Greenland’s Ice Melting

  • Greenland’s ice is starting to melt faster than at any time in the past 12,000 years, research has shown, which will raise sea levels and could have a marked impact on ocean currents.
  • The increased loss of ice is likely to lead to sea level rises of between 2cm and 10cm by the end of the century from Greenland alone.
  • Greenland’s ice sheet shrank between 10,000 and 7,000 years ago, and has been slowly cumulating over the past 4,000 years.
  • The current melting will reverse that pattern and within the next 1,000 years, if global heating continues, the vast ice sheet is likely to vanish altogether.
  • If greenhouse gas emissions continue to rise strongly, the rate of melting could accelerate further to be four times greater than anything found in the past 12,000 years.
  • Recently, a separate team of scientists found that melting of the Antarctic ice cap would continue even if the world met the Paris agreement goal of holding temperature rises to no more than 2C, and would eventually raise sea levels by 2.5 metres at that level of heating.
  • Arctic sea ice is also melting at a fast pace. This year’s summer sea ice minimum was the second lowest in the last 40 years of continuous measurements.
  • Unlike Greenland’s ice sheet, which sits on land, the Arctic ice cap floats and so its melting will not produce much impact on sea levels.
  • However, its melting hastens warming further by reducing the earth’s albedo – the reflection of light back into space from the ice – and exposes the darker water underneath, which absorbs more heat.
  • They checked their findings through satellite measurements and other instruments, and also by mapping the position of boulders containing beryllium-10.
  • These are deposited by glaciers as they move, and measurements of beryllium-10 can reveal how long the boulders have been in position, and therefore where the edge of the ice sheet was when the boulder was deposited.