Science and Tech

Great Icebergs landslides have not increased

Great Icebergs landslides have not increased

Madrid, Jan. 29 (Europa Press) –

While there has been a wide loss of ice platforms in Antarctica due to heating, frequency and size of icebergs landslides It has not changed significantly.

This is what a study conducted by geologists and geographers of the University of Floridawhich has thrown new light on the effects of climate change on the ice platforms of Antarctica.

“Our results suggest that the main threat to our ice platforms is the ‘death for a thousand cuts’ through small detachments, instead of catastrophic extremes,” he said In a statement The attached teacher of Geological Sciences Emma Mackie, co -author of the study, published in Geophysical Research Letters.

Ice detachment, when ice pieces detach from ice platforms and form icebergs, is common and increasingly influenced by climate change. In the case of extremely large icebergs, this process is usually slow and usually start with small cracks that extend through the ice platform before detaching themselves.

These cracks can be detected as they are formed and grow using satellite data, but their random nature and the risks associated with the sending of scientists to observe them in person They make it extremely difficult to predict when future cracks or detachment events can occur.

Important detachment events are particularly difficult to study. While the little ones occur frequently, large events (in which more than 100 square kilometers of ice emerge) are exceptionally rare.

This study is the first of its kind that focuses on these great events. Even with 47 years of satellite data from 1976 to 2023, the team still faced a small sample size. This challenge was addressed with the theory of extreme value, a type of statistical analysis used when studying rare natural disasters such as large earthquakes, extreme floods or volcanic eruptions. As an expert in extreme flooding, co -author Kate Serafin, an attached geography teacher was no stranger to this type of data analysis.

“Statistical models that relate the size and frequency of events are tools that have been used for decades to estimate rare flood events, as a flood that occurs every 100 years“He said.” Now that satellite images can trace great birth events more consistently, we thought we would try if we could apply the same tools to understand how likely these mass birth events are. “

Using this method, the team analyzed extreme detachment events found in the satellite registry and developed a model to predict the probability of these events over time. When creating their models, the researchers also developed scenarios to predict how big the birth events could be.

According to your estimates, An iceberg that is formed once every decade could have a size of up to 6,100 square kilometersjust a little larger than an extreme detachment that occurred in 2017, when an iceberg approximately the size of aceware detached from the Antarctic ice layer. A phenomenon that occurs once every century could produce an iceberg of about 45,000 square kilometersa little bigger than all Denmark.

“An iceberg that appears once every century would be several times larger than any other registered by observations and would have a significant impact on the stability of the ice layer and the oceanic processes,” Mackie said.

The team did not find evidence that the large icebergs have increased in size during the last half century, and that the maximum surface areas of the icebergs occurred between 1986 and 2000. This indicates that extreme detachment events do not correlate with the climate change, although the general loss of the ice platform has increased due to climate change.

While extreme detachment events continue to be rare and can be part of a larger natural cycle, smaller detachment events have dominated the loss of the Antarctic ice platform during the last half century.

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