Low Antarctic continental climate sensitivity due to high ice sheet orography
Low Antarctic continental climate sensitivity due to high ice sheet orography
复制标题
由于冰盖地形较高，南极大陆气候敏感性较低
DOI：
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发表时间：
2020
影响因子：
9
通讯作者：
L. Polvani
中科院分区：
文献类型：
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作者：
Hansi K. A. Singh;L. Polvani
南极大陆在过去的70年里没有变暖，尽管大气中温室气体的浓度在单调地增加。在本文中，我们研究了南极冰盖（AIS）的高地形是否有助于延缓该大陆的变暖。为此，我们对比了南极气候对co2加倍的响应与现今地形与平坦AIS的响应。为了证实我们的发现，我们用两种不同的气候模型进行了这项工作。我们发现，在AIS变平的情况下，co2加倍导致更多的潜热向南极大陆输送，大陆上更大的水汽辐合，从而导致更多的地表放大冷凝加热。湿润等熵面变平使大陆上的水汽更大的辐合成为可能，这降低了沿温带向极地水汽输送主要发生的轨迹的湿度梯度，从而使更多的水汽到达极点。此外，当AIS变平时，极经向环流消失，允许更大的二氧化碳强迫暖温平流流向南极大陆。我们的研究结果表明，目前AIS的高海拔在降低南极大陆对co2强迫变暖的敏感性方面起着重要作用。
The Antarctic continent has not warmed in the last seven decades, despite a monotonic increase in the atmospheric concentration of greenhouse gases. In this paper, we investigate whether the high orography of the Antarctic ice sheet (AIS) has helped delay warming over the continent. To that end, we contrast the Antarctic climate response to CO 2 -doubling with present-day orography to the response with a flattened AIS. To corroborate our findings, we perform this exercise with two different climate models. We find that, with a flattened AIS, CO 2 -doubling induces more latent heat transport toward the Antarctic continent, greater moisture convergence over the continent and, as a result, more surface-amplified condensational heating. Greater moisture convergence over the continent is made possible by flattening of moist isentropic surfaces, which decreases humidity gradients along the trajectories on which extratropical poleward moisture transport predominantly occurs, thereby enabling more moisture to reach the pole. Furthermore, the polar meridional cell disappears when the AIS is flattened, permitting greater CO 2 -forced warm temperature advection toward the Antarctic continent. Our results suggest that the high elevation of the present AIS plays a significant role in decreasing the susceptibility of the Antarctic continent to CO 2 -forced warming.
影响因子：
5.2
作者：
Vargas Zeppetello, L. R.;Donohoe, A.;Battisti, D. S.
通讯作者：
Battisti, D. S.
DOI：
10.1073/pnas.1519132113
发表时间：
2016-02-09
影响因子：
11.1
作者：
Rietbroek, Roelof;Brunnabend, Sandra-Esther;Dahle, Christoph
通讯作者：
Dahle, Christoph