This sketch of the St. Patrick Bay ice caps, taken from The Cryosphere 2017 article, is based on aerial photographs from August 1959, GPS surveys conducted in August 2001 and August 2014 and 2015 from the Emission Radiometer and NASA Advanced Thermal Reflection. (ASTER). It shows the area of the St. Patrick’s Bay ice sheets in 1959, 2001, 2014 and 2015. The ice sheets were noticeably smaller in 2015 than in previous years. Credit: University of Colorado at Boulder
The St. Patrick Bay ice sheets on the Hazen Plateau on the northeast island of Ellesmere in Nunavut, Canada have disappeared, according to NASA satellite imagery. Scientists and colleagues at the National Snow and Ice Data Center (NSIDC) predicted through a 2017 article in Cryosphere that the ice sheets would melt completely within the next five years, and recent images from NASA’s Advanced Earth Emission and Reflection Radiometer (ASTER) have confirmed that this prediction was accurate.
Mark Serreze, director of NSIDC, Distinguished Professor of Geography at the University of Colorado Boulder, and lead author of the article, first stepped on the St. Patrick Bay ice sheets in 1982 as a young graduate student. He visited the polar ice caps with his adviser, Ray Bradley of the University of Massachusetts.
“When I visited those ice sheets the first time, they seemed like such a permanent element of the landscape,” Serreze said. “Watching them die in less than 40 years leaves me speechless.”
In 2017, scientists compared ASTER’s satellite data from July 2015 to vertical aerial photographs taken in August 1959. They found that between 1959 and 2015, ice sheets had shrunk to just five percent of their previous area, and were markedly reduced between 2014 and 2015 in response to the especially hot summer in 2015. Ice sheets are absent from ASTER images taken on July 14, 2020.
The St. Patrick Bay ice sheets were half of a group of small ice sheets on the Hazen Plateau, which formed and probably peaked during the Little Ice Age, perhaps several centuries ago. The Murray and Simmons ice caps, which make up the second half of the Hazen Plateau ice caps, are at a higher elevation and therefore doing better, though scientists predict their disappearance. it is also imminent.
-
These satellite images from the NASA Advanced Terrestrial Reflection and Thermal Emission Radiometer (ASTER) show the location where the ice caps of St. Patrick’s Bay used to exist on the Hazen Plateau, on the northeast island of Ellesmere in Nunavut, Canada. The ice sheets were still intact in the photo on the left, taken in August 2015. From the photo on the right, taken in July 2020, the ice sheets have melted and no longer exist. Credit: Bruce Raup, NSIDC
-
This satellite image from the NASA Advanced Reflection Thermal Emission Radiometer (ASTER) dated August 4, 2015 shows the location of the St. Patrick’s Bay ice caps (in a blue circle). As of July 2020, satellite imagery shows that these ice sheets have disappeared. Credit: Bruce Raup, NSIDC
-
This NASA satellite image from July 14, 2020 shows where the ice caps of St. Patrick’s Bay (area surrounded by blue) were. As of July 2020, satellite imagery shows that these ice sheets have disappeared. Credit: Bruce Raup, NSIDC
“We have long known that as climate change takes hold, the effects would be especially pronounced in the Arctic,” Serreze said. “But the death of those two little caps that I once knew so well has made climate change very personal. All that remains are a few photographs and many memories.”
Insulin cost-sharing limits can help children and young adults with type 1 diabetes
Mark C. Serreze et al. Rapid waste from the polar caps of the Hazen Plateau on the northeast island of Ellesmere, Nunavut, Canada Cryosphere (2017) DOI: 10.5194 / tc-11-169-2017
Provided by the University of Colorado at Boulder
Citation: Canadian ice sheets disappear, confirming 2017 scientific prediction (2020, July 31) obtained on July 31, 2020 from https://phys.org/news/2020-07-canadian-ice-caps-scientific .html
This document is subject to copyright. Other than fair dealing for private research or study purposes, no part may be reproduced without written permission. The content is provided for informational purposes only.
