Victoria Gill

Oh, really?

Ian Van Nest is a ranger for the Polar Bear Alert programme in Churchill, Manitoba. It's his job to move bears away from the town and from people.

In a warming Arctic, living alongside polar bears is becoming even more complicated. So while Ian and his colleagues keep bears and people apart, conservation scientists head to Churchill every year because as the sea ice forms here at the start of winter, the bears gather, waiting.

Elisa McCall is from the organisation Polar Bears International.

The ice-free summer period when bears aren't able to hunt is now about a month longer than it was in the 1980s. And in that time, this area has lost about half its polar bears.

Monitoring and studying polar bears here is a research team that we're tagging along with on the subarctic tundra a few miles from Churchill. About an hour into our trip, a young male bear approaches. There's a polar bear under our tundra boogie right now. He's very curious about us. My heart's really beating.

That's Polar Bears International's Geoff York. If bears are spending more time on land, does that mean there's more of a period where they're likely to be closer to people?

So for now, Churchill has to deal with hungry polar bears waiting for longer on shore. But in the long term, the sea ice that brings the polar bears and thousands of tourists here every year is melting away.

Dave Daly runs Wapusk Adventures, and he's raced sled dogs across the Arctic.

The disappearance of the sea ice here could transform this environment. That's why a new research facility that opened just this year is pumping cold water from the Hudson Bay into the laboratory to study it. Professor Fei-Yu Wang is a senior researcher at the new Churchill Marine Observatory.

Because essentially that seaway has been blocked by the ice. And that ice is retreating. This is a town preparing for a less icy future. But the fate of its polar bears depends on us and whether we can rein in rising temperatures and preserve that sea ice that they depend on. That report by Victoria Gill.

And so what was the state of that mental health did you find?

And were there any countries that stood up for you that were worse off before or that had gotten worse or some which were doing better?

We know that some of the countries that you are looking into, you just mentioned Mongolia, some of them will not be rich countries. They will not have enough resources. So what is the support system there to help those who've come or who've told you that there is, you know, they have anxiety, that they are a bit depressed?

And that could reveal some vital clues about the health of the Antarctic marine food chain. Victoria Gill.

The sheer number of these tiny beasts means that collectively they weigh an estimated 400 million tonnes. That is similar to the combined weight of every human on Earth. But they are difficult to monitor. They are small and the Southern Ocean is very big. They also move around in these swarms on the ocean currents.

So this latest mission developed by scientists from the charity WWF and the University of Strathclyde aims to measure them from space. Here's how. A team of scientists has already visited Antarctica on a research mission to catch live krill and then measure how their presence changes the amount of light that seawater absorbs. As you add krill to the water, its colour changes.

And that, the researchers say, can be applied to satellite images of the ocean. There are, of course, already satellites capturing high resolution images of Antarctica. So while we won't be able to see individual krill in those pictures, what we could get, scientists say, are snapshots of their density at the surface of the ocean.

Fogwater harvesting is what it sounds like, capturing water from clouds of fog. It's already in use and has been for decades, but on a small scale, mainly in rural settings. And it's actually really simple. You hang a fine mesh, usually a plastic mesh sheet, between two poles.

The moisture-laden fog cloud passes through the mesh, droplets of water form on it and you collect that, pipe it away and store it. One of the biggest fog harvesting schemes is in Morocco, but it's also in use in coastal Peru, Mexico and Chile, where you get these big Pacific sea fogs that move onto the land. And that's where a group of researchers have been looking at scaling it up in Chile.

They say that large-scale fog harvesting could provide some of the driest cities in the world with drinking water. And they've demonstrated this in a study that's based on Alto Hospicio. That's a city of almost 150,000 people on the edge of the Atacama Desert. Alto Ospicio ist ein besonders besonderer Fall, wenn es um die Bedürfnisse für Wasser geht.

Es ist in einer sehr trockenen Region, weniger als fünf Millimetern Regen pro Jahr fallen im Übrigen in dieser Region. Und viele urbische Bereiche in Nordchile, inklusive Alto Ospicio, bekommen die meiste ihrer Wasser aus Untergrund-Aquifers. Und es gibt eine Menge Anforderungen auf diese Aquifers, nicht nur aus Städten, sondern auch aus Industrie und Mining.

So this research team that's led by scientists at Universidad Mayor in Santiago has carried out tests of fog harvesting systems and combined their results with satellite images and weather forecasting in Alto Ospicio.

And what they've come up with is exactly where you should place large-scale fog harvesting setups and how much water they could be expected to collect on average every day in the city.

The researchers worked out that with 17,000 square meters of fog-harvesting mesh erected in large areas in foggy hotspots around this desert city, which there is plenty of room for around Alto Ospicio, you could provide enough drinking water for all of the urban slums in the city.

They're now also working on a fog map of the entirety of Chile, because they say that in places with the right conditions, particularly where you have mountains that meet the ocean, we should be harvesting from the clouds to provide much needed clean water for people who need it.

This is a story with some very tiny main characters, the Desertus Island land snails. They were rescued from the brink of extinction and brought to Chester Zoo, where they've been living and breeding inside this converted shipping container.

There are two snail species that the team are bringing back to their wild island home off the coast of Portugal. Discular snails and the even smaller Geometra. They're prepared for their journey with a little scientific makeover.

Why do they need to be marked?

The desertus islands close to Madeira in Portugal are their destination and their natural home. The largest of the islands, where the last snails were found, has had its habitat decimated, eaten away by goats, rats and mice that were brought here by people. So the team has transported the snails to the protected neighbouring island of Bugio. It's meant a long and precarious journey.

After waiting for the ideal cooler evening conditions, it's finally time to set the snails free.

This is a small but significant part of a mission to restore the natural habitat and wildlife on these mountainous Atlantic islands. If it goes well, more snails will be brought here next year, each bringing a small splash of colour back to their habitat. Victoria Gill.

The discovery that oxygen, which is vital for life, was being made in the dark on the seafloor confounded marine scientists when it was announced.

The discovery that oxygen, which is vital for life, was being made in the dark on the seafloor confounded marine scientists when it was announced. It's widely accepted the gas is produced by plants in sunlight using photosynthesis. But down where sunlight can't penetrate... Scientists found oxygen levels going up.

The seabed they studied is covered with nodules of metal that have built up naturally over millions of years. It's these nodules that researchers say produce the gas. If they detect oxygen they'll then carry out detailed experiments to understand exactly how it's being made.

With VOA employees being now placed on paid leave for the time being, does that mean that you've stopped broadcasting?

Mr. Markov, let me ask you something. You said that the reason for this war is partly because there is a real threat to security to Ukraine and Russia. Yet it was Russia, your country, that aggressed and invaded Ukraine.

You call it humanitarian operation. Let me ask you then, Mr. Markov, with this war that Russia waged against Ukraine, does Russia respect Ukraine's sovereignty?

It exists because it's a country. It's a country that is recognized by war.

And so do you find or do you think that there is a danger in doing that and engineering animals in that way?

And in your opinion, where could this kind of research then lead us into the future?