Sea levels worldwide have risen an average of nearly 3 inches (8 centimeters) since 1992, the result of warming waters and melting ice, a panel of NASA scientists said Wednesday. In 2013, a United Nations panel predicted sea levels would rise from 1 to 3 feet (0.3 to 0.9 meters) by the end of the century.
The new research shows that the sea-level rise most likely will be at the high end of that range, said University of Colorado geophysicist Steve Nerem.
Sea levels are rising faster than they did 50 years ago and "it's very likely to get worse in the future," Nerem said.
The changes are not uniform. Some areas showed sea levels rising more than 9 inches (25 centimeters) and other regions, such as along the U.S. West Coast, actually falling, according to an analysis of 23 years of satellite data.
Scientists believe ocean currents and natural cycles are temporarily offsetting a sea-level rise in the Pacific, and the U.S. West Coast could see a significant hike in sea levels in the next 20 years.
Island nations
A rise in global sea levels of more than a meter is unavoidable, scientists say, but they are not sure exactly when, where or how much it will be.
The NASA experts, working with European scientists, say such major cities as Tokyo and Singapore, the U.S. state of Florida, and a number of island nations could disappear.
The scientists say current data suggest a rise in ocean levels of at least 1 meter is a certainty in the next 100 to 200 years. But they say it could be much more depending on rate of loss of the polar ice sheets around Greenland and Antarctica.
They are also unsure when and precisely where the Earth could expect to see such a catastrophic rise in sea levels, saying ocean currents and other natural cycles vary.
Melting ice sheets
According to Tom Wagner, the cryosphere program scientist at NASA, the paleoclimate record shows that sea levels can rise as much as 10 feet (3 meters) in a century or two, if the ice sheets fall apart rapidly.
"We're seeing evidence that the ice sheets are waking up, but we need to understand them better before we can say we're in a new era of rapid ice loss," he said.
Eric Rignot, glaciologist at the University of California-Irvine, said that as the planet warms, there is no reason to expect that ice sheets will melt at the same pace as they did in the past. According to the laws of physics, they will deteriorate faster. And they already are.
"We are not talking about futuristic scenarios," said Rignot.
"On a personal level, the data collected over the past few years make me more concerned about the decay of the ice sheets than I was in the past," he added. "As we go on, I think we are a bit more worried about what is happening."
Some information for this report came from AFP and Reuters.
[voanews.com]
26/8/15
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Related:
The new research shows that the sea-level rise most likely will be at the high end of that range, said University of Colorado geophysicist Steve Nerem.
Sea levels are rising faster than they did 50 years ago and "it's very likely to get worse in the future," Nerem said.
The changes are not uniform. Some areas showed sea levels rising more than 9 inches (25 centimeters) and other regions, such as along the U.S. West Coast, actually falling, according to an analysis of 23 years of satellite data.
Scientists believe ocean currents and natural cycles are temporarily offsetting a sea-level rise in the Pacific, and the U.S. West Coast could see a significant hike in sea levels in the next 20 years.
Island nations
A rise in global sea levels of more than a meter is unavoidable, scientists say, but they are not sure exactly when, where or how much it will be.
The NASA experts, working with European scientists, say such major cities as Tokyo and Singapore, the U.S. state of Florida, and a number of island nations could disappear.
The scientists say current data suggest a rise in ocean levels of at least 1 meter is a certainty in the next 100 to 200 years. But they say it could be much more depending on rate of loss of the polar ice sheets around Greenland and Antarctica.
They are also unsure when and precisely where the Earth could expect to see such a catastrophic rise in sea levels, saying ocean currents and other natural cycles vary.
Melting ice sheets
According to Tom Wagner, the cryosphere program scientist at NASA, the paleoclimate record shows that sea levels can rise as much as 10 feet (3 meters) in a century or two, if the ice sheets fall apart rapidly.
"We're seeing evidence that the ice sheets are waking up, but we need to understand them better before we can say we're in a new era of rapid ice loss," he said.
Eric Rignot, glaciologist at the University of California-Irvine, said that as the planet warms, there is no reason to expect that ice sheets will melt at the same pace as they did in the past. According to the laws of physics, they will deteriorate faster. And they already are.
"We are not talking about futuristic scenarios," said Rignot.
"On a personal level, the data collected over the past few years make me more concerned about the decay of the ice sheets than I was in the past," he added. "As we go on, I think we are a bit more worried about what is happening."
Some information for this report came from AFP and Reuters.
[voanews.com]
26/8/15
--
-
Related:
Scientists: Rising Sea Levels Threaten NASA Space Centers
Scientists Discover World’s Oceans Warming Faster Than Predicted
"Raise your voice, not the sea level," urges UN on World Environment Day
Ice Loss from Antarctic Glacier Unstoppable
Anstieg der Meeresspiegel ... Nasa schockt mit neuer Prognose...
ReplyDeleteFür die Nasa ist es eine unausweichliche Entwicklung. Die Meeresspiegel werden steigen - und zwar nicht nur um wenige Zentimeter. Eine neue Prognose kündigte das Ende ganzer Großstädte an.
Ein Anstieg der Meeresspiegel um mindestens einen Meter ist neuen Forschungsdaten zufolge in den kommenden 100 bis 200 Jahren unvermeidlich. Damit drohten niedrig gelegene Landstriche, darunter ganze Inselstaaten und Großstädte wie Tokio und Singapur, zu versinken, sagte der Leiter der Abteilung für Erderforschung der US-Weltraumbehörde Nasa, Michael Freilich, in Miami............http://www.n24.de/n24/Nachrichten/Wissenschaft/d/7203482/nasa-schockt-mit-neuer-prognose.html
27/8/15
NASA Predicts Three Feet of Sea Level Rise is Inevitable...
ReplyDeleteBased on decades of ocean monitoring and satellite data, disturbing reports were published by NASA on Wednesday. According to the findings, Earth may be destined for a 3-foot rise in global sea levels, no doubt posing untold consequences for mankind.
Since 1992, sea levels have risen, on average, by 3 inches a year. For some areas, that number increases to as many as 9 inches.
Making predictions on sea level rise is no easy task, and scientists rely on a number of techniques. In addition to spaceborne altimeters known as the Jason series, researchers also use floating ocean sensors like Argo, as well as a pair of gravity-measuring satellites called GRACE.
“To study sea level rise, the Jason series, GRACE, and Argo are the big three,” said oceanographer Josh Willis of NASA's Jet Propulsion Laboratory, the project scientist for the planned Jason-3 altimetry mission.
That altimetry data has demonstrated that around one-third of sea level rise is a result of the warming of current ocean water. That heat forces the water to expand.
The remaining two-thirds stems from melting land ice, especially in Greenland and West Antarctica, which has seen a significant increase in the last decade.............http://sptnkne.ws/DRU
28/8/15
The administrator of the U.S. National Aeronautics and Space Administration (NASA) says attention must be paid to new data forecasting an approximately one meter rise in sea levels by the turn of the century....
ReplyDelete“It sounds definitive and ominous because that’s the way nature works,” Charles Bolden Jr. told VOA Friday in Bangkok.
His comment came after a team of NASA scientists in the U.S. Wednesday briefed reporters on their research documenting an average nearly eight centimeter global sea level rise since 1992, the result of warming waters and melting ice...............http://www.voanews.com/content/nasa-chief-still-time-to-heed-ominous-sea-level-rise-data/2935921.html