CLIMATE CHANGE CAUSES SEA LEVEL RISE TO ACCELERATE 50 PERCENT IN PAST 20 YEARS
A study published in the journal Nature Climate Change shows that global sea level rise increased by 50 percent between 1993 and 2014, the latest year for which data are available. In 2014, sea levels rose by 3.3 millimeters, more than an eighth of an inch, while in 1993 they rose 2.2 millimeters.
The paper reveals that the melting of the Greenland ice sheet was the major major contributor. In 1993, it accounted for only 5 percent of the increase, but in 2014 it was responsible for a quarter of the increase.
The document examines satellite measurements and tide gauges that measure sea level in the world.
Acceleration is particularly intense on the east coast of the United States, especially for Virginia and North Carolina. Some measures suggest that in these places, sea level is increasing three times faster than the global average.
There are several reasons for this, including a shipwreck of land, caused in part by the removal of groundwater.
Due to complex ocean currents, water levels are also higher in this region than elsewhere, and the addition of freshwater to the North Atlantic Ocean by the melting of Greenland is accelerating this trend, says Larry Atkinson, a professor of oceanography At the University of Virginia, T involved in the paper.
“This new evidence of accelerated rates concerns us as we try to advise local cities and regions on what it’s all about,” Atkinson said.
The most important factor in rising sea levels is thermal expansion. As the Earth warms, the ocean warms up, and warmer water takes up more space.
The fifth assessment report of the Intergovernmental Panel on Climate Change concluded that this phenomenon accounts for 30 to 55 percent of global sea level rise, while glacier melt represents 15 to 35 percent. The main sources of this water are the ice sheets that cover Greenland and Antarctica.
As for the loss of Greenland ice, “we do not know exactly why the rate increased because ice sheets are sufficiently dynamic and complex,” says co-author Xuebin Zhang, a scientist from the Australian Scientific Research And Commonwealth Industrial. The Sydney Morning Herald.
“Based on robust estimates of the Greenland ice sheet melting … maybe if the melting of the surface and also the ice discharge into the ocean progressively”
Bliss Zhang. “Both processes produce a shift of the mass of the ice sheet from Greenland to the ocean, as long as you have the mass movement of the land to the ocean, you will get this effect lifting the sea level.”