The Arctic Ocean may be free of summer sea-ice as soon as sometime this decade, according to a new report from NOAA. As the report notes, it isn’t a question of if the Arctic will have ice-free summers, it’s simply when. And as of right now, NOAA’s projections say that it is very possible within the next decade or two, and extremely likely by the year 2050.
The Arctic is currently undergoing some vast and abrupt changes: rapid sea-ice melt, rapidly rising temperatures (above the global average rise), the destabilization of frozen methane (powerful greenhouse gas) stores currently locked in the permafrost and ocean floor, rapid Arctic greening, and the opening up of economically significant oil and gas stores, along with faster transportation routes through the Arctic.
How fast the summer sea-ice melts will have a lot to do with how rapidly these fossil fuel fields become available for exploitation. And how fast any potential conflicts associated with them will occur.
“Rapid Arctic sea ice loss is probably the most visible indicator of global climate change; it leads to shifts in ecosystems and economic access, and potentially impacts weather throughout the northern hemisphere,” said James Overland, a researcher at NOAA’s Pacific Marine Environmental Laboratory. “Increased physical understanding of rapid Arctic climate shifts and improved models are needed that give a more detailed picture and timing of what to expect so we can better prepare and adapt to such changes. Early loss of Arctic sea ice gives immediacy to the issue of climate change.”
“There is no one perfect way to predict summer sea ice loss in the Arctic,” said Muyin Wang of the NOAA Joint Institute for the Study of Atmosphere and Ocean at the University of Washington. “So we looked at three approaches that result in widely different dates, but all three suggest nearly sea ice-free summers in the Arctic before the middle of this century.”
The researchers emphasize that the wording “nearly ice free” is important, as some ice banks are likely to remain on the Northern edges of the Canadian Archipelago and Greenland.
The first of the three approaches is named the “trendsetters” approach, it relies on observed sea ice trends. These trends show that total Arctic decreased rapidly over the past decade. By projecting these trends into the future, a nearly sea ice-free Arctic appears to be the case by the year 2020.
The second approach, named the “stochasters” approach, “is based on assuming future multiple, but random in time, large sea ice loss events such as those that occurred in 2007 and 2012. This method estimates it would take several more events to reach a nearly sea ice-free state in the summer. Using the likelihood of such events, this approach suggests a nearly sea ice-free Arctic by about 2030 but with large uncertainty in timing.”
The third approach, dubbed the “modelers” approach, “is based on using the large collection of global climate model results to predict atmosphere, ocean, land, and sea ice conditions over time. These models show the earliest possible loss of sea ice to be around 2040 as greenhouse gas concentrations increase and the Arctic warms. But the median timing of sea ice loss in these models is closer to 2060. There are several reasons to consider that this median timing of sea ice loss in these models may be too slow.”
“Some people may interpret this to mean that models are not useful. Quite the opposite,” said Overland. “Models are based on chemical and physical climate processes and we need better models for the Arctic as the importance of that region continues to grow.”
When all of the approaches are taken together, it becomes clear that the potential is still limited to sometime within the next 10-45 years. Making it very likely that an ice-free Arctic will be the norm by the year 2050, and a real possibility that the summer’s may be ice-free as soon as within the next decade.
The new research was recently published in the American Geophysical Union publication Geophysical Research Letters.