It is not the first time that the scientists warn about the impact of global warming on the Antarctica. Now, two studies by researchers at the Jet Propulsion Laboratory of the POT warned about acceleration in the loss of platforms Y antarctic ice. In addition, they pointed out that this situation will influence the global sea level riseas The White Continent’s ice sheet “has been losing mass in recent decades,” with “iceberg calving double previous estimates.”
The first of the works, which was published in the journal Natureit is a luck of Map where it was shown “how the calving of an iceberg (the detachment of ice from a glacial front) has changed the Antarctic coast in the last 25 years”, being that the edge of the ice sheet separated into these frozen shapes “faster than it can be replaced.”
While the second, which was broadcast in Earth System Science Datashows in great detail “how the Antarctic ice thinningas ocean water melts, it has spread from the outer edges of the continent into its interior, almost doubling in the western parts of the ice sheet in the past decade.
emphatically, Chad Greenelead author of the study and a JPL scientist, described what happens at the South Pole: “Antarctica is falling apart”. “When ice shelves shrink and weaken, the continent’s massive glaciers tend to accelerate and increase the rate of global sea level rise.“, pointed out the expert.
As the scientists warned,most Antarctic glaciers empty into the ocean, where they end in floating ice shelves up to 3 kilometers (2 mi) thick and 800 kilometers (500 mi) wide”, being that “the ice platforms they act like buttresses” of these structures “preventing the ice from simply sliding into the ocean”.
However, when you’re formations “are stablethey have a natural cycle of calving and resupply that maintains its size fairly constant in the long term”, but in the last decades “ocean warming has been destabilizing the Antarctic ice shelves by melting them from below, making them more thin Y weak”.
To detect this situation on the white continent, the researchers used satellite altimeters, which managed to measure the thinning process of the ice by measuring its changing height. However, until this study, satellite images had not been used for this kind of analysis, since “they have been 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. That has always been a difficult task,” said Greene; while he stressed that “we now have enough data from multiple satellite sensors to see a clear picture of how the coastline of Antarctica has evolved in recent years”.
As explained by the experts, for this study they synthesized satellite images of the continent “in visible, infrared thermal (heat), and radar wavelengths from 1997,” further combined these measurements “With an understanding of ice flow gained from an ongoing NASA glacier mapping project, they mapped the edges of ice shelves around 30,000 linear miles (50,000 kilometers) off the Antarctic coast.”
The results alerted experts, as calving losses so far outstripped the natural growth of the ice shelf that “Antarctica is unlikely to be able to grow back to its pre-2000 extent by the end of this century”. What’s more, they assured that this information suggests that “larger losses can be expected: the largest ice shelves in Antarctica appear to be headed for large calving events in the next 10 to 20 years.”
In the work, the scientists warned that this “finding doubles previous estimates of ice loss from the floating ice shelves of Antarctica since 1997, from 6 billion to 12 billion metric tons”, being that Ice loss from calving has weakened ice shelves and allowed Antarctic glaciers to flow more rapidly into the ocean, accelerating the global rate of sea level rise..
As for the second work, which the scientists called “complementary”, was based on analysis of “nearly 3 billion data points of seven space-borne altimetry instruments to produce the longest continuous data set on changing ice sheet height, an indicator of ice loss, since 1985.” To get this information, The researchers had to “synthesize and analyze the massive measurement files into a single high-resolution dataset took years of work and thousands of hours of computing time on NASA servers.”
To obtain this information, the scientists used aradar and laser measurements of ice elevation, accurate to centimeters”, in this way they managed to “produce the monthly maps of ice loss change with the highest resolution ever made”. In this sense, they explained that the data 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 like these, in combination with a better understanding of long-term trends in this data set will help researchers understand the processes that influence ice loss, which will lead to better future estimates of sea level rise,” said study lead author and JPL member Johan Nilsson. “Condensing data into something more broadly useful can bring us closer to the breakthroughs we need to better understand our planet and help us prepare for the future impacts of climate change.“, he concluded.