Computer simulations indicate that only strong climate protections could safeguard about 30 percent of the Siberian tundra to endure into the middle of this century. In other, less favorable scenarios, this vast and unique habitat could vanish entirely. The study, conducted by researchers from the Alfred Wegener Institute, has just been published in eLife.
The Arctic feels the climate crisis most acutely. Over the past five decades, average air temperatures there have risen by more than two degrees Celsius, a rise unmatched elsewhere on the planet. If serious steps are taken to curb greenhouse gas emissions, Arctic warming could be limited to just under 2 degrees Celsius by the end of the century.
Model-based projections show that continued high emissions could drive a sharp uptick in average summer temperatures in the Arctic, potentially reaching up to 14 degrees Celsius above the current 2100 baseline.
Researchers in the study, including Ulrike Herzschuh and Stefan Kruse from the Alfred Wegener Institute, note the impact on both the sea and land. A warming trend will threaten the Arctic Ocean and sea ice while the terrestrial landscape faces dramatic changes. The tree line is already shifting, and it is expected to move northward rapidly in the near future.
The tundra supports a distinct plant community, with about five percent of species being endemic to the Arctic. Typical residents include mountain oats, Arctic poppies, and willow and birch trees, all adapted to short summers and harsh winters. The region also shelters rare wildlife such as reindeer, lemmings, and Arctic insects like wasps.
For their simulation, Herzschuh and AWI modeler Stefan Kruse employed the AWI LAVESI vegetation model. LAVESI distinguishes itself by enabling a view of the entire tree line at the level of individual trees, offering a detailed lens on how the landscape responds to a warming climate, Kruse explains.
Stepping onto the Siberian tundra, the study shows the life cycle of Siberian larches in the transition zone—from seed production and distribution to germination and mature trees. This model helps researchers visualize the progression of the tree line as the climate warms.
The findings are clear: larch forests could advance northward at a rate of up to 30 kilometers per decade. Conversely, large swaths of tundra, unable to migrate to cooler regions due to the adjacent Arctic Ocean, would shrink further.
Under most scenarios, less than six percent of today’s tundra would remain by the middle of the century, while preserving roughly 30 percent would require ambitious greenhouse gas reductions and sustained policy action.
In some regions, Siberia’s 4,000-kilometer uninterrupted tundra belt would be interrupted by a 2,500-kilometer gap between the western Taimyr Peninsula and the eastern Chukotka Peninsula. Even if atmospheric cooling occurred later in the millennium, forests would not fully reclaim former tundra areas.
For further context, the study is referenced in the eLife publication: the journal entry number 75163.
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