Question+3

Through the evidence of a graph made from 3-year averages of sea levels from 1880 and Satellite altimetry in recent years, it is possible to note that sea levels have risen a full 20 centimeters between 1880 and 2000. Here is a link to the website:

On the NASA Earth Observatory website, there is a chart of rising sea levels charted by three satellites, (TOPEX, Poseidon, Jason) and Argo, a global array of 3,000 free-drifting profiling floats that measures the temperature and salinity of the upper 2000 meters of the ocean. This chart shows the level measurements taken at different times, a 60-day average of these measurements, and a line showing the trend that goes steadily upward through the graph.

[] These graphs show that the general opinion is that sea levels have risen considerably over the past few centuries.

More evidence of rising sea levels include the east coastal U.S. Cities. One example of this is Louisiana, which is effected by rising sea levels because they are low lying. A prediction was made that over the next century Louisiana will lose 9,546 square mile of coastal low land. The reason this is happening is the quickly melting Greenland ice sheet is adding to the sea level around the coastal areas of the U.S. Louisiana and other coastal states have lost much land.

One possibility of lessening sea level rise is to place large tarpaulins over large areas of glacial land. Due to coal smoke output from large cities, there are issues with coal dust covering areas of ice and causing them to attract heat. Thus, in this case, comes to mind the universal “lessen pollution”. Another adaptation for rising sea levels is “lily pad cities”, large, self-sustaining ships with all the outfittings of a city, which offer a long-term solution to the issue of where people will live and how they will find sufficient provender to meet their needs in an era of risen and rising sea levels.

Within the scientific community there is growing consensus that the overall worldwide rate of sea level rise during the 20th century has been nearly 2 mm per year, sharply higher than the average of the past several millennia. There is also consensus amongst this same community that global sea level does experience a natural temporal variability from minute-to-minute, century-to-century, and millennium-to-millennium that is completely unrelated to any human activities and, that this component of global sea level rise is difficult to measure or predict. Additionally, the majority of the scientific community is in agreement that human activity, not nature, has been the main cause of the Earth’s changing climate over the past century, and that the increase in global temperature has resulted in an increase in the rate of sea level rise, largely due to thermal expansion and glacial melting. This being said, however, there are global-warming skeptics, who believe that the projected increase in the rate of sea level rise attributable to human activity is overstated. They argue that the actual climate is still far more complicated than any existing computer model can accurately reflect, making predictions “iffy” at best. (Lemonick, M.D.) They suggest that some yet unrevealed natural processes could end up blunting even the most severe impacts of global warming. Michael Opennheimer, a professor of geosciences and international affairs at Princeton University, responds to the global warming skeptics by saying,”I worry every day about other surprises. It would be the height of arrogance to assume that there won’t be [surprises]. Some of the surprises may cut in our favor, but I’d hate to count on that. We have only one world to play with.” (Lemonick, M.D.) Regardless of whether the rate of sea level rise remains at the current 2 mm per year level, which appears by all evidence to be unlikely, or increases to anywhere between 3.5 mm and 8 mm per year, as suggested by various widely accepted scientific models, the social and economic issues that must be dealt with remain. Planning for sea level rise is necessary, not just to save economic resources but human lives as well.
 * By Nicole Phelan - ACS Cobham**

