day.

I did it. I stopped counting at 56 items.

2018 was a hot year — in fact, the fourth warmest on record. The only years that were, on average, warmer were the past three, according to the World Meteorological Organization.

It has been warming for decades now. But 2018 brought several major new and markedly more precise reports from scientists about what climate change is doing to the weather and how dire they expect the consequences to be.

That didn't stop President Trump and others from continuing to question the evidence.

As climate negotiators from around the world meet in Poland this week and next to figure out how to keep greenhouse gases out of the atmosphere, they are hearing some discouraging news: Emissions of the biggest pollutant, carbon dioxide, are going up.

For three years — 2014 through 2016 — the amount of atmospheric CO2 had leveled off. But it started to climb again in 2017, and is still rising.

"Last year, we thought, was a blip — but it isn't," says Rob Jackson, a climate scientist at Stanford University in California.

The Trump administration released a major climate assessment on Black Friday, the culmination of years of research by the country's top climate scientists. It's well over 1,000 pages and touches on a daunting range of topics.

When the South Atlantic Ocean was young, sea monsters ruled it.

Some of their bones have turned up along the coast of West Africa and are going on exhibit Friday at the Smithsonian Institution in Washington, D.C. They tell a story of the bloody birth of an ocean.

The fossils of giant swimming reptiles called mosasaurs have been found in the rocky cliffs of Angola, overlooking the Atlantic. It's not a country known for fossils. Few scientists have looked there — half a century of civil war made it too dangerous. But geologically, Angola is special.

Some of the world's top climate scientists have concluded that global warming is likely to reach dangerous levels unless new technologies are developed to remove greenhouse gases from the atmosphere.

The United Nations' Intergovernmental Panel on Climate Change (IPCC) says pledges from the world's governments to reduce greenhouse gases, made in Paris in 2015, aren't enough to keep global warming from rising more than 1.5 degrees Celsius (2.7 degrees F) above pre-industrial temperatures.

Conservationists have developed a new high-tech strategy to trace the cartels that smuggle much of the illegal ivory around the world — by using DNA to track ivory back to specific ports.

Biologist Samuel Wasser from the University of Washington is behind the effort. He notes that while poaching in Africa has dipped recently, too many elephants are still dying.

Scientists working in South Africa say they've found the earliest known drawing. It was dug up in a cave where early humans apparently lived for thousands of years and left behind numerous artifacts.

A warming world could eventually make some of our most familiar ecosystems — deciduous forests, grasslands, Arctic tundra — unrecognizable.

That's the conclusion of a team of more than 40 scientists who took a novel approach to predicting the effects of how human-caused global warming will alter ecosystems. They looked about 20,000 years back in time.

More Americans die from the effects of heat than of any other form of severe weather, and this summer has seen one heat wave after another. Some places in the U.S. and elsewhere have recorded their highest temperatures ever. In fact, the average temperature around the planet over the past four years has been the highest ever recorded, and nine of the 10 hottest years were all in this century. (The other was 1998.)

A huge pack of floating ice along the northern Greenland coastline is breaking up and drifting apart into the Arctic Ocean — another consequence, scientists say, of global warming caused by the buildup of greenhouse gases in the atmosphere.

"We've never seen anything this large in terms of an opening north of Greenland," says polar scientist Ted Scambos of the National Snow and Ice Data Center, which collaborates with the National Oceanic and Atmospheric Administration.

Plastic trash is littering the land and fouling rivers and oceans. But what we can see is only a small fraction of what's out there.

Since modern plastic was first mass-produced, 8 billion tons have been manufactured. And when it's thrown away, it doesn't just disappear. Much of it crumbles into small pieces.

When a huge floating gyre of plastic waste was discovered in the Pacific in the late 1980s, people were shocked. When whales died and washed ashore with stomachs full of plastic, people were horrified. When photographs of beaches under knee-deep carpets of plastic trash were published, people were disgusted.

Though some of it came from ships, most, presumably, was from land. But how much was coming from where?