Cold Tropical Pacific Sea Surface Temperatures During the Late Sixteenth-Century North American Megadrought
Cold Tropical Pacific Sea Surface Temperatures During the Late Sixteenth-Century North American Megadrought
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十六世纪末北美特大干旱期间热带太平洋寒冷海面温度
DOI：
10.1029/2018jd029323
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发表时间：
2018
期刊：
影响因子：
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通讯作者：
Coats, Sloan
中科院分区：
文献类型：
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作者：
Cook, Benjamin I.;Williams, A. Park;Smerdon, Jason E.;Palmer, Jonathan G.;Cook, Edward R.;Stahle, David W.;Coats, Sloan
16世纪后期北美的超级风暴在中世纪气候异常期间的超级风暴活动的主要间隔之后的持续性、范围、强度和发生率方面值得注意。热带太平洋的海面温度（SST）强迫被认为是特大干旱的可能驱动因素，我们使用墨西哥和澳大利亚两个新的600年水文气候场重建来研究16世纪后期事件的这一假设。这些重建所代表的地区与热带太平洋SST有很强的遥相关性，证明了每个地区的主要主成分解释了当地水文气候变化的40%，并与北方冬季（12月至1月至2月）NINO 3.4指数显着相关。使用这两个主成分作为预测因子，我们开发了一个巧妙的重建12月-1月-2月的NINO 3.4指数。重建结果显示，16世纪末的大风暴可能发生在过去600年（1566-1590 C.E.;中位NINO 3.4 =-0.79 K）。这段异常寒冷的时期与澳大利亚卡蒂·坦达湖-艾尔湖的一次主要填充事件相吻合，这是一种与重建的SST状态动态一致的水文气候响应。这些结果提供了新的证据，表明热带太平洋强迫是世纪后期北美大规模影响西南部和墨西哥的重要驱动力，突出了气候系统内可能发生的大幅度自然变率。
The late 16th‐century North American megadrought was notable for its persistence, extent, intensity, and occurrence after the main interval of megadrought activity during the Medieval Climate Anomaly. Forcing from sea surface temperatures (SSTs) in the tropical Pacific is considered a possible driver of megadroughts, and we investigate this hypothesis for the late 16th‐century event using two new 600‐year long hydroclimate field reconstructions from Mexico and Australia. Areas represented by these reconstructions have strong teleconnections to tropical Pacific SSTs, evidenced by the leading principal component in each region explaining ∼40% of local hydroclimate variability and correlating significantly with the boreal winter (December‐January‐February) NINO 3.4 index. Using these two principal components as predictors, we develop a skillful reconstruction of the December‐January‐February NINO 3.4 index. The reconstruction reveals that the late 16th‐century megadrought likely occurred during one of the most persistent and intense periods of cold tropical Pacific SST anomalies of the last 600 years (1566–1590 C.E.; median NINO 3.4 = −0.79 K). This anomalously cold period coincided with a major filling episode for Kati Thanda‐Lake Eyre in Australia, a hydroclimate response dynamically consistent with the reconstructed SST state. These results offer new evidence that tropical Pacific forcing was an important driver of the late 16th‐century North American megadrought over the Southwest and Mexico, highlighting the large amplitude of natural variability that can occur within the climate system.