Damage Cannot be Undone, Sea Levels To Rise

We have already set in motion the events that will lead to a sea-level rise of 1.1 metres by the year 3000. This conclusion was arrived at by the research model of sea level changes over millennial timescales, taking into consideration Earth's land ice and the warming of the oceans.

The changes are inevitable as the green house gases have triggered an irreversible warming of Earth. And, depending on the route we take to mitigate our emission levels, the damage could vary and also be worst.

The results of this study were published on Oct. 2 in IOP Publishing's journal Environmental Research Letters. It was conducted by researchers from Vrije Universiteit Brussel, Manchester Metropolitan University and the Universite catholique de Louvain. 

A 6.8 meters sea level rise could be expected in the next 1000 years if we opt for the high A2 emissions scenario adopted by the Intergovernmental Panel on Climate Change (IPCC). The researchers then analyzed the next IPCC scenarios namely the B1 and A1B that yielded a sea level rise of 2.1 and 4.1 meters respectively.

"Ice sheets are very slow components in the climate system; they respond on time scales of thousands of years," said co-author of the study Professor Philippe Huybrechts.

"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."

The Greenland ice sheet was responsible for more than half of the sea level rises; while the second highest contributor was the thermal expansion of the oceans.

This is indeed the first unique study made that took in consideration the glaciers, ice caps, the Greenland and Antarctic ice sheets and the thermal expansion of the oceans into a projection of sea-level rises. All of this was done with the aid of a climate modeling system called LOVECLIM.

"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. Mankind should limit the concentration of greenhouse gases at the lowest possible level as soon as possible. The only realistic option is a drastic reduction of the emissions. The lower the ultimate warming will be, the less severe the ultimate consequences will be," said Huybrechts.