Sea waters are rising alarmingly and in the last 30 years, sea rose by 9.1 centimetres, according to the assessment by NASA.
In the assessment, NASAalso said that the projected rate of sea level rise will hit 0.66 centimeters per year by 2050 based on continued long-term satellite measurements,
CULPRITS OF SEA RISE
Humans are the main culprits in sea level rising. Excess amounts of greenhouse gases like carbon dioxide that humans pump into the atmosphere. Climate change has a number of effects across the globe, but it’s particularly obvious in Earth’s ice sheets and glaciers. NASA pointed out that Antarctic ice sheet experienced above-average melting, even accounting for summer temperatures, just this past year alone.
Noting that the stability of Greenland’s ice pack has changed a great deal, the analysis said that Greenland Ice Sheet is a major contributor to sea level rise. That’s because its runoff and water from the Antarctic ice add more fresh water to the ocean while warming causes the expansion of seawater. The result is rising seas which override other natural effects on sea surface height.
TRACKING SEA HEIGHT FROM SPACE
One of the best and most accurate way to track ocean height rise is with space-borne instruments on satellites.The US-French TOPEX/Poseidon mission began measuring sea surface height in 1993. Since then, sea-level observations continued through missions led by NASA, ESA, and the US National Oceanic and Atmospheric Administration (NOAA).
“We have this clear view of recent sea level rise – and can better project how much and how quickly the oceans will continue to rise – because NASA and Centre National d’ÉtudesSpatiales (CNES) have gathered decades of ocean observations.
“By combining that data with measurements from the rest of the NASA fleet, we can also understand why the ocean is rising,” said Karen St. Germain, director of NASA’s Earth Science Division in Washington.
The 30-year satellite record not only shows long-term trends but allows scientists to see through naturally occurring shorter-term shifts.
“That helps us identify the trends that tell us where sea level is headed,” said JPL’s Ben Hamlington, a researcher who leads NASA’s Sea Level Change science team.
EFFECTS OF SEA-LEVEL RISE
The observations help shape the types of services that the governments offer to coastal communities. As this rise continues, at least 800 million people will be facing at least a half-meter rise in water levels. In practical terms, that places such as Miami, New York, Bangkok, Shanghai, Lima (Peru), Cape Town, and many others, will suffer continual seawater incursions.
Coastal regions in the US alone are home to more than half the country’s population. They contain major shipping ports, as well as recreational areas, and other facilities. The major physical impacts of sea level rise also threaten wildlife populations, delta regions, marshes and wetlands.
“Tracking the greenhouse gases that we add to the atmosphere tells us how hard we’re pushing the climate, but sea levels show us how much it’s responding,” said Josh Willis, an oceanographer at NASA’s Jet Propulsion Laboratory in Southern California.
