December 23, 2024

Melting of the Antarctic Ice Sheet Could Cause 5-Meter Rise in Sea Levels by the End of the Millennium

Simulated mass loss of the Antarctic ice sheet from 1990 until 3000 revealed as sea-level contribution: Fourteen experiments for the unabated warming pathway (RCP8.5, SSP5-8.5), 3 experiments for the decreased emissions path (RCP2.6, SSP1-2.6), a historical run ( hist) for 1990– 2015 and a control run for a continuous 1995– 2014 climate ( ctrl_proj) under which the ice sheet is basically steady. The red and blue boxes to the right show the ways for RCP8.5/ SSP5-8.5 and RCP2.6/ SSP1-2.6, respectively; the hairs reveal the full ranges. Stage 1 is the initial ISMIP6 period up until 2100. Phases 2-4 are legitimate for RCP8.5/ SSP5-8.5 and show a sped up mass loss (stage 2), the primary instability of the West Antarctic ice sheet (stage 3) and a final stage 4 where the mass loss levels out. Map-view plots below are ice surface elevation differences relative to 2015 (in meters; blue means thickening, red/brown ways thinning) for the simulation required by MIROC-ESM-CHEM/RCP8.5. Credit: Christopher Chambers et al. Journal of Glaciology. December 22, 2021
Researchers anticipate that continued global warming under present patterns could lead to an elevation of the sea level by as much as five meters by the year 3000 CE.
One of the lots of impacts of international warming is sea-level increase due to the melting and retreat of the Earths ice sheets and glaciers along with other sources. As the sea level rises, large areas of largely populated coastal land might eventually become uninhabitable without comprehensive coastal modification. It is for that reason crucial to comprehend the effect of different paths of future environment change on modifications in sea level brought on by ice sheets and glaciers.
A team of researchers from Hokkaido University, The University of Tokyo and the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) checked out the long-term point of view for the Antarctic ice sheet beyond the 21st century under global-warming conditions, presuming late 21st-century weather conditions remain continuous. Their models and conclusions were released in the Journal of Glaciology.

The Ice Sheet Model Intercomparison Project for the Coupled Model Intercomparison Project Phase 6 (ISMIP6) was a major international effort that utilized the newest generation of models to approximate the effect of international warming on the ice sheets of Antarctica and Greenland. The goal was to provide input for the recently published Sixth Assessment Report (AR6) of the Intergovernmental Panel on Climate Change (IPCC). The contribution of the Antarctic ice sheet to sea-level rise by 2100 was assessed to be in the range between − 7.8 and 30.0 centimetres under unabated warming and in between 0 and 3 centimetres under minimized emissions of greenhouse gases.
The group used the ice-sheet design SICOPOLIS (SImulation COde for POLythermal Ice Sheets) to extend the entire ISMIP6 ensemble of fourteen experiments for the unabated warming pathway and 3 for the decreased emissions pathway. The team evaluated the outcomes of the simulations with regard to the total mass modification of the ice sheet, regional modifications in West Antarctica, East Antarctica and the Antarctic Peninsula, and also the various factors to mass modification.
The simulations of mass loss of the Antarctic ice sheet reveal that, by the year 3000, the unabated warming path produces a sea-level equivalent (SLE) of as much as 1.5 to 5.4 meters, while for the reduced emissions pathway the SLE would be just 0.13 to 0.32 meters. The primary reason for the decay under the unabated warming path is the collapse of the West Antarctic ice sheet, made possible by the fact that the West Antarctic ice sheet is grounded on a bed that is mostly well listed below water level.
” This research study demonstrates clearly that the effect of 21st-century environment change on the Antarctic ice sheet extends well beyond the 21st century itself, and the most severe effects– multi-meter contribution to sea-level rise– will likely only be seen later,” states Dr. Christopher Chambers of Hokkaido Universitys Institute of Low Temperature Science and lead author of the paper. “Future work will consist of basing simulations on more reasonable future environment situations, along with using other ice-sheet designs to design the outcomes.”
Referral: “Mass loss of the Antarctic ice sheet up until the year 3000 under a continual late-21st-century environment” by Christopher Chambers, Ralf Greve, Takashi Obase, Fuyuki Saito and Ayako Abe-Ouchi, 22 December 2021, Journal of Glaciology.DOI: 10.1017/ jog.2021.124.
This study was supported by Japan Society for the Promotion of Science (JSPS) KAKENHI (JP17H06323, JP17H06104) and Grant-in-Aid for Japan– France Integrated Action Program (SAKURA Program; JPJSBP120213203).

Simulated mass loss of the Antarctic ice sheet from 1990 until 3000 expressed as sea-level contribution: Fourteen experiments for the unabated warming path (RCP8.5, SSP5-8.5), three experiments for the reduced emissions pathway (RCP2.6, SSP1-2.6), a historical run ( hist) for 1990– 2015 and a control run for a continuous 1995– 2014 climate ( ctrl_proj) under which the ice sheet is essentially stable. Stages 2-4 are valid for RCP8.5/ SSP5-8.5 and reveal an accelerated mass loss (phase 2), the primary instability of the West Antarctic ice sheet (stage 3) and a last phase 4 where the mass loss levels out. Map-view plots listed below are ice surface area elevation differences relative to 2015 (in meters; blue means thickening, red/brown means thinning) for the simulation required by MIROC-ESM-CHEM/RCP8.5. The Ice Sheet Model Intercomparison Project for the Coupled Model Intercomparison Project Phase 6 (ISMIP6) was a major global effort that used the newest generation of designs to approximate the impact of international warming on the ice sheets of Antarctica and Greenland. The group evaluated the results of the simulations with regard to the overall mass modification of the ice sheet, local modifications in West Antarctica, East Antarctica and the Antarctic Peninsula, and likewise the various contributors to mass modification.