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Update Date: 2009/02/11 18:13
If experts' predictions are accurate, the melting or collapse of the West Antarctic ice sheet due to global warming, as indicated by recent research, will have a "significantly greater" impact on sea level rise in many parts of the United States than currently simulated.
Scientists suggest that the global sea level rise might be more severe than expected. For instance, while the current predicted average global rise is 16 to 17 feet, in the Washington D.C. area, it could increase to 21 feet, submerging much of the capital. The southeastern coast and southern Florida could disappear under the waves.
This research, a collaboration between Oregon State University and the University of Toronto, was published in the February 6 issue of the journal Science, titled "The Sea Level Fingerprint of West Antarctic Ice Sheet Collapse."
Peter Clark, a professor of geosciences at Oregon State University, stated, "This report does not announce the imminent collapse of the Antarctic ice sheet, but much of the ice edge has already melted into floating ice shelves, including the largest Ross Ice Shelf and Ronne Ice Shelf, indicating potential instability."
This concern echoes recent research by University of Washington professor Eric Steig, who pointed out that the West Antarctic ice sheet is indeed warming.
As early as 2005, a team from NASA and universities found clear evidence that a large area of snow in West Antarctica was melting, the most significant melt observed by satellites in the past 30 years.
Clark explained, "It is still unclear whether the West Antarctic ice sheet will indeed collapse, or when it might happen; it may not occur for the next few hundred years, or it may not completely collapse. Related research should continue to track the state of the ice sheet."
The United Nations Intergovernmental Panel on Climate Change (IPCC) predicts that the collapse of the West Antarctic ice sheet would cause an average sea level rise of 16.5 feet, a figure still widely cited. However, Clark and his team believe this prediction is too theoretical and does not consider several key factors in the actual situation, such as gravity, differences in Earth's rotation, and the reactive force caused by the pressure of ice-covered land.
Currently, the West Antarctic ice sheet still has massive ice blocks over 6000 feet high on the vast Antarctic continent, creating a gravitational pull on seawater. Researchers explain that just as the sun and moon create gravity on Earth, influencing tides, the ice sheet also exerts a pulling force.
This study adds other factors to the calculation of sea level rise, including the reactive force caused by the pressure of the ice sheet on the land and its impact on Earth's rotational axis. As the ice sheet gradually melts, the land itself will rise due to reactive force; Earth's rotational axis will shift by 1/3 mile, affecting the extent of sea level rise in different regions.
Considering these variables, the report concludes that sea levels near Antarctica will drop, while sea levels in the Northern Hemisphere will rise.
If the West Antarctic ice sheet completely melts, the sea level on the east coast of North America will rise by 21 feet—4 feet higher than previously estimated. The west coast and Miami will face a sea level rise of 22 feet.
Most of Europe will see a sea level rise of about 18 feet, and countries south of the Indian Ocean will also face the risk of coastal flooding.
Source: http:/ / tw. news. yahoo. com/ art……rl/ d/ a/ 090211/ 109/ 1eavm. html
US Study: Antarctic Ice Melt to Further Raise North American Sea Levels
If experts' predictions are accurate, the melting or collapse of the West Antarctic ice sheet due to global warming, as indicated by recent research, will have a "significantly greater" impact on sea level rise in many parts of the United States than currently simulated.
Scientists suggest that the global sea level rise might be more severe than expected. For instance, while the current predicted average global rise is 16 to 17 feet, in the Washington D.C. area, it could increase to 21 feet, submerging much of the capital. The southeastern coast and southern Florida could disappear under the waves.
This research, a collaboration between Oregon State University and the University of Toronto, was published in the February 6 issue of the journal Science, titled "The Sea Level Fingerprint of West Antarctic Ice Sheet Collapse."
Peter Clark, a professor of geosciences at Oregon State University, stated, "This report does not announce the imminent collapse of the Antarctic ice sheet, but much of the ice edge has already melted into floating ice shelves, including the largest Ross Ice Shelf and Ronne Ice Shelf, indicating potential instability."
This concern echoes recent research by University of Washington professor Eric Steig, who pointed out that the West Antarctic ice sheet is indeed warming.
As early as 2005, a team from NASA and universities found clear evidence that a large area of snow in West Antarctica was melting, the most significant melt observed by satellites in the past 30 years.
Clark explained, "It is still unclear whether the West Antarctic ice sheet will indeed collapse, or when it might happen; it may not occur for the next few hundred years, or it may not completely collapse. Related research should continue to track the state of the ice sheet."
The United Nations Intergovernmental Panel on Climate Change (IPCC) predicts that the collapse of the West Antarctic ice sheet would cause an average sea level rise of 16.5 feet, a figure still widely cited. However, Clark and his team believe this prediction is too theoretical and does not consider several key factors in the actual situation, such as gravity, differences in Earth's rotation, and the reactive force caused by the pressure of ice-covered land.
Currently, the West Antarctic ice sheet still has massive ice blocks over 6000 feet high on the vast Antarctic continent, creating a gravitational pull on seawater. Researchers explain that just as the sun and moon create gravity on Earth, influencing tides, the ice sheet also exerts a pulling force.
This study adds other factors to the calculation of sea level rise, including the reactive force caused by the pressure of the ice sheet on the land and its impact on Earth's rotational axis. As the ice sheet gradually melts, the land itself will rise due to reactive force; Earth's rotational axis will shift by 1/3 mile, affecting the extent of sea level rise in different regions.
Considering these variables, the report concludes that sea levels near Antarctica will drop, while sea levels in the Northern Hemisphere will rise.
If the West Antarctic ice sheet completely melts, the sea level on the east coast of North America will rise by 21 feet—4 feet higher than previously estimated. The west coast and Miami will face a sea level rise of 22 feet.
Most of Europe will see a sea level rise of about 18 feet, and countries south of the Indian Ocean will also face the risk of coastal flooding.
Source: http:/ / tw. news. yahoo. com/ art……rl/ d/ a/ 090211/ 109/ 1eavm. html