Pub Date : 2021-01-01DOI: 10.46267/j.1006-8775.2021.035
Zhong Shui-xin, Zhuang Yan, Hu Sheng, Chen Zi-tong, Ding Wei-yu, Feng Ye-rong, Deng Tao, Liu Xian-tong, Zhang Yan-xia, XU Dao-sheng, Dai Guang-feng, Meng Wei-guang
{"title":"Verification and Assessment of Real-time Forecasts of Two Extreme Heavy Rain Events in Zhengzhou by Operational NWP Models","authors":"Zhong Shui-xin, Zhuang Yan, Hu Sheng, Chen Zi-tong, Ding Wei-yu, Feng Ye-rong, Deng Tao, Liu Xian-tong, Zhang Yan-xia, XU Dao-sheng, Dai Guang-feng, Meng Wei-guang","doi":"10.46267/j.1006-8775.2021.035","DOIUrl":"https://doi.org/10.46267/j.1006-8775.2021.035","url":null,"abstract":"","PeriodicalId":17432,"journal":{"name":"热带气象学报","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70476560","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.46267/j.1006-8775.2021.030
Z. Zhao-rong, Xue Ji-shan, Shen Xue-shun, Liang Xing-liang
{"title":"Implementation of CMA-GFS 3D-Var System on the Yin-Yang Grid","authors":"Z. Zhao-rong, Xue Ji-shan, Shen Xue-shun, Liang Xing-liang","doi":"10.46267/j.1006-8775.2021.030","DOIUrl":"https://doi.org/10.46267/j.1006-8775.2021.030","url":null,"abstract":"","PeriodicalId":17432,"journal":{"name":"热带气象学报","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70476506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.46267/j.1006-8775.2021.028
Chen Zi-tong, Dai Guang-feng, Wu Kai-xin, Zhong Shui-xin, XU Dao-sheng
{"title":"Development of 1km-Scale Operational Model in South China","authors":"Chen Zi-tong, Dai Guang-feng, Wu Kai-xin, Zhong Shui-xin, XU Dao-sheng","doi":"10.46267/j.1006-8775.2021.028","DOIUrl":"https://doi.org/10.46267/j.1006-8775.2021.028","url":null,"abstract":"","PeriodicalId":17432,"journal":{"name":"热带气象学报","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70476500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.46267/j.1006-8775.2021.033
J. Ming, Fu Liu, Han Zhang
{"title":"Impact of Surface Exchange Coefficients and Sea Surface Cooling on Tropical Cyclone Simulation","authors":"J. Ming, Fu Liu, Han Zhang","doi":"10.46267/j.1006-8775.2021.033","DOIUrl":"https://doi.org/10.46267/j.1006-8775.2021.033","url":null,"abstract":"","PeriodicalId":17432,"journal":{"name":"热带气象学报","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70476546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-01DOI: 10.46267/j.1006-8775.2020.041
Qingyuan Wang, Li Yan, Qingquan Li, Wang Yan
Based on the daily OISST V2 with 0.25o horizontal resolutions, the present study looks into the variations of sea surface temperature (SST) extremes in the China Seas for different segments of the period 1982-2013. The two segments include the warming acceleration period from 1982 to 1997 and the hiatus period from 1998 to 2013 when the global mean surface temperature (GMST) did not significantly increase as expected, or even decreased in some areas. First, we construct the regional average time series over the entire China Seas (15°-45°N, 105°-130°E) for these SST extremes. During the hiatus period, the regionally averaged 10th, 1th and 0.1th percentile of SSTs in each year decreased significantly by 0.40℃, 0.56℃ and 0.58℃ per decade, respectively. The regionally averaged 90th, 99th and 99.9th percentile of SSTs in each year decreased slightly or insignificantly. Our work confirm that the regional hiatus was primarily reflected by wintertime cold extremes. Spatially, the trends of cold extremes in different intensity were non-uniformly distributed. Cold extremes in the near-shore areas were much more sensitive to the global warming hiatus. Hot extremes exhibited non-significant trend in the China Seas during the hiatus period. In short, the variations of the SST extremes in the two periods were non-uniform spatially and asymmetric seasonally. It is unexpected that the hot and cold extremes of each year during 1998-2013 were still higher than those extremes during 1982-1997. It is obvious that compared with the warming acceleration period, hot extremes were far more likely to occur in the recent hiatus as a result of a 0.3℃ warmer shift in the mean temperature distribution. Moreover, hot extremes in the China Seas will be sustained or amplified with the end of warming hiatus and the continuous anthropogenic warming.
{"title":"Sea Surface Temperature Extremes of Different Intensity in the China Seas During the Global Warming Acceleration and Hiatus Periods","authors":"Qingyuan Wang, Li Yan, Qingquan Li, Wang Yan","doi":"10.46267/j.1006-8775.2020.041","DOIUrl":"https://doi.org/10.46267/j.1006-8775.2020.041","url":null,"abstract":"Based on the daily OISST V2 with 0.25o horizontal resolutions, the present study looks into the variations of sea surface temperature (SST) extremes in the China Seas for different segments of the period 1982-2013. The two segments include the warming acceleration period from 1982 to 1997 and the hiatus period from 1998 to 2013 when the global mean surface temperature (GMST) did not significantly increase as expected, or even decreased in some areas. First, we construct the regional average time series over the entire China Seas (15°-45°N, 105°-130°E) for these SST extremes. During the hiatus period, the regionally averaged 10th, 1th and 0.1th percentile of SSTs in each year decreased significantly by 0.40℃, 0.56℃ and 0.58℃ per decade, respectively. The regionally averaged 90th, 99th and 99.9th percentile of SSTs in each year decreased slightly or insignificantly. Our work confirm that the regional hiatus was primarily reflected by wintertime cold extremes. Spatially, the trends of cold extremes in different intensity were non-uniformly distributed. Cold extremes in the near-shore areas were much more sensitive to the global warming hiatus. Hot extremes exhibited non-significant trend in the China Seas during the hiatus period. In short, the variations of the SST extremes in the two periods were non-uniform spatially and asymmetric seasonally. It is unexpected that the hot and cold extremes of each year during 1998-2013 were still higher than those extremes during 1982-1997. It is obvious that compared with the warming acceleration period, hot extremes were far more likely to occur in the recent hiatus as a result of a 0.3℃ warmer shift in the mean temperature distribution. Moreover, hot extremes in the China Seas will be sustained or amplified with the end of warming hiatus and the continuous anthropogenic warming.","PeriodicalId":17432,"journal":{"name":"热带气象学报","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73077545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-01DOI: 10.46267/j.1006-8775.2020.036
Yu Jinnan, Song Li-li, Chen Wen-chao, Zhi Shi-qun, Bian Xueyan, Liu Chun-xia, Huangfu Hui-jun
To investigate the values of 10-m drag coefficient (CD) in different coastal areas under the influence of tropical cyclones, the present study used the observational data from four towers in different coastal areas of the South China Sea (SCS) during six tropical cyclone (TC) passages, and employed the eddy covariance method and the flux profile method. The analysis of footprint showed that the fluxes at Zhizai Island (ZZI), Sanjiao Island (SJI) and Donghai Island (DHI) were influenced basically by the ocean, and the flux at Shangyang Town (SYT) was influenced mainly by the land. The results showed that the dependence relationships of CD on 10-m wind speed (U10) in four different coastal areas under the influence of TCs were different. CD at ZZI and SJI initially increased and then decreased as U10 increased, similar to the pattern over the ocean. CD at ZZI and SJI represented the values over shallow water with seawater depths of ~7 m and ~2 m, respectively. Moreover, the critical wind speed at which CD peaked gradually decreased as the seawater depth became shallower in the coastal areas. CD at DHI and SYT decreased monotonously as U10 increased, similar to the pattern over the land. CD at DHI represented the value over the transition zone from shallow water to coastal land, and CD at SYT represented the value over the coastal land. Meanwhile, the eddy covariance method and the flux profile method were compared at ZZI and SYT during TC passages. It was found that their CD values obtained by the two methods were close. Finally, the parameterizations of observed u* and CD as a function of U10 over four different coastal areas were given under the influence of high winds. These parameterizations of observed CD may be used in high-resolution numerical models for landfalling TC forecast.
{"title":"Characteristics of Drag Coefficient in Different Coastal Regions of the South China Sea Under Tropical Cyclones–An Observational Study","authors":"Yu Jinnan, Song Li-li, Chen Wen-chao, Zhi Shi-qun, Bian Xueyan, Liu Chun-xia, Huangfu Hui-jun","doi":"10.46267/j.1006-8775.2020.036","DOIUrl":"https://doi.org/10.46267/j.1006-8775.2020.036","url":null,"abstract":"To investigate the values of 10-m drag coefficient (CD) in different coastal areas under the influence of tropical cyclones, the present study used the observational data from four towers in different coastal areas of the South China Sea (SCS) during six tropical cyclone (TC) passages, and employed the eddy covariance method and the flux profile method. The analysis of footprint showed that the fluxes at Zhizai Island (ZZI), Sanjiao Island (SJI) and Donghai Island (DHI) were influenced basically by the ocean, and the flux at Shangyang Town (SYT) was influenced mainly by the land. The results showed that the dependence relationships of CD on 10-m wind speed (U10) in four different coastal areas under the influence of TCs were different. CD at ZZI and SJI initially increased and then decreased as U10 increased, similar to the pattern over the ocean. CD at ZZI and SJI represented the values over shallow water with seawater depths of ~7 m and ~2 m, respectively. Moreover, the critical wind speed at which CD peaked gradually decreased as the seawater depth became shallower in the coastal areas. CD at DHI and SYT decreased monotonously as U10 increased, similar to the pattern over the land. CD at DHI represented the value over the transition zone from shallow water to coastal land, and CD at SYT represented the value over the coastal land. Meanwhile, the eddy covariance method and the flux profile method were compared at ZZI and SYT during TC passages. It was found that their CD values obtained by the two methods were close. Finally, the parameterizations of observed u* and CD as a function of U10 over four different coastal areas were given under the influence of high winds. These parameterizations of observed CD may be used in high-resolution numerical models for landfalling TC forecast.","PeriodicalId":17432,"journal":{"name":"热带气象学报","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77921171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-01DOI: 10.46267/j.1006-8775.2020.028
Shi Dan-dan, Rong Yan-shu, Lyu Xing-yue, WU Fu-ting
The Walker circulation (WC) has always been an important issue in atmospheric science research due to the association between the WC and tropical Pacific sea surface temperature (SST), and between the WC and ENSO events. In this paper, a new index-Omega index (OMGI)-is constructed for WC characterization based on the NCEP /NCAR reanalysis data of monthly mean vertical velocity in recent 70 years (1948-2017). Results show that the OMGI can accurately depict the variation characteristics of WC on seasonal, annual and decadal time-scales. There is a significant inverse correlation between the OMGI and equatorial eastern and central Pacific SST. Meanwhile, the peak of the OMGI appears ahead of the ENSO peak, and therefore is able to reflect the SST in the equatorial Pacific. Especially, in 35 ENSO events, the peak of the OMGI appears earlier than Nino 3.4 index for 19 times with 2.6 months ahead on average. In 16 El Nino events, the peak of the OMGI occurs ahead of the El Nino for 9 times with 4 months ahead on average. In 19 La Nina events, the OMGI peak arises 10 times earlier than the La Nina peak, with an average of 1.4 months ahead. OMGI shows obvious leading effect and stability over ENSO events with different strengths and types of single peak and multi peaks: the peak of the OMGI keeps about 2-3 months ahead of the ENSO. Compared with other WC indexes such as UWI and SPLI, OMGI has some advantages in the ability to describe WC changes and present the probability and the time of prediction of ENSO event peaks.
{"title":"A New Index About the Walker Circulation","authors":"Shi Dan-dan, Rong Yan-shu, Lyu Xing-yue, WU Fu-ting","doi":"10.46267/j.1006-8775.2020.028","DOIUrl":"https://doi.org/10.46267/j.1006-8775.2020.028","url":null,"abstract":"The Walker circulation (WC) has always been an important issue in atmospheric science research due to the association between the WC and tropical Pacific sea surface temperature (SST), and between the WC and ENSO events. In this paper, a new index-Omega index (OMGI)-is constructed for WC characterization based on the NCEP /NCAR reanalysis data of monthly mean vertical velocity in recent 70 years (1948-2017). Results show that the OMGI can accurately depict the variation characteristics of WC on seasonal, annual and decadal time-scales. There is a significant inverse correlation between the OMGI and equatorial eastern and central Pacific SST. Meanwhile, the peak of the OMGI appears ahead of the ENSO peak, and therefore is able to reflect the SST in the equatorial Pacific. Especially, in 35 ENSO events, the peak of the OMGI appears earlier than Nino 3.4 index for 19 times with 2.6 months ahead on average. In 16 El Nino events, the peak of the OMGI occurs ahead of the El Nino for 9 times with 4 months ahead on average. In 19 La Nina events, the OMGI peak arises 10 times earlier than the La Nina peak, with an average of 1.4 months ahead. OMGI shows obvious leading effect and stability over ENSO events with different strengths and types of single peak and multi peaks: the peak of the OMGI keeps about 2-3 months ahead of the ENSO. Compared with other WC indexes such as UWI and SPLI, OMGI has some advantages in the ability to describe WC changes and present the probability and the time of prediction of ENSO event peaks.","PeriodicalId":17432,"journal":{"name":"热带气象学报","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49438601","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-28DOI: 10.16555/J.1006-8775.2020.003
Zhong Shuixin, Chen Zi-tong
This paper aims to assess the performances of different model initialization conditions (ICs) and lateral boundary conditions between two global models (GMs), i. e., the European Centre for Medium-Range Weather Forecasts (ECMWF) and National Centers for Environmental Prediction (NCEP), on the accuracy of the Global / Regional Assimilation and Prediction System (GRAPES) forecasts for south China. A total of 3-month simulations during the rainy season were examined and a specific case of torrential rain over Guangdong Province was verified. Both ICs exhibited cold biases over south China, as well as a strong dry bias over the Pearl River Delta (PRD). In particular, the ICs from the ECMWF had a stronger cold bias over the PRD region and a more detailed structure than NCEP. In general, the NCEP provided a realistic surface temperature compared to the ECMWF over south China. Moreover, GRAPES initialized by the NCEP had better simulations of both location and intensity of precipitation than by the ECWMF. The results presented in this paper could be used as a general guideline to the operational numerical weather prediction that uses regional models driven by the GMs.
{"title":"A STUDY ON THE PREDICT ABILITY OF GRAPES MODEL OVER SOUTH CHINA: COMPARISONS BY TWO INITIALIZATION CONDITIONS BETWEEN ECMWF AND NCEP","authors":"Zhong Shuixin, Chen Zi-tong","doi":"10.16555/J.1006-8775.2020.003","DOIUrl":"https://doi.org/10.16555/J.1006-8775.2020.003","url":null,"abstract":"This paper aims to assess the performances of different model initialization conditions (ICs) and lateral boundary conditions between two global models (GMs), i. e., the European Centre for Medium-Range Weather Forecasts (ECMWF) and National Centers for Environmental Prediction (NCEP), on the accuracy of the Global / Regional Assimilation and Prediction System (GRAPES) forecasts for south China. A total of 3-month simulations during the rainy season were examined and a specific case of torrential rain over Guangdong Province was verified. Both ICs exhibited cold biases over south China, as well as a strong dry bias over the Pearl River Delta (PRD). In particular, the ICs from the ECMWF had a stronger cold bias over the PRD region and a more detailed structure than NCEP. In general, the NCEP provided a realistic surface temperature compared to the ECMWF over south China. Moreover, GRAPES initialized by the NCEP had better simulations of both location and intensity of precipitation than by the ECWMF. The results presented in this paper could be used as a general guideline to the operational numerical weather prediction that uses regional models driven by the GMs.","PeriodicalId":17432,"journal":{"name":"热带气象学报","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2020-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87279377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Persistent Heavy Rainfall (PHR) is the most influential extreme weather event in Asia in summer, and thus it has attracted intensive interests of many scientists. In this study, operational global ensemble forecasts from China Meteorological Administration(CMA) are used, and a new verification method applied to evaluate the predictability of PHR is investigated. A metrics called Index of Composite Predictability (ICP) established on basic verification indicators, i. e., Equitable Threat Score(ETS) of 24h accumulated precipitation and Root Mean Square Error(RMSE) of Height at 500hPa, are selected in this study to distinguish“good”and“poor”prediction from all ensemble members. With the use of the metrics of ICP, the predictability of two typical PHR events in June 2010 and June 2011 is estimated. The results show that the“good member”and“poor member”can be identified by ICP and there is an obvious discrepancy in their ability to predict the key weather system that affects PHR.“Good member”shows a higher predictability both in synoptic scale and mesoscale weather system in their location, duration and the movement. The growth errors for “poor” members is mainly due to errors of initial conditions in northern polar region. The growth of perturbation errors and the reason for better or worse performance of ensemble member also have great value for future model improvement and further research.
{"title":"A COMBINED VERIFICATION METHOD FOR PREDICTABILITY OF PERSISTENT HEAVY RAINFALL EVENTS OVER EAST ASIA BASED ON ENSEMBLE FORECAST","authors":"Wu Zhi-peng, Chen Jing, Zhang Han-bin, Chen Fa-jing, Zhuang Xiao-ran","doi":"10.16555/J.1006-8775.2020.004","DOIUrl":"https://doi.org/10.16555/J.1006-8775.2020.004","url":null,"abstract":"Persistent Heavy Rainfall (PHR) is the most influential extreme weather event in Asia in summer, and thus it has attracted intensive interests of many scientists. In this study, operational global ensemble forecasts from China Meteorological Administration(CMA) are used, and a new verification method applied to evaluate the predictability of PHR is investigated. A metrics called Index of Composite Predictability (ICP) established on basic verification indicators, i. e., Equitable Threat Score(ETS) of 24h accumulated precipitation and Root Mean Square Error(RMSE) of Height at 500hPa, are selected in this study to distinguish“good”and“poor”prediction from all ensemble members. With the use of the metrics of ICP, the predictability of two typical PHR events in June 2010 and June 2011 is estimated. The results show that the“good member”and“poor member”can be identified by ICP and there is an obvious discrepancy in their ability to predict the key weather system that affects PHR.“Good member”shows a higher predictability both in synoptic scale and mesoscale weather system in their location, duration and the movement. The growth errors for “poor” members is mainly due to errors of initial conditions in northern polar region. The growth of perturbation errors and the reason for better or worse performance of ensemble member also have great value for future model improvement and further research.","PeriodicalId":17432,"journal":{"name":"热带气象学报","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2020-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86304812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-01DOI: 10.16555/J.1006-8775.2020.006
Wu Hai-ying, Zeng Ming-jian, Mei Haixia, Zhang Bing
In order to study the impacts of wind field variations in the middle and lower troposphere on the development and structure of storms, we carried out numerical experiments on cases of severe convection in the Jianghuai area under the background of cold vortex on April 28, 2015. The results show that the structure and development of convective storms are highly sensitive to the changes of wind fields, and the adjustment of wind fields in the middle or lower troposphere will lead to significant changes in the development and structure of storms. When the wind field in the middle or lower troposphere is weakened, the development of convective storms attenuates to some extent compared with that in the control experiment, and the ways of attenuation in the two experiments are different. In the attenuation test of wind field at the middle level, convective storms obviously weaken at all stages in its development, while for the wind field at the low level, the convective storms weaken only in the initial stage of storm. On the contrary, the enhancement of the wind field in the middle or lower troposphere is conducive to the development of convection, especially the enhancement in the middle troposphere. In contrast, the convective storms develop rapidly in this test, as the most intensive one. The wind field variations have significant impacts on the structure and organization of the storm. The enhancement of wind field in the middle troposphere facilitates the intension of the middle-level rotation in convective storm, the reduction of the storm scale, and the organized evolution of convective storms. The strengthening of the wind field in the lower troposphere is conducive to the development of the low-level secondary circulation of the storm and the cyclonic vorticity at the middle and low levels on the inflowing side of the storms.
{"title":"STUDY ON SENSITIVITY OF WIND FIELD VARIATION TO STRUCTURE AND DEVELOPMENT OF CONVECTIVE STORMS","authors":"Wu Hai-ying, Zeng Ming-jian, Mei Haixia, Zhang Bing","doi":"10.16555/J.1006-8775.2020.006","DOIUrl":"https://doi.org/10.16555/J.1006-8775.2020.006","url":null,"abstract":"In order to study the impacts of wind field variations in the middle and lower troposphere on the development and structure of storms, we carried out numerical experiments on cases of severe convection in the Jianghuai area under the background of cold vortex on April 28, 2015. The results show that the structure and development of convective storms are highly sensitive to the changes of wind fields, and the adjustment of wind fields in the middle or lower troposphere will lead to significant changes in the development and structure of storms. When the wind field in the middle or lower troposphere is weakened, the development of convective storms attenuates to some extent compared with that in the control experiment, and the ways of attenuation in the two experiments are different. In the attenuation test of wind field at the middle level, convective storms obviously weaken at all stages in its development, while for the wind field at the low level, the convective storms weaken only in the initial stage of storm. On the contrary, the enhancement of the wind field in the middle or lower troposphere is conducive to the development of convection, especially the enhancement in the middle troposphere. In contrast, the convective storms develop rapidly in this test, as the most intensive one. The wind field variations have significant impacts on the structure and organization of the storm. The enhancement of wind field in the middle troposphere facilitates the intension of the middle-level rotation in convective storm, the reduction of the storm scale, and the organized evolution of convective storms. The strengthening of the wind field in the lower troposphere is conducive to the development of the low-level secondary circulation of the storm and the cyclonic vorticity at the middle and low levels on the inflowing side of the storms.","PeriodicalId":17432,"journal":{"name":"热带气象学报","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89011512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}