Assessing climate impacts and risks of ocean albedo modification in the Arctic
Assessing climate impacts and risks of ocean albedo modification in the Arctic
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DOI：
10.1002/2015jc011433
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发表时间：
2016-05-01
影响因子：
3.6
通讯作者：
Oschlies, A.
中科院分区：
文献类型：
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作者：
Mengis, N.;Martin, T.;Oschlies, A.
冰反照率反馈是全球变暖背景下北高纬度地区气温加速升高的关键因素之一。本研究评估了理想化北冰洋反照率修改（AOAM）（一种拟议的气候工程方法）在具有不同代表性浓度路径（RCP）情景的瞬态气候变化模拟过程中的气候影响和风险。我们发现，在大气二氧化碳浓度增加的情况下，所有评估的北极气候指标都没有逆转趋势的潜力。 AOAM 仅在实施后的头几年产生初始抵消。然而，在 RCP8.5(RCP4.5) 情景中，海冰损失可能会推迟 25(60) 年，而 AOAM 模拟中永久冻土的延迟融化可阻止 2100 年释放多达 40(32) Pg 的碳。AOAM 最初抑制了大西洋经向翻转的衰退，并延迟了 RCP 下北欧海域公海深对流的开始。场景。相对于默认的 RCP 模拟，这两个过程都会在 AOAM 模拟中引起地下变暖信号，并有可能破坏北极海洋天然气水合物的稳定。此外，在 2100 年，RCP8.5 AOAM 模拟在许多气候指标中比没有 AOAM 的 RCP4.5 模拟偏离 2005-2015 年参考状态更多。考虑到已证明的风险，我们得出的结论是，在较长的时间范围内，减少排放仍然是防止北极发生严重变化的最安全、最有效的方法。
The ice albedo feedback is one of the key factors of accelerated temperature increase in the high northern latitudes under global warming. This study assesses climate impacts and risks of idealized Arctic Ocean albedo modification (AOAM), a proposed climate engineering method, during transient climate change simulations with varying representative concentration pathway (RCP) scenarios. We find no potential for reversing trends in all assessed Arctic climate metrics under increasing atmospheric CO2 concentrations. AOAM only yields an initial offset during the first years after implementation. Nevertheless, sea ice loss can be delayed by 25(60) years in the RCP8.5(RCP4.5) scenario and the delayed thawing of permafrost soils in the AOAM simulations prevents up to 40(32) Pg of carbon from being released by 2100. AOAM initially dampens the decline of the Atlantic Meridional Overturning and delays the onset of open ocean deep convection in the Nordic Seas under the RCP scenarios. Both these processes cause a subsurface warming signal in the AOAM simulations relative to the default RCP simulations with the potential to destabilize Arctic marine gas hydrates. Furthermore, in 2100, the RCP8.5 AOAM simulation diverts more from the 2005-2015 reference state in many climate metrics than the RCP4.5 simulation without AOAM. Considering the demonstrated risks, we conclude that concerning longer time scales, reductions in emissions remain the safest and most effective way to prevent severe changes in the Arctic.