Antarctic experts warned that the Denman Glacier in Antarctica may be much more vulnerable than previously estimated, and it may tend to separate in the future.
Global climate change is developing in a direction beyond human expectations, and the tipping point of Antarctic ecology may come early!
Antarctica Denman Glacier
Denman Glacier/Antarctica Denman Glacier is located in the east of Antarctica, with a length of about 110 kilometers and a width of about 11-16 kilometers. It is injected into the Shackleton Ice Shelf east of David Island.
This glacier is quite huge. If all of it melts, the global sea level will rise. 1.5 m. The future trends of Denman Glacier have a great impact on the Earth’s climate.
Researchers at the University of California, Irvine, and NASA’s Jet Propulsion Laboratory are very concerned that the terrain under the ice sheet could cause the Denman Glacier to collapse.
Therefore, they investigated and evaluated, the results of the evaluation were published as an article in the “Geophysical Research Letters” on March 23.
Antarctica Denman Glacier melting
The assessment shows that between 1979 and 2017, the glacier lost more than 268 billion tons of ice due to melting or fracture.
It is not just temperature that caused a large amount of ice loss, because there is no ridge protection in the west of Denman Glacier and the steep ground Extending to 3.2 kilometers below the sea surface, here is not only the melting area of the Denman Glacier,
but also the turbulent currents will cause the glacier to break away and become icebergs wandering around in the Antarctic waters.
Unlike other Antarctic glaciers where the tongues of ice tend to be stable, the tongues of ice from the Denman Glacier extend into the sea.
The UCI and the NASA Jet Propulsion Laboratory accurately analyzed the melting speed of the Denman Glacier based on COSMO-SkyMed satellite images. About 3 meters of ice are lost every year!
According to the assessment of the researchers, the Denman Glacier has receded by about 5 kilometers in the past 22 years.
This is an alarming rate, and the speed will accelerate due to climate warming.
Based on this, it is estimated that the Denman Glacier will disappear completely within the next 100 years, and the sea level will rise by 1.5 meters, coupled with the greenhouse effect, the global sea level will rise 2.4 meters by 2100!
Also, according to two studies in the journal Nature, the current Antarctic ice sheet is melting 6 times faster than in the 1990s.
Based on the data on the loss of Antarctic and Greenland glaciers, the IPCC (Intergovernmental Panel on Climate Change) has issued a very severe warning: If carbon emissions are not reduced quickly, By the end of this century, rising sea levels will affect 400 million people!
How serious are the consequences of global warming and the disappearance of glaciers?
From the perspective of climate change in geological history, the glacial period and the interglacial period are intersecting. The current interglacial period is in the interglacial period, which is the warmest time.
The current interglacial period began at the end of the Pleistocene 11,400 years ago. The interglacial period is approximately keep it for 20,000 years, and there may be an ice age of 70-80,000 years in the future!
The causes of the glacial period are very complicated, and there has always been no unified statement, but human activities may change the law of the glacial period.
According to a report from the World Meteorological Organization in early March, the global temperature has risen by 1.1℃ since the Industrial Revolution.
Which means that the global temperature has reached 50% of the 2°C target that 195 countries signed the Paris Climate Agreement in 2015!
The agreement stipulates that governments should work hard to reduce emissions and control global warming by 2100 at the level before the industrial revolution.
Because the global temperature rise will cause sea level rise, extreme heat waves and draughts, cause social unrest, and then threaten the survival of mankind!
UN experts stated in the latest report of the WMO that the world is deviating from the track determined by the “Paris Climate Agreement”!
How serious are the consequences?
The first thing is that the coastal areas will inundate a lot of land due to sea-level rise. For example, a global sea-level rise of 2.4 meters may affect the livelihoods of one billion people!
Comparison of Rotterdam and New York After the world has risen by 2 meters, the Netherlands is all underwater.
New York is relatively less affected. Of course, the entire country of the Netherlands is at sea level or even below, so some low-lying countries will face the disaster of extinction!
Arctic tundra melting
There is no permafrost in the Antarctic, but there are large areas of Arctic tundra near the North Pole. Russia, Alaska and Canada have large areas of Arctic tundra.
The spring season is a paradise for migratory birds. The melting of the tundra will cause a large amount of methane to be released into the atmosphere, and the greenhouse effect of methane.
It is 25 times that of carbon dioxide, so the future situation will be very touching. The earth will enter the devil’s cycle!
Evidently, don’t forget there is an infection that exposed animal carcasses after the tundra melted in Russia in the past few years. This is the anthrax virus.
The unusually warm temperature between 2004 and 2009 led to the epidemic of marine mammal distemper virus near the Arctic.
These are all warnings from nature to mankind! Drought and fire The monsoon rains after the African drought in 2018 awakened the locust eggs sleeping in the Arabian Peninsula.
After two generations of development in the southern uninhabited lands, they began to migrate, then all over the Arabian Peninsula and western Africa, Somalia, Ethiopia and Kenya, and eastern Iran, India, and Pakistan have suffered unprecedented locust invasions and gluttonous locust plague.
The locust invasion has not ended for almost two years… If it is not controlled, a new wave of locust plagues will form in the next April-June.
Beginning in 2019, Australian fires have been burning for more than half a year. Although it is difficult to determine whether it caused by climate warming, drought is the most obvious factor, and global warming will exacerbate this process.
Australian fires will continue to worry about in the future. Of course, with the advent of the dry season, the Amazon rainforest fire index has risen sharply.
According to the assessment of environmental protection organizations, the probability of an Amazon prairie in the next 50-100 years is high.
Losses due to climate-related insurance catastrophes from 1997 to 2016 (US$ billion) The ecological tipping point has arrived early The ecological tipping point is a tipping point at which the ecological environment can be restored on its own.
The earth is a super large ecology, which is composed of various small ecological areas, and the ice sheet is the fuse that triggers this ecological balance explosion. If it is lost, the situation facing mankind in the future will be grim!
Morlighem, M., Rignot, E., Binder, T., Blankenship, D., Drews, R., Eagles, G., Eisen, O., Ferraccioli, F., Forsberg, R., Fretwell, P. and Goel, V., 2020. Deep glacial troughs and stabilizing ridges unveiled beneath the margins of the Antarctic ice sheet. Nature Geoscience, 13(2), pp.132-137.