A 4,000-year-old, 72-square-mile natural structure in Canada’s Arctic known as the Milne Ice Shelf lost two icebergs at the end of July, one of which was the size of Manhattan, the Associated Press reported. Scientists have said that it is Canada‘s last intact ice shelf to collapse and they are unequivocal that climate change is to blame.
The collapse of ice shelves and the loss of ice in the Arctic region (which covers Canada, Russia, America, Iceland, and a few other European countries) overall has long been a concern for researchers who note that decreasing Arctic ice contributes to sea-level rise, changes in the jet stream and a loss of biodiversity.
The Milne Ice Shelf Collapsed In Just Days, Scientists Say
Canada’s Milne Ice Shelf had sustained “numerous fractures” over since 2008, according to CBS News, so its collapse was inevitable. Few predicted that it would be as large and occur as quickly as it did, however.
Adrienne White, an analyst for the Canadian Ice Service, told the Associated Press that the ice shelf, which is located on the northwestern edge of Ellesmere Island, lost 43% of its mass in just two days, around July 30 and 31. Two large icebergs – one 21 square miles, the other 7 square miles and both 230-260 feet thick – floated away as the Milne Ice Shelf was reduced from 72-square miles to just 41 square miles.
CBS News reported that there Ellesmere Island, which once boasted a continuous, coastline of ice shelves in Nunavut, has experienced major ice shelf losses in 2003, 2005, 2008, 2011 and 2012. The Guardian reported that this summer, Ellesmere Island had already lost its two St. Patrick Bay ice caps.
Jeff Berardelli, a CBS News meteorologist and climate specialist, said human-caused climate change has affected the Arctic at a pace far faster than mitigation efforts:
The Arctic is warming at 3 times the average of the globe because of human-caused climate change … and as a result, the landscape of the Arctic is changing at a staggering pace. We are running out (of) time to limit the damage from climate change.
The loss not only impacted the climate but also those researching it. Carleton University’s Derek Mueller, who is a professor and glaciologist, has been studying the Milne Ice Shelf for more than a decade. He told The Globe And Mail that he estimates he and others lost $90,000 in equipment, including sensors and instruments from the University of California-Davis.
Mueller said that he’s just glad no one was out in the field when it happened, due to the coronavirus pandemic.
What Is An Ice Shelf & Why Do They Matter?
Ice shelves, as defined by the National Snow and Ice Data Center (NSIDC), are “permanent floating sheets of ice that connect to a landmass.” They are formed when ice flows from land onto cold waters or other ice masses, such as glacial ice. Over the four seasons, icebergs typically calve off edges in warm weather and receive more ice in cold weather, maintaining a general balance of the level of ice.
However, more recently, warmer Arctic air has caused trickling water to deeply perforate the shelf overtime while warm water underneath has failed to reinforce the ice’s connection; this leads ice shelves to break off and collapse. The collapses, combined with high temperatures, have contributed to an overall loss of ice in the Arctic. Satellites from the National Aeronautics and Space Administration (NASA) have captured a consistent loss of ice in the Arctic, which has experienced both ice loss and substantial thinning.
Ice shelf collapses, the NSIDC says, can directly contribute to sea-level rise: “If an ice shelf collapses, the backpressure disappears. The glaciers that fed into the ice shelf speed up, flowing more quickly out to sea. Glaciers and ice sheets rest on land, so once they flow into the ocean, they contribute to sea-level rise.”
Arctic sea ice reached its annual low last year on September 18, 2019, according to NASA, which was also described as the second-lowest annual amount.
According to the National Oceanic & Atmospheric Administration’s Geophysical Fluid Dynamics Laboratory, ice sheet dynamics play a vital role in climate stability:
The present-day ice sheets contain the equivalent of about 65 meters of global sea-level rise, locked in the form of ice. Consequently, even relatively minor changes in the imbalance of the ice sheets have global significance. Two decades of satellite measurements in Greenland and Antarctica reveal snapshots of ongoing ice-sheet changes, which indicate potential significant sea-level rise over the next centuries.
What Could Higher Arctic Temps Mean Globally?
Although most have heard of global warming, few are aware of Arctic amplification, which NASA says describes how, “Temperatures have increased about twice as fast in the Arctic as in the mid-latitudes.” University of Ottawa glaciology professor Luke Copland told the Associated Press that in addition to that phenomenon, that region had been experiencing temperatures 9 degrees (5 degrees Celsius) warmer than the thirty years between 1980-2010 since May.
Siberia, for example, was once infamous for its bone-chilling winters but has recently been reporting record heat and wildfires.
Although the cause of this phenomenon is varied, one of the main reasons for Arctic amplification, according to NASA, is “albedo,” or “The ratio of the outgoing solar radiation reflected by an object to the incoming solar radiation incident upon it.” Ice tends to be white and therefore reflective while the oceans absorb more heat, so ice increases albedo; the less albedo, the more heat the surface of the earth absorbs instead of reflecting back into space.
Why does this matter? Researchers have connected Arctic amplification to wetter and stronger storms like Hurricane Sandy and they are using computerized and downscaled general circulation models to see if more conclusive evidence of this connection can be found.
All evidence suggests that the Arctic is not done shedding its shelves; according to Mark Serreze, the director of Colorado’s National Snow and Ice Data Center (NSIDC), Ellesmere’s two ice caps Murray and Simmons have been contracting and will likely be gone in a decade.
Losing more ice shelves could mean a global sea-level rise as water, stored vertically in the form of a solid, melts and flows – by way of the oceans – to the sea; such sea-level rise could have devastating impacts for coastal cities around the world, some of which are already shrinking. The loss of ice shelves could also mean a serious disruption to Arctic ecosystems and biodiversity; The Conservation of Arctic Flora and Fauna (CAFF) predicts that 30% of polar bears and more than half of wetlands in the Arctic and Sub-Arctic could be negatively impacted by climate change at the current rate.
The Globe And Mail described the loss of Milne as “a point of no return for a geographic feature that was once a hallmark of Canada’s High Arctic.” Dr. Mueller agreed, saying, “These are rare environments that we’ll never get back. We can’t change the climate fast enough to save them … but, if we can mitigate climate change, we could save other environments or slow down the speed of change.”