Uncontrolled greenhouse gas emissions could lead to more than a 15-inch rise in sea levels, scientists have concluded that they use NASA data to issue a strong warning about melting ice. The huge increase would lead to dramatic floods in coastal regions around the world and create a potentially apocalyptic chain reaction with consequences.
Global warming conditions have already been signaled for existing ice melting and rising sea levels. According to the Ice Sheet Model Intercomparison Project (ISMIP6), led by NASA’s Goddard Space Flight Center in Greenbelt, Maryland, there is further melting to consider.
It saw more than 60 specialists in ice, sea and atmospheric research ̵
In 2100, they concluded, and if greenhouse gas emissions are reduced from their current levels, the combined ice bed melt could lead to more than 15 inches of global sea level rise. Melting water from these ice sheets is assumed to account for about one third of the total global sea level rise. Previous studies have suggested that, even if we make changes now, sea levels will increase by about a quarter of an inch by 2100.
“One of the biggest uncertainties about how much sea levels will rise in the future is how much the ice sheet will contribute,” Sophie Nowicki, now at the University of Buffalo, and formerly at NASA Goddard, and project manager for the study, said today. “And how much the ice sheet contributes really depends on what the climate will do.”
The challenge is that there is a double impact that causes the ice sheets at the North and South Poles to shrink and in the process release large amounts of water. On the one hand, the air temperature increases, which melts the ice level on the surface. At the same time, sea temperatures are rising, causing glaciers to shrink and retreat. A study in August predicted that unexpectedly unsafe ice shelves in Antarctica may be prone to cutting away, in the process dramatically increasing the rate at which ice melts.
The latest study examined two possibilities. On the positive side, the team modeled a scenario with lower emissions, where carbon dioxide emissions were dramatically reduced. It still saw global sea levels rise by about 1.3 inches.
The second model took a more pessimistic view, where emissions increased slightly in the way of attempts to control their production. There, they concluded that melting ice sheets could add about 3.5 inches to the already rising oceans.
Lending additional complexity is the fact that the changes and melting rates are not consistent in all areas. Some regions are more sensitive to warmer seas and differences in currents: Amundsen’s sea sector in western Antarctica and Wilkes Land in eastern Antarctica, for example, are mentioned as the most exposed to changes in the simulations.
“With these new results, we can focus our efforts in the right direction and know what needs to be worked on to continue to improve projections,” said Hélène Seroussi, an ice scientist at NASA’s Jet Propulsion Laboratory in Southern California, leading to Antarctica. modeling of ice sheets, explains.