Regional changes, global effects: an interview with IPCC Arctic specialist Jan-Gunnar Winther
Climate change is affecting the Arctic further and faster than any other part of the world. Carbon Brief speaks to Intergovermental Panel on Climate Change (IPCC) lead author Jan-Gunnar Winther about how the new report from the UN panel on the impacts of climate change relates to this highly sensitive region.
What are the three main messages in the IPCC report concerning the Arctic?
First, it’s important to stress that climate change with an anthropogenic component is having a greater effect in the Arctic than in other parts of the world, according to the report.
Second, it shows that we now have quite substantial knowledge that change in the Arctic region is having an effect on weather and climate in the northern hemisphere. We now know that regional changes – particularly in the Arctic – can have global effects.
And third, the report indicates that climate models have so far failed to give us accurate projections for the future of the Arctic. Over the past 20 years, they have systematically underestimated the rate of change in the Arctic. For example, the reduction in summer sea ice extent and thickness has been far beyond that predicted by models.
We must be aware that the future could bring yet more surprises in the region.
In which areas of Arctic science has the report made the greatest progress?
We have got more data, better models, and more significant findings since the last IPCC report came out in 2007. Findings are firmer and more precise, and we can be more confident of the likelihood of some effects.
For example, we have gained a great deal of knowledge on how climate change will affect the mass balance of glaciers. One very significant finding has been that the loss of mass from the Greenland ice sheet and from Antarctica is accelerating.
This also feeds into our understanding of climate change around the world. For example, the loss of mass from the Greenland ice sheet gives us a higher certainty on how far sea levels will rise as a result of ice melt.
What about other areas of ice melt?
Meanwhile the large reductions we’ve seen in summer sea ice in the Arctic don’t affect sea level rise, but have other local and global implications.
On a local level, Norway is having a national debate about whether to do oil and gas exploration in the Barents Sea. Here, the sea ice retreat is particularly fast, opening up areas for new activities like energy and transportation, mineral extraction, fisheries and tourism.
But the loss of this ice, which forms a reflective blanket over the sea will also have huge global implications as the Arctic Ocean will absorb more energy over a larger area when sea ice is replaced with open water, influencing global climate and weather. This is a relatively new area of research in which we’re making great progress.
Changes in the Arctic are most closely linked to weather in the northern hemisphere. But we now have confidence that changes in weather systems can affect the monsoon, as well as floods and heatwaves in Asia, as well as Europe and North America. Science should work continuously to find out how the Arctic plays in concert with the rest of the world.
And in what other areas are we already seeing changes since the last report was out?
I have most expertise in researching the European part of the Arctic, and this area is already seeing dramatic changes in the ecosystem.
From year to year, creatures like fish, algae and plankton are moving northwards. We’re seeing completely new species, as well as old species in new areas.
This has spurred a change in the whole fishing fleet as commercial fisheries follow the species. Arctic cod is the main catch of the Barents Sea fisheries and one of Europe’s most important marine food sources. Last year, the catch was one million tonnes, reflecting an increase in volume – but the population is also migrating northwards.
New species have also been spotted. Herring have been seen for the first time in Svalbard this summer. Another new commercially exploitable resource is snow crab, which has, we think, migrated into the Barents Sea. Catching snow crab generates $7billion of income in North America, and could be an important new fishing resource in the European Arctic, too.
But just as there may be winners in this story, there will also be losers.
Polar bears’ food plate is shrinking year by year as Arctic summer sea ice disappears, and they are already red listed as a threatened species. And for marine species that move northwards, there are likely to be fishing fleets in the seas they leave behind that will no longer be able to catch them.
The latest science shows that climate change is part of a complex and unpredictable picture in the Arctic.
Some reports have focused on the local changes the IPCC predicts in the Arctic. Is there a danger that by fixing on one aspect of the report, they risk ignoring the bigger picture?
There are extremely important local changes happening in the Arctic region. Fisheries are opening up, there may be new opportunities to extract resources and there could soon be access for transport and increased tourism. On the other side of the equation, some groups and species stand to lose out. Individual countries will have to balance their national interests in order to explore the region’s resources in a sustainable way.
But there is a danger that these local opportunities could distract from the huge global effects these changes could have. The Arctic region is no longer decoupled from the rest of the world.
This is already reflected to some extent in international politics. The Arctic Council is increasingly shaping policy in the region, and could play an important role in balancing the different interests at play. It has admitted a large number of observer countries – to the extent that 60 per cent of the world’s population is now represented around the table, from countries with an economic interest in the Arctic to those that fear changes in the Arctic will affect their environment.
How would you summarise the IPCC’s findings as they relate to the Arctic?
The Arctic is at the centre of a huge, dynamic system – and its response to climate change extends far beyond the region itself.
Climate models have consistently underestimated the rate of change in the Arctic and must be improved so that we can start to work from more precise projections. This is essential both for management of the region and for global weather and climate projections.
As the increased interest in the Arctic shows very clearly, this region is very important for all of us.