Brussel: Greenhouse gas emissions, relentlessly driving global climate change, will continue to push up sea levels for thousands of years, says a study.
The study sought to model sea-level changes over millennial timescales, factoring in earth’s land ice and the warming of the oceans — something which has not been done before.
The research showed that we have already committed ourselves to a sea-level rise of 1.1 metres by the year 3000 as a result of our emissions up to now, the journal Environmental Research Letters reports.
This irreversible damage could be worse, depending on the route we take to mitigating our emissions.
“Ice sheets are very slow components in the climate system; they respond on time scales of thousands of years,” said study co-author Philippe Huybrechts professor of geography, Vrije Universiteit Brussel, Belgium.
“Together with the long life-time of greenhouse gases in the atmosphere, this inertia is the real poison on the climate system: anything we do now that changes the forcing in the climate system will necessarily have long consequences for the ice sheets and sea level,” added Huybrechts.
In all of the analysed scenarios, the Greenland ice sheet was responsible for more than half of the sea level rises; thermal expansion of the oceans was the second highest contributor; and the contribution of glaciers and ice was only small, according to a Vrije statement.
The researchers believe this is the first study to include glaciers, ice caps, the Greenland and Antarctic ice sheets and the thermal expansion of the oceans into a projection of sea-level rises.
They did so by using a climate modelling system called LOVECLIM, which includes components from a number of different subsystems.
“Ultimately the current polar ice sheets store about 65 metres of equivalent sea level and if climatic warming will be severe and long-lasting all ice will eventually melt,” Huybrechts said.