Modeling El Niño and its tropical teleconnections during the last glacial‐interglacial cycle
Modeling El Niño and its tropical teleconnections during the last glacial‐interglacial cycle
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DOI：
10.1029/2003gl018553
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发表时间：
2003-12
影响因子：
5.2
通讯作者：
B. Otto‐Bliesner;E. Brady;Sang‐Ik Shin;Zhengyu Liu;C. Shields
中科院分区：
文献类型：
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作者：
B. Otto‐Bliesner;E. Brady;Sang‐Ik Shin;Zhengyu Liu;C. Shields
NCAR气候系统模型（CSM）是一个全球性的海洋-大气-海冰耦合模型，对末次冰期-间冰期循环的模拟重现了最近的估计，基于烯酮和Mg/Ca比值，热带太平洋的海表面温度（SST）变化和梯度，并预测与全新世相比，厄尔尼诺/拉尼娜现象较弱，而末次冰期最大期（LGM）的厄尔尼诺/拉尼娜现象较强。末次盛冰期（全新世）的变化可追溯到热带太平洋纬向SST梯度的减弱（加强），风应力，上升流和热带温跃层的锐化（减弱）。结果表明，代理证据较弱的降水变化在新几内亚和厄瓜多尔的解释，不仅在厄尔尼诺/拉尼娜现象的变化，但也在大气环流和水文循环的变化。
Simulations with the NCAR Climate System Model (CSM), a global, coupled ocean‐atmosphere‐sea ice model, for the last glacial‐interglacial cycle reproduce recent estimates, based on alkenones and Mg/Ca ratios, of sea surface temperature (SST) changes and gradients in the tropical Pacific and predict weaker El Niños/La Niñas compared to present for the Holocene and stronger El Niños/La Niñas for the Last Glacial Maximum (LGM). Changes for the LGM (Holocene) are traced to a weakening (strengthening) of the tropical Pacific zonal SST gradient, wind stresses, and upwelling and a sharpening (weakening) of the tropical thermocline. Results suggest that proxy evidence of weaker precipitation variability in New Guinea and Ecuador are explained not only by changes in El Niño/La Niña but also changes in the atmospheric circulation and hydrologic cycle.