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Greenland’s ice melting shows unsettling variations

A recent study has revealed a link between an abnormal seasonal ice melting in Greenland and how earth’s poles warm faster than the rest of the planet.

The phenomenon is known as Arctic amplification. It was first witnessed back in 2015 over Greenland. Arctic amplification is the succession of events in the increased speed of the Arctic’s rise in temperature compared to the rest of the planet. The event that revealed its existence were the variations in the Greenland’s atmospheric jet streams that occur due to seasonal melting. The jet streams reached latitudes that have never been seen before.

Greenland ice canyon filled with melt water in summer 2010.Ian Joughin Credit: University of Washington APL Polar Science Center

How Greenland’s ice affects everyone

The melting of Greenland’s ice is necessary, as it has direct implications on average global sea level. If all of Greenland’s ice were to melt, the sea level would rise 7 meters, causing catastrophic changes in many human settlements and every coastal environment known to humanity. Researchers noted that last year’s melting process was particularly important, due to an increased amount of melting in the northern portion of the country.

When ice melts, there is a much broader area of water that’s able to take in sunlight, thus accelerating warming due to radiation. One of the most important indicators of Greenland’s ice melting is an atmospheric jet stream that changes its behavior depending on how the ice has been melting. The difference in temperature between the tropics and the poles is reducing, which will divert into a slowing but stronger jet stream. Warmer winds are also heading up north, which is a common sight, but for 2015 the jet stream had gone farther north than ever.

It appears that it is all part of a climate change loop, as Northern Greenland has seen less snow throughout these last years, which contributes towards the country’s ability of solar radiation absorption.

The winds of Northern Greenland have shown significant variations too. The winds that usually blew from east to west are blowing from west to east. On the other hand, the southern part of the country saw nearly the inverse then the north, as there was a higher rate of snow and a lesser degree of melting when compared to previous seasons.

The planet’s poles temperatures see faster changes

Although the researchers are inclined into pointing Arctic amplification as the main reason behind the unprecedented warming rates, previous research has predicted that the witnessed events were to be expected. Said analysis was performed by professors from the University of Wisconsin, back in 2012.

Polar amplification takes into account the effects of radiation as it produces changes in a planet’s temperature when compared to the rest of the atmosphere. The phenomenon is closely linked to pressure anomalies, which have been proven to be connected to the irregular flow of the Greenland jet stream.

The random stationary high-pressure locations have been measured for 165 years, and the 11 most severe events have occurred since 2007 onward. It was stated by researchers that there is a clear indication of a link between the latest high-pressure blocks and the increasing temperatures in the area. They expect more record Greenland was melting episodes over the following years.

The affluence of the jet stream is thought to be of high impact on climate change. The predicted rise in temperature for the last half-century has been off 4 °C, but this rate of change may increase due to Arctic amplification.

It is also important to note that the Arctic sea ice has reached its lowest point in several years. What the melting would be like in 2016, researchers can’t tell, but they can assure that in the next couple of years humans might delve into “uncharted territory,” as our species have not lived similar conditions anytime in the past. This year’s meeting in early April is comparable to April 2012, which sets a likely scenario where record melts may occur once again.

The researchers’ insight

Study co-author Thomas Mote warned that 2015 contained extensive melting in the northern part of Greenland, which is a very unusual event. This was most likely caused by the variations on the jet stream. He also stressed the importance of the Greenland ice sheet, as it has become one of the main natural contributors to the increasing of sea level since the year 2000.

Water coming from the melting of Greenland’s ice layers has been proved to affect the circulation of oceanic waters and the distribution of temperature. Although the researchers have solid ground to understand the recent events, this is the first time where they have witnessed an increased rate of melting in the northern part of the country. Mote commented that they still do not completely understand the implications of an increased melting in Northern Greenland.

Lead author Marco Tedesco said that the way Greenland’s ice melts has a significant impact on climate change. Tedesco, a professor of Columbia University and NASA, questioned that “if the loss of sea ice is driving shifts in the jet stream, the jet stream is changing Greenland, and this, in turn, has an impact on the Arctic system as well as the climate. It’s a system, it is strongly interconnected, and we have to approach it as such.”

Source: Nature Communications

Categories: Science
Daniel Francis: Guitarist, destroyer of worlds. Columnist at Ultimate-Guitar.com
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