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Ensemble Based Diagnosis of the Track Errors of Super Typhoon Mangkhut(2018)

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Journal of Meteorological Research 2020年第2期34卷 353-367页

作者： Ling HUANG qilin wan Chunxia LIU Huijun HUANG Institute of Tropical and Marine Meteorology of China Meteorological Administration Guangzhou 510000

Super Typhoon Mangkhut(2018)was the most high-impact typhoon in 2018 because of its long lifespan and significant *** operational track forecasts in the short-to-medium range(deterministic and probabilistic forecast)showed a great uncertainty and the forecast landing points varied with different lead *** study applied ensembles of high-resolution ECMWF forecasts to investigate the major factors and mechanisms of the bias production of the Mangkhut forecast *** ensembles with the largest track bias were analyzed to examine the possible bias associated *** results suggested that environmental steering flows were the main cause for the erroneous southward track error with a variance contribution of 72%.The tropical cyclone(TC)size difference and the interaction of the TC with the subtropical high(SH)were other two key factors that contributed to the track ***,larger TCs may have led to a stronger erosion of the southern part of the SH,and thus induced significant changes in the large-scale environment and eventually resulted in an additional northward movement of TC.

关键词： Super Typhoon Mangkhut ECMWF ensemble tropical cyclone track

An Initialization Scheme for Weak Tropical Cyclones in the South China Sea

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Journal of Meteorological Research 2021年第2期35卷 358-370页

作者： Jihang LI qilin wan Daosheng XU Yanyan HUANG Xubin ZHANG Guangzhou Institute of Tropical and Marine Meteorology China Meteorological AdministrationGuangzhou 510640

Variations in the initial structure of tropical cyclones(TCs) inevitably affect prediction results;however, the bogus model cannot accurately describe the structure of a weak tropical cyclone with increased initial field resolution. This study aims to construct a model to improve the prediction of weak TC in southern China. Based on the ECMWF 0.1° analysis data, several vortices were filtered out from tropical depressions and tropical storms in 2018 and 2019 to represent a weak TC reservoir in the South China Sea. For different simulation objects, filtered vortices were combined with the TC environmental field to form ensemble members. The observed TC information was assimilated for simulating TCs Bebinca, Mun, and Ewiniar to verify the feasibility of the proposed model, based on the Global/Regional Assimilation and Prediction Enhanced System(GRAPES) 9-km model developed by the Guangzhou Institute of Tropical and Marine Meteorology. The results show that the initialization scheme of the weak tropical cyclone model improved the intensity prediction of the TC by 26.81%(Bebinca), 18.65%(Mun), and 47.00%(Ewiniar), compared with the control experiment. Because typhoon intensity forecasting has not notably improved for many years, this scheme has certain scientific and operational significance.

关键词： tropical cyclones(TCs) intensity forecast initialization scheme for weak TC

Effect of Aerosol Particles on Orographic Clouds:Sensitivity to Autoconversion Schemes

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Advances in Atmospheric Sciences 2020年第2期37卷 229-238页

作者： Hui XIAO Yan YIN Pengguo ZHAO qilin wan Xiantong LIU Guangzhou Institute of Tropical and Marine Meteorology China Meteorological AdministrationGuangzhou 510641China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China College of Atmospheric Science Chengdu University of Information&TechnologyChengdu 610225China

Aerosol particles can serve as cloud condensation nuclei(CCN)to influence orographic ***,which describes the initial formation of raindrops from the collision of cloud droplets,is an important process for aerosol-cloud-precipitation *** this study,seven autoconversion schemes are used to investigate the impact of CCN on orographic warm-phase *** the initial cloud droplet concentration is increased from 100 cm^(-3)to 1000 cm^(-3)(to represent an increase in CCN),the cloud water increases and then the rainwater is suppressed due to a decrease in the autoconversion rate,leading to a spatial shift in surface *** of the results from the autoconversion schemes show that the sensitivity of cloud water,rainwater,and surface precipitation to a change in the concentration of CCN is different from scheme to *** particular,the decrease in orographic precipitation due to increasing CCN is found to range from-87%to-10%depending on the autoconversion ***,the surface precipitation distribution also changes significantly by scheme or CCN concentration,and the increase in the spillover(ratio of precipitation on the leeward side to total precipitation)induced by increased CCN ranges from 10%to 55%under different autoconversion *** simulations suggest that autoconversion parameterization schemes should not be ignored in the interaction of aerosol and orographic cloud.

关键词： orographic cloud precipitation autoconversion aerosol particles

The Simulation of Five Tropical Cyclones by Sample Optimization of Ensemble Forecasting Based on the Observed Track and Intensity

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Advances in Atmospheric Sciences 2021年第10期38卷 1763-1777页

作者： Jihang LI Zhiyan ZHANG Lu LIU Xubin ZHANG Jingxuan QU and qilin wan Guangzhou Institute of Tropical and Marine Meteorology Guangzhou 510640China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China

The quality of ensemble forecasting is seriously affected by sample *** this study,the distributions of ensemble members based on the observed track and intensity of tropical cyclones(TCs)were optimized and their influence on the simulation results was *** and observed tracks and intensities of TCs were compared and these two indicators were combined and weighted to score the *** with higher scores were retained and samples with lower scores were eliminated to improve the overall quality of the ensemble *** each sample,the track score and intensity score were added as the final score of the sample with weight proportions of 10 to 0,9 to 1,8 to 2,7 to 3,6 to 4,5 to *** were named as“tr”,“91”,“82”,“73”,“64”,and“55”,*** WRF model was used to simulate five tropical cyclones in the northwestern Pacific to test the ability of this scheme to improve the forecast track and intensity of these *** results show that the sample optimization effectively reduced the track and intensity error,“55”usually had better performance on the short-term intensity prediction,and“tr”had better performance in short-term track *** the overall performance of the track and intensity simulation,“91”was the best and most stable among all sample optimization *** results may provide some guidance for optimizing operational ensemble forecasting of TCs.

关键词： tropical cyclones ensemble forecast sample optimization observed track and intensity

Improvement of the Surface Pressure Operator in GRAPES and Its Application in Precipitation Forecasting in South China

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Advances in Atmospheric Sciences 2013年第2期30卷 354-366页

作者： HUANG Yanyan XUE Jishan wan qilin CHEN Zitong DING Weiyu ZHANG Chengzhong Guangzhou Institute of Tropical and Marine Meteorology Guangzhou 510080 ~tate Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081

In this study we investigated the problems involved in assimilating surface pressure in the current global and regional assimilation and prediction system, GRAPES. A new scheme of assimilating surface pressure was proposed, including a new interpolation scheme and a refreshed background covariance. The new scheme takes account of the differences between station elevation and model topography, and it especially deals with stations located at elevations below that of the first model level. Contrast experiments were conducted using both the original and the new assimilation schemes. The influence of the new interpolation scheme and the updated background covariance were investigated. Our results show that the new interpolation scheme utilized more observations and improved the quality of the mass analysis. The background covariance was refreshed using statistics resulting from the technique proposed by Parrish and Derber in 1992. Experiments show that the updated vertical covariance may have a positive influence on the analysis at higher levels of the atmosphere when assimilating surface pressure. This influence may be more significant if the quality of the background field at high levels is poor. A series of assimilation experiments were performed to test the validity of the new scheme. The corresponding simulation experiments were conducted using the analysis of both schemes as initial conditions. The results indicated that the new scheme leads to better forecasting of sea level pressure and precipitation in South China, especially the forecast of moderate and heavv rain.

关键词： GRAPES system surface pressure assimilation background covariance numerical simulation

Raindrop Size Distribution Parameters Retrieved from Guangzhou S-band Polarimetric Radar Observations

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Journal of Meteorological Research 2018年第4期32卷 571-583页

作者： Xiantong LIU qilin wan Hong wanG Hui XIAO Yu ZHANG Tengfei ZHENG Lu FENG Institute of Tropical and Marine Meteorology of China Meteorological Administration Guangzhou 510640 Guangzhou Meteorological Observatory Guangzhou 511430

According to the statistical shape-slope （μ-A） relationship observed for the first time by several 2D-Video-Distro-meters （2DVD） in southern China, a constrained gamma （C-G） model was proposed for the retrieval of rain drop size distributions （DSDs） from Guangzhou S-band polarimetric radar observations. Two typical precipitation processes were selected to verify the accuracy of the retrieval scheme. The p-A relationship： A = 0.0241μ^2 ＋ 0.867μ ＋ 2.453 was obtained based on the 2DVD observation results from at Huizhou Longmen station, which is a very representat-ive location in the area. Relying on the Guangzhou polarimetric radar measurements of radar reflectivity （ZHH） and differential reflectivity （ZDR）, the gamma （F） size distribution parameters （No, μ, and A） can be retrieved by the C-G model retrieval scheme. The results show that the Guangzhou polarimetric radar retrievals of DSDs were close to the 2DVD observations at Guangzhou Maofengshan station. The rain rate, mass mean diameter, and normalized inter-cept parameter of radar retrievals were in good agreement with the 2DVD observations, and the relative errors were less than 10%. The overall accuracy of the retrieval scheme was high. The retrieval scheme has established the rela-tionship between the polarimetric radar measurements and gamma size distribution parameters. It will be helpful to in-depth research and application of the dual-polarization radar data in microphysical precipitation processes analysis, as well as convection-resolved numerical model data assimilation and prediction effect evaluation.

关键词： Guangzhou S-band polarimetric radar 2D-Video-Disdrometer raindrop size distribution retrieval microphysics

Multi-scale Incremental Analysis Update Scheme and Its Application to Typhoon Mangkhut(2018)Prediction

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Advances in Atmospheric Sciences 2023年第1期40卷 95-109页

作者： Yan GAO Jiali FENG Xin XIA Jian SUN Yulong MA Dongmei CHEN qilin wan Guangdong-Hong Kong-Macao Greater Bay Area Weather Research Center for Monitoring Warning and Forecasting Shenzhen 518038China CMA Earth System Modeling and Prediction Centre China Meteorological AdministrationBeijing 100081China

In the traditional incremental analysis update(IAU)process,all analysis increments are treated as constant forcing in a model’s prognostic equations over a certain time *** approach effectively reduces high-frequency oscillations introduced by data ***,as different scales of increments have unique evolutionary speeds and life histories in a numerical model,the traditional IAU scheme cannot fully meet the requirements of short-term forecasting for the damping of high-frequency noise and may even cause systematic ***,a multi-scale IAU scheme is proposed in this *** increments were divided into different scale parts using a spatial filtering *** each scale increment,the optimal relaxation time in the IAU scheme was determined by the skill of the forecasting ***,different scales of analysis increments were added to the model integration during their optimal relaxation *** multi-scale IAU scheme can effectively reduce the noise and further improve the balance between large-scale and small-scale increments in the model initialization *** evaluate its performance,several numerical experiments were conducted to simulate the path and intensity of Typhoon Mangkhut(2018)and showed that:(1)the multi-scale IAU scheme had an obvious effect on noise control at the initial stage of data assimilation;(2)the optimal relaxation time for large-scale and small-scale increments was estimated as 6 h and 3 h,respectively;(3)the forecast performance of the multi-scale IAU scheme in the prediction of Typhoon Mangkhut(2018)was better than that of the traditional IAU *** results demonstrate the superiority of the multi-scale IAU scheme.

关键词： multi-scale incremental analysis updates optimal relaxation time 2-D discrete cosine transform GRAPES_Meso Typhoon Mangkhut(2018)

Comparative evaluation of the impact of GRAPES and MM5 meteorology on CMAQ prediction over Pearl River Delta, China

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Particuology 2018年第5期16卷 88-97页

作者： Tao Deng Yiang Chen qilin wan Yanxia Zhang Xuejiao Deng Yanyan Huang Guangfeng Dai Fei Li Institute of Tropical and Marine Meteorology/Guangdong Provincial Key Laboratory of Regional Numerical Weather Prediction China Meteorological AdministrationGuangzhou 510080China Key Laboratory of Meteorological Disaster Ministry of EducationJoint International Research Laboratory of Climate and Environment ChangeCollaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersKey Laboratory for Aerosol-Cloud-Precipitation of China Meteorological AdministrationNanjing University olin formation Science &TechnologyNanjing210044China

The community multiscale air quality (CMAQ) model was used to forecast air quality over the Pearl River Delta region from December 2013 to January *** pollution forecasting performance of CMAQ coupled with two different meteorological models,i.e.,the global/regional assimilation and prediction system (GRAPES) and the fifth-generation mesoscale model (MM5),was assessed by comparison with observational *** effects of meteorological factors and physicochemical processes on the forecast results were discussed through process *** results showed that both models exhibited good performance but that of GRAPES-CMAQ was *** was superior in predicting the overall variation tendencies of meteorological fields,but it showed large deviations in atmospheric pressure and wind *** contributed to the higher correlation coefficients of the pollutants with GRAPES-CMAQ but with greater *** underestimations of nitrate and ammonium salt contributed to the underestimations of both particulate matter and extinction *** emissions made the only positive contributions to surface layer SO2,CO,and *** was found that O3 originated primarily from horizontal and vertical transport and that its consumption was predominantly via chemical ***,NO2 was found derived primarily from chemical production.

关键词： Air quality Numerical simulation Global/regional assimilation and prediction system (GRAPES) Community multiscale air quality (CMAQ) Process analysis

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综合观测试验中的激光测风雷达探测性能分析

大气与环境光学学报 2024年第5期19卷 529-542页

作者：郑腾飞李肖雅万齐林于鑫杨晓雁于明洋陈炜杰蔡康龙佛山市气象局中国气象科学研究院灾害天气国家重点实验室广东佛山528000 青岛华航环境科技有限责任公司山东青岛266000 粤港澳大湾区气象监测预警预报中心深圳518000 广东省气象台广东广州510080 中山市气象局广东中山528400 汕头市气象局广东汕头515000

基于2019年6、7月广州超大城市综合观测试验中的地面资料,激光测风雷达、风廓线雷达资料以及广州S波段双偏振雷达资料,对WindPrint S4000型激光测风雷达和风廓线雷达进行观测对比,并尝试在不同降水强度条件下对激光测风雷达的探测性能... 详细信息

基于2019年6、7月广州超大城市综合观测试验中的地面资料,激光测风雷达、风廓线雷达资料以及广州S波段双偏振雷达资料,对WindPrint S4000型激光测风雷达和风廓线雷达进行观测对比,并尝试在不同降水强度条件下对激光测风雷达的探测性能进行综合评估分析。结果表明:激光测风雷达与风廓线雷达在非降水时段和非强降水时段观测性能一致性较好,能很好地捕捉到天气系统过境期间边界层低空风场的变化特征,但相比较而言,激光测风雷达成本更低,更加便捷高效,选址选点较为容易,更加符合大城市观测加密布网的需求;激光雷达的探测高度与降水量和降水强度均相关,但与降水强度关系更加密切,即当降水强度增加时,激光雷达的探测高度总体呈下降趋势,且当发生S波段双偏振天气雷达反射率因子达到50 dbz以上强度的降水时,激光测风雷达与风廓线雷达一样无法进行常规观测。

关键词：激光测风雷达风廓线雷达探测性能

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