Freshwater Discharge from Antarctica Shows Major Impacts on Future Climate

Science Advances, September 23 Under moderate and high emissions scenarios, the discharge of vast amounts of meltwater from the Antarctic Ice Sheet into the Southern Ocean could affect ocean currents and regional/global climate patterns due to impacts on the overturning ocean circulation.  The faster the ice sheet melts, the more cold freshwater flows into the […]

New Higher Estimates of Ice Loss from Greenland and Antarctica with High Emissions

The Cryosphere, September 17 Sea-level rise from the Greenland and Antarctic ice sheets alone could be 39 cm higher by 2100 than previously estimated under high emissions scenarios. These new estimates come from a large international effort comprising more than 30 different institutions and 60 leading ocean, climate and ice-sheet scientists; and are based on […]

Rising Temperatures Lead to Irreversible Ice Loss and Sea-level Rise From Antarctica

Nature, September 23 The rate and scale of ice loss from Antarctica will increase as temperatures exceed 2°C, according to new modeling from the Potsdam Institute.  At global warming up to 2°C above pre-industrial, Antarctica would lose enough ice mass to increase global sea-levels by 1.3 m per each degree of warming.  From 2°C to […]

Loss of Snow Cover on Svalbard Glaciers Accelerated Loss Since the mid-1980s.

Nature Communications, September 14 Most of Svalbard’s glaciers and ice caps have lost the porous snow layer that previously protected them from yearly temperature fluctuations. This snow layer was lost below a critical altitude of 450 meters already in the 1980s, which rendered 60% of Svalbard’s ice highly vulnerable to further warming; starting a period […]

Antarctica without Ice Shelves Leads to Rapid Multi-Meter Sea Level Rise

Journal of Glaciology, September 14 Collapse of ice shelves neighbouring the Antarctic Ice Sheet has the potential to contribute 1 to 12 meters of sea level rise over the next 500 years, with 1.9 to 5 meters generated within 500 years by the collapse of ice shelves adjoining the West Antarctic Ice Sheet alone. Such […]

WAIS Ice Shelves Show Early Signs of Irreversible Disintegration

PNAS, September 14 Extensive open fractures have developed in the ice shelves of the Pine Island and Thwaites glaciers in the West Antarctic Ice Sheet, potentially priming them for future collapse. No such crevasses existed at the beginning of satellite records in 1997, with rapidly growing crevasse-damaged areas by 2019, accelerating since 2016.  These damaged […]

New Destabilizing Arctic Under High Emissions Scenario

Nature Climate Change, September 14 The Arctic is at high risk of undergoing a rapid state change away from a cryosphere-dominated system, leading researchers to call on governments urgently to reduce greenhouse gas emissions to avoid losing the its stabilizing role on the global climate system.  Under current high emissions scenarios, using the new CMIP5 […]

Warmer Atlantic and More Storms Decrease Sea Ice North of Svalbard

Journal of Geophysical Research, July 11 On the other side of the Arctic, an earlier study this summer found that winter storms and warm near‐surface Atlantic water appear directly responsible for winter sea ice loss in the Whalers Bay area north of Svalbard.  The amount of heat transported from the Atlantic Ocean, and storm frequency both […]

2018 Bering Sea Winter Sea Ice Lowest in At Least 5500 Years

Science Advances, September 2 Summer sea ice minimums receive the most attention; but Arctic sea ice has been declining year-round, and new reconstructions place the 2018 winter maximum in the Bering Sea as the lowest in at least 5500 years.  The 2018 and 2019 maximums were also 60-70% lower than the averages recorded since consistent […]

Large Reduction in Glaciers Under High Emissions Scenario in Central Himalayas

Journal of Glaciology, August 26 Up to 85% of the glaciers found in the Koshi River Basin could disappear by 2100 under the highest emission scenarios (RCP8.5). The Koshi River, a major tributary of the Ganges has a 50,000 km2 basin (the size of Costa Rica).  Over 5% is covered by glaciers, and spreads across India, Nepal, […]

Huge Pathways of Warm Water Found Under Major Antarctic Glacier

New maps collected under the floating tongue of Thwaites Glacier and further offshore reveal deep (> 1000 m) and wide (> 20,000 m) channels that guide warm ocean water under the ice, accelerating melt that eventually may lead to collapse. Thwaites, part of the West Antarctic Ice Sheet (WAIS) is the size of Great Britain, […]

2020 Arctic Fires Already One-third Higher Than 2019 Record High

Copernicus Atmosphere Monitoring Service, September 3 Arctic fire emissions – those directly caused by humans, as well as those from natural phenomena such as lightning strikes – already are one-third higher than the 2019 total, which itself broke the previous record.  The CO2 released from these fires through the end of August totalled around 244 […]

Majority of Antarctic Ice Shelves Sensitive to Meltwater Fracturing

Nature, August 26 Antarctic ice shelves – floating ice in contact with land ice – are both critical to maintaining ice sheet stability, and vulnerable to catastrophic fracturing from meltwater entering crevasses. Hydro-fracturing occurs when surface meltwater flows into and deepens pre-existing fractures, and is a potential mechanism driving sudden ice shelf collapse, as occurred with […]

Earlier Spring Rain on Arctic Sea Ice Accelerates Loss

The Cryosphere, August 28 Rain events on some portions of the Arctic Ocean have occurred nearly 4-6 days earlier for each recent decade, accelerating the onset of sea ice melt in the Pacific sector of the Arctic Ocean, and in the Eurasian Marginal seas above Siberia. This study combined limited field observations at Arctic coastal […]

Rapid Worldwide Growth in Glacial Lakes and Risk of Outburst Floods

Nature Climate Change, August 31 The global volume of glacier lakes increased 48% between 1990 and 2018, to 156.5 km3, a volume that would cover the country of Liechtenstein by a lake 1 km deep. Glacial lakes are bodies of water fed by a glacier’s meltwater, and subject to sudden outburst events that unexpectedly can […]