That's changing, Nerem said.
A study using satellite data found that not only are sea levels rising - but the rate is accelerating. The predicted sea level rise of 2 feet by century's end may not be catastrophic for wealthier countries, but it will be devastating for those without the money to deal with impacts of global warming.
However, the team suspected these estimates could double, saying: "The observed acceleration will more than double the amount of sea-level rise by 2100 compared with the current rate of sea-level rise continuing unchanged", the study read.
Leaders in coastal cities from NY to Shanghai are debating how to handle rising sea waters.
As the study notes, one of the main causes behind the accelerating sea level rise is the melting of ice sheets in Greenland and Antarctica - and this is one of the biggest variables that will impact how quickly the seas will continue to rise.
In the past 100 years, it has climbed about a foot or more in some US cities because of ocean currents and the natural settling of land - 11 inches in NY and Boston, 12 in Charleston, 16 in Atlantic City, 18 in Norfolk and 25 in Galveston, Texas, according to a USA TODAY analysis of tide gauge data collected by the National Oceanic and Atmospheric Administration.
25 years of satellite data shows global sea level surging at faster rate
"We have known from observations that the ice sheets and mountain glaciers have been losing mass at an accelerated rate over the past decade or so", Fernando Paolo, postdoctoral scholar at NASA's Jet Propulsion Laboratory, who was not involved with the study, told Newsweek. In addition, global sea level can fluctuate due to climate patterns such as El Ninos and La Ninos (the opposing phases of the El Nino-Southern Oscillation), which influence ocean temperature and global precipitation patterns. They say the accelerating sea level rise is due to ocean warming and melting ice sheets.
Other researchers reported that even a bit changes in levels of world's oceans may lead to erosion and flooding.
"Sixty-five centimeters is probably on the low end for 2100", Nerem said, "since it assumes the rate and acceleration we have seen over the last 25 years continues for the next 82 years".
The team also used tide gauge data to assess potential errors in the altimeter estimate. Scientists used 25 years of satellite data to evaluate the Earth's seas' levels.
Sea levels have been recorded by a series of four satellites, starting with the 1992 launch of the TOPEX/Poseidon satellite, in addition to long-term data captured by tidal gauges.
"This is the first satellite-based estimate of an acceleration number", Professor Nerem said. "They provide the only assessments of the satellite instruments from the ground".
Again, the melting of the Greenland ice sheet was put forward as the primary cause of this acceleration.
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Clearly, it is Manziel's goal to get back to the National Football League at some point, but that door is slammed shut right now. I know it's not the easiest way back for me. "The difference that I know this year is I started looking at my mental health".