The world might be in for a rise in sea levels to at least six meters (20 feet) over the next couple of hundred years at the earliest as a result of global warming, scientists warn.
The warning was triggered by a new study published this week in the journal Science that shows an eerie similarity to today's ocean temperatures with temperatures from 125,000 years ago, a time that saw the Earth's last "warm period" during the Last Interglacial Period.
What has scientists troubled is the knowledge sea level rise 125,000 years ago was about 20 feet to 30 feet higher compared to the present. This indicates sea level rise may will continue in the years to come -- and will get worse.
The study shows that while temperatures from the Last Interglacial Period were similar to those in pre-industrial times, they increased by 0.5 degrees Celsius about 4,000 years into the epoch. That led to global temperatures more similar to the 1995-2014 average.
"The trend is worrisome as sea levels during the last interglacial period were between six and nine meters (20-30 ft) above their present height," noted Science about the study led by Jeremy Hoffman at Oregon State University.
Scientists, however, aren't able to predict how long a sea level rise of 20 meters might take. Some scientists say it could occur in about 200 years from now with others saying this phenomenon will take thousands of years to produce.
The new study, however, is another reason to be worried about how climate change is causing relentless sea level rise.
"The study suggests that, in the long term, sea levels will rise six meters at least in response to the warming we are causing," said Andrew Watson, a climate scientist from the University of Exeter, who did not take part in the study.
Another scientist said sea level rise is inevitable but an increase in oceans heights to six meters won't take place any time soon.
"The result that present global sea surface temperatures are indistinguishable from those at the last interglacial 125,000 years ago is extremely worrying since sea levels were six to nine meters higher then compared to present," said Richard Allen, a University of Reading professor of climate science not involved in the study.
"Due to the length of time it takes to heat up the depths of our vast oceans and to melt giant ice sheets it would take thousands of years before sea level could potentially rise to such levels, so sustained and substantive cuts in greenhouse gas emissions from energy-intensive activities remain vital and beneficial to societies."