Estimates of volcanic-induced cooling in the Northern Hemisphere over the past 1,500 years
Estimates of volcanic-induced cooling in the Northern Hemisphere over the past 1,500 years
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DOI：
10.1038/ngeo2526
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发表时间：
2015-10
影响因子：
18.3
通讯作者：
M. Stoffel;M. Khodri;C. Corona;S. Guillet;Virginie Poulain;S. Bekki;J. Guiot;B. Luckman;C. Oppe
中科院分区：
文献类型：
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作者：
M. Stoffel;M. Khodri;C. Corona;S. Guillet;Virginie Poulain;S. Bekki;J. Guiot;B. Luckman;C. Oppe
火山爆发可以改变全球气候，从而引发经济、政治和人口变化。在许多模拟研究和基于树木年轮的半球温度重建中，已经评估了最大的火山事件的气候影响。然而，从气候模式模拟中得到的火山表面冷却比基于树木年轮的代用物中看到的冷却系统地强得多，这表明代用物低估了冷却。和/或模拟的强迫是不切实际的高。在这里，我们利用树木年轮宽度和最大晚木密度重建了北半球过去1500年的夏季温度。我们还模拟了两次大喷发的气候影响，inAD1257和1815，使用一个气候模型，明确说明了自我限制的气溶胶微物理过程。我们的树木年轮重建显示出比低空间覆盖率和仅基于树木年轮宽度的重建更大的冷却，而我们的模拟显示出比以前依赖于约束不佳的喷发季节和排除非线性气溶胶微物理的模拟更少的冷却。我们的树木年轮重建和气候模拟结果是一致的，因为这些火山喷发，北半球热带外夏季的平均温度下降了0.8到1.3摄氏度。这种代理证据和模式证据的协调为改进对过去和未来火山作用在气候强迫中的作用的评估铺平了道路。
Explosive volcanism can alter global climate, and hence trigger economic, political and demographic change,. The climatic impact of the largest volcanic events has been assessed in numerous modelling studies and tree-ring-based hemispheric temperature reconstructions,,,. However, volcanic surface cooling derived from climate model simulations is systematically much stronger than the cooling seen in tree-ring-based proxies, suggesting that the proxies underestimate cooling,; and/or the modelled forcing is unrealistically high. Here, we present summer temperature reconstructions for the Northern Hemisphere from tree-ring width and maximum latewood density over the past 1,500 years. We also simulate the climate effects of two large eruptions, inAD1257 and 1815, using a climate model that accounts explicitly for self-limiting aerosol microphysical processes,. Our tree-ring reconstructions show greater cooling than reconstructions with lower spatial coverage and based on tree-ring width alone, whereas our simulations show less cooling than previous simulations relying on poorly constrained eruption seasons and excluding nonlinear aerosol microphysics. Our tree-ring reconstructions and climate simulations are in agreement, with a mean Northern Hemisphere extra-tropical summer cooling over land of 0.8 to 1.3 °C for these eruptions. This reconciliation of proxy and model evidence paves the way to improved assessment of the role of both past and future volcanism in climate forcing.