The Intergovernmental Panel on Climate Change, or IPCC, a branch of the United Nations that deals with assessing the effects of global warming on the globe, has estimated that sea levels worldwide will rise by about 30-35 centimeters in the next century, on account of the large quantities of carbon dioxide emitted into the atmosphere, and the melting of the ice sheets. Now, a new study shows that the increase could be by as much as three times higher, based on background studies the international team conducted over the past few years.

Researchers from England, Finland, and the Niels Bohr Institute at the University of Copenhagen, publishing in the prodigious journal Climate Dynamics, say that, by looking back in history and analyzing correlations between periods of warming and the level of the sea, they've found that water levels can vary very fast within the relatively-limited time frame of a century.

University of Copenhagen Niels Bohr Institute Center for Ice and Climate geophysicist Aslak Grinsted explains that “Instead of making calculations based on what one believes will happen with the melting of the ice sheets, we have made calculations based on what has actually happened in the past. We have looked at the direct relationship between the global temperature and the sea level 2000 years into the past.”

The team says that good examples to test its theories are illustrated by the 12th century, when a warm period prompted a 20cm increase in global water levels, and the “little ice age” of the 18th century, when levels dropped by as much as 25cm, compared to today's levels.

According to the IPCC model, ice sheet warm and break slower than the oceans do, which has been their main reason for giving out their rather “optimistic” forecast. However, data collected by Grinsted and colleagues proves that a three-degree-Celsius increase in temperature will undoubtedly force the ice to crack a lot faster, and a century is a very long time, considering that it is daily subjected to pressures from outside factors.