Sensitivity of the Madden Julian Oscillation to Ocean Warming in a Lagrangian Atmospheric Model
Sensitivity of the Madden Julian Oscillation to Ocean Warming in a Lagrangian Atmospheric Model
复制标题
拉格朗日大气模型中马登朱利安振荡对海洋变暖的敏感性
作者：
P. Haertel
马登朱利安振荡（MJO）是热带季节内天气变化的最大贡献者。它与印度洋和西太平洋上空缓慢向东移动的广泛降雨增强区域有关，这对大气环流产生了全球影响。最近的一些观测和模拟研究表明，随着海洋变暖，MJO正在变得越来越强。在这项研究中，作者探讨了最近开发的拉格朗日大气模型（LAM），这已被证明是模拟强大的和现实的MJO在以前的工作中的MJO海洋变暖的敏感性。数值模拟表明，海洋变暖导致更频繁和更强烈的MJO，传播更快，覆盖更大的热带地区。MJO的加强是由于来自温暖的海洋沃茨的水汽通量增强。虽然由于理想化的物理参数化和使用规定的海面温度，LAM模拟有一些局限性，但它们提供了更多的证据，表明如果海洋继续变暖，MJO将加强，它们也揭示了这种加强的机制。
The Madden Julian Oscillation (MJO) is the largest contributor to intraseasonal weather variations in the tropics. It is associated with a broad region of enhanced rainfall that moves slowly eastward over the Indian and western Pacific Oceans, which has global impacts on atmospheric circulations. A number of recent observational and modeling studies have suggested that the MJO is becoming stronger as the oceans warm. In this study, the author explores the sensitivity of the MJO to ocean warming in a recently developed Lagrangian Atmospheric Model (LAM), which has been shown to simulate robust and realistic MJOs in previous work. Numerical simulations suggest that ocean warming leads to more frequent and intense MJOs that propagate more rapidly and cover a larger region of the tropics. The strengthening of the MJO is attributed to enhanced surface fluxes of moisture coming from the warmer ocean waters. While the LAM simulations have a number of limitations owing to idealized physical parameterizations and the use of prescribed sea surface temperatures, they provide additional evidence that the MJO will strengthen if the oceans continue to warm, and they also shed light on the mechanism of this strengthening.