Three Record-breaking Summers Reveal “Critical Transition” for Antarctic Sea Ice

NSIDC: News & Analysis and Journal of Climate, 6 March 2024 For the third summer in a row, Antarctic sea ice coverage has dropped below two million square kilometers, a threshold which had not been breached since satellite records started in the 1980s. A new study labels these increasingly intense and long-lasting extreme events as […]

COP28 Video of the Week: “What the Extreme 2023 Sea Ice Minimum Tells Us About Antarctica’s Future”

Last year, Antarctic sea ice reached its lowest summer area since satellite records began, followed by a record-low winter sea ice maximum. This COP28 session provided an expert briefing on the global climate and ecosystem implications of 2023’s Antarctic sea ice observations, framing the year in comparison to future 1.5°C and 2°C scenario projections. Dr. […]

Widespread West Antarctic Retreat Began Already in 1940s

Proceedings of the National Academy of Sciences, 26 February 2024 An extreme El Niño warming in the 1940s triggered dramatic thinning and retreat of the massive Thwaites and Pine Island glaciers in West Antarctica, sending them into a sustained period of ice loss from which they did not recover, even when cooler temperatures later ensued. […]

COP28 Video of the Week: “Melting Ice Shelves Today Could Lead to the Collapse of West Antarctica”

Today’s temperatures have already locked in an unavoidable increase in West Antarctic ice shelf melting and rapid ocean warming, of approximately triple the historical rate through the end of the century. However, if global temperatures remain below the lower 1.5°C Paris limit, rates of ice shelf melting start to slow by 2100, suggesting that further […]

Only Low Emissions Can Protect Even Best-case Antarctic MPAs from Severe Ocean Acidification

Nature Communications, 4 January 2024 Only the lowest emissions scenarios (SSP1-2.6) with rapid and aggressive fossil fuel reductions can prevent “severe” acidification in the Southern Ocean, while even intermediate scenarios (SSP 2-4.5 and above) will expose ecosystems along the Antarctic continental shelves to increasingly hazardous conditions from surface to seafloor. Plankton at the base of […]

Antarctic Ice Shelves Melting Away from Stabilizing Seafloor Anchors

Nature, 21 February 2024 Rising temperatures have caused the disappearance of many “pinning points” which anchor ice shelves to the seafloor around West Antarctica and regions of East Antarctica over the past five decades. Ice shelf pinning points are fundamental to ice sheet stability, serving as buttresses that slow the flow of ice into the […]

Potential Physical Early Warning Signs of Atlantic Ocean Circulation Collapse

Science Advances, 9 February 2024 This paper identifies early warning signs for collapse of the AMOC (Atlantic Meridional Overturning Circulation). Authors definitively concluded that sudden AMOC collapse is no longer a theoretical concept for the global climate system, and noted that several of the physical ocean changes expected ahead of collapse have already been observed […]

COP28 Video of the Week: “Antarctic and Southern Ocean Ecosystems Under Severe Threat from Climate Change”

Climate change poses a severe threat to Antarctic and Southern Ocean ecosystems, from sea ice loss to warming waters and irreversible ocean acidification. This side event summarized the dramatic changes already occurring in polar oceans today, and outlined the global consequences of continued fossil fuel emissions. Leading scientists explained the necessary policy-level action required to […]

Past Warming Triggered Rapid Runaway Ice Loss in West Antarctica

Nature Geoscience, 8 February 2024 Scientists have uncovered for the first time direct evidence that the West Antarctic Ice Sheet dramatically thinned during a warm period at the end of the Last Ice Age, revealing how quickly this region could experience widespread ice loss if temperatures continue to rise as a result of today’s fossil […]

Short-term Extreme Events Essential in Predicting Future Sea Level Rise

Nature Reviews Earth & Environment, 8 February 2024 This review paper brought together an international team of 29 ice sheet experts to outline a path forward in improving future sea-level rise projections, with a focus on the long-lasting impacts of “short-term” extreme events such as heatwaves and atmospheric rivers. Short-term (i.e. daily to decadal) changes […]

Video of the Week: “Causes and Impacts of the March 2022 Extreme Heat Event in East Antarctica”

Following up on two companion papers printed in the Journal of Climate last week, this presentation by lead author Dr. Jonathan Wille decodes the record-busting March 2022 East Antarctica heat wave, including its impact on the Antarctic ice sheet. This extreme heat event saw numerous March temperature records broken, with unprecedented coastal rain and melting […]

Tropical Weather Directly Linked to Extreme Heat Event in East Antarctica

Journal of Climate, 1 February 2024 A team of five dozen scientists from fourteen countries unraveled the dynamics and impacts of the March 2022 record-shattering heat wave in East Antarctica. This extreme heat event raised temperatures in East Antarctica to an unprecedented +30-40°C above average, breaking not only March records for much of the continent, […]

Atmospheric River Creates Record-high Temperatures and Surface Melt in Antarctic Peninsula

NPJ Climate and Atmospheric Science, 4 December 2023 A similar atmospheric river swept intense heat and rainfall across the Antarctic Peninsula in February 2022, setting record-high surface melt compared to the previous four decades. The warm band of subtropical moisture directly hit the northwestern and northern side of the Peninsula. The eastern Peninsula then dramatically […]

COP28 Video of Week: “Climate Change Increases Antarctica’s Vulnerability to Extreme Events”

This side event features Dr. Jonathan Wille, ETH Zurich, lead author of the two companion papers summarized above. He volunteered at the COP28 Cryosphere Pavilion as part of our Early Career Scientists Program, sharing the latest scientific findings with policy makers. He organized this event with Dr. Martin Siegert, Deputy Vice Chancellor (Cornwall) at the […]

Record Low Snowfall Sounds Alarm for Water Security in the Hindu Kush Himalaya

News Briefing: 26 January 2024 Mirroring the “snow drought” that struck western North America, mountains across the Hindu Kush Himalaya (HKH) have similarly bare peaks this winter due to extremely low snowfall since October. Farmers throughout the region, especially in snow-fed downstream regions of India and Bangladesh, are raising the alarm that continued low mountain […]