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Analysis on the Reason of Local Heavy Rainstorm forecast error in the Subtropical High Control

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Meteorological and Environmental Research 2011年第2期2卷 13-17页

作者： LV Xiao-hua DAI Jin WU Jin-hua LI Wen-ming Shaoyang Meteorological Bureau in Hunan Province Shaoyang 422000China Changde Meteorological Bureau in Hunan Changde 415000China

[Objective] The research aimed to study the reason of local heavy rainstorm forecast error in the subtropical high control. [Method] Started from summarizing the reason of forecast error, by using the conventional ground observation data, the upper air sounding data, T639, T213 and European Center (ECMWF) numerical prediction product data, GFS precipitation forecast product of U.S. National Center for Environmental Prediction, the weather situation, physical quantity field in a heavy rainstorm process which happened in the north of Shaoyang at night on August 5, 2010 were fully analyzed. Based on the numerical analysis forecast product data, the reason of heavy rainstorm forecast error in the subtropical high was comprehensively analyzed by using the comparison and analysis method of forecast and actual situation. [Result] The forecasters didn’t deeply and carefully analyze the weather situation. On the surface, 500 hPa was controlled by the subtropical high, but there was the weak shear line in 700 and 850 hPa. Moreover, they neglected the influences of weak cold air and easterlies wave. The subtropical high quickly weakened, and the system adjustment was too quick. The wind field variations in 850, 700 and 500 hPa which were forecasted by ECMWF had the big error with the actual situation. It was by east about 2 longitudes than the actual situation. In summer forecast, they only considered the intensity and position variations of 500 hPa subtropical high, and neglected the situation variations in the middle, low levels and on the ground. It was the most key element which caused the rainstorm forecast error in the subtropical high. The forecast error of numerical forecast products on the height field situation variation was big. The precipitation forecasts of Japan FSAS, U.S. National Center for Environmental Prediction GFS, T639 and T213 were all small. The humidity field forecast value of T639 was small. In the rainstorm forecast, the local rainstorm forecast inde

关键词： Heavy rainstorm Subtropical high forecast error Reason analysis China

How Do Deep Learning forecasting Models Perform for Surface Variables in the South China Sea Compared to Operational Oceanography forecasting Systems?

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Advances in Atmospheric Sciences 2025年第1期42卷 178-189页

作者： Ziqing ZU Jiangjiang XIA Xueming ZHU Marie DREVILLON Huier MO Xiao LOU Qian ZHOU Yunfei ZHANG Qing YANG Key Laboratory of Marine Hazards forecasting National Marine Environmental Forecasting CenterMinistry of Natural ResourcesBeijing 100081China Key Laboratory of Regional Climate-Environment for Temperate East Asia(RCE-TEA) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519000China Mercator Ocean International Ramonville Saint Agne 31400France

It is fundamental and useful to investigate how deep learning forecasting models(DLMs)perform compared to operational oceanography forecast systems(OFSs).However,few studies have intercompared their performances using an identical *** this study,three physically reasonable DLMs are implemented for the forecasting of the sea surface temperature(SST),sea level anomaly(SLA),and sea surface velocity in the South China *** DLMs are validated against both the testing dataset and the“OceanPredict”Class 4 *** show that the DLMs'RMSEs against the latter increase by 44%,245%,302%,and 109%for SST,SLA,current speed,and direction,respectively,compared to those against the ***,different references have significant influences on the validation,and it is necessary to use an identical and independent reference to intercompare the DLMs and *** the Class 4 dataset,the DLMs present significantly better performance for SLA than the OFSs,and slightly better performances for other *** error patterns of the DLMs and OFSs show a high degree of similarity,which is reasonable from the viewpoint of predictability,facilitating further applications of the *** extreme events,the DLMs and OFSs both present large but similar forecast errors for SLA and current speed,while the DLMs are likely to give larger errors for SST and current *** study provides an evaluation of the forecast skills of commonly used DLMs and provides an example to objectively intercompare different DLMs.

关键词： forecast error deep learning forecasting model operational oceanography forecasting system validation intercomparison

Large tropical cyclone track forecast errors of global numerical weather prediction models in western North Pacific basin

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Tropical Cyclone Research and Review 2021年第3期10卷 151-169页

作者： Chi Kit Tang Johnny C.L.Chan Munehiko Yamaguchi School of Energy and Environment City University of Hong KongHong KongChina Meteorological Research Institute Japan Meteorological AgencyJapan

Although tropical cyclone(TC)track forecast errors(TFEs)of operational warning centres have substantially decreased in recent decades,there are still many cases with large *** International Grand Global Ensemble(TIGGE)data are used to study the possible reasons for the large TFE cases and to compare the performance of different numerical weather prediction(NWP)***-four TCs in the western North Pacific during the period 2007-2014 with TFEs(+24 to+120 h)larger than the 75 th percentile of the annual error distribution(with a total of 93 cases)are *** categories of situations are found to be associated with large *** include the interaction of the outer structure of the TC with tropical weather systems,the intensity of the TC,the extension of the subtropical high(SH)and the interaction with the westerly *** crucial factor of each category attributed to the large TFE is *** the TIGGE model predictions,the models of the European Centre for Medium-Range Weather forecasts and the UK Met Office generally have a smaller *** performance of different models in different situations is discussed.

关键词： Consensus Numerical weather prediction forecast error Tropical cyclones Track prediction TIGGE WGNE

Uncertainties and error growth in forecasting the record-breaking rainfall in Zhengzhou,Henan on 19–20 July 2021

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Science China Earth Sciences 2022年第10期65卷 1903-1920页

作者： Yunji ZHANG Huizhen YU Murong ZHANG Yawen YANG Zhiyong MENG Department of Meteorology and Atmospheric Science Pennsylvania State UniversityUniversity ParkPennsylvania 16802USA Qingdao Meteorological Bureau Qingdao 266003China State Key Laboratory of Marine Environmental Science College of Ocean and Earth SciencesXiamen UniversityXiamen 361102China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China Department of Atmospheric and Oceanic Sciences School of PhysicsPeking UniversityBeijing 100871China

This study explores the controlling factors of the uncertainties and error growth at different spatial and temporal scales in forecasting the high-impact extremely heavy rainfall event that occurred in Zhengzhou,Henan Province China on 19−20 July 2021 with a record-breaking hourly rainfall exceeding 200 mm and a 24-h rainfall exceeding 600 *** show that the strengths of the mid-level low-pressure system,the upper-level divergence,and the low-level jet determine both the amount of the extreme 24-h accumulated and hourly rainfall at 0800 *** forecast uncertainties of the accumulated rainfall are insensitive to the magnitude and the spatial structure of the tiny,unobservable errors in the initial conditions of the ensemble forecasts generated with Global Ensemble forecast System(GEFS)or sub-grid-scale perturbations,suggesting that the predictability of this event is intrinsically *** dominance of upscale rather than upamplitude error growth is demonstrated under the regime of k^(−5/3) power spectra by revealing the inability of large-scale errors to grow until the amplitude of small-scale errors has increased to an adequate amplitude,and an apparent transfer of the fastest growing scale from smaller to larger scales with a slower growth rate at larger *** convective activities play a critical role in enhancing the overall error growth rate with a larger error growth rate at smaller *** addition,initial perturbations with different structures have different error growth features at larger scales in different variables in a regime transitioning from the k^(−5/3) to k^(−3) power *** growth with conditional nonlinear optimal perturbation(CNOP)tends to be more upamplitude relative to the GEFS or sub-grid-scale perturbations possibly owing to the inherited error growth feature of CNOP,the inability of convective parameterization scheme to rebuild the k^(−5/3) power spectra at the mesoscales,and different error growth characteristics in

关键词： Extremely heavy rainfall forecast error Predictability Ensemble forecast Henan

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Effect of Meteorological Data Assimilation on Regional Air Quality forecasts over the Korean Peninsula

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Journal of Meteorological Research 2024年第2期38卷 262-284页

作者： Yunjae CHO Hyun Mee KIM Eun-Gyeong YANG Yonghee LEE Jae-Bum LEE Soyoung HA Department of Atmospheric Sciences Yonsei UniversitySeoul 03722Republic of Korea Air Quality forecasting Center National Institute of Environmental ResearchIncheon 22689Republic of Korea National Center for Atmospheric Research BoulderCO 80305USA University of Maryland Baltimore County BaltimoreMD 21250USA Global Modeling and Assimilation Office NASA Goddard Space Flight CenterGreenbeltMD 20771USA

The Weather Research and forecasting model coupled with Chemistry(WRF-Chem),a type of online coupled chemistry-meteorology model(CCMM),considers the interaction between air quality and meteorology to improve air quality *** data assimilation(DA)can be used to reduce uncertainty in meteorological field,which is one factor causing prediction uncertainty in the *** this study,WRF-Chem and three-dimensional variational DA were used to examine the impact of meteorological DA on air quality and meteorological forecasts over the Korean *** nesting model domains were configured over East Asia(outer domain)and the Korean Peninsula(inner domain).Three experiments were conducted by using different DA domains to determine the optimal model domain for the meteorological *** the meteorological DA was performed in the outer domain or both the outer and inner domains,the root-mean-square error(RMSE),bias of the predicted particulate matter(PM)concentrations,and the RMSE of predicted meteorological variables against the observations were smaller than those in the experiment where the meteorological DA was performed only in the inner *** indicates that the improvement of the synoptic meteorological fields by DA in the outer domain enhanced the meteorological initial and boundary conditions for the inner domain,subsequently improving air quality and meteorological *** to the experiment without meteorological DA,the RMSE and bias of the meteorological and PM variables were smaller in the experiments with *** effect of meteorological DA on the improvement of PM predictions lasted for approximately 58-66 h,depending on the ***,the uncertainty reduction in the meteorological initial condition by the meteorological DA contributed to a reduction of the forecast errors of both meteorology and air quality.

关键词： meteorological data assimilation regional air quality forecast particulate matter concentration optimal model domain forecast error WRF-Chem

Managerial Ability and forecast Accuracy

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Journal of Modern Accounting and Auditing 2017年第12期13卷 508-520页

作者： Panagiotis I. Chronopoulos Georgia Siougle Athens University of Economics and Business Greece

We examine the relation between managerial ability and management forecast accuracy. We base our analysis on S＆P 500 Composite Index constituents for the period of 2006-2012. Data were collected from Thomson Reuteurs, Compustat and Demerjian, Lev, and McVay （2012）. We find that forecast accuracy is positively associated with managerial ability in the case of sales forecasts. Specifically, more able managers are associated with lower magnitude＇s forecast errors in the case of sales forecasts. Additional analysis finds that managerial ability is immaterial to EPS figures＇ forecast accuracy, i.e., EPS forecasts appear not to be affected by manager＇s superiority. Regarding sales forecasts, the results are consistent with the assertion that managers impact the quality of the delivered management forecasts. Regarding EPS forecasts, the results are in alignment with Demerjian, Lev, Lewis, and McVay （2013） who highlighted that managerial ability is an ability score related to the entire management team.

关键词： managerial ability forecast accuracy forecast error

A review of recent advances(2018–2021)on tropical cyclone intensity change from operational perspectives,part 2:forecasts by operational centers

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Tropical Cyclone Research and Review 2023年第1期12卷 50-63页

作者： Weiguo Wang Zhan Zhang John P.Cangialosi Michael Brennan Levi Cowan Peter Clegg Hosomi Takuya Ikegami Masaaki Ananda Kumar Das Mrutyunjay Mohapatra Monica Sharma John A.Knaff John Kaplan Thomas Birchard James D.Doyle Julian Heming Jonathan Moskaitis Suhong Ma Charles Sampson Liguang Wu Eric Blake NOAA/NWS/NCEP Environmental Modeling Center USA NOAA/NWS/NCEP National Hurricane Center USA Joint Typhoon Warning Center USA Bureau of Meteorology Australia Japan Meteorological Agency Japan Indian Meteorological Department India NOAA Center for Satellite Applications and Research USA NOAA/AOML Hurricane Research Division USA Central Pacific Hurricane Center USA Naval Research Laboratory USA Met Office UK China Meteorological Administration China Fudan University ShanghaiChina IMSG@NOAA/NWS/OSTI USA

This paper summarizes the progress and activities of tropical cyclone(TC)operational forecast centers during the last four years(2018–2021).It is part II of the review on TC intensity change from the operational perspective in the rapporteur report presented to the 10th International Workshop on TCs(IWTC)held in Bali,Indonesia,from Dec.5–9,*** I of the review has focused on the progress of dynamical model forecast *** part discusses the performance of TC intensity and rapid intensification forecasts from several operational *** is shown that the TC intensity forecast errors have continued to decrease since the 9th IWTC held in *** particular,the improvement of rapid intensification forecasts has accelerated,compared with years before *** models,operational procedures,tools and techniques,as well as recent challenging cases from 2018 to 2021 identified by operational forecast centers are *** needs and recommendations are also discussed.©2023 The Shanghai Typhoon Institute of China Meteorological *** services by Elsevier *** behalf of KeAi Communication *** is an open access article under the CC BY-NC-ND license(http://***/licenses/by-nc-nd/4.0/).

关键词： forecast error Intensity forecast Operational forecasts Tropical cyclone

Accounting standard changes and foreign analyst behavior:Evidence from China

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China Journal of Accounting Research 2012年第1期5卷 27-43页

作者： Yutao Wang Yu Hou Xiaolin Chen School of Accountancy Central University of Finance and Economics Rotman School of Management University of Toronto School of Accounting Jiujiang University

This study investigates changes in foreign analyst behavior before and after Chinese New Accounting Standards was implemented during *** empirical results show that after the new accounting standards were implemented,forecast error among foreign analysts decreased in both absolute and relative terms in comparison with domestic analysts,and foreign analysts forecast earnings more frequently than they did before the new accounting *** results imply that the implementation of new accounting standards in the Chinese capital market helped mitigate both information asymmetry between listed firms in China and foreign investors,and the "home bias" of foreign *** also increased the attractiveness of listed firms and facilitated international communication and *** study also has significant implications for how resource allocation efficiency in the Chinese capital market can be raised and how the "introducing in" policy should be assessed.

关键词： New accounting standards Analyst forecasts forecast error