Antarctica Ice Shelf Cracks-Warning For The Global Sea-Level Rise?
3 min read
By: Prof. Jaswant Singh, Member-Indian Scientific Expedition to Antarctica & Arctic, Director-Institute of Earth Sciences & Editor-ICN Group
Scientists believe that the entire West Antarctica Ice Sheet is likely to collapse within the next 100 years, sending a massive volume of water into the sea.
The data collected by the researchers on Climate change and their forecasts based on General circulation model (GCM), Earth’s and ocean water temperature is increasing. This is not only affecting the terrestrial and aquatic ecosystem but human life also. Climate change is the challenge of our generation.
The planet’s average surface temperature has risen about 1.8 degrees Fahrenheit (1.0 degree Celsius) since the late-19th century, a change largely driven by increased carbon dioxide and other human-made emissions into the atmosphere. Earth’s 2015 surface temperatures were the warmest since modern record keeping began in 1880, according to independent analyses by NASA and the National Oceanic and Atmospheric Administration (NOAA).
Recently in the year 2015 when a giant (225 square mile) slice of Antarctica’s Pine Island Glacier broke off, scientists were searching the exact cause of this crack. According to scientists, warming oceans water intruded the sheet at the bedrock well below sea level, triggering cracks that gradually made their way upward. In other words, Antarctic ice could be much more susceptible to breaking up than it seems on the surface, and that separation may be happening faster.
According to study published in Geophysical Research Letters by Ian Howat of Ohio State University, noting that iceberg break-offs of this size happen about every 5 to 6 years at Pine Island. But very important question is how it got started? Analyzing several years of images taken by the Sentinel-1A satellite, Howat and his colleagues traced the break-off to a rift that formed at the base of the ice shelf nearly 20 miles inland, in 2013. Over the course of two years, the rift propagated all the way from bottom to top, until finally, it spat out a huge iceberg.
The currents off Antarctica are warmer and carry saltier water that encourages melting. The sea temperature is about 5 degrees Celsius, which is far warmer than the average surface temperature of minus 20 C. That causes a twofold vulnerability for the ice, because some of it is located underwater and because it is exposed to the warm sea around it.
Ice loss from West Antarctica is already making a very significant contribution to global sea-level rise, and is actually one of the largest uncertainties in global sea-level predictions. The melting in Antarctica has a direct result of coastal cities across the globe. If the Ice shelf break is an early warning, it reinforces predictions that humanity is going to face severe consequences of climate change.
Scientists believe that the entire West Antarctica Ice Sheet is likely to collapse within the next 100 years, sending a massive volume of water into the sea. That would be enough to raise the global sea level by almost 10 feet, flood coastal cities, damage the property and human life across the globe.
About Author
