The Arctic is warming faster than thought
Climate change affects the sensitive system of the Arctic much more severe than thought. In a declaration from the Damocles symposium in Brussels the scientists conclude that "unless emissions are curbed significantly, we are not expecting a stabilisation of the Arctic's climate system".
The Arctic is warming faster than scientists have thought previously. Photo: Erlend Hermansen
During the last 100 years, the Arctic atmosphere has warmed almost twice as fast as the global average.
The sea-ice cover has rapidly thinned and decreased during at least three decades. The process is accelerating because the amount of heat required to melt the remaining ice is reduced. Moderate changes in heat flux from the ocean and the atmosphere can have large impacts on the Arctic ice cover.
Changes in the ice thickness and –cover lead to reinforcing feedbacks to the atmosphere and ocean. Earlier spring onset of snow melt on sea-ice, results in a decrease of the surface reflectivity to solar radiation, which warms up the atmosphere and enhances the melt. The reduced sea-ice cover results in more solar radiation absorbed in the ocean, which further heats up the atmosphere and reduces the ice extent.
Concerned by emission estimates
The September 2007 sea-ice extent was an all-time record minimum, and September 2008 and 2009 had the second and third lowest summer ice extents ever observed. Projection show that it might completely disappear in summer by the end of this century.
“The observed decrease of Arctic summer sea-ice extent over the last decades, results from a combination of strong natural variability of the coupled atmosphere-ice-ocean system and a growing radiative forcing due to rising concentrations of greenhouse gases. We are deeply concerned that the most recent CO2 emission estimates, are even higher than the most extreme IPCC-AR4 release scenario.”, it is stated in the declaration.
Severe consequences
The dwindling sea-ice will have serious consequences for indigenous livelihoods and cultures, for the exploitation of non-renewable resources such as oil and gas, for coastal and offshore fisheries activities, tourism and shipping. The abundance and distribution of important fish stocks will likely change, and we will have access to new and unexplored ocean areas for oil and gas exploration. All of which raise major environmental, economic, geo-political and governance questions.
In the declaration it says: “We need a high level of preparedness in terms of science and governance to cope with the expected increase of human activities in the Arctic.”
Calling for new Arctic policy
On top of the emission induced changes in the Arctic, scientists are observing decade-to-decade swings of the Arctic system which makes a reliable prediction very challenging and very much dependent on up-to-date observations. During IPY, scientists have had a unique opportunity to cooperate actively for a better knowledge of the Arctic regions.
“This effort should be maintained specially now when environmental changes are altering the geo-strategic dynamics of the Arctic. Potential consequences for international stability, call for the development of a policy protecting and preserving the Arctic, promoting sustainable use of resources and contributing to enhanced Arctic multilateral governance.”, the scientists conclude in the declaration.
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