A GPU-based Implementation of WRF PBL/MYNN Surface Layer Scheme

Xianyun Wu, Bormin Huang, Hung-Lung Allen Huang, Mitchell D. Goldberg

Abstract: Nakanishi and Niino proposed an improved Mellor-Yamada (M-Y) Level-3 model (MYNN) surface for three-dimensional simulation of advection fog. The model is on the basis of large-eddy simulation and is numerically stable. The model predicts vertical profiles of mean quantities such as temperature that are in good agreement with those obtained from large-eddy simulation of a radiation fog. In this paper, we accelerate Nakanishi and Niino PBL's Surface Layer scheme in a highly parallel environment, using NVIDIA Graphics Processing Units (GPU). This GPU implementation efficiently utilizes the fine grained parallelism exhibited by the MYNN PBL scheme. The algorithm is accelerated on a low-cost personal supercomputer with over 500 CUDA cores running on a GPU. This implementation achieves a high speedup of 160×.