Seas are rising way faster than any time in past 2,800 years
Seas are rising way faster than any time in past 2,800 years A view from the air shows the destroyed homes left in the wake of Superstorm Sandy in Ortley Beach, N.J. (AP Photo/Mike Groll, File/Thinkstock)
Seas are rising way faster than any time in past 2,800 years
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Sea levels on Earth are rising several times faster than they have in the past 2,800 years and are accelerating because of man-made global warming. This is according to new studies.
An international team of scientists dug into two dozen locations across the globe to chart gently rising and falling seas over centuries. Until the 1880s and the world's industrialization, the fastest seas rose was about 1 to 1.5 inches a century, plus or minus a bit. During that time, global sea level really didn't get much higher or lower than 3 inches above or below the 2,000-year average.
But in the 20th century, the world's seas rose 5.5 inches. Since 1993, the rate has soared to a foot per century. And two different studies, published in February in the journal Proceedings of the National Academy of Sciences, said that by 2100 that the world's oceans will rise between 11 to 52 inches. The actual level will depend on how much heat-trapping gas Earth's industries and vehicles expel.
"There's no question that the 20th century is the fastest," said Rutgers University's Bob Kopp.  He is an earth and planetary sciences professor. He is lead author of the study that looked back at sea levels over the past three thousand years. "It's because of the temperature increase in the 20th century, which has been driven by fossil fuel use."
To figure out past sea levels and rates of rise and fall, scientists engaged in a "geological detective story." That is how study co-author Ben Horton described it. He is a Rutgers marine scientist. The scientists went around the world looking at salt marshes and other coastal locations. They used different clues to figure out what the sea level was at different times. They studied single cell organisms that are sensitive to salinity, mangroves, coral, sediments and other clues in cores, Horton said. On top of that, they checked their figures by easy markers. Those included the rise of lead with the start of the industrial age and isotopes only seen in the atomic age.
Kopp and colleagues charted the sea level rise over the centuries. They saw Earth's sea level was on a downward trend until the industrial age.
Sea level rise in the 20th century is mostly man-made, the study authors said. A separate, not-yet-published study by Kopp and others found since 1950, about two-thirds of the U.S. nuisance coastal floods in 27 locales have the fingerprints of man-made warming.
And if seas continue to rise, as projected, another 18 inches of sea level rise is going to cause lots of problems and expense. That will be especially true with surge during storms, said study co-author Stefan Rahmstorf. He works at the Potsdam Institute for Climate Impact Research in Germany.
"There is such a tight relationship between sea level and temperature," Horton said. "I wish there wasn't. Then we wouldn't be as worried."
The link to temperature is basic science, the study's authors said. Warm water expands. Cold water contracts. The scientists pointed to specific past eras when temperatures and sea rose and fell together.
The Kopp study and a separate one published by another team projected future sea level rise based on various techniques. They came to the same general estimates. This was despite using different methods, said Anders Levermann, a co-author of the second paper and a researcher at the Potsdam Institute.
If greenhouse gas pollution continues at the current pace, both studies project increases of about 22 to 52 inches. If countries fulfill the treaty agreed upon last year in Paris and limit further warming to another 2 degrees Fahrenheit, sea level rise would be in the 11- to 22-inch range.

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How do rising seas affect us on land?
Write your answers in the comments section below

  • Eric0221-YYCA
    3/09/2016 - 11:20 p.m.

    The temperature might have been the same as the sea level because the hotter the temperature is, the more the sea level would rise from the ocean and risk people's lives that live in coastal cities. The sea level rising had been risking lives to be in danger that are living in coastal cities which would risk the lives of people that are living in coastal cities near the ocean. The sea level rising would mean that people would be risking their lives when coastal cities had flooded the coastal cities due to man-made things that had threatened people lives at risk for floods. Scientists might have been studying the danger of sea level rising which will be taking down the lives of people that live in coastal cities that are risking with floods.
    Critical Thinking Question: How do rising seas affect us on land?
    Answer: Rising seas would be affecting us on land being when the water from the ocean rises up to the streets, we wouldn't be able to step a foot on the flooded streets.

  • noahi-fel
    3/22/2016 - 02:27 p.m.

    It could shrink our land mass

  • travond-fel
    3/23/2016 - 02:15 p.m.

    its caused by man made global warming

  • mattv-fel
    3/23/2016 - 02:16 p.m.

    Rising Seas could make it so that cities have to begin building somewhere high up, as the water could flood areas where water is present.

  • coled-fel
    3/23/2016 - 02:16 p.m.

    CTQ: Rising seas affect us on land because that means less land for hoomanz.

  • lucasp-fel
    3/23/2016 - 02:17 p.m.

    the seas are effecting us by washing away houses and flooding around the shores

  • victoriae-fel
    3/23/2016 - 02:17 p.m.

    Rising seas effect us on land because it means that there isn't as much land.

  • johnj-fel
    3/23/2016 - 02:18 p.m.

    Rising seas affects us on land because it can shrink our land mass because more and more water will be pushing closer to shores and more inland.

  • haleyd1-fel
    3/23/2016 - 02:19 p.m.

    The rising seas affect us on land because it shrinks our land mass.

  • elizabetht-fel
    3/23/2016 - 02:20 p.m.

    Rising seas affect land mass by either making our land mass smaller by erosion, a shift in weather pattern; causing either flood or drought, and the flora and fauna may be adversely affected.

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