Nearly 11,000 square miles, or 28,707 square kilometers, of Greenland’s glaciers and glaciers have melted in the past three decades, according to a comprehensive analysis of historical satellite records. The total area of ​​ice loss is equivalent to the size of Albania and is approximately 1.6% of the total Greenland ice and glacier. Where there was once ice and snow, there are now barren rocks, wetlands and scrublands.

A team of scientists from the University of Leeds who tracked changes in Greenland from the 1980s to the 2010s say that rising air temperatures are causing the ice to retreat, which in turn affects the surface temperature of the land. , greenhouse gas emissions and landscape stability.

Permafrost (the permanently frozen layer beneath the Earth’s surface) is “degrading” due to warming, and scientists warn that in some areas this could affect infrastructure, buildings and the communities on them. The findings were published in the journal “Vegetation-dominated land cover changes in Greenland have doubled in three decades.” Scientific Reports.

Impact of global warming

Greenland is part of the Arctic region. It is the largest island in the world, measuring approximately 836,330 square miles (2.1 million square kilometers). Much of the land is covered by ice and glaciers and is home to approximately 57,000 people.

Since the 1970s, the region has been warming at twice the rate of the global average. The average annual air temperature in Greenland between 2007 and 2012 was 3 °C higher than the 1979-2000 average. And researchers warn that more extreme temperatures are likely in the future.

Jonathan Carriwick, a geoscientist at Leeds School of Environment and one of the authors of the study, said: “Higher temperatures are associated with the land cover changes we see in Greenland.

“By analyzing high-resolution satellite images, we were able to create a detailed record of the land cover changes that occurred.”

Ice disappears, replaced by bare rocks and bushes

Ice loss was concentrated at the margins of modern glaciers and in the north and southwest of Greenland. High levels of ice loss were also observed in some areas in the west, mid-northwest, and southeast. Over three decades, vegetation area increased by 33,774 square miles (87,475 square kilometers), more than doubling the study period.

Significant vegetation growth was observed in the southwest, east and northeast. The largest increase in dense wetland vegetation occurred around Kangerlussuaq in the southwest and some areas in the northeast.

The researchers’ analysis showed that vegetation increased along the latitudinal gradient between 63°N and 69°N and decreased north of it.

Carriwick said: “We have seen signs that ice loss triggers other reactions that will lead to further ice loss and the subsequent ‘greening’ of Greenland, where ice loss exposes exposed bedrock which is then colonized by tundra and eventually shrubs.

“At the same time, water released from melting ice moves sediment and silt, which eventually forms wetlands and marshes.”

Ice loss causes more warming

Ice loss affects the earth’s surface temperature through albedo, a measure of how much the surface reflects light. Snow and ice are good at reflecting solar energy reaching the Earth’s surface, which helps keep the Earth cooler. As the ice retreats, it exposes bedrock that absorbs more solar energy, raising the surface temperature of the land.

Likewise, when the ice melts, the amount of water in the lakes increases. Water absorbs more solar energy than snow, which increases the temperature of the land surface.

greenhouse gas emitter

The analysis shows an almost fourfold increase in Greenland’s wetlands, especially in the east and northeast. Wetlands are the source of methane emissions. In the paper, the researchers noted: “The expansion of vegetation, especially in wetlands, points to thawing of permafrost, active thickening of the layer and thus emissions of greenhouse gases previously stored in these arctic soils.”

The researchers also developed a model to predict which parts of Greenland are likely to experience “significant and accelerated” changes in the future.

The lead author of the report, Dr., who conducted the research as part of his doctorate. Michael Grimes added: “The expansion of vegetation combined with the retreat of glaciers and ice sheets significantly alters the flow of sediments and nutrients in coastal waters.

“These changes are particularly critical for indigenous people whose traditional hunting practices rely on the stability of these fragile ecosystems. “In addition, the loss of Greenland ice pack is a significant contributor to global sea level rise; “This trend poses significant challenges both now and in the future.”