DiNezio Pedro N, Puy Martin, Thirumalai Kaustubh, Jin Fei-Fei, Tierney Jessica E
Institute for Geophysics, Jackson School of Geosciences, University of Texas at Austin, J. J. Pickle Research Campus, Building 196, 10100 Burnet Road (R2200), Austin, TX 78758, USA.
Department of Geosciences, The University of Arizona, 1040 E. 4th St., Tucson, AZ 85721, USA.
Sci Adv. 2020 May 6;6(19):eaay7684. doi: 10.1126/sciadv.aay7684. eCollection 2020 May.
Presently, the Indian Ocean (IO) resides in a climate state that prevents strong year-to-year climate variations. This may change under greenhouse warming, but the mechanisms remain uncertain, thus limiting our ability to predict future changes in climate extremes. Using climate model simulations, we uncover the emergence of a mode of climate variability capable of generating unprecedented sea surface temperature and rainfall fluctuations across the IO. This mode, which is inhibited under present-day conditions, becomes active in climate states with a shallow thermocline and vigorous upwelling, consistent with the predictions of continued greenhouse warming. These predictions are supported by modeling and proxy evidence of an active mode during glacial intervals that favored such a state. Because of its impact on hydrological variability, the emergence of such a mode would become a first-order source of climate-related risks for the densely populated IO rim.
目前，印度洋处于一种气候状态，这种状态阻止了逐年的强烈气候变化。在温室变暖的情况下，这种情况可能会改变，但机制仍不确定，从而限制了我们预测未来极端气候事件变化的能力。通过气候模型模拟，我们发现了一种气候变率模式的出现，这种模式能够在整个印度洋产生前所未有的海表温度和降雨波动。这种模式在当前条件下受到抑制，在温跃层较浅和上升流强烈的气候状态下变得活跃，这与持续温室变暖的预测一致。这些预测得到了冰川期活跃模式的模型和代用证据的支持，该模式有利于这种状态。由于其对水文变率的影响，这种模式的出现将成为人口密集的印度洋沿岸与气候相关风险的一级来源。
