Quantifying physical parameterization uncertainties associated with land-atmosphere interactions in the WRF model over Amazon

2021 ◽  
pp. 105761
Author(s):  
Chen Wang ◽  
Yun Qian ◽  
Qingyun Duan ◽  
Maoyi Huang ◽  
Zhao Yang ◽  
...  
2021 ◽  
Vol 11 (23) ◽  
pp. 11221
Author(s):  
Ji Won Yoon ◽  
Sujeong Lim ◽  
Seon Ki Park

This study aims to improve the performance of the Weather Research and Forecasting (WRF) model in the sea breeze circulation using the micro-Genetic Algorithm (micro-GA). We found the optimal combination of four physical parameterization schemes related to the sea breeze system, including planetary boundary layer (PBL), land surface, shortwave radiation, and longwave radiation, in the WRF model coupled with the micro-GA (WRF-μGA system). The optimization was performed with respect to surface meteorological variables (2 m temperature, 2 m relative humidity, 10 m wind speed and direction) and a vertical wind profile (wind speed and direction), simultaneously for three sea breeze cases over the northeastern coast of South Korea. The optimized set of parameterization schemes out of the WRF-μGA system includes the Mellor–Yamada–Nakanishi–Niino level-2.5 (MYNN2) for PBL, the Noah land surface model with multiple parameterization options (Noah-MP) for land surface, and the Rapid Radiative Transfer Model for GCMs (RRTMG) for both shortwave and longwave radiation. The optimized set compared with the various other sets of parameterization schemes for the sea breeze circulations showed up to 29 % for the improvement ratio in terms of the normalized RMSE considering all meteorological variables.


2016 ◽  
Vol 9 (2) ◽  
pp. 368
Author(s):  
Ricardo Antonio Mollmann Junior ◽  
Rita De Cassia Marques Alves ◽  
Gabriel Bonow Muchow ◽  
Bruno Dias Rodrigues ◽  
Rosiberto Salustiano da Silva Junior ◽  
...  

O objetivo do presente do estudo foi observar a sensibilidade das parametrizações do modelo WRF ao quantificar as variáveis em superfície: pressão atmosférica, temperatura do ar, umidade relativa e precipitação durante o Inverno de 2014 no Estado do Rio Grande do Sul (RS). Os resultados foram demonstrados a partir de análise dos índices estatísticos, bias e Raiz do Erro Quadrático Médio (REQM), quando calculados para comparações entre os dados extraídos de 6 experimentos de simulações do modelo WRF com dados de estações de monitoramento do Instituto Nacional de Meteorologia (INMET) no RS. Os experimentos foram configurados com diferentes parametrização físicas, para assim poder verificar qual combinação apresenta melhor desempenho na representação das condições de Inverno do RS. A partir do reconhecimento das diferentes interpretações físicas que cada conjunto de parametrização pode representar, foi apresentado um estudo de caso afim de diagnosticar as precipitações ocorridas no Estado, principalmente no município de Irai-RS. As análises partiu de um acompanhamento de evento de chuvas ocorrido entre os dias 25 e 30 de junho de 2014, utilizando-se de cartas dos campos meteorológicos de Linhas de Corrente em 850hPa e Precipitação. Percebeu-se que tanto temperatura quanto pressão, o bias e o REQM obtiveram diferenças não significativas entre os experimentos. A UR, no cálculo do bias mostrou uma grande diferença entre os experimentos, devido a forma de seu cálculo considerar apenas o erros sistemáticos, podendo haver cancelamento de erros entre subestimativas e superestimativas. A REQM para a mesma variável, mostrou que os experimentos não se diferenciaram em valores significativos, obtendo apenas nos experimentos 3 e 5, menor valor de erro em comparação aos outros experimentos (~2%). Ao tecer considerações sobre a precipitação, o bias diagnosticou subestimativas nos experimentos para as chuvas durante o inverno de 2014, entretanto no cálculo da REQM os experimentos não tiveram assentimento entre si, exceto o 4 e o 6, onde os valores dos erros totais ficaram inferiores à 2mm. Para o estudo de caso, onde foi acompanhado as chuvas ocorridas durante a passagem de um fenômeno Ciclone Extratropical, em todos os experimentos mostrou a caracterização do evento de precipitação. Com isso, ao diagnosticar a quantidade de precipitação durante o evento ocorrido sobre a estação meteorológica de Irai-RS com os dados do modelo, somado as análises estatísticas, o experimento 6 dentre as combinações de parametrizações apresentadas neste estudo, obteve o melhor desempenho para caracterizar o estado atmosférico durante o período de inverno no RS.   ABSTRACT The objective of this study is to observe the sensitivity of parameterizations of the WRF model to quantify the variables in surface: atmospheric pressure, air temperature, relative humidity and precipitation during the winter of 2014 in the State of Rio Grande do Sul (RS).  The results were demonstrated from analysis of statistical indices, bias and Mean Squared Error root (RMSE) calculated for comparisons between the data extracted from 6 experiments of the WRF model simulations with data from the National Institute of Meteorology monitoring stations (INMET) in RS. The experiments were configuring with different physical parameterization, so that it may examine what combination performs better in the representation of the RS winter conditions. From the recognition of different physical interpretations that each set of parameterization can represent, a case study was made in order to diagnose the precipitations that occurred in the State, mainly in the municipality of Irai. The analysis came from a monitoring rain event occurred between 25 and 30 June 2014, using meteorological fields of 850hPa stream lines and rainfall. However, realizes that both temperature as pressure, the bias and the RMSE obtained no significant differences between experiments. UR, in the calculation of bias showed a big difference between the experiments, because of the manner of calculation only considers the systematic errors, which may cause cancellation of errors between underestimation and overestimation. The RMSE for the same variable showed no differences in significant amounts in the experiments, only in experiments 3 and 5, smallest error value when compared to the other experiments (~ 2%). To develop some considerations on the precipitation, the bias diagnosed underestimates the experiments for the rains during the winter of 2014; however, in the calculation of RMSE the experiments had not consent to each other, except 4 and 6, where the values of total errors were lower to 2mm. For the case study, which was accompanied rainfall occurred during the passage of an extratropical cyclone, in all experiments showed the characterization of the precipitation event. Thus, to diagnose the amount of precipitation during the event occurring on the Irai weather station with model data, combined with statistical analysis, the experiment 6 from the parameterization of combinations shown in this study had the best performance to characterize the atmospheric state during the winter period in the RS. Keywords: Weather numerical forecast, WRF, physical parameterization, atmospheric modeling.   


2021 ◽  
Vol 13 (22) ◽  
pp. 4556
Author(s):  
Dongmei Xu ◽  
Xuewei Zhang ◽  
Hong Li ◽  
Haiying Wu ◽  
Feifei Shen ◽  
...  

In this study, the case of super typhoon Lekima, which landed in Jiangsu and Zhejiang Province on 4 August 2019, is numerically simulated. Based on the Weather Research and Forecasting (WRF) model, the sensitivity experiments are carried out with different combinations of physical parameterization schemes. The results show that microphysical schemes have obvious impacts on the simulation of the typhoon’s track, while the intensity of the simulated typhoon is more sensitive to surface physical schemes. Based on the results of the typhoon’s track and intensity simulation, one parameterization scheme was further selected to provide the background field for the following data assimilation experiments. Using the three-dimensional variational (3DVar) data assimilation method, the Microwave Humidity Sounder-2 (MWHS-2) radiance data onboard the Fengyun-3D satellite (FY-3D) were assimilated for this case. It was found that the assimilation of the FY-3D MWHS-2 radiance data was able to optimize the initial field of the numerical model in terms of the model variables, especially for the humidity. Finally, by the inspection of the typhoon’s track and intensity forecast, it was found that the assimilation of FY-3D MWHS-2 radiance data improved the skill of the prediction for both the typhoon’s track and intensity.


2017 ◽  
Vol 74 (1) ◽  
pp. 43-66 ◽  
Author(s):  
JV Ratnam ◽  
SK Behera ◽  
R Krishnan ◽  
T Doi ◽  
SB Ratna

Atmosphere ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 459
Author(s):  
Abubakar Lungo ◽  
Sangil Kim ◽  
Meiyan Jiang ◽  
Giphil Cho ◽  
Yongkuk Kim

Precipitation prediction is important to help mitigate the effects of drought and floods on various social and economic activities. This research is to improve the forecasting skill over Tanzania by providing suitable combinations of physical parameterization schemes and horizontal grid spacing of the Weather Research Forecasting (WRF) model for daily forecasting over Tanzania. The performance of different schemes on the precipitation systems during the wet and dry seasons over Tanzania is evaluated such that the sensitivity tests was performed for the WRF model at different horizontal resolutions, and for different physical parameterization schemes (convective and cloud microphysics). The results showed that the improved grid spacing was better at completing forecasts during the wet season, but had little significant impacts during the dry season. Model simulations with combinations of Lin et al. microphysics and the multiscale Kain–Fritsch scheme showed greater success during the both seasons; therefore, these combinations were recommended for Tanzania to resolve weather systems during the wet and dry season simulations, respectively.


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