Greenland glacier thickening

Water temperatures in the vicinity of the glacier are now colder than they have been since the mid-1980s.

Direct quotes from an article published by NASA:

“NASA research shows that Jakobshavn Glacier, which has been Greenland’s fastest-flowing and fastest-thinning glacier for the last 20 years, has made an unexpected about-face. Jakobshavn is now flowing more slowly, thickening, and advancing toward the ocean instead of retreating farther inland.”

The researchers conclude that the about-face “occurred because an ocean current that brings water to the glacier’s ocean face grew much cooler in 2016. Water temperatures in the vicinity of the glacier are now colder than they have been since the mid-1980s.”

“In a study published (on March 19 of this year) in Nature Geoscience, Ala Khazendar of NASA’s Jet Propulsion Laboratory in Pasadena, California, and colleagues report the change in Jakobshavn’s behavior and trace the source of the cooler water to the North Atlantic Ocean more than 600 miles (966 kilometers) south of the glacier. The research is based on data from NASA’s Oceans Melting Greenland (OMG) mission and other observations.”

“The scientists were so shocked to find the change, Khazendar said: “At first we didn’t believe it. We had pretty much assumed that Jakobshavn would just keep going on as it had over the last 20 years.” However, the OMG mission has recorded cold water near Jakobshavn for three years in a row.”

“The researchers suspect the cold water was set in motion by a climate pattern called the North Atlantic Oscillation (NAO), which causes the northern Atlantic Ocean to switch slowly between warm and cold every five to 20 years. The climate pattern settled into a new phase recently, cooling the Atlantic in general. This change was accompanied by some extra cooling in 2016 of the waters along Greenland’s southwest coast, which flowed up the west coast, eventually reaching Jakobshavn.”

“The research team combined earlier data on ocean temperature with data from the OMG mission, which has measured ocean temperature and salinity around the entire island for the last three summers. They found that in 2016, water in Jakobshavn’s fjord cooled to temperatures not seen since the 1980s.”

“Tracing the origin of the cold waters in front of Jakobshavn was a challenge,” explained Ian Fenty of JPL, a co-author of the study. “There are enough observations to see the cooling but not really enough to figure out where it came from.” Using an ocean model called Estimating the Circulation and Climate of the Ocean (ECCO) to help fill in the gaps, the team traced the cool water upstream (toward the south) to a current that carries water around the southern tip of Greenland and northward along its west coast. In 2016, the water in this current cooled by more than 2.7 degrees Fahrenheit (1.5 degrees Celsius).

“Although the last few winters were relatively mild in Greenland itself, they were much colder and windier than usual over the North Atlantic Ocean. The cold weather coincided with the switch in the NAO climate pattern. Under the influence of this change, the Atlantic Ocean near Greenland cooled by about 0.5 degrees Fahrenheit (1 degree Celsius) between 2013 and 2016. These generally cooler conditions set the stage for the rapid cooling of the ocean current in southwest Greenland in early 2016. The cooler waters arrived near Jakobshavn that summer, at the same time that Jakobshavn slowed dramatically.”

“The team suspects that both the widespread Atlantic cooling and the dramatic cooling of the waters that reached the glacier were driven by the shift in the NAO.”

It’s a cycle, it’s a cycle, it’s a cycle

The article goes on to insist that, even though the glacier is thickening and advancing, it “is still adding to global sea level rise.” Really? Even though it is thickening? 

The article also insists that “the cooling is temporary and warm waters will return when the NAO shifts to a warm phase once again.”

In other words, the thickening and advancing is being caused by a natural cycle (the NAO), and the return of warm waters will be caused by the same natural cycle (the NAO). A NATURAL cycle.

I’ve said it before and I’ll say it again: It’s a cycle, it’s a cycle, it’s a cycle.

Is it possible that humans are not the culprits after all?.  

https://www.jpl.nasa.gov/news/news.php?feature=7356

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August 5, 2019 at 11:54AM

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