As per NASA, the projections made by the Intergovernmental Panel on Climate Change on a rise in global sea levels of 1 to 3 feet have already become a thing of past. Experts said that humans are locked into at least 3 feet of sea level rise and even more is also possible.

Steven Nerem of the University of Colorado said that most of the experts have been think that the sea level rise would be towards the higher end of that range. The news is especially a matter of concern for people who live near to the ocean.

As per experts, there are three main reasons behind sea level rise and those are expansion of warmer ocean water, melting mountain glaciers and ice loss from the massive Greenland and Antarctica ice sheets.

NASA has raised concerns about the last cause. The agency has announced that it will be focusing on the last reason as a part of intensive research effort. One of the research projects is Oceans Melting Greenland.

Under this project, experts will try to know how the Greenland Ice Sheet is adding to sea level rise. The study is expected to continue for six years. Experts have said that glacier drains contribute more to sea level rise in comparison to other features in the Northern Hemisphere.

NASA scientist and ice expert Tom Wagner said that if complete ice sheet in Greenland melts then global sea levels rise would be of around 20 feet, but this loss is not going to happen anytime soon.