A warning from the north

I’ve just returned from fieldwork in Svalbard, the island archipelago situated halfway between Norway and the North Pole. Straddling 81˚ to 74˚N, this near-pristine environment is a haven for researchers interested in Arctic environments.  I’ve been extremely privileged to visit some beautiful places in the world but was blown away by Svalbard. The islands are a heady mix of mountains, ice and 24-hour summer daylight that was totally different to anything I had ever experienced before. I was there as part of a University of Exeter research team to look into the impacts of past climate change, funded by the Leverhulme Trust.  For two weeks, we boated, trekked, dug and probed our way into Svalbard’s recent geological past. As the ice has retreated back from its maximum limits at the end of the last ice age, the land has risen out of the sea, exposing ancient landforms and sediments that preserve a fabulous record of what has happened in this part of the world over the past 20,000 years.  

Sampling in Svalbard
A key question scientific and political circles is what might happen in this region in the near future.  Without a major effort to cut the level of carbon in the atmosphere, the Intergovernmental Panel on Climate Change (the IPCC) has warned the world could be up to 6.4˚C warmer by 2100. Disturbingly, we know from ancient archives that the high Arctic experiences a far greater change in temperature than the global average. The region already is suffering some of the earliest effects of human-induced climate change, many of which have been spectacular. In September 2007, the fabled 5000 kilometre long waterway known as the Northwest Passage opened up as a navigable route without the need for ships armed with ice breakers. For centuries, finding a path through the region had been the stuff of dreams. Celebrated endeavours have been made over centuries to find an opening between the north Atlantic and Pacific but most revolved around ships smashing their way through the ice, or in the case of some Victorian expeditions, resorting to cannibalism when all hope was lost. More success has been had along Russia’s northern shore – the so-called Northeast Passage – but the going was still tough. It’s been 130 years since the first successful navigation of the Northeast Passage when the Swedish steam barque Vega managed to make it’s way through this route, reaching Japan in September 1879 after a hard winter locked for ten months in the sea ice off the Siberian coast. Since the summer sea-ice low of 2007, ice coverage has fallen even further, opening up the Northeast Passage completely and allowing the North Pole to be circumnavigated in 2008 for the first time in recorded history. It’s not taken long for the commercial opportunities to be realised. This year, the first trading ships passed through the Northeast Passage, a worrying indication of what might come to be the norm.  But why are such big changes experienced this far north? 

The key reason for this is that although the amount of sea ice cover in the Arctic waxes and wanes through the year, temperatures have steadily risen through the second half of the twentieth century; on average by some 0.5 °C a decade. A recent paper led by Darrell Kaufman of the Northern Arizona University and published in the international journal Science has shown that this warming has happened against a backdrop of cooling temperatures over the past two millennia that was driven by the changing orbit of the Earth around the Sun which contrived to cool the Arctic. Importantly, Kaufman’s team found four of the warmest five decades over the last 2000 years was experienced between 1950 and 2000. The cause is increasing greenhouse gas levels in the atmosphere, disrupting the natural system and warming the region some 1.4˚C more than it would be if the natural cooling had been allowed to continue uninterrupted. The amounts involved may not sound much but the rising mercury has been instrumental in changing the nature of the sea ice across the Arctic.

During the hedonistic summers of the 1970s there used to be over 50 per cent ice cover in the Arctic, but by 2008 this had crashed to less than 30 percent.  As the cover has dropped, so too has the thickness of ice. During the Cold War, UK and US military submarine missions in the Arctic would routinely direct their sonar towards the surface to work out whether they could punch through the surface in an emergency and launch a missile at Moscow. Much of the submarine data has now been released, providing a treasure trove of valuable data. Put together, the data show a disturbing trend: the ice is getting thinner and on average younger. In the 1980s over 20 per cent of the Arctic sea ice was at least six years old but by 2008 this had declined to just 6 per cent. The thinner the ice, the less likely it will survive through the summer and the harder it is for the subsequent winter to build ice levels back up at the surface. This all has big climatic implications beyond the Arctic. Because the sea ice is so reflective, around 90 per cent of the heat received from the sun at these latitudes goes back out to space, making this region a massive natural refrigerator that help keeps our planet cool. The problem is as the ice cover goes, the summer heat is absorbed by the ocean and rereleased back into the atmosphere later in the year when the next phase of sea ice is supposed to be forming; autumn temperatures are now a staggering 5˚C above normal for the region.  As the oceans warm the overlying air, these temperatures start to reach far inland, melting areas of permanently frozen ground in the region. Year on year, these feedbacks become stronger, accelerating the loss of ice cover and increasing the warming over the region relative to the rest of the planet. As a result, recent Arctic warming is almost twice that the global average.

While we were in Svalbard, the United Nations Secretary-General, Ban Ki-moon, visited to learn more about the effects of climate change in the region. His stay raised the international profile of a fragile environment in a rapidly changing world and highlighted the genuine concern that momentum is slipping from getting a deal in Copenhagen later this year. The nations of the world are supposed to be meeting in Denmark in December to thrash out a new deal to replace the Kyoto Protocol which expires in 2012, with the aim of significantly cutting future greenhouse gas levels in the atmosphere. Unfortunately, the negotiations seem to be slowing down. A major stumbling block appears to be just how much the developed world will cut emissions and what expectations can be placed on developing countries growing their economies in the future.

To try to get things back on track for Denmark, Ban Ki-moon yesterday hosted a UN summit on climate change in New York in an attempt to get a firm commitment from world leaders to set clear targets for emission reductions. There were some encouraging signs from the developing world. China announced a major change in policy by declaring it would increase the use of non-fossil fuel energy sources to 15 per cent and aim to significantly reduce greenhouse gas emissions by 2020. Although a precise target was not given on just how much less would be put in the atmosphere, this was a major shift in stance for China which had publicly rejected calls to cut emissions. Just before the meeting, India announced it was looking to invest a massive US$19 billion in solar energy as part of a bigger policy move to cut emissions; a promising move for a country where each person emits a quarter of the world average of greenhouse gases.  Whether the developed world can make the necessary cuts remains to be seen.  Japan is one of the most hopeful, declaring in New York that by 2020 it will cut the amount of carbon gases it puts into the atmosphere by 25 per cent (relative to 1990); up from its previous position of just 8 per cent.  President Obama has been a little more circumspect on actual targets but is at least signalling the United States is willing to take a lead role in forging a deal, a promising sign that the intransigence of the previous eight years has ended. Meanwhile, the European Union has committed to a target of 20 per cent carbon emission reductions by 2020 while British Prime Minister Gordon Brown has become the first world leader to declare he will go to Copenhagen to help achieve a deal and urged others to join him.

Will world leaders pull the iron out of the fire and get a deal?  I do hope so.  I love Svalbard and would hate it to become a property hotspot in a warming world.

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