Article publicat a l’edició digital del diari The Guardian d’ahir dimarts 27 d’agost.
The world’s most sparsely populated country could be covered by swaths of forests instead of barren ice sheet, experts say
Climate change could bring about the greening of Greenland by the end of the century, scientists predict. Today only four indigenous tree species grow on the island, confined to small areas in the south. Three-quarters of Greenland, the world’s most sparsely populated country, is covered by a barren ice sheet. But by the year 2100 swaths of verdant forest could be covering much of its land surface, according to experts.
“Greenland has .. the potential to become a lot greener”, said lead scientist Professor Jens-Christian Svenning, from Aarhus University in Denmark. “Forest like the coastal coniferous forests in today’s Alaska and western Canada will be able to thrive in fairly large parts of Greenland, for example, with trees like sitka spruce and lodgepole pine”. “It will provide new opportunities for the Greenlanders.”
The research showed that with expected levels of warming a majority of 44 species of North American and European trees and bushes will be able to thrive in Greenland. Many species could already flourish in Greenland today, according to the analysis published in the journal Philosophical Transactions of the Royal Society B.
One reason for the island’s lack of current greenery is the slow speed at which forests expand by themselves. Computer simulations show it could take more than 2,000 years for Greenland’s indigenous trees to spread to every area blessed with a suitable climate in 2100. Despite this handicap, a key species such as the Arctic dwarf birch could be established over more than 400,000sqkm – an area almost the size of Sweden – by the end of the century. The transformation is likely to alter Greenland’s ecosystem, leading to the loss of Arctic animals and plants.
On the other hand there could be significant commercial possibilities linked to forestry, agriculture and tourism. Humans could play an active role in the greening of Greenland by helping to speed up the spread of new plant species, says Prof Svenning. “People will often plant utility and ornamental plants where they can grow; it lies in our human nature,” he said. “Such plantings could get a huge impact on the future Greenlandic nature as a source of dissemination. This certainly has positive aspects.”
A warmer Greenland would also be much more vulnerable to invasive species, he added. “If imports and planting of species will take place without any control you may get a very chaotic and Klondyke-like development,” Prof Svenning warned.