As part of this study, the potential sea-ice outlook generated by the general circulation model, as well as several features of polar bear life history, were placed into a larger network model.
The model can, for example, be used to examine the relationship between polar bears and their environment.
The results indicate that increased retention of sea-ice habitat because of greenhouse gas mitigation would allow polar bears to survive in greater numbers throughout this century, and in more areas of the Arctic, than would happen with no mitigation.
Amstrup divided the Arctic into four separate ecoregions according to the nature of ice typically found there.
The 2007 study showed a very high likelihood that polar bears would become extinct in two of those regions given current trends in greenhouse gas emissions.
"There's still a fairly high probability in both those regions that polar bears could disappear," Amstrup said.
"But with mitigation and aggressive management of hunting and other direct bear-human interactions, the probability of extinction would now be lower than the probability that polar bear numbers will simply be reduced.
"With mitigation, conditions for polar bears might even improve in the other two ecoregions. The benefit of mitigation to polar bears is substantial."
|Contact: Cheryl Dybas|
National Science Foundation