Exploring the impacts of physics and resolution on aqua‐planet simulations from a nonhydrostatic global variable‐resolution modeling framework

Journal of Advances in Modeling Earth Systems

Jinho Yoon¹  Chun Zhao¹  Samson Hagos¹  Bryce E. Harrop¹  Koichi Sakaguchi¹  L. Ruby Leung¹  Jian Lu¹  William Skamarock²  Michael G. Duda²  Sang‐Hun Park² 

[1] Atmospheric Sciences and Global Change Division, Pacific Northwest National LaboratoryRichland Washington USA;National Center for Atmospheric ResearchBoulder Colorado USA;

关键词: nonhydrostatic;    MPAS;    resolution sensitivity;    CAM5;    CAM4;   

DOI  :  10.1002/2016MS000727

来源: DOAJ

【 摘 要 】

Abstract The nonhydrostatic Model for Prediction Across Scales (NH‐MPAS) provides a global framework to achieve high resolution using regional mesh refinement. Previous studies using the hydrostatic version of MPAS (H‐MPAS) with the physics parameterizations of Community Atmosphere Model version 4 (CAM4) found notable resolution‐dependent behaviors. This study revisits the resolution sensitivity using NH‐MPAS with both CAM4 and CAM5 physics. A series of aqua‐planet simulations at global quasiuniform resolutions and global variable resolution with a regional mesh refinement over the tropics are analyzed, with a primary focus on the distinct characteristics of NH‐MPAS in simulating precipitation, clouds, and large‐scale circulation features compared to H‐MPAS‐CAM4. The resolution sensitivity of total precipitation and column integrated moisture in NH‐MPAS is smaller than that in H‐MPAS‐CAM4. This contributes importantly to the reduced resolution sensitivity of large‐scale circulation features such as the intertropical convergence zone and Hadley circulation in NH‐MPAS compared to H‐MPAS. In addition, NH‐MPAS shows almost no resolution sensitivity in the simulated westerly jet, in contrast to the obvious poleward shift in H‐MPAS with increasing resolution, which is partly explained by differences in the hyperdiffusion coefficients used in the two models that influence wave activity. With the reduced resolution sensitivity, simulations in the refined region of the NH‐MPAS global variable resolution configuration exhibit zonally symmetric features that are more comparable to the quasiuniform high‐resolution simulations than those from H‐MPAS that displays zonal asymmetry in simulations inside the refined region. Overall, NH‐MPAS with CAM5 physics shows less resolution sensitivity compared to CAM4.

【 授权许可】

Unknown