Search Results for: antarctic

Via: https://scitechdaily.com/antarcticas-astonishing-rebound-ice-sheet-grows-for-the-first-time-in-decades/ The Antarctic Ice Sheet (AIS) has historically lost mass, significantly contributing to sea-level rise, with intensified losses in West Antarctica and parts of East Antarctica, particularly from 2011–2020. However, between 2021 and 2023, driven by anomalous precipitation, the AIS experienced a record-breaking mass gain, even reversing trends in critical glacier basins like Totten, Moscow, Denman, and Vincennes Bay. Mass changes across the Antarctic ice sheet have been detected using satellite gravimetry, revealing significant instabilities in major glacier basins of East Antarctica as well as across the entire ice sheet. The Antarctic Ice Sheet (AIS) plays a major role in global sea-level rise. Since March 2002, the GRACE (Gravity Recovery and Climate Experiment) mission and its successor, GRACE-FO (GRACE Follow-On), have provided valuable data to monitor changes in ice mass across the AIS. Previous studies have consistently shown a long-term trend of mass loss, particularly in West Antarctica and the Antarctic Peninsula, while glaciers in East Antarctica appeared relatively stable. However, a recent study led by Dr. Wang and Prof. Shen at Tongji University has found a surprising shift: between 2021 and 2023, the AIS experienced a record-breaking increase in overall mass. Antarctic Ice Sheet mass change series (April 2002–December 2023) derived from GRACE/GRACE-FO satellite gravimetry. Ellipses highlight period-specific mass change rates, while the grey shadow indicates the data gap between missions. Credit: Science China Press Notably, four major glaciers in the Wilkes Land–Queen Mary Land region of East Antarctica reversed their previous pattern of accelerated mass loss from 2011 to 2020 and instead showed significant mass gain during the 2021 to 2023 period. Record-breaking mass gain over the Antarctic Ice Sheet From 2002 to 2010, the AIS has experienced a mass loss with a change rate of –73.79±56.27 Gt/yr, which nearly doubled to –142.06±56.12 Gt/yr for the period 2011–2020. This accelerated mass loss was primarily related to intensified mass depletion in West Antarctica and the WL-QML region of East Antarctica. However, a significant reversal occurred thereafter, driven by anomalous precipitation accumulation, the AIS gained mass at a rate of 107.79±74.90 Gt/yr between 2021 and 2023. Spatial distributions of mass change rates over the AIS and its regions for three sub-periods. Credit: Science China Press Correspondingly, the contribution of mass change over the AIS to global mean sea level rise was 0.20±0.16 mm/yr during 2002–2010 and 0.39±0.15 mm/yr during 2011–2020. In contrast, during 2021–2023, it exerted a negative contribution, offsetting global mean sea level rise at a rate of 0.30±0.21 mm/yr. Enhanced mass loss of the Totten, Moscow, Denman, and Vincennes Bay glacier basins, East Antarctica The four key glacier basins in WL-QML region, i.e., Totten, Moscow University, Denman, and Vincennes Bay, exhibited mass loss intensification with a rate of 47.64±8.14 Gt/yr during 2011-2020, compared to 2002-2010, with the loss area expanding inland. The researchers explained “this accelerated mass loss was primarily driven by two factors: surface mass reduction (contributing 72.53%) and increased ice discharge (27.47%).” Spatiotemporal patterns of mass change rates (2002–2020) for Totten, Moscow, Denman, and Vincennes Bay glacier basins. Gray box: rate differences (2011–2020 minus 2002–2010); light blue boxes: time series with epoch rates (elliptical markers), where the gray shadow denotes GRACE-GRACE-FO data gap. Credit: Science China Press Notably, the complete disintegration of these four glaciers could potentially trigger a global mean sea level rise exceeding 7 meters. Their pronounced ablation patterns already constitute a critical climate warning signal, warranting greater scientific attention to their stability. Reference: “Spatiotemporal mass change rate analysis from 2002 to 2023 over the Antarctic Ice Sheet and four glacier basins in Wilkes-Queen Mary Land” by Wei Wang, Yunzhong Shen, Qiujie Chen, Fengwei Wang and Yangkang Yu, 19 March 2025, Science China Earth Sciences. DOI: 10.1007/s11430-024-1517-1

https://www.livenowfox.com/news/antarctica-ice-sheet-growth By Austin Williams The Antarctic Ice Sheet gained mass between 2021 and 2023, a dramatic reversal from decades of loss. Four key glacier basins in East Antarctica showed significant growth due to increased snowfall. The mass gain briefly contributed to a decrease in global sea level rise, according to satellite data. A surprising shift is underway at the bottom of the world. After decades of contributing to rising sea levels, Antarctica’s massive ice sheet has started growing again — at least for now. A study published this week in Science China Earth Sciences finds that the Antarctic Ice Sheet (AIS) experienced a record-breaking mass gain between 2021 and 2023, largely due to anomalous increases in precipitation. The rebound is especially significant in East Antarctica, where four major glacier basins had previously shown signs of destabilization. Satellite data shows ice sheet mass increase Big picture view: Researchers from Tongji University and other institutions analyzed satellite gravimetry data from the GRACE and GRACE-FO missions, which measure variations in Earth’s gravity to detect changes in ice mass. They found that between 2011 and 2020, the AIS was losing ice at a rate of 142 gigatons per year. But between 2021 and 2023, the trend reversed, with the ice sheet gaining approximately 108 gigatons per year — a historic turnaround. That growth was enough to temporarily offset global sea level rise by about 0.3 millimeters per year during the same period. Key glacier basins showed the most dramatic shift The most notable gains were in East Antarctica’s Wilkes Land and Queen Mary Land region, including the Totten, Denman, Moscow University, and Vincennes Bay glacier basins. These glaciers had been losing mass at an accelerating rate from 2011 to 2020 — driven by surface melting and faster ice discharge into the ocean — but now appear to have partially recovered. Scientists warn, however, that this shift doesn’t mean the climate crisis is over. The gains were linked to unusual precipitation patterns, which may be temporary. What’s next: The Antarctic Ice Sheet holds more than half of the world’s fresh water. For decades, it’s been one of the largest contributors to sea level rise, alongside Greenland’s melting ice and thermal expansion of warming oceans. # Antarctica has 90% of the world‘s ice and it is completely stable and safe. The continent has no warming trend at all. https://t.co/W0kLzoURMN — Wei. Zhang (@WeiZhangAtmos) May 5, 2025

Antarctica Ice Growing Across Large Areas for at Least 85 Years, Aerial Photos Show From THE DAILY SCEPTIC by Chris Morrison Sensational new discoveries arising from long-forgotten early aerial photographs indicate that ice has remained stable and even grown slightly since the 1930s over a 2,000 km stretch of East Antarctica. In a recent paper published in Nature Communications, researchers from the University of Copenhagen came to their conclusions by tracking glacial movement in an area with as much ice as the Greenland ice sheet. The findings are unlikely to feature in narrative-driven mainstream media. The silence will probably replicate the response to another recent paper that found the ice shelves surrounding Antarctica grew in overall size from 2009-2019. The Copenhagen scientists examined hundreds of old aerial photographs taken for mapping work in 1937. The images were supplemented with a number of photographs taken in the 1950s and 1974 of the same area and a 3D computer reconstruction was produced. This allowed the researchers to examine the evolution of glaciers over a significant time period. In order to determine if recent trends exceed the scale of natural variability, long-term observations are said to be vital. “Compared to modern data, the ice flow speeds are unchanged. While some glaciers have thinned over shorter intermediate periods of 10-20 years, they have remained stable or grown slightly in the long term, indicating a system in balance,” it was noted. Actual long-term scientific observations will always beat media-friendly computer-modelled pseudoscientific opinions and alarm drummed up by short-term outliers. The authors note that using data from historical sources such as early photographs provides extensive coverage across large areas with detailed temporal and three-dimensional information. Geological evidence covers longer time scales with temporal uncertainties of thousands of years, while estimates from ice cores are generally very local and spatially confined. In Antarctica, it is pointed out, the scarcity of historical climate data makes climate reanalysis estimates before 1970 “largely uncertain”, while “observed trends cannot clearly be distinguished from natural variability”. Not that this stops mainstream activists such as Clive Cookson at the Financial Times who reacted to a recent two-year downward spike in Antarctica sea ice with the suggestion that the area faced a “catastrophic cascade of extreme environmental events… that will affect the climate around the world”. Of course a “system in balance” is the last thing a Net Zero-obsessed mainstream wants to hear about. The Antarctica Circumpolar Current is the strongest flow of water on the planet and on March 4th the BBC brought news that it was “at risk of failing”. New research is said to suggest that the current will be 20% slower within 25 years “as the world warms, with far reaching consequences for life on Earth”. Fresh ice melt water  is said to cause major changes in the density structure of the ocean, leading to a projected slowdown of the current. Inexplicably, the BBC report failed to note that the prediction was generated by a computer model which had been loaded with a ‘pathway’ that assumed global temperatures would rise up to 4°C within less than 80 years. The clickbait-searching scientists behind the findings observed the recent rapidly declining sea ice in Antarctica, but failed to report a more recent recovery. At the end of 2024, the extent of sea ice was roughly the same as the 1981 to 2010 average. According to the US-based National Snow and Ice Data Centre, “this provides a sharp illustration of the high variability of Antarctica sea ice extent”. And recent examination of earlier photographic evidence provides more insights, with early Nimbus weather satellite images revealing that the 2023 decline was similar to that seen in 1966. Regular readers of the Daily Sceptic will of course be aware that Antarctica is a difficult place to whip up climate panic, although it must be conceded that mainstream science and media have spared little effort in attempting to do so. Over the last seven decades there has been little or no warming over large areas of the continent. What warming there has been, on the west side, is directly on top of a large number of volcanoes. A recent paper from Singh and Polvani found that Antarctica sea ice “has modestly expanded, a finding that seems to confirm the work on the ice shelf increases between 2009-2019. Warming has been “nearly non-existent” over 70 years, state Singh and Polvani. According to NASA figures, the ice loss is 0.0005% a year. As an example of how humans cause the climate to warm by burning hydrocarbons and eating meat, Antarctica leaves a lot to be desired. Chris Morrison is the Daily Sceptic’s Environment Editor.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2024GL112235?campaign=woletoc#main1 Abstract Massive calving events result in significant instantaneous ice loss from Antarctica. The rarity and stochastic nature of these extreme events makes it difficult to understand their physical drivers, temporal trends, and future likelihood. To address this challenge, we turn to extreme value theory to investigate past trends in annual maxima iceberg area and assess the likelihood of high-magnitude calving events. We use 47 years of iceberg size from satellite observations. Our analysis reveals no upward trend in the surface area of the largest annual iceberg over this time frame. This finding suggests that extreme calving events such as the recent 2017 Larsen C iceberg, A68, are statistically unexceptional and that extreme calving events are not necessarily a consequence of climate change. Nevertheless, it is statistically possible for Antarctica to experience a calving event up to several times greater than any in the observational record. Key Points This study presents the first comprehensive analysis of Antarctica’s biggest icebergs in the observational record There is no upward trend in the surface area of Antarctica’s annual maximum iceberg between 1976 and 2023 A once in a century calving event would yield an iceberg surface area approximately the size of Switzerland #   Things just got tougher for climate alarmists. Remember when Iceberg A-68 calved off Antarctica's Larsen C Ice Shelf in the summer of 2017? The climate chicken littles blamed it on global warming. Well, a new study published in Geophysical Research Letters (GRL) casts… pic.twitter.com/SwzRgWWs2G — Chris Martz (@ChrisMartzWX) December 15, 2024

Early aerial expedition photos reveal 85 years of glacier growth and stability in East Antarctica

Published: 25 May 2024 – Mads Dømgaard,  Anders Schomacker,  Elisabeth Isaksson,  Romain Millan,  Flora Huiban,  Amaury Dehecq, Amanda Fleischer,  Geir Moholdt,  Jonas K. Andersen &  Anders A. Bjørk 

Nature Communications: Our results demonstrate that the stability and growth in ice elevations observed in terrestrial basins over the past few decades are part of a trend spanning at least a century, and highlight the importance of understanding long-term changes when interpreting current dynamics. … However, in Antarctica, the scarcity of historical climate data makes climate reanalysis estimates before the 1970s largely uncertain^10,23, and observed trends cannot clearly be distinguished from natural variability^24,25. 

Currently, the earliest ice-sheet wide mass balance estimates start in the late 1970s^3,6,7, and since then all the sub-regions examined in this study have exhibited either an overall mass gain or been relative unchanged.

…

Regardless of potential climatic changes, our results indicate that the glacier in Kemp and Mac Robertson Land and along Ingrid Christensen Coast, have accumulated mass during the past 85 years which inevitably have mitigated parts of the more recent mass loss from the marine basins in East Antarctica and the West Antarctic Ice Sheet (WAIS). This positive accumulation trend and positive mass balance is anticipated to persist as snowfall is expected to increase over the entire EAIS in the next century^54,55, and ice sheet modeling studies project positive mass balance estimates in all three sub-regions across all future RCP scenarios⁵⁶. Lastly, we determine frontal changes of 21 glaciers from 1937 to 2023 (Table S1 and Fig. S11). From the 85 years of observations, we find two distinct regional patterns; one of constant glacier surface elevations and one of ice thickening.