Holocene dynamics of the Southern Hemisphere westerly winds and possible links to CO2 outgassing
Holocene dynamics of the Southern Hemisphere westerly winds and possible links to CO2 outgassing
复制标题
南半球西风的全新世动态及其与二氧化碳排放的可能联系
作者：
K. Saunders;S. Roberts;Bianca B. Perren;C. Butz;L. Sime;S. Davies;Wim Van Nieuwenhuyze;M. Grosjean;D. Hodgson
南半球西风对南大洋碳汇能力具有重要的调节作用。它们调节富碳深水的涌升，并与海冰一起决定可用于气-海气体交换的海洋表面积。一些模型表明，目前这些风的加强和向极的转移将削弱碳汇。如果正确的话，百年到千年尺度的SHW强度重建应该与过去大气CO2，温度和海冰的变化联系起来。在这里，我们提出了一个12,300年的风强度重建的基础上三个独立的代理人，跟踪海盐气溶胶和矿化颗粒在亚南极麦夸里岛湖泊沉积物中积累的输入。在大约1.21万年前（ka）和11.2 ka之间，以及大约7 ka以来，风强度高于其长期平均值，并与大气CO2的增加相对应。相反，从约11.2至7.2万年，风强度低于其长期平均值，并对应于减少大气中的CO2。这些意见是一致的模型推断增强SHW有助于长期的CO2从南大洋的出气。南半球西风的强度在整个全新世变化，根据重建湖泊沉积物，与更强的风符合较高的大气CO2水平的时期。
The Southern Hemisphere westerly winds (SHW) play an important role in regulating the capacity of the Southern Ocean carbon sink. They modulate upwelling of carbon-rich deep water and, with sea ice, determine the ocean surface area available for air–sea gas exchange. Some models indicate that the current strengthening and poleward shift of these winds will weaken the carbon sink. If correct, centennial- to millennial-scale reconstructions of the SHW intensity should be linked with past changes in atmospheric CO2, temperature and sea ice. Here we present a 12,300-year reconstruction of wind strength based on three independent proxies that track inputs of sea-salt aerosols and minerogenic particles accumulating in lake sediments on sub-Antarctic Macquarie Island. Between about 12.1 thousand years ago (ka) and 11.2 ka, and since about 7 ka, the wind intensities were above their long-term mean and corresponded with increasing atmospheric CO2. Conversely, from about 11.2 to 7.2 ka, the wind intensities were below their long-term mean and corresponded with decreasing atmospheric CO2. These observations are consistent with model inferences of enhanced SHW contributing to the long-term outgassing of CO2 from the Southern Ocean.The strength of the Southern Hemisphere westerly winds varied throughout the Holocene, according to a reconstruction from lake sediments, with periods of stronger winds coincident with higher atmospheric CO2 levels.
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影响因子：
4.3
作者：
L. Sime;D. Hodgson;T. Bracegirdle;C. Allen;Bianca B. Perren;S. Roberts;A. M. Boer
通讯作者：
L. Sime;D. Hodgson;T. Bracegirdle;C. Allen;Bianca B. Perren;S. Roberts;A. M. Boer
影响因子：
56.9
作者：
Lamy, F;Kaiser, J;Stoner, J
通讯作者：
Stoner, J
影响因子：
4
作者：
Brovkin, Victor;Bruecher, Tim;Jensen, Dorthe Dahl
通讯作者：
Jensen, Dorthe Dahl
影响因子：
18.3
作者：
Lamy, Frank;Kilian, Rolf;Steinke, Tatjana
通讯作者：
Steinke, Tatjana
影响因子：
4.4
作者：
Bracegirdle, Thomas J.;Shuckburgh, Emily;Wilcox, Laura J.
通讯作者：
Wilcox, Laura J.