Ice Melt in Greenland and Antarctica is on A Higher Level

Ice melt in Greenland and Antarctica, Earth's great ice sheets are now widespread, and they are losing at such a high speed. The rate of melting is six times higher in comparison to their condition in the 1990s. It is the ultimate result of global warming. 

Scientists have got satellite reviews that are comprehensive as the technology are very close to both of the poles.

In the time from 1992 to 2017, Greenland and Antarctica lost nearly 6.4 trillions of ice. As a consequence, the world will face a 17.8mm rise of water in the sea-levels.

Andrew Shepherd, a professor from the University of Leeds, UK, says it is not at all good news. He says, "Today, the ice sheets contribute about a third of all sea-level rise, whereas in the 1990s, their contribution was pretty small at about 5%. This has important implications for the future, coastal flooding and erosion."

This expert is a co-leader of a project named the Ice Sheet Mass Balance Intercomparing Exercise. The shorter form of this project is Imbie.

The project consists of a team of experts who have been studying the polar measurements. They have assistance from observational spacecraft that is storing information for the last three decades.

To observe the changes in the ice sheets, the satellites focus on flow, gravity, and volume.

The report by Imbie on ice melting in Antarctica was published in Nature journal in 2018. They have recently published their report on Greenland this week in the printed edition of the same journal.

The team offers some general remarks by using some of the latest achievements.

Among them, the most important is that the ice loss is beyond expectation if they consider the IPCC's computer model. That means ice is now melting faster than the earlier estimate. 

According to IPCC's report made in 2014 showing the mid-range simulations (RCP4.5) and predicted a 53cm sea-level rise by 2100. But the Imbie team's reports indicate that the ice melts in Greenland and Antarctica will bring forward some other fatal consequences besides adding another 17cm sea-level rising as estimated by the IPCC till the ending of this century.   

Professor Shepherd believes that as a consequence of this ice melting, 400 million people will be the victim of coastal flood at the end of this century.

He says, "What our latest estimates mean is that the timescales people are expecting will be shorter. Whatever town or coastal planning measures you're intending to put in place, they need to be built sooner."

Climate change has its impact across the world, but Greenland and Antarctica are showing different responses to it.

As a consequence of global warming, the ocean water is warming day by day. The warm water of oceans directly touches southern polar ice. The ice can not stand the warm water and starts to melt. The ice located on the edges suffers the most. Apart from the edges, the upper ice of the ice sheets also melt because of the air is also getting warmer.

The 17.8mm rising on the sea-level is a collaboration by the ice melt of Greenland and Antarctica. 10.6mm that is 60% of the total sea-level rise by Greenland ice melting and the rest 40% that will raise the sea-level to 7.2mm is by Antarctica.

The ice loss in the 1990ss in these areas were 81 billion tonnes per year. But the ice loss rate from the 2010s is 475 billion tonnes per year.

The researchers of the Imbie publish the result earlier before the IPCC's so-called Sixth Assessment Report (AR6) due out next year.

According to Prof Shepherd, there are many risks for future intercomparisons because many dedicated satellites may demise in due time, and there will be a lack of proper initiatives to replace them.

Currently, the American space agency's ICESat-2 platform and the European Space Agency's CryoSat-2 satellite are his particular concern.

Both of them can observe the ice sheets than any other related technologies. They do this because they are located on closer orbits of the south and north poles.

He says, "I fear we will soon be back to the situation of the early 2000s when we had to make do with missions that were not really designed to look at polar regions. We'll be doing our best despite the absence of the data we really require - unfortunately. But we've been there before."