New research has bring out a “ worrying ” way that large ice rink sheets can melt through warm seawater imbrication against the bottom of flat coat - based chalk . The researcher consider the discovery might even be a new " clime tipping point " – a critical threshold that , when crossed , pass to runaway change and totally upends an constituent in Earth ’s system .
The burden was recently name by scientists at the British Antarctic Survey ( BAS ) , establish on old inquiry that has indicate fond ocean water cansneak large distancesbeneath crank sheets .
The new study examine how brine can infiltrate the space between the land and the overlying ice flat solid that rests on it , do localized sparkler melting . This process lubricates the ice bed and influences the rate at which the ice could slide toward the ocean , leading to further fuss .
“ Ice sheets are very sensitive to melting in their foundation zone . We find that grounding zona melting display a ‘ tipping breaker point - like ’ behaviour , where a very small change in ocean temperature can make a very big increase in ground zone melting , which would lead to a very big change in flow of the ice above it , ” Alex Bradley , lede study author and methamphetamine hydrochloride dynamics research worker at BAS , said in astatement .
Antarctica ’s ice was once thought to be relatively static , at least compared to its polar counterpart in the Northern Hemisphere , the Arctic . Between 1978 and 2015 , while Arctic ice was evaporate away , the extent of Antarctic sea crank increased slowly and steadily .
However , Antarctica ’s ice extent has suffered a notable decline in recent years . In 2017 , Antarctic sea ice crashed to a record low gear , followed byseveral years of comparatively depressed sea ice extent . More bad tidings came in 2022 and – most significantly – in 2023 when it reach anew book low .
The researcher of this in style subject field say that this fresh appreciated way of melting could offer a more accurate ( and perhaps more damning ) picture of howAntarcticaand Greenland will change in the face of climate variety .
“ We have identify the possibility of a newtipping pointin Antarctic ice rag melting . This means our projections of ocean degree ascending might be important underrating , ” excuse Bradley .
“ This is missing physics , which is n’t in our methamphetamine bed sheet models . They do n’t have the power to simulate melting beneath grounded ice , which we think is happening . We ’re turn on set that into our models now , ” he added .
The raw study is print in the journalNature Geoscience .
