It’s not the first time scientists warn of the impact global warming on the Antarctica. Now two studies by scientists from Jet Propulsion Laboratory from NASA warned of speeding up loss of platforms at Antarctic ice. In addition, they indicated that this situation will affect global sea level riseas The ice sheet of the White Continent “has been losing mass in recent decades” and “the iceberg is breaking off twice as much as previous estimates.”
The first of the works, which was published in the journal Naturethis is luck map where it was shown “how an iceberg break (breaking of ice from an ice front) has changed the Antarctic coastline over the last 25 years” as the edge of the ice sheet split into these frozen shapes “faster than it can be replaced”.
And the second, which was broadcast in Scientific data on the Earth systemshows in great detail how Antarctic ice is thinningas ocean water melted, it spread from the outer edges of the continent inward, almost doubling in the western parts of the ice sheet in the last decade.
resolutely, Chad Greenthe study’s lead author and scientist at the Jet Propulsion Laboratory, described what is happening at the South Pole: “La Antarctica is falling apart“. “As ice shelves shrink and weaken, the continent’s massive glaciers tend to accelerate and increase the rate of global sea level rise.“, – said the expert.
As scientists have warned,most Antarctic glaciers empty into the ocean, where they terminate in floating ice shelves up to 3 kilometers (2 mi) thick and 800 kilometers (500 mi) wide.“, because the “ ice platforms they act like buttresses“these structures”preventing ice from simply sliding into the ocean“.
However, when you education “son stablethey have natural cycle calving and restocking, which keeps its size fairly constant in the long run”, but in recent decades “Ocean warming has been destabilization of Antarctic ice shelves melting them from below, making them more thin at weak“.
To detect this situation on the white continent, the researchers used satellite altimeters that managed to measure the process of ice thinning by measuring its changing height. However, prior to this study, satellite imagery had not been used for this type of analysis because “they were difficult to interpret”.
“For example, you can imagine looking at a satellite image and trying to figure out the difference between a white iceberg, a white ice shelf, white sea ice, and even a white cloud. It has always been a difficult task,” said Green; while noting that “we now have enough data from several satellite sensors to see a clear picture of how Antarctica’s coastline has evolved in recent years.“.
As the experts explained, for this study they synthesized satellite images of the continent “in the visible, infrared, thermal (thermal) and radar wavelengths since 1997”, which further combined these measurements. “With the understanding of ice flow gained from NASA’s ongoing glacier mapping project, they have mapped the edges of ice shelves about 30,000 linear miles (50,000 kilometers) off the Antarctic coast.”
The results alarmed experts, as losses from calving so much exceeded the natural growth of the ice shelf that “Antarctica is unlikely to return to its pre-2000 size by the end of this century.“. Moreover, they assured that this information suggests that “large losses can be expected: the largest ice shelves in Antarctica appear to be approaching major calving events in the next 10 to 20 years.”
In their work, the scientists warned that it’s a “find doubles previous estimates ice loss from floating ice shelves in Antarctica since 1997 from 6 billion to 12 billion metric tons. The loss of ice through calving has weakened ice shelves and allowed Antarctic glaciers to drain faster into the ocean, accelerating the global rate of sea level rise..
As for the second work, which scientists called “additional“, was based on analysis of “nearly 3 billion data points of seven spaceborne altimetry instruments to produce the longest continuous dataset of changes in ice sheet height, an indicator of ice loss, since 1985.” To get this information, The researchers had to “synthesize and analyze huge measurement files into a single high-resolution dataset, requiring many years of work and thousands of hours of computing time on NASA servers.”
To obtain this information, scientists usedradar and laser measurements of ice elevation with centimeter accuracy“, thus they were able to “produce the highest resolution monthly ice loss change maps ever created.” In this sense, they explained that the data they collected allowed them to learn “how long-term trends and annual weather patterns affect the ice”.which also “shows the rise and fall of the ice sheet as subglacial lakes regularly fill and empty miles below the surface.”
“subtle changes such, in combination with better understanding long-term trends in this dataset will help researchers understand the processes that affect ice lossleading to more accurate estimates of sea level rise in the future,” said study lead author and JPL member Johan Nilsson. “Transforming data into something broader and more useful could bring us closer to the breakthroughs needed to better understand our planet and help us prepare for the future impacts of climate change.“, he concluded.