Heubel Sina, Rammig Anja, Buras Allan
Land Surface-Atmosphere Interactions, TU Munich, Freising, Germany.
Department of Environmental Systems Science, Institute of Terrestrial Ecosystems, ETH Zurich, Zurich, Switzerland.
Glob Chang Biol. 2025 Apr;31(4):e70185. doi: 10.1111/gcb.70185.
Forest tree species are expected to experience a substantial redistribution due to climate change. While previous work has emphasized the effects of a warmer and drier climate on European tree-species distributions, to date no study has investigated the potential impact of a collapse of the Atlantic Meridional Overturning Circulation (AMOC). Here, we deploy climate-envelope models to quantile mapped, high-resolution (1km) CMIP6 climate projections and compare tree-species distributions under an active AMOC vs. an inactive AMOC scenario. Across Europe, our tree-species projections indicate contrasting impacts of the two scenarios. In Scandinavia, many of the currently abundant tree species were projected a dramatic decline and partial disappearance due to the strong cooling under an inactive AMOC. In Central and Southern Europe, however, some of the currently abundant species suffered less under an inactive AMOC compared to an active AMOC scenario while others-such as the economically important species of Norway spruce-almost went extinct. As opposed to the classic climate-change scenario supporting Mediterranean species in Central Europe, projected European tree-species portfolios consisted of a higher share of boreal, cold-tolerant species in the inactive AMOC scenario. Finally, tree-species diversity was projected to decline even stronger under an inactive vs. an active AMOC scenario. Altogether, while an AMOC collapse may locally result in more favorable conditions for specific species in comparison to a classic climate-change scenario, the dramatic economic and ecological consequences suggested by our projections indicate the urgent need for climate-change mitigation to lower the likelihood of an AMOC collapse.
由于气候变化，预计森林树种将经历大规模重新分布。虽然此前的研究强调了气候变暖和变干对欧洲树种分布的影响，但迄今为止，尚无研究调查大西洋经向翻转环流（AMOC）崩溃的潜在影响。在此，我们将气候包络模型应用于分位数映射的高分辨率（1公里）CMIP6气候预测，并比较活跃AMOC情景与不活跃AMOC情景下的树种分布。在整个欧洲，我们对树种的预测表明这两种情景的影响截然不同。在斯堪的纳维亚半岛，由于不活跃AMOC下的强烈降温，许多目前丰富的树种预计将急剧减少并部分消失。然而，在中欧和南欧，一些目前丰富的物种在不活跃AMOC下比活跃AMOC情景下遭受的影响更小，而其他物种——如经济上重要的挪威云杉——几乎灭绝。与支持中欧地中海物种的经典气候变化情景相反，在不活跃AMOC情景下，预计欧洲树种组合中北方耐寒物种的比例更高。最后，预计在不活跃AMOC情景下，树种多样性的下降甚至会比活跃AMOC情景下更强烈。总之，虽然与经典气候变化情景相比，AMOC崩溃可能会在局部地区为特定物种带来更有利的条件，但我们的预测所表明的巨大经济和生态后果表明，迫切需要减缓气候变化以降低AMOC崩溃的可能性。
