公司鲍名副教授与美国华盛顿大学大气科学系Dennis L. Hartmann教授合作发表在Geophys. Res. Lett. 的论文近期被选为美国地球物理学会研究亮点（AGU research spotlight)。
Bao, M., and D. L. Hartmann (2014), The response to MJO-like forcing in a nonlinear shallow-water model, Geophys. Res. Lett., 41, 1322–1328, doi:10.1002/2013GL057683.
MJO（热带最显著的低频信号）不仅对热带天气气候，而且对热带外天气气候有重要影响；但其机制并不清楚。Bao and Hartmann (2014)利用浅水模式试验揭示了其中关键的动力学过程：亚洲副热带急流的出口区是正压能量转换最大的地区，当热带MJO激发的下游Rossby波信号到达急流出口区，将从急流中的纬向平均动能获得最大的扰动动能，并随着MJO东移而保持准定常特征，从而能够沿着球面向中高纬度传播，这与观测特征非常一致。而过去的观点认为MJO是通过上游Rossby波的传播影响热带外与观测并不相符。该研究结果不仅有助于理解MJO如何影响季节内太平洋-北美遥相关、北美天气气候，而且对理解热带外大气低频振荡以及平流层大气环流持续性异常提供了理论基础。
Eos, Transactions American Geophysical Union的研究亮点报导
http://onlinelibrary.wiley.com/doi/10.1002/2014EO220010/abstract
Title: How the Madden-Julian Oscillation affects North American weather
The unusual weather in the United States during the winter of 2013-2014—when the West stayed hot and dry, the Northeast was battered by Arctic winds, and the South was blanketed in snow—was caused in part by an atmospheric phenomenon that blocked normal weather patterns from reaching the West Coast. The jet stream, forced to flow around a stable high-pressure system, became curvier than normal. Over the eastern Pacific, the jet stream flowed far to the north before turning south over Alaska, bringing cold Arctic air to theMidwest.
The set of atmospheric conditions that caused the curvy jet stream is known as the positive phase of the Pacific-North American pattern (PNA). The PNA cycles intraseasonally and is a strong influence on climate variability in the Northern Hemisphere.
Previous research has showed that the oscillation of the PNA is weakly attributed to the El Ni?o–Southern Oscillation. In a new model simulation, Bao and Hartmann identified a mechanism through which the PNA could also be physically connected to the Madden-Julian Oscillation (MJO), an intraseasonal climate system marked by a migrating heat source that initiates in theIndian Oceanand propagates eastward into the western Pacific.
According to the authors' model, when the migrating MJO heat source is over thePhilippinesandIndonesia, which, in turn, causes a semi-stationary anomaly to form in the jet stream. As the MJO heat source moves into the Pacific, the jet stream anomaly creeps eastward. When the anomaly reaches the westernU.S., it strengthens, setting the stage for the positive phase of the PNA.