A poignant reminder of the strengths and frailties of our species

Me at the grave of Ernest Shackleton at King Edward Point on South Georgia, trying to take it all in. Photograph: Helen Czerski

Location

52° 54.14 S
49° 37.10 W

Tomorrow, my world will both expand and shrink. The ship will get back into port and this part of our scientific adventure will be over. My daily life will no longer be limited to the innards of this giant floating tin can, and I'll be free to walk in any direction, to cast off the routine of the ship and to use as much internet bandwidth as I like.

My world will be a bigger place. But I'll also lose the opportunity to walk up to the top of the ship, look out over endless ocean in every direction and allow my imagination to expand enough to understand how large our planet is. Without that daily reminder, my world will shrink.

This week has been visually stunning. For me, the best bits of the past six days put the whole month's science into perspective. The most memorable sights were a glacier, 10 penguins and a grave.

Ice is one of the most striking features of our planet. It's stacked up over Antarctica and Greenland in vast white fortresses known as ice caps, and the polar oceans are patrolled on a yearly cycle by battalions of sea ice. But this intimidating frozen architecture is really just ocean that got lost.

Water evaporates from the oceans all the time. If the wind then carries it over land and dumps it as snow, it's stuck there until it thaws. But sometimes on Earth, it's so cold at the poles that the thaw never comes. More and more water is taken from the oceans, piling up until the snow from thousands of years has built snowdrifts the size of continents. This is the situation now.

But that's not the end of it. Pulled downwards by gravity, this ice slowly scrapes its way across the land in giant ice rivers called glaciers, back towards the ocean. Thousands of years after those water molecules last melted, they fall off the front of the glacier and return home.

The Ross Glacier, South Georgia. The thought of this ice marching seawards for thousands of years is incredible. Photograph: Helen Czerski

On Thursday morning, we were face to face with a wall of blue ice that last saw sunlight thousands of years ago. The glacier was colossal. The geologists were busy collecting mud cores from the ocean bed beneath us. Depending on the balance of new snow and melting, glaciers advance or retreat. The story of this glacier is written into the bottom of the fjord, and they were digging it up.

Ice like this is more than just visually stunning. It's one of the five great systems of the Earth: rock, air, ocean, ice and life.

South Georgia has all five and it's one of the most beautiful places I've ever seen. The highlight of this whole month was a few hours ashore at King Edward Point on Friday.

A group of king penguins in a vast landscape on South Georgia in the South Atlantic. We sat and watched for nearly an hour. Photograph: Helen Czerski

The penguins this time were king penguins, a group of six adults, three half-grown chicks (slouching brown lumpy feather dusters, lacking any of the elegance of their parents), and one very new chick peeping out from between the feet of an adult. We sat just a few metres away, watching them stand and wait and preen.

Behind the penguins was a huge flat green meadow bounded by towering mountains, which were bare except for the ice on top. Hidden in the meadow were fur seals and elephant seals, which sounds idyllic until they wake up and snarl at you.

There are epic landscapes and then there are epic snoozes. These male elephant seals have turned epic snoozes into an art form, while still managing to belch and gurgle almost continuously at the same time. Photograph: Helen Czerski

Here, some of the interactions between the Earth's five component systems are obvious. Ice scours the rocks, giving them a distinctive shape. The resulting dust blows into the ocean, fertilising it and helping tiny plants to grow. These feed larger animals that feed the fish eaten by the penguins and seals. The carbon in that food goes back into the atmosphere as carbon dioxide when the animals breathe out, and it's eventually absorbed back into the ocean to start all over again.

It's these complexities and many more – the intricate dance of our planet – that we've been studying on this trip. Being able to soak up this landscape for a few hours really brought that home.

This cruise has brought mixed results for me. There weren't as many breaking waves and bubbles to measure as I'd have liked, but I'm happy with the data that I have, and I've learned a lot about this environment. Analysing the data we have collected will add more jigsaw pieces in our understanding of our planet. Overall, it's been a scientific success and I'm very relieved about that.

At King Edward Point, there's a small square of land that's protected from the seals by a white picket fence. Inside is the grave of Ernest Shackleton, one of the greatest polar explorers of his day. It's a reminder of both the strengths and the frailties of our species. Humans only reached the South Pole one hundred years ago, and there is still so much to learn about Earth.

We've come a long way since Shackleton pitted his wits against the Antarctic lands and seas, but we have much further to go and it's becoming more important every year. I'm happy that I can do a little bit to help. Isn't science fantastic?