A new report which was presented in Copenhagen this week has once again focused the spotlight on the speed with which the Arctic is being affected by the current global warming.
Margareta Johansson, from Lund University, is one of the researchers behind the report, and together with Terry Callaghan, a researcher at the Royal Swedish Academy of Sciences, edited the two chapters on snow and permafrost. Specifically, they listed nine different feedback effects currently being seen in the Arctic.
“The changes we see are dramatic. And they are not coincidental. The trends are unequivocal and deviate from the norm when compared with a longer term perspective,” Johansson says.
The report focused on several aspects of the Arctic that were being affected by global warming, and went over much of the information we have reported over the past few years.
- The last five years have been the warmest since 1880 when monitoring began
- Tree ring data suggest that the summer temperatures over the past few decades have been the highest in 2000 years
- Snow cover in May and June has decrease by close to 20%
- The winter season in the Arctic has been shortened by almost two weeks
- There is worry about the decrease in snow and ice cover in the Arctic that will decrease the amount of solar radiation reflected back out into the atmosphere
- Warming is only expected to continue
- Sea level rise by 2100 is expected to be between 0.9 and 1.6 metres, approximately twice what was predicted by the UN panel on climate change
There were several interesting parts of the report which bear repeating in a non-bullet point form, however.
Concern still radiates about the levels of carbon currently stored in the Arctic permafrost.
“Our data shows that there is significantly more than previously thought. There is approximately double the amount of carbon in the permafrost as there is in the atmosphere today,” says Johansson.
Scientists believe that there is a good chance this carbon will re-enter the atmosphere as the permafrost melts and the carbon is “unlocked” from its deep freeze.
“But it is also possible that the vegetation which will be able to grow when the ground thaws will absorb the carbon dioxide. We still know very little about this. With the knowledge we have today we cannot say for sure whether the thawing tundra will absorb or produce more greenhouse gases in the future,” says Johansson.
The report “Impacts of climate change on snow, water, ice and permafrost in the Arctic” has been compiled by close to 200 polar researchers, and was organised by the Arctic Council’s Arctic Monitoring and Assessment Programme.
“It is clear that great changes are at hand. It is all happening in the Arctic right now. And what is happening there affects us all,” says Johansson.