How many swimming pools of water is Greenland losing each year?
The short answer is about 100 million Olympic-size swimming pools a year.
The BBC is currently showing a series called Arctic Live looking at the seasonal transitions that happen in the Arctic, including the ecology and climate. Unfortunately as we are in Denmark we cannot watch the Arctic Live programme but an inaccuracy caught our eyes which we would like to correct.
The BBC stated in a tweet and on their facebook page that Greenland is losing 110,000 Olympic swimming pools of water a year.
However, this number is far too low.
Each year the ice sheet loses around 250 Gigatonnes of water. This is about 100 million Olympic sized swimming pools a year, not 110,000 pools.
Another way to think about the amount of water Greenland is currently adding to the oceans is that it roughly corresponds to about 4 litres per person per hour assuming that the human population is 7.4 billion people.
We assume in this calculation that each swimming pool is 25m wide, 50m long and 2 m deep and contains 2,500,000 litres of water. Most likely a few zeros went missing in the social media outreach.
On the Polar Portal we show the total amount of ice lost using data from the GRACE satellites on this page:
Left: GRACE data shows how much ice the Greenland ice loses each year. Right: A meltwater stream in Eastern Greenland.
The offending tweet: