The frost report

Hamish Pritchard spends his days exploring glaciers in the Antarctic - from an office in Cambridge. Thank goodness. It's armchair glaciologists like him who could save the world from global warming

I've been working for the British Antarctic Survey for two years now, but in that time, I haven't been south of Worthing. Each October I wave goodbye to the ice-core drillers and snow experts, the geologists, the biologists and meteorologists, and return to my office to crunch some pictures through a computer. For them, four months of snow and ice, blazing sunlight and biting storms. For me, East Anglia.

I've been working for the British Antarctic Survey for two years now, but in that time, I haven't been south of Worthing. Each October I wave goodbye to the ice-core drillers and snow experts, the geologists, the biologists and meteorologists, and return to my office to crunch some pictures through a computer. For them, four months of snow and ice, blazing sunlight and biting storms. For me, East Anglia.

But, despite my wanderlust for the great icescapes of the Antarctic, the greatest progress in our understanding of the Antarctic ice sheets is currently being made by scientists like me, who stay at home. In many ways, we are the new explorers of the world. With last week's news of glaciers beating a retreat all along the Antarctic Peninsula, this sort of environmental work is all the more important.

If there's one inescapable truth about Antarctica, it's this - as a species we're not meant to be there. This is obvious to most of us, of course. We can imagine the gales, the empty wastes and bitter Southern Ocean - and we know what happened to Scott. Even the best-organised survey teams on the ground can't hope to leave their footprints on more than a tiny fraction of the huge continent before the sun starts going down and the next Antarctic winter draws in. So we turn instead to technology.

In the last decade or so, satellite data has told us, almost to the centimetre, how fast many of Antarctica's glaciers and ice streams are flowing as they drain the continent of ice, and even how much snow has fallen over past centuries. Now lasers and radar transmitters on a pair of new satellites, Nasa's ICESat and the European Space Agency's CryoSat (launching later this year), will look for tiny changes in the height of the ice sheets so that we can see whether they are growing or shrinking. These satellite maps give us millions of measurements covering vast continent-sized areas and are delivered right to our desks: contrast this to the picture of our colleagues in the pre-satellite years, when each single measurement was hard won by small field parties and dog-sled teams surveying again and again a handful of stakes knocked into the snow. The satellites don't care about the cold, the long winter night or even the storms. They just keep spinning round, beaming radar signals through the cloud and the dark and sending back the pictures.

Much of our work is in squeezing meaning from this wealth of satellite information - I peer at a screen and not a mountain range. But what are we seeing in all this data? In some places, things are changing far more than expected. In the early Nineties, people started to study the ice shelves on the Antarctic Peninsula and found them to be shrinking. The temperature records showed uniquely fast warming in the region (2.5 degrees in only 50 years), and over a few warm days in the summer of 2002, the 500-billion-ton Larsen B ice shelf disintegrated with shocking speed, watched only by a passing satellite.

In the last few weeks, my colleagues have shown that 87 per cent of the glaciers on the Peninsula are retreating, and their retreat is getting quicker. Now, I'm going through the archives of images to see whether these glaciers are flowing any faster as they warm. If they are, that means more ice lost, contributing to the rising seas. The potential for future change is much greater and there is a fear that the retreats we've seen, the crumbling round the edges of West Antarctica, could be the first signs of a more serious collapse that, through sea-level rise and knock-on climate effects, could change the map of the world. The steady drip of reports on environmental change is becoming a flood, and this makes ours an exciting topic to work on.

But the satellites can't tell us everything. They give us no more than a broad view of the continent's skin. Now more than ever, it's essential that we go there to delve more deeply and to fill in the gaps, and what's more, we want to. There's something even more than the science that drives people to study places like the Antarctic and to go out and experience them, cold winds and all.

I think that for many people the reason is less tangible and not often acknowledged, but is something to do with the way that we, comfortable in our daily lives, feel about wilderness. When the planes and ships leave Britain each year and head south again, there's a sense of great anticipation for the wild, unpredictable, overwhelming nature of the place where humans are not meant to be. While we can do so much at home, I hope it's me going next time.

Dr Hamish Pritchard is a glaciologist for the British Antarctic Survey. Details of the survey's work can be found at www.antarctica.ac.uk