With presidential politics dominating much of the news coverage last week, along with the D.C. area thunderstorms and the heat, there were several climate change science news items that may have slipped past your Doppler 9000.
First up was another sobering assessment of Arctic sea ice cover. The National Snow and Ice Data Center (NSIDC) announced on June 3 that the Arctic sea ice is "on track for extreme melt" this summer. Last year Arctic sea ice set a new record low at the end of the melt season, when the Northwest Passage was largely ice free.
As I wrote on May 19, this year the sea ice cover is especially vulnerable due to the prevalence of seasonal ice, which is thinner than the multi-year ice that typically survives the melt season. The problem is that in recent years much of the multi-year ice has melted, leaving only the seasonal ice left to face the punishing Arctic summer sun.
Since my article appeared, data has come in indicating that the ice is already melting at a fast rate. According to Walt Meir, a research scientist at the NSIDC, trends observed in May indicate that the sea ice is on track to melt significantly again, although he said the actual extent of the melting depends on numerous factors. Last year, he said, there was "a perfect storm" of ocean and atmospheric conditions that combined to set the record. He put the odds of setting a new record low this year at about 50/50.
"It's definitely going to be a very low year," Meier said in a telephone interview.
The NSIDC's June 3rd update noted the appearance of several "polynyas" in the ice pack. According to the center, polynyas (which sound like the title of a Russian submarine in a Cold War movie) are defined as "irregularly shaped areas of persistent open water that are sustained by winds or ocean heat." Currently there are large coastal polynyas off of the Alaskan coast, in Baffin Bay, and near the Canadian Archipelago.
Polynyas can form from upwelling of warm water, or from persistent offshore winds that push sea ice away from the coast and prevent new ice from taking hold in that area, Meier said.
Meier said the presence of polynyas is not unusual, since they typically are seen in some areas at this time of year. However, they are more numerous now than usually occur at this time of year, and some are much larger than normal. For example, the Baffin Bay polynya, which is a normal occurrence in May, is close to reaching a record size. Much above normal temperatures in the Baffin Bay region during May might have contributed to the large polynya formation.
Meier said these areas of open water might be related to the prevalence of young ice, since it is more prone to breaking up under stress than older, thicker ice. Polynyas are important to keep an eye on because the open water absorbs more heat from the sun than ice cover does, thereby warming up faster and melting the ice along its edges. "That can speed up the melt," Meier said.
Rain forest destruction also made news last week, with the release of a study that used satellite imagery to estimate the loss of rain forest in ecologically rich Papua New Guinea. The study, which claimed to be the first comprehensive accounting of that nation's rain forests, found that the country's total forest cover has been declining at the alarmingly fast rate of about 1,400 square miles annually, or about 1.4 percent of the country's total forest cover per year. According to the New York Times, that would mean that if this rate continues, by 2021 more than 80 percent of Papua New Guinea's accessible forest would be badly degraded or cleared.
The issue of rain forest destruction is of critical importance for policy makers who are trying to reduce the world's greenhouse gas emissions. The rain forests act as a giant carbon sink without which levels of carbon dioxide, a major greenhouse gas, would be significantly higher. Because of this, countries such as Papua New Guinea are seeking to be compensated by the international community to keep their forests intact, but thus far they have not received funding on a scale that would compete with the economic incentives for cutting down forests for logging and agriculture.
In the introduction to the study, Belden Namah, Papua New Guinea's forests minister, stated that time is still left for trends to be reversed. "Over the past decades we have imagined that our forests are limitless - perhaps the rapid modernization that has occurred in PNG has made us reticent to accept the notions of scarcity - perhaps we have been too focused on local developments to see the big picture," Namah wrote. "Regardless, if this report is the bitter pill that we need to swallow to ensure that we maintain our forests into the foreseeable future, so be it."
The journal Philosophical Transactions of the Royal Society devoted its May issue to covering rain forest destruction in a different part of the world, the Amazon. The articles explore the links between the loss of forests and regional climate change, noting the potential for regional drought to develop in the area due to a combination of climate change and habitat destruction.
The leader of the small Pacific island nation of Kiribati warned the international community last week that his country may already be doomed due to climate change-related increases in sea level.
"We may be beyond redemption, we may be at the point of no return where the emissions in the atmosphere will carry on to contribute to climate change to produce a sea-level change that in time our small low-lying islands will be submerged," he said, according to an article by the AFP.
And finally, on a lighter note I'd like to take a moment to recognize the poor Senate clerks who had to read the entire text of a climate change bill in the Senate in the midst of the tempests that bore down on Washington last Wednesday. It may have been one of the worst days on the job for them, but it was the best thing that could have happened for sales of my upcoming seven-disk compilation of spoken word legislation.