Uncertainty Quantification of WRF Model for Rainfall Prediction over the Sichuan Basin, China

The mesoscale Weather Research and Forecasting (WRF) model has been widely employed to forecast day-ahead rainfalls. However, the deterministic predictions from the WRF model incorporate relatively large errors due to numerical discretization, inaccuracies in initial/boundary conditions and paramete...

Full description

Bibliographic Details
Main Authors: Yu Du, Ting Xu, Yuzhang Che, Bifeng Yang, Shaojie Chen, Zhikun Su, Lianxia Su, Yangruixue Chen, Jiafeng Zheng
Format: Article
Language:English
Published: MDPI AG 2022-05-01
Series:Atmosphere
Subjects:
Online Access:https://www.mdpi.com/2073-4433/13/5/838
_version_ 1827670383713583104
author Yu Du
Ting Xu
Yuzhang Che
Bifeng Yang
Shaojie Chen
Zhikun Su
Lianxia Su
Yangruixue Chen
Jiafeng Zheng
author_facet Yu Du
Ting Xu
Yuzhang Che
Bifeng Yang
Shaojie Chen
Zhikun Su
Lianxia Su
Yangruixue Chen
Jiafeng Zheng
author_sort Yu Du
collection DOAJ
description The mesoscale Weather Research and Forecasting (WRF) model has been widely employed to forecast day-ahead rainfalls. However, the deterministic predictions from the WRF model incorporate relatively large errors due to numerical discretization, inaccuracies in initial/boundary conditions and parameterizations, etc. Among them, the uncertainties in parameterization schemes have a huge impact on the forecasting skill of rainfalls, especially over the Sichuan Basin which is located east of the Tibetan Plateau in southwestern China. To figure out the impact of various parameterization schemes and their interactions on rainfall predictions over the Sichuan Basin, the Global Forecast System data are chosen as the initial/boundary conditions for the WRF model and 48 ensemble tests have been conducted based on different combinations of four microphysical (MP) schemes, four planetary boundary layer (PBL) schemes, and three cumulus (CU) schemes, for four rainfall cases in summer. Compared to the observations obtained from the Chinese ground-based and encrypted stations, it is found that the Goddard MP scheme together with the asymmetric convective model version 2 PBL scheme outperforms other combinations. Next, as the first step to explore further improvement of the WRF physical schemes, the polynomial chaos expansion (PCE) approach is then adopted to quantify the impacts of several empirical parameters with uncertainties in the WRF Single Moment 6-class (WSM6) MP scheme, the Yonsei University (YSU) PBL scheme and the Kain-Fritsch CU scheme on WRF rainfall predictions. The PCE statistics show that the uncertainty of the scaling factor applied to ice fall velocity in the WSM6 scheme and the profile shape exponent in the YSU scheme affects more dominantly the rainfall predictions in comparison with other parameters, which sheds a light on the importance of these schemes for the rainfall predictions over the Sichuan Basin and suggests the next step to further improve the physical schemes.
first_indexed 2024-03-10T03:20:16Z
format Article
id doaj.art-3f0a5b05e3b7431186a4f86f3eeebf0b
institution Directory Open Access Journal
issn 2073-4433
language English
last_indexed 2024-03-10T03:20:16Z
publishDate 2022-05-01
publisher MDPI AG
record_format Article
series Atmosphere
spelling doaj.art-3f0a5b05e3b7431186a4f86f3eeebf0b2023-11-23T10:03:39ZengMDPI AGAtmosphere2073-44332022-05-0113583810.3390/atmos13050838Uncertainty Quantification of WRF Model for Rainfall Prediction over the Sichuan Basin, ChinaYu Du0Ting Xu1Yuzhang Che2Bifeng Yang3Shaojie Chen4Zhikun Su5Lianxia Su6Yangruixue Chen7Jiafeng Zheng8College of Atmospheric Science, Chengdu University of Information Technology, Chengdu 610225, ChinaCollege of Atmospheric Science, Chengdu University of Information Technology, Chengdu 610225, ChinaCollege of Atmospheric Science, Chengdu University of Information Technology, Chengdu 610225, ChinaEngineering Practice Center, Chengdu University of Information Technology, Chengdu 610225, ChinaCollege of Atmospheric Science, Chengdu University of Information Technology, Chengdu 610225, ChinaQuanzhou Jinjiang International Airport, Quanzhou 362299, ChinaQuanzhou Jinjiang International Airport, Quanzhou 362299, ChinaCollege of Atmospheric Science, Chengdu University of Information Technology, Chengdu 610225, ChinaCollege of Atmospheric Science, Chengdu University of Information Technology, Chengdu 610225, ChinaThe mesoscale Weather Research and Forecasting (WRF) model has been widely employed to forecast day-ahead rainfalls. However, the deterministic predictions from the WRF model incorporate relatively large errors due to numerical discretization, inaccuracies in initial/boundary conditions and parameterizations, etc. Among them, the uncertainties in parameterization schemes have a huge impact on the forecasting skill of rainfalls, especially over the Sichuan Basin which is located east of the Tibetan Plateau in southwestern China. To figure out the impact of various parameterization schemes and their interactions on rainfall predictions over the Sichuan Basin, the Global Forecast System data are chosen as the initial/boundary conditions for the WRF model and 48 ensemble tests have been conducted based on different combinations of four microphysical (MP) schemes, four planetary boundary layer (PBL) schemes, and three cumulus (CU) schemes, for four rainfall cases in summer. Compared to the observations obtained from the Chinese ground-based and encrypted stations, it is found that the Goddard MP scheme together with the asymmetric convective model version 2 PBL scheme outperforms other combinations. Next, as the first step to explore further improvement of the WRF physical schemes, the polynomial chaos expansion (PCE) approach is then adopted to quantify the impacts of several empirical parameters with uncertainties in the WRF Single Moment 6-class (WSM6) MP scheme, the Yonsei University (YSU) PBL scheme and the Kain-Fritsch CU scheme on WRF rainfall predictions. The PCE statistics show that the uncertainty of the scaling factor applied to ice fall velocity in the WSM6 scheme and the profile shape exponent in the YSU scheme affects more dominantly the rainfall predictions in comparison with other parameters, which sheds a light on the importance of these schemes for the rainfall predictions over the Sichuan Basin and suggests the next step to further improve the physical schemes.https://www.mdpi.com/2073-4433/13/5/838uncertainty quantificationWRF modelSichuan Basinrainfall predictionparameterization schemes
spellingShingle Yu Du
Ting Xu
Yuzhang Che
Bifeng Yang
Shaojie Chen
Zhikun Su
Lianxia Su
Yangruixue Chen
Jiafeng Zheng
Uncertainty Quantification of WRF Model for Rainfall Prediction over the Sichuan Basin, China
Atmosphere
uncertainty quantification
WRF model
Sichuan Basin
rainfall prediction
parameterization schemes
title Uncertainty Quantification of WRF Model for Rainfall Prediction over the Sichuan Basin, China
title_full Uncertainty Quantification of WRF Model for Rainfall Prediction over the Sichuan Basin, China
title_fullStr Uncertainty Quantification of WRF Model for Rainfall Prediction over the Sichuan Basin, China
title_full_unstemmed Uncertainty Quantification of WRF Model for Rainfall Prediction over the Sichuan Basin, China
title_short Uncertainty Quantification of WRF Model for Rainfall Prediction over the Sichuan Basin, China
title_sort uncertainty quantification of wrf model for rainfall prediction over the sichuan basin china
topic uncertainty quantification
WRF model
Sichuan Basin
rainfall prediction
parameterization schemes
url https://www.mdpi.com/2073-4433/13/5/838
work_keys_str_mv AT yudu uncertaintyquantificationofwrfmodelforrainfallpredictionoverthesichuanbasinchina
AT tingxu uncertaintyquantificationofwrfmodelforrainfallpredictionoverthesichuanbasinchina
AT yuzhangche uncertaintyquantificationofwrfmodelforrainfallpredictionoverthesichuanbasinchina
AT bifengyang uncertaintyquantificationofwrfmodelforrainfallpredictionoverthesichuanbasinchina
AT shaojiechen uncertaintyquantificationofwrfmodelforrainfallpredictionoverthesichuanbasinchina
AT zhikunsu uncertaintyquantificationofwrfmodelforrainfallpredictionoverthesichuanbasinchina
AT lianxiasu uncertaintyquantificationofwrfmodelforrainfallpredictionoverthesichuanbasinchina
AT yangruixuechen uncertaintyquantificationofwrfmodelforrainfallpredictionoverthesichuanbasinchina
AT jiafengzheng uncertaintyquantificationofwrfmodelforrainfallpredictionoverthesichuanbasinchina