Land cover changes across Greenland dominated by a doubling of vegetation in three decades
Scientific Reports volume 14, Article number: 3120 (2024 ) Cite this article
Land cover responses to climate change must be quantified for understanding Arctic climate, managing Arctic water resources, maintaining the health and livelihoods of Arctic societies and for sustainable economic development. This need is especially pressing in Greenland, where climate changes are amongst the most pronounced of anywhere in the Arctic. Ice loss from the Greenland Ice Sheet and from glaciers and ice caps has increased since the 1980s and consequently the proglacial parts of Greenland have expanded rapidly. Here we determine proglacial land cover changes at 30 m spatial resolution across Greenland during the last three decades. Besides the vastly decreased ice cover (− 28,707 km2 ± 9767 km2), we find a doubling in total areal coverage of vegetation (111% ± 13%), a quadrupling in wetlands coverage (380% ± 29%), increased meltwater (15% ± 15%), decreased bare bedrock (− 16% ± 4%) and increased coverage of fine unconsolidated sediment (4% ± 13%). We identify that land cover change is strongly associated with the difference in the number of positive degree days, especially above 6 °C between the 1980s and the present day. Contrastingly, absolute temperature increase has a negligible association with land cover change. We explain that these land cover changes represent local rapid and intense geomorphological activity that has profound consequences for land surface albedo, greenhouse gas emissions, landscape stability and sediment delivery, and biogeochemical processes.
The Arctic has been warming at double the global mean rate since the 1970s1. Some of the most pronounced recent warming has been across Greenland, where mean annual air temperatures between 2007 and 2012 were 3 °C warmer compared to the 1979–2000 average2. More extremes of temperature and precipitation are expected in the near future as Greenland’s climate resilience decreases and non-linear land-climate system feedbacks develop3, including soil development and vegetation change, land surface albedo change, and permafrost degradation. The environmental impacts of Arctic climate change are most obviously manifest in Greenland’s abundant, expanding and rapidly-evolving proglacial landscapes4. Specifically, Greenland’s glaciers and ice caps (GICs) are shrinking, glacier-fed lakes are expanding, permafrost lakes are draining, rivers are transporting vast amounts of sediment and aggrading and widening, and vegetation cover and species diversity is expanding, largely coincident with Arctic shrubification5,6,7,8,9,10,11,12.
