Preliminary evaluation of MJO simulation in GAMIL3 (Grid-point atmospheric model of IAP LASG)

ABSTRACT

This study evaluates the performance of the Grid-point Atmospheric Model of IAP LASG, version 3 (GAMIL3), in simulating the Madden–Julian Oscillation (MJO), based on the CMIP6 (phase 6 of the Coupled Model Intercomparison Project) AMIP (Atmospheric Model Intercomparison Project) simulation. Results show that GAMIL3 reasonably captures the main features of the MJO, such as the eastward-propagating signal in the MJO frequency band, the symmetric and asymmetric structures of the MJO, several convectively coupled equatorial waves, and the MJO life cycle. However, GAMIL3 underestimates the MJO amplitude, especially for outgoing longwave radiation, as do most CMIP5 models, and simulates slow eastward propagation.

GRAPHICAL ABSTRACT

摘要

本文以第六次国际耦合模式比较计划（CMIP6）的 大气模式比较（AMIP）试验结果为基础，评估了中国科学院大气物理研究所LASG国家重点实验室所研发的新版本格点大气环流模式GAMIL3对MJO的模拟性能。结果表明：GAMIL3合理地捕捉了MJO的主要特征，如MJO向东传播的信号、MJO的对称和非对称结构、几种对流耦合的赤道波动以及MJO的生命周期。然而，正如大多数CMIP5模型一样GAMIL3低估了MJO的振幅，和东传速度。

KEYWORDS:

• MJO
• GAMIL3
• evaluation

关键词:

• 热带季节内振荡
• 格点大气环流模式
• 模式评估

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study was jointly supported by the National Key Research and Development Program of China [grant number 2017YFA0603903] and the National Natural Science Foundation of China [grant numbers 41622503 and 41775101].