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Home / Science / Melting Arctic ice is now pouring 14,000 tons of water per second into the ocean, scientists find

Melting Arctic ice is now pouring 14,000 tons of water per second into the ocean, scientists find




A melting iceberg floats along a fjord that moves away from the edge of the Greenland ice cap near Nuuk, Greenland, in 201
1. (Brennan Linsley / AP)

A new scientific survey found that the Arctic glaciers are the largest contributors in the world for raising the level of the sea, eliminating the ice at an accelerated rate that now adds well over one millimeter to the ocean level each year.

This is much more melting ice than the Antarctic is contributing, although the Antarctic contains much more ice. Still, guided by glaciers in Alaska, Canada and Russia, and by the vast expanse of ice in Greenland, the Arctic that heats up quickly overcomes the entire frozen continent to the south – for now.

However, the biggest problem is that both regions appear to accelerate their losses simultaneously – suggesting that we may have an even faster pace of rising sea levels in future decades. The seas are increasing by about three millimeters each year, according to NASA. This is mainly driven by the Arctic contribution, from Antarctica and by a third main factor: ocean water naturally expands while it heats up.

For arctic ice loss, "the rate has tripled since 1986," said Jason Box, first author of the new study and a scientist at the Geological Survey of Denmark and Greenland. "So it clearly shows an acceleration of the contribution at sea level."

"Antarctica will probably take over in the future, but in the last 47 years of this study, it is not controversial that the Arctic is the largest contribution of land ice to raising the level of sea, "he said.

Scientists in the United States, Chile, Canada, Norway and the Netherlands contributed to the work, published in Environmental Research Letters.

Arctic is also losing floating sea ice at a rapid pace, but this loss does not substantially contribute to sea level rise (although it has many other consequences). The losses of sea ice correspond to what is happening on earth, which makes sense because both phenomena are driven by the rapid warming of the atmosphere in the Arctic, which has warmed up at a much faster rate than observed at low latitudes. Even the hot sea is causing part of the ice loss.

Here is the new count of the study of where all Arctic ice losses come from 1971:


J. Box et al., Environmental Research Letters.

The research was performed by combining a highly reliable gravity-based arctic mass loss measurement from NASA's satellites with the oldest direct field measurements taken from the field, dating back to 1971. [19659014] The total loss of Arctic is currently 447 billion tons of ice in the year – that Box has calculated about 14,000 tons of water per second. This is for the period between 2005 and 2015. Between 1986 and 2005, the loss is calculated at around 5,000 tonnes per second – therefore, the rate has almost tripled.

Separate research has recently discovered that the loss rate of the Antarctic has also tripled in just a decade, reaching 219 billion tons annually from 2012 to 2017.

Assuming that these numbers are correct and by summing them together, the polar regions of the world are losing about 666 billion tons of ice to the ocean every year – amounting to a little less than two millimeters of sea level rise each year.

Treating the Arctic as a whole may be missing something, however, notes Christopher Larsen, glacier expert at the University of Alaska at Fairbanks.

The arctic acceleration documented in the study is led by Greenland, which contains more than 20 feet of potential sea level rise, making all other Arctic ice sources pale.

"Compared to the current rate of ic E mass loss, and its increasing percentages, is Greenland which has the most significant rate of increase in mass loss today," Larsen said in a e-mail.

"This is particularly noteworthy since ultimately Greenland has more ice to lose in the northern hemisphere," he said. "With the speed with which the loss of ice is now or could become everywhere in the north, the regional masses of ice mass in Alaska or Arctic Canada are smaller than those that Greenland holds. "

To give a sense of the extent of the Arctic losses, Box figured out what it would mean if they were distributed among the human population of the Earth.

"If you take the 7.7 billion people on Earth and divide the current numbers, from 2005 to 2015, every person on Earth would have the equivalent of 160 liters a day, every day, every year", called Box.

Correction: This story erroneously referred to the letters of the journal Environmental Research as Geophysical Research Letters. This was correct.


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