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Progress of MJO prediction at CMA from Phase I to Phase II of the Sub-Seasonal to Seasonal prediction Project

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Advances in Atmospheric Sciences 2023年第10期40卷 1799-1815页

作者： Junchen YAO Xiangwen LIU Tongwen WU Jinghui YAN Qiaoping LI Weihua JIE Center for earth system modeling and prediction of China Meteorological Administration Beijing 100081China

As one of the participants in the Subseasonal to Seasonal(S2S)prediction Project,the China Meteorological Administration(CMA)has adopted several model versions to participate in the S2S *** study evaluates the models’capability to simulate and predict the Madden-Julian Oscillation(MJO).Three versions of the Beijing Climate Center Climate system Model(BCC-CSM)are used to conduct historical simulations and re-forecast experiments(referred to as EXP1,EXP1-M,and EXP2,respectively).In simulating MJO characteristics,the newly-developed high-resolution BCC-CSM outperforms its *** terms of MJO prediction,the useful prediction skill of the MJO index is enhanced from 15 days in EXP1 to 22 days in EXP1-M,and further to 24 days in *** the first forecast week,the better initial condition in EXP2 largely contributes to the enhancement of MJO prediction ***,during forecast weeks 2–3,EXP2 shows little advantage compared with EXP1-M because the increased skill at MJO initial phases 6–7 is largely offset by the degraded skill at MJO initial phases 2–*** at initial phases 2–3,EXP1-M skillfully captures the wind field and Kelvin-wave response to MJO convection,leading to the highest prediction skill of the *** results reveal that,during the participation of the CMA models in the S2S Project,both the improved model initialization and updated model physics played positive roles in improving MJO *** efforts should focus on improving the model physics to better simulate MJO convection over the Maritime Continent and further improve MJO prediction at long lead times.

关键词： Madden-Julian Oscillation(MJO) Subseasonal to Seasonal(S2S) prediction skill improvement initial phase

Pre-Processing,Quality Assurance,and Use of Global Atmospheric Motion Vector Observations in CRA

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Journal of Meteorological Research 2022年第6期36卷 947-962页

作者： Minyan WANG Shuang YAO Lipeng JIANG Tao ZHANG Chunxiang SHI Ting ZHU National Meteorological Information centre China Meteorological AdministrationBeijing 100081 CMA earth system modeling and prediction centre China Meteorological Administration(CMA)Beijing 100081

Assimilation of atmospheric motion vectors(AMVs)is important in the initialization of the atmospheric state in numerical weather prediction models,especially over oceans and at high latitudes where conventional data are *** paper presents a detailed description of the pre-processing,quality assurance,and use of global AMVs in China’s first generation of the 40-yr(1979-2018)CRA global atmospheric reanalysis product.A new AMV archive is integrated from near real-time operational Global Telecommunication system data and reprocessed AMV datasets released or produced mainly during 2014-2016 according to a priority *** avoid the misuse of data with systematic quality problems,the observations of all 18 types of AMVs from 54 satellites are pre-evaluated over the whole time *** pre-evaluation system developed by the CRA team is based on the NCEP Gridpoint Statistical Interpolation(GSI)three-dimensional variational assimilation system and the ERA-Interim reanalysis *** AMVs in the new AMV archive are denser than the AMVs prepared for the Climate Forecast system Reanalysis product,the bias and root-mean-square values are smaller,and the time series are *** new AMV archive is assimilated in the CRA product based on the NCEP GSI assimilation procedure and quality control configuration with reference to the pre-evaluation *** is the first time that the reprocessed AMVs from Fengyun-2 satellites from June 2005 to July 2017 are assimilated in a reanalysis *** assimilation features inspire confidence in the accuracy and stability of these *** mean root-mean-square values of the observation minus analysis infrared,water vapor,and visible AMV were 1.5-3.4,2.7-3.6,and 1.3-2.1 m s-1,*** experience of integrating,pre-evaluating,and assimilating AMV observations is valuable for the next generation of reanalysis products.

关键词： reanalysis CRA(China’s first generation of 40-yr global atmospheric ReAnalysis product) atmospheric motion vector integration assimilation reprocessed data

Blacklist Design of AMDAR Temperature Data and Their Application in the CMA-GFS

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Journal of Tropical Meteorology 2021年第4期27卷 368-377页

作者： WANG Rui-wen HAN Wei TIAN Wei-hong GONG Jian-dong CMA earth system modeling and prediction centre Beijing 100081 China State Key Laboratory of Severe Weather Beijing 100081 China

Blacklist methods are used in the CMA Global Forecasting system(CMA-GFS)to improve the application of aircraft temperature data to numerical weather prediction in the Northern Hemisphere and the *** this paper,the ERA5 re-analysis data are used to analyze aircraft temperature observation errors of each aircraft and a blacklist is established using pre-quality controls and threshold *** blacklist-filtered and blacklisted aircraft temperature data are then applied to the four-dimensional variational assimilation system,respectively,and an assimilation cycle forecast for the period from September 1 to 30,2019 is carried *** results show an uneven distribution in the global aircraft blacklist *** the application of the blacklist methods,the RMSE of geopotential height and temperature analysis field decrease in the vertical direction by a maximum of~1.5 gpm at 200 hPa and~0.15 K at 250 hPa,***,the blacklist methods of aircraft temperature data improve the analysis and forecast in the CMA-GFS.

关键词： CMA-GFS blacklist AMDAR four-dimensional variational assimilation

Improved Microwave Ocean Emissivity and Reflectivity Models Derived from Two-Scale Roughness Theory

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Advances in Atmospheric Sciences 2023年第10期40卷 1923-1938页

作者： Lingli HE Fuzhong WENG Chinese Academy of Meteorological Sciences Beijing 100081China University of Chinese Academy of Sciences Beijing 100049China CMA earth system modeling and prediction centre Beijing 100081China

The Geometrical Optics(GO)approach and the FAST Emissivity Model(FASTEM)are widely used to estimate the surface radiative components in atmospheric radiative transfer simulations,but their applications are limited in specific *** this study,a two-scale reflectivity model(TSRM)and a two-scale emissivity model(TSEM)are developed from the two-scale roughness *** GO which only computes six non-zero elements in the reflectivity matrix,The TSRM includes 16 elements of Stokes reflectivity matrix which are important for improving radiative transfer simulation accuracy in a scattering *** covers the frequency range from L-to *** dependences of all TSRM elements on zenith angle,wind speed,and frequency are derived and analyzed in *** a set of downwelling radiances in microwave frequencies,the reflected upwelling brightness temperature(BTs)are calculated from both TSRM and GO and compared for analyzing their *** TSRM not only includes the effects of GO but also accounts for the small-scale Bragg scattering effect in an order of several degrees in Kelvins in brightness ***,the third and fourth components of the Stokes vector can only be produced from the *** the emitted radiation,BT differences in vertical polarization between a TSEM and FASTEM are generally less than 5 K when the satellite zenith angle is less than 40°,whereas those for the horizontal component can be quite significant,greater than 20 K.

关键词： emissivity microwave remote sensing reflectivity matrix two-scale roughness theory

Implementation of CMA-GFS 3D-Var system on the Yin-Yang Grid

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Journal of Tropical Meteorology 2021年第4期27卷 346-354页

作者： ZHUANG Zhao-rong XUE Ji-shan SHEN Xue-shun LI Xing-liang CMA earth system modeling and prediction centre Beijing 100081 China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081 China

The global three-dimensional variational(3D-Var)data assimilation is implemented on a new quasi-uniform overset(Yin-Yang)grid on *** a quasi-uniform spherical grid,it covers the sphere by overlapping two perpendicularly oriented grid components which is nothing but low latitude region of the usual latitude-longitude *** on this characteristic of the Yin-Yang grid,it enables us to implement the regional 3D-Var system efficiently and accurately on the Yin or Yang component grid,*** global analysis could update directly from the regional analysis since they have the same configurations like the precondition of eigenvalue decomposition for vertical direction,recursive filtering for horizontal direction,minimization method and observation operator and so ***,the balance equation and vector wind are needed to be paid more attention on the Yin grid analysis due to its coordinate *** to spread the observation information near the boundary of Yin and Yang grid is a key to the 3D-Var *** double the horizontal correlation length distance in the overset boundary of Yin and Yang grid has successfully solved the *** results show that the analysis on the Yin-Yang grid is reasonable and similar to the result on the latitude-longitude(LAT-LON)*** paper provides a promising strategy for the development of a 3D-Var global system for overset grids.

关键词： Yin-Yang grid latitude-longitude grid CMA-GFS regional 3D-Var global 3D-Var

Classification analysis of prediction skill among ensemble members in MJO subseasonal predictions——based on the results of the CAMS-CSM subseasonal prediction system

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Atmospheric and Oceanic Science Letters 2024年第4期17卷 8-14页

作者： Yihao Peng Xiaolei Liu Jingzhi Su Xinli Liu State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijingChina Center for earth system modeling and prediction of CMA(CEMC) BeijingChina Key Laboratory of earth system modeling and prediction China Meteorological Administration BeijingChina

由于模式误差和初始误差所致,次季节-季节预报技巧整体偏低.国际上多数模式都采用集合预报的方式来提高次季节预报的准确率.热带大气季节内振荡(MJO)作为次季节尺度可预报性的重要来源,其预测水平取决于模式性能和MJO事件本身的物理特性... 详细信息

由于模式误差和初始误差所致,次季节-季节预报技巧整体偏低.国际上多数模式都采用集合预报的方式来提高次季节预报的准确率.热带大气季节内振荡(MJO)作为次季节尺度可预报性的重要来源,其预测水平取决于模式性能和MJO事件本身的物理特性.根据中国气象科学研究院气候系统模式次季节预测系统的回报结果,结合不同类型MJO事件的特征,对模式集合成员间的预报技巧进行了分类和比较.在集合成员预报技巧普遍较高的一类MJO事件中,对流异常信号持续时间较长,强度较大,强对流异常中心主要位于印度洋区域,并逐渐东传至西太平洋.在集合成员预报技巧多数较差的MJO事件中,对流异常信号的强度最弱,维持时间最短.在集合成员预报技巧优劣参半的类别中,MJO往往持续时间较短,强度较低,在后续传播过程中,对流异常中心多停驻在海洋性大陆区域.

关键词：次季节-季节预测预报技巧热带大气季节内振荡

Comparison of tropical cyclone thermal structures derived from ATMS and synthetic AMSU-A/MHS

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Atmospheric and Oceanic Science Letters 2024年第4期17卷 29-34页

作者： Wenyu Li Fuzhong Weng Chinese Academy of Meteorological Sciences BeijingChina Center for earth system modeling and prediction of CMA BeijingChina

热带气旋(TC)的暖心反映了其强度和变化.微波探测数据被广泛用于探测TC暖心,但观测到的TC暖心强度可能因仪器而异.本研究利用先进技术微波探测仪(ATMS)的过采样数据重采样至与先进微波探测仪(AMSU-A)一致的亮温,称为类AMSU数据.通过对... 详细信息

热带气旋(TC)的暖心反映了其强度和变化.微波探测数据被广泛用于探测TC暖心,但观测到的TC暖心强度可能因仪器而异.本研究利用先进技术微波探测仪(ATMS)的过采样数据重采样至与先进微波探测仪(AMSU-A)一致的亮温,称为类AMSU数据.通过对比发现,ATMS的观测更加细致,较好地刻画了TC眼区和云带.使用ATMS和类-AMSU数据反演多个TC的暖心发现,在250 hPa,使用ATMS数据反演的暖心强度比类-AMSU高约1-2K,并且其暖心结构更详细.

关键词：热带气旋暖心 ATMS AMSU-A 微波探测数据

New Version of the CMA-GFS Dynamical Core Based on the Predictor–Corrector Time Integration Scheme

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Journal of Meteorological Research 2023年第3期37卷 273-285页

作者： Xueshun SHEN Yong SU Hongliang ZHANG Jianglin HU CMA earth system modeling and prediction centre China Meteorological Administration(CMA)Beijing 100081 State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081

The operational numerical weather prediction system established by the China Meteorological Administration(CMA),based on the Global/Regional Assimilation and prediction system(GRAPES)model,adopts the classical semi-implicit semi-Lagrangian(SISL)time integration *** paper describes a major upgrade to the dynamical core of the CMA global forecast system(CMA-GFS),which was successfully incorporated into operation in *** the upgrade,the classical SISL is further developed into a predictor–corrector scheme,a three-dimensional(3D)reference profile instead of the original isothermal reference profile is applied when implementing the semi-implicit algorithm,and a hybrid terrain-following vertical coordinate system is also *** new version of the dynamical core greatly improves the model performance,the time integration reaches second-order accuracy,the time step can be extended by 50%,and the efficiency is greatly improved(by approximately 30%).Atmospheric circulation simulation is systematically improved,and deviations in temperature,wind,and humidity are *** new version of the dynamical core provides a solid foundation for further development of the entire operational system of the CMA.

关键词： Global/Regional Assimilation and prediction system(GRAPES) China Meteorological Administration global forecast system(CMA-GFS) predictor-corrector three-dimensional(3D)reference profile

Stochastically Perturbed Parameterizations for the Process-Level Representation of Model Uncertainties in the CMA Global Ensemble prediction system

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Journal of Meteorological Research 2022年第5期36卷 733-749页

作者： Fei PENG Xiaoli LI Jing CHEN CMA earth system modeling and prediction centre China Meteorological Administration(CMA)Beijing 100081 State Key Laboratory of Severe Weather China Meteorological AdministrationBeijing 100081 National Meteorological centre China Meteorological AdministrationBeijing 100081

To represent model uncertainties at the physical process level in the China Meteorological Administration global ensemble prediction system(CMA-GEPS),a stochastically perturbed parameterization(SPP)scheme is developed by perturbing 16 parameters or variables selected from three physical parameterization schemes for the planetary boundary layer,cumulus convection,and cloud *** chosen quantity is perturbed independently with temporally and spatially correlated perturbations sampled from log-normal *** of the SPP scheme on CMA-GEPS are investigated comprehensively by using the stochastically perturbed parametrization tendencies(SPPT)scheme as a *** the absence of initial-condition perturbations,perturbation structures introduced by the two schemes are investigated by analyzing the ensemble spread of three forecast variables’physical tendencies and perturbation energy in ensembles generated by the separate use of SPP and *** is revealed that both schemes yield different perturbation structures and can simulate different sources of model *** initialcondition perturbations are activated,the influences of the two schemes on the performance of CMA-GEPS are assessed by calculating verification scores for both upper-air and surface *** improvements in ensemble reliability and probabilistic skill introduced by SPP and SPPT are mainly located in the ***,the vast majority of the reliability improvements(including increases in ensemble spread and reductions in outliers)are statistically significant,and a smaller proportion of the improvements in probabilistic skill(i.e.,decreases in continuously ranked probability score)reach statistical *** with SPPT,SPP generally has more beneficial impacts on200-hPa and 2-m temperature,along with 925-hPa and 2-m specific humidity,during the whole 15-day forecast *** other examined variables,such as 850-hPa zonal wind,850-hPa temperature,and

关键词： model uncertainty global ensemble forecast stochastic physics parameter perturbation perturbation structure