Near sea-level home owners concerned about recent dramatic reports of Greenland glacier break-up and its possible effect on sea level can take a little heart in a recent study showing a compensating thickening of the Antarctic ice sheet.

Sea level is currently rising at about 1.8 millimetres per year, largely through melting of the Greenland and Antarctic ice sheets as a result of global warming, climate specialists have warned.

However, the experts also expected that climate change would trigger an increase in snowfall over the Antarctic continent, as increased evaporation from the oceans puts more moisture into the air.

Now a survey has directly measured increased snowfall over a large area of Antarctica that is thickening the ice sheet and slowing the rise in sea level caused by melting ice.

A satellite survey by the British Antarctic Survey shows that since 1992 the East Antarctic ice sheet gained enough ice to reduce the oceans' rise by 0.12 millimetres per year.

It’s only a small compensation, but the survey equipment can only measure ice that is very flat. Ice formed on the slopes and especially around the coastline cannot be measured. A new satellite system called CryoSat due to be launched later this year by the European Space Agency will be able to take accurate measurements and uncover the truth about Antarctica's ice balance.

Scientists think that Antarctica is responsible for about a third of the world's sea level rise.

David Vaughan, a glaciologist at the British Antarctic Survey said, "These effects have been predicted for a long time, it's just that no one has measured them before."

Vaughn warns that thickening of the ice sheet should not be seen as a long-term protection against a rise in sea level. Parts of the Antarctic Peninsula, which stretches towards South America, now regularly hits temperatures above 0 °C in the summer, leading to direct melting of the ice there. As the world heats up glaciers in West Antarctica will accelerate their melt rate while snowfall may reduce.