Monitoring Desk
ISLAMABAD: Substantial El Nino events caused by world heating may accelerate the irreversible melting of the Antarctic ice sheet and ice shelves, leading to rising sea levels, according to research from Australia’s premier government science agency.
The latest study has found that increasing atmospheric greenhouse gas concentrations were expected to increase the magnitude of the El Niño Southern Oscillation (Enso) — the planet’s most significant year-to-year climate fluctuation and a primary driver of extreme droughts and floods.
The study said that extreme warm El Niño events and extraordinary La Nina events were expected to become frequent as the planet heats up.
“Relatively little is known about the impact of Enso changes in Antarctica,” the new study published in the journal Nature Climate Change led by CSIRO researchers said. The study found that more vital El Niño events were likely to have divergent impact in the ocean surrounding the southern continent.
“The examination of 31 climate model found that stronger El Niños may accelerate the heating of deeper ocean water while slowing the pace of warming on the surface as westerly wind along the continental shelf become less intense,” it said.
Ice shelves and ice shelves melting
Dr Wenju Cai, a chief research scientist at CSIRO and the study’s lead author, said the events would lead to the ice shelves and ice sheet melting faster. The study didn’t say how much more rapidly melting may occur.
The Antarctic ice sheet is estimated to contain about 30 m cubic kilometers of ice, enough to increase the global sea level by 70m over centuries if completely melted.
A separate recent study estimated that world temperatures of 1C above pre-industrial levels, a point already passed, would be enough to gradually collapse the West Antarctic ice sheet, leading to four meters of sea level rise.
