Greenland rising as ice melts

Greenland’s bedrock rose significantly last year due to the loss of 100 billion tonnes of ice during the particularly warm summer.

Researchers from Ohio State University found that during 2010, part of country’s landmass rose more than half a centimetre more than in recent years.

The data were collected from GPS stations which usually record an average uplift of about a centimetre per year in the Arctic country.

“But a temperature spike in 2010 lifted the bedrock a detectably higher amount over a short five-month period – as high as 20 mm in some locations,” Michael Bevis, an geologist from the POLENET research network told a conference of the American Geophysical Union this week.

He added that the changes must be due to the increased ice loss. “Really, there is no other explanation. The uplift anomaly correlates with maps of the 2010 melting day anomaly. In locations where there were many extra days of melting in 2010, the uplift anomaly is highest,” Bevis said.

For every 100 billion tonnes of loss from the Greenland ice sheet, global sea levels are thought to increase by around 0.25mm. “Pulses of extra melting and uplift imply that we’ll experience pulses of extra sea level rise. The process is not really a steady process,” Bevis said.

(Photo: Anders Peter Amsnæs)