Snow, icebergs, glaciers, continental ice sheets. If it's white and cold, it's part of the earth's cryosphere. And it shouldn't come as a surprise to learn that that is getting smaller, working out what's melting and where is importance. And up here, nearly three and a half thousand meters above sea level, we've come to the high altitude research station overlooking the Aletsch glacier in the Alps.

Switzerland is home to 1400 glaciers, of which Aletsch is the biggest. And it's here that we find groups of scientists developing new techniques to watch the ice and snow and monitor their retreat.

Glaciers are more water reservoirs that we.

Have, which is important for groundwater repletion. I think this is an important fact. But also, if you lose this mass, you have instability in the mountains, so you have more landslides ongoing, more erosion.

It is also a cause of natural hazards, avalanches, if there is a lot of snow and rock falls and similar things if there is not enough snow and the ground destabilizes. A very important one in terms of the energy transition is the hydropower generation. Hydropower generation uses the water that runs down from the mountains. And if there is not enough water, they cannot generate enough power. And if there is a lot of water, a lot of snow, they actually need to know this in advance. To plan the generation for all this, we, of course, need to know where the snow is, because that is the water of the future.

There are two new methods being developed.

Here to not just monitor the surface, how much it's melting, how fast the glacier is moving, and so on, but also to find new ways of seeing below the surface.

These two top antennas are transmitting antennas, and here we have a set of receiving antennas.

So they're two different radars. This gives us a different angle and perspective, and with this, we can get an extra information that otherwise we will not be able to acquire.

Esther and Marcel's team is using radar to penetrate deep into the snowpack. Now, different formations of ice crystals reflect the signals back in different ways, revealing the internal structure of the snow, how deep it is and how dense it is.

After several weeks of taking measurements on.

Snow cover across the glacier, the team will spend the next few months evaluating that data to discover whether radar really can shape future studies. But from the ground, you can only see so far. To get a wider view, you need the second method and go even higher up than this.

The space measurements are needed to cover the area. It is simply impossible to cover a large area like the entire Alps with ground based measurements.

Conrad's project is training an AI system to predict what will happen to the snow next.

The system has been trained on images.

From ESAS Sentinel two satellite network.

These are a mix of optical photographs.

That wed see with the naked eye.

Images in the infrared and some created using longer wavelength radio waves like Marcel and esters ground based system.

What our model effectively does is it creates a time series the satellites pass over every couple of days and its like a very slow motion video of the surface and we acquire this video and process it. In our case we have a local snow depth pattern and we want to predict with the help of the sequence and also the new observation, what will be the next snow depth pattern.

Now these techniques are still in the experimental stage. If the teams can improve their methods then they will no doubt prove invaluable in monitoring how the warming climate is changing snow cover around the world.

For example, in Greenland we have a huge area where we are looking for.

Supraglacial lakes, we call them, which are lakes beneath the snow. The mount of lakes are giving an indicator also of global warming.

And we can detect these lakes actually with radar signals that are built up.

In summer where you have no snow on top, and in winter, where you have the accumulation of snow, you can.

Still see them beneath.

In fact, these techniques could be used even further afield.

We have radar systems which are observing.

The Venus for example. And on Venus we have a very strong atmospheric contribution and in order to go through this atmosphere we need longer wavelengths, so radar wavelengths to penetrate through it and then to see or to characterize really the surface of Venus, it.