Animal and plant life set to increase in the Arctic
A group of scientists from the National Oceanography Centre in Southampton studied mud samples laid down in the Arctic during the late Cretaceous period between 99 and 65 million years ago, when it’s thought that high levels of carbon dioxide in the atmosphere caused the Arctic ice cap to melt during the summer and
refreeze in the winter.
The scientists found layers of tiny algae called diatoms in the mud, which appeared to be less plentiful in the winter than in summer, when their levels were so high that the area was as biologically rich as the Southern Ocean is today. Because diatoms are at the bottom of the food chain, if similar numbers reappear by 2030 – the year that, some scientists have predicted, the Arctic ice cap will completely melt during the summer – the algae should be able to support other larger animals too.
‘The outcome would depend on organisms at all levels of the food chain moving in to exploit this potential,’ Alan Kemp, who carried out the research with his colleagues, told New Scientist. ‘What is unpredictable is which species from elsewhere may migrate in to fill the new ecological niches.’
A separate study by scientists led by Eric Post, a biologist at Penn State University, has found that while some Arctic species, such as the ringed seal and caribou, are already suffering from warming temperatures, others, such as the red fox and winter moth, are moving into areas that were previously too cold for them.
Climate change is also having an effect on vegetation in the High Arctic. A study by geographer Greg Henry of the University of British Columbia shows that plant material has doubled – or in some places tripled – since he first recorded vegetation on Ellesmere Island in northern Canada in 1980.
November 2009
refreeze in the winter.
The scientists found layers of tiny algae called diatoms in the mud, which appeared to be less plentiful in the winter than in summer, when their levels were so high that the area was as biologically rich as the Southern Ocean is today. Because diatoms are at the bottom of the food chain, if similar numbers reappear by 2030 – the year that, some scientists have predicted, the Arctic ice cap will completely melt during the summer – the algae should be able to support other larger animals too.
‘The outcome would depend on organisms at all levels of the food chain moving in to exploit this potential,’ Alan Kemp, who carried out the research with his colleagues, told New Scientist. ‘What is unpredictable is which species from elsewhere may migrate in to fill the new ecological niches.’
A separate study by scientists led by Eric Post, a biologist at Penn State University, has found that while some Arctic species, such as the ringed seal and caribou, are already suffering from warming temperatures, others, such as the red fox and winter moth, are moving into areas that were previously too cold for them.
Climate change is also having an effect on vegetation in the High Arctic. A study by geographer Greg Henry of the University of British Columbia shows that plant material has doubled – or in some places tripled – since he first recorded vegetation on Ellesmere Island in northern Canada in 1980.
November 2009
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