"Record setting changes" throughout the Arctic

  • 02 Dec 2011, 14:00
  • Christian Hunt
Rapid change is underway in the Arctic, with significant changes in sea ice patterns and knock-on effects on the oceans and soils of the region, according to the annual 'Arctic report card' from US scientific body NOAA.

The assessment, which summarises the scientific literature on the region from the past year, makes it clear that the Arctic is continuing to experience "the impacts of a prolonged and intensified warming trend".

With more open water in the Arctic ocean for longer, and as the upper layers of the sea become warmer, and less salty due to melting ice, scientists have been observing significant changes in what's happening beneath the waves. The ocean is becoming more acidic, and this is acccelerating, as more open water means faster uptake of carbon dioxide. At the same time, life is blooming - over the past ten years or so satellite data shows a 20% increase in 'primary production' of phytoplanckton - the tiny creatures that make up the lowest level of the Arctic food chain.

However, species at the top of the food chain are coming under increasing pressure, scientists say. They note that there are "measurable changes linked with declines in sea ice at the top of the food chain, [including] marine mammals like walruses, whales, and polar bears." Polar Bear populations, which many view as the symbol of environmental change in the region, saw 7 of 19 population groups apparently declining in number, with trends in two of those linked to reductions in sea ice, which the bears use as a hunting platform.

The effects of the changes in sea ice are not limited to the oceans. A study by Bhatt et al., suggests that increased plant growth or 'greening' of the region over the last thirty years is closely associated with a reduction of sea ice close to the coast, as well as the generally warmer temperatures. Temperatures in the Arctic are two or more times greater than those observed at lower latitudes. This year surface air temperatures over much of the ocean were around 1.5 degrees Celsius greater than the 1981‐2010 average.

This has also contributed to record high 2011 temperatures across sampling sites which measure the temperature of the frozen ground in the region - the permafrost.

According to NOAA's summary of the science, record‐setting changes are occurring throughout the Arctic environmental system. Given projections of continued warming they fully expect these changes to continue in years to come, with increasing impacts.

The report card and more information, is available here.
Email Share to Facebook Stumble It
blog comments powered by Disqus