Sea level will rise by at least one meter in the next 130 years

Continued and prolonged sea level rise is a real threat, say UN scientists

The fusion model simulations of ice caps they have been widely used to assess how much their melting ice might contribute to future global sea level rise. In general, these projections do not take into account the two-way interactions between ice caps and climate.

To quantify the impact of feedback ice-ocean-atmospherea group of researchers from the universities of Korea and Hawaii carried out greenhouse warming simulations with a coupled global climate-ice sheet model of intermediate complexity.

The study just published in Nature Communications shows that an irreversible loss of the ice caps of Greenland and the West Antarcticaand the corresponding rapid acceleration in sea level rise, may be imminent if global temperature change cannot stabilize below 1.8°C above pre-industrial levels.

The temperature continues to rise each year and the Earth warms, resulting in the constant loss of ice mass in glaciers.

The vast majority of coastal populations around the world are already preparing for the increase in sea ​​level. However, planning countermeasures to prevent flooding and other damage has been extremely difficult because the latest climate model projections presented in the Sixth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) are not disagree on how quickly major ice caps will be removed.

He merger ice sheets is potentially the largest contributor to sea level change, and historically the most difficult to predict because the physics governing its behavior is notoriously complex.

“Furthermore, computer models simulating the dynamics of the Greenland and Antarctic ice sheets often fail to account for the fact that melting will affect ocean processes which, in turn, can affect the ice sheet and the atmosphere,” explained Jun Young Park, PhD specialist at the IBS Center for Climate Physics and Pusan ​​National University, Busan in South Korea and first author of the paper.

Using a new technological model that captures for the first time the coupling between ice caps, icebergs, the ocean and the atmosphere the team of climatologists discovered that a vanishing effect Growth in ice cover and sea level can only be prevented if the world reaches baseline temperature and zero carbon emissions by 2060.

“If we don’t meet this emissions target, the ice caps will disintegrate and they will melt at an accelerated rate, according to our calculations. Unless we act, melting ice caps will continue to raise sea levels by at least 100 centimeters in the next 130 years. This would be in addition to other contributions, such as the thermal expansion of ocean water,” said study co-author Axel Timmermann, director of the IBS Center for Climate Physics.

Ice sheets respond to atmospheric and oceanic warming in late and often unpredictable ways. Previously, scientists have highlighted the importance of subsurface ocean melting as a key process, which can trigger runaway effects on major Antarctic ice sheets.

When sea levels rise rapidly, as they have in recent times, even a small rise can have devastating consequences for coastal habitats.

“However, according to our simulations, the effectiveness of these processes may have been overestimated in recent studies. We find that sea ice and changes in atmospheric circulation around Antarctica also play a crucial role in controlling the amount of ice sheet melt, with implications for sea-level projections at sea level. ‘global scale,’ said Professor June. Yi Lee of the IBS Center for Climate Physics and Pusan ​​National University and co-author of the study.

The study highlighted the need to develop more complex Earth system models that capture the different components of climate, as well as their interactions. In addition, new observing programs are needed to constrain the representation of physical processes in Earth system models, especially of highly active regions such as the Pine Island Glacier in Antarctica.

“One of the main challenges of ice sheet simulation is that even modest processes can play a crucial role in the large-scale response of an ice sheet and the corresponding sea level projections. We must not only include the coupling of all the components, as we did in our current study, but we also need to simulate the dynamics with the highest possible spatial resolution using some of the fastest supercomputers,” concluded Axel Timmermann.