Earth's Oceans Rising, Ice Melting Faster than Ever, Study

Sea levels are rising faster than earlier estimates, claims a new study which revises existing numbers.

Researchers at University of Tasmania in Australia used tide gauges and satellite information to estimate sea level rise only to discover an overestimation of rise during 1993-99. The study attributes overestimation to land movement that disturbed tide gauges used during past measurements.

"Previously, it was clear that the rate of rise over the past 20 years was roughly double the rate determined over the past century - what was curious was that the rate appeared slower in the last decade relative to the one before," said lead author Dr. Christopher Watson.

Dr. Watson and his team realized that the rate of sea level rise in the last decade should be higher than previous decades as it is known that more water from Greenland and Western Antarctica entered Earth's oceans during this time.

Subsequently, the team found that the sea level rise over the last two decades was in fact 2.6 - 2.9 mm per year and not 3.2 mm per year as was earlier estimated. The decrease in the revised estimate is a result of overestimation during the first decade of 1993-2014. This indicates rate of sea level rise this year is higher than the previous years.

The research team also estimated that if greenhouse gas emissions are allowed to continue unabated, a sea level rise of 98 cm by 2100 is inevitable.

"Rising sea levels will place increasing stress on the coastal zone - inundation events will become more frequent and adaptation will need to occur. Agencies need to consider the impacts of accelerating sea levels and provide communities with advice and planning directions that are commensurate with the magnitude of the problem," Dr. Watson said.

The study has been published in the journal Nature Climate Change.