Arctic Ice at Low Point Compared to Recent Geologic History
by Pam Frost Gorder
Leonid Polyak
Less ice covers the Arctic today than at any time in recent geologic history.
That’s the conclusion of an international group of researchers, who have compiled the first comprehensive history of Arctic ice.
For decades, scientists have strived to collect sediment cores from the difficult-to-access Arctic Ocean floor, to discover what the Arctic was like in the past. Their most recent goal: to bring a long-term perspective to the ice loss we see today.
Now, in an upcoming issue of Quarternary Science Reviews, a team led by Ohio State University has re-examined the data from past and ongoing studies — nearly 300 in all — and combined them to form a big-picture view of the pole’s climate history stretching back millions of years.
“The ice loss that we see today — the ice loss that started in the early 20th Century and sped up during the last 30 years — appears to be unmatched over at least the last few thousand years,” said Leonid Polyak, a research scientist at Byrd Polar Research Center at Ohio State University. Polyak is lead author of the paper and a preceding report that he and his coauthors prepared for the U.S. Climate Change Science Program. (more…)
Arctic Sea Ice Extent Is Third Lowest on Record
Tom Wagner, NASA's cryosphere program manager, describes the shrinking of Arctic sea ice and the significance of the problem for the rest of the planet. (Jefferson Beck, NASA)
U.S. satellite measurements show Arctic sea ice extent in 2009 – the area of the Arctic Ocean covered by floating ice – was the third lowest since satellite measurements were first made in 1979. The ice area at minimum was an increase from the past two years, but still well below the average for the past 30 years.
Arctic sea ice reached its minimum extent around September 12, as shown in the image and video below/above. According to scientists affiliated with the National Snow and Ice Data Center (NSIDC), sea ice coverage dropped to 5.10 million square kilometers (1.97 million square miles) at its minimum. The ice cover was 970,000 square kilometers (370,000 square miles) greater than the record low of 2007 and 580,000 square kilometers (220,000 square miles) greater than 2008.
NSIDC is sponsored by several U.S. government agencies, including NASA. Ice data are derived from measurements made by U.S. Department of Defense and NASA satellites, with key work in interpreting the data and developing the 30-year history done by scientists at NASA’s Goddard Space Flight Center in Greenbelt, Md. (more…)
Airborne Expedition Chases Arctic Sea Ice Questions
CU-Boulder and NASA are teaming up this summer on a series of unmanned aircraft flights to study the receding Arctic sea ice and to better understand its life cycle and the long-term stability of the Arctic ice cover. (Image courtesy James Maslanik, University of Colorado)
A small NASA aircraft completed its first successful science flight Thursday in partnership with the University of Colorado at Boulder as part of an expedition to study the receding Arctic sea ice and improve understanding of its life cycle and the long-term stability of the Arctic ice cover. The mission continues through July 24.
NASA’s Characterization of Arctic Sea Ice Experiment, known as CASIE, began a series of unmanned aircraft system flights in coordination with satellites. Working with CU-Boulder and its research partners, NASA is using the remotely piloted aircraft to image thick, old slabs of ice as they drift from the Arctic Ocean south through the Fram Strait — which lies between Greenland and Svalbard, Norway — and into the North Atlantic Ocean. (more…)
Sea Ice at Lowest Point in 800 Years
There has never been so little sea ice in the area between Svalbard and Greenland in the last 800 years. (NASA/GSFC)
New research, which reconstructs the extent of ice in the sea between Greenland and Svalbard from the 13th century to the present indicates that there has never been so little sea ice as there is now. The research results from the Niels Bohr Institute, among others, are published in the scientific journal, Climate Dynamics.
There are of course neither satellite images nor instrumental records of the climate all the way back to the 13th century, but nature has its own ‘archive’ of the climate in both ice cores and the annual growth rings of trees and we humans have made records of a great many things over the years - such as observations in the log books of ships and in harbour records. Piece all of the information together and you get a picture of how much sea ice there has been throughout time. (more…)
Cuts in Greenhouse Gas Emissions Would Save Arctic Ice, Reduce Sea Level Rise
NCAR scientist Warren Washington, the lead author of study. (©UCAR, photo by Carlye Calvin.)
The threat of global warming can still be greatly diminished if nations cut emissions of heat-trapping greenhouse gases by 70 percent this century, according to a new analysis. While global temperatures would rise, the most dangerous potential aspects of climate change, including massive losses of Arctic sea ice and permafrost and significant sea level rise, could be partially avoided.
The study, led by scientists at the National Center for Atmospheric Research (NCAR), will be published next week in Geophysical Research Letters. It was funded by the Department of Energy and the National Science Foundation, NCAR’s sponsor. (more…)
Loading... 
