According to Xinhua News Agency, Beijing, September 10 – US scientists recently reported that they first observed using satellite data to “sea level fingerprint” that is melting ice caps lead to changes in the pattern of global sea level. This will help people to predict trends in sea levels in different regions and better respond to climate change.
The melting of the ice sheet will change the surface of the sea, resulting in varying degrees of sea level rise and fall, the formation of sea level fingerprints. The theoretical study of sea level fingerprints has been very thorough, but this is the first time scientists found direct evidence of sea level fingerprints.
The University of California, Irvine and the NASA Jet Propulsion Laboratory, used the latter two satellites from April 2002 to October 2014 to collect the gravity data to calculate the sea level fingerprints, And verified with submarine pressure observation data. Researchers report in a new issue of the journal Geophysics Newsletter that they calculated the freshwater quality from the land and the atmosphere to the ocean and plotted the distribution patterns of these freshwater in time and space. During this period, the global sea level increased by an average of 1.8 mm per year, in the low latitude sea area increased significantly, the polar part of the sea after a brief rise in the decline. Approximately 43% of the freshwater in the ocean comes from the Greenland ice sheet, 16% from the Antarctic and 30% from the mountains.
The ice sheet itself has great quality and will create pressure on the lower crust, and its gravitational force will bring the surrounding sea water to the ice sheet. After the ice sheet melts, both the pressure and the gravitational force disappears, causing the local gravity distribution to change and deflecting the Earth’s rotation axis. These factors together will make the sea surface terrain has changed greatly, the impact of different ice cover is also different.
Researchers say that according to the study, they can predict changes in the sea level at any point in the global ocean due to the melting of glaciers.