During spring and early summer as the seasonal temperatures rise, shallow pools of water form on the surface of Arctic sea-ice. These so-called ‘melt ponds’ are important for the ice’s albedo – a measure of how much sunlight is absorbed by the ice and how much is reflected back into space.
This is key because larger areas of melt pools mean that more heat is absorbed by the sea ice, which causes it to melt further, and in turn absorb more heat.
Now, an international team of researchers headed up by the British Antarctic Survey (BAS) have used a cutting-edge climate modelling system developed UK Met Office’s Hadley Centre to estimate that the impact of intense springtime sunshine created many melt ponds may leave the Arctic sea-ice free by as soon as 2035.
Read more about the Arctic:
The team based their predictions on data gathered on the last interglacial – the interval of warmer global average temperature lasting thousands of years that separates consecutive glacial periods within an ice age that occurred 127,000 years ago. The current interglacial period began at the end of the Pleistocene, about 11,700 years ago.
“High temperatures in the Arctic have puzzled scientists for decades. Unravelling this mystery was technically and scientifically challenging,” said joint lead author Dr Maria Vittoria Guarino, Earth System Modeller at British Antarctic Survey (BAS).
“For the first time, we can begin to see how the Arctic became sea ice-free during the last interglacial.
“The advances made in climate modelling means that we can create a more accurate simulation of the Earth’s past climate, which, in turn, gives us greater confidence in model predictions for the future.”
The finding highlights the importance of incorporating melt pond data into climate models and tackling climate change as a matter of urgency, the team say.
“We know the Arctic is undergoing significant changes as our planet warms. By understanding what happened during Earth’s last warm period we are in a better position to understand what will happen in the future,” said Dr Louise Sime, the group head of the Palaeoclimate group and joint lead author at BAS.
“The prospect of loss of sea-ice by 2035 means we should really be focussing all our minds on achieving a low-carbon world as soon as humanly feasible.”
Reader Q&A: Could we move polar bears to Antarctica to prevent their extinction?
Asked by: Max Barber, London
Polar bears rely on sea ice to be able to hunt seals. The ice is shrinking from Antarctica just as rapidly as it is from the North Pole, and in fact tends to be thinner there anyway, so that doesn’t really help.
In theory, polar bears could probably adapt to hunting penguins on land, but this would have a devastating effect on penguin communities, some species of which are already endangered or vulnerable.