Vol.26, NO.4, 2015

Display Method:
Sensitivity Analysis of Short-duration Heavy Rainfall Related Diagnostic Parameters with Point-area Verification
Tian Fuyou, Zheng Yongguang, Zhang Tao, Mao Dongyan, Tang Wenyuan, Zhou Qingliang, Sun Jianhua, Zhao Sixiong
2015, 26(4): 385-396. DOI: 10.11898/1001-7313.20150401
Abstract:
The knowledge about the short-duration heavy rainfall related diagnostic parameters is very important for improving the accuracy, and it can help understand the possible mechanism of meso-scale system producing short-duration heavy rainfall. The data collections of basic datum stations (verification stations), automatic meteorological observation stations (AMOSs), and 6-hours NCEP final analysis data (FNL) diagnostic parameters from 2011 to 2012 during 1 June and 31 August are used. By considering characteristics of rain gauge distribution, the total precipitable water and the best lifted index obtained from NCEP FNL are firstly analyzed with the "point-area" verification method to reveal the sensitivities of short-duration heavy rainfall to the environment conditions. Values of diagnostic parameters for a specific basic datum stations (verification stations) is obtained by adopting bilinear interpolation method.Results show that the popularly used verification is just special cases of "point-area" verification: One could be reached by setting infinitesimal searching radius, the other can be reached by setting the record threshold infinite. Both the total precipitable water and best lifted index have optimum thresholds indicating short-duration heavy rainfall, and the short-duration heavy rainfall in 3 hours can only be directly affected by the moisture and instability within the radius of 140 km. A searching radius and a record threshold of 140 km and 2 are supposed, respectively, for 1°×1° NCEP dataset. A total precipitable water of 55 mm divides the threat score (T) into monotone increasing and monotone decreasing parts, indicating under-forecast and over-forecast, respectively. A best lifted index of -2 ℃ divides the threat score into over-forecast and under-forecast parts. It is found that the total precipitable water and K index are equal better while both got the same highest threat scores of 0.275 with the bias (B) desirable and the false alarm ratio (F) and the hit rate (H) in the reasonable range. Short-duration heavy rainfall is most sensitive to parameters concerning the environment water vapor, nine of the top ten diagnostic parameters are water vapor related parameters. Parameters indicating environment instability conditions are also influencing, but parameters used to represent dynamic conditions and vertical wind shear conditions are lower ranked.
Atmospheric Low-frequency Oscillation over the Tibetan Plateau During 1997-1998 and Its Effects on Precipitation
Yang Rong, Gong Yuanfa, Xie Qiyu, Yang Jingchao
2015, 26(4): 397-408. DOI: 10.11898/1001-7313.20150402
Abstract:
Based on NCEP/DOE daily reanalysis data and conventional observations of National Meteorological Information Center, characteristics of the atmospheric low-frequency oscillation of the Tibetan Plateau monsoon in the winter of 1997-1998 and in the summer of 1998 are studied. Furthermore, the configuration of the upper and lower atmospheric low-frequency circulation system on and around the Plateau and its connection to the precipitation of China are also studied. Results mainly show that the Plateau monsoon exhibits not only a strong periodic oscillation of 30-60 days, but also a quasi-biweekly low-frequency oscillation feature, and the relevant upper troposphere circulation system in the same areas at 200 hPa mainly shows a periodic variation of 30-60 days. In the summer of 1998, there are two low-frequency oscillations of surface pressure on the Plateau and its strength has significant longitudinal change, which means that the periodic oscillation of 30-60 days gradually reduces from south to north, while the signal of quasi-biweekly oscillation becomes stronger.As for low-frequency signal of 30-60 days, when the Plateau summer monsoon is stronger (weaker), there is an obvious low-frequency cyclonic convergence (anti-cyclonic divergence) circulation system from the Plateau to the western Pacific between 25°N and 35°N, but the low-frequency anti-cyclonic (cyclonic) circulation system exists in the region south to the Plateau, from the northern Indian subcontinent and the Bay of Bengal to the northern part of South China Sea. Within the longitude scope of the Plateau (between 80°E and 90°E), there is a low-frequency wave chain from the Bay of Bengal to the eastern region of Xinjiang, which ranks as low-frequency anticyclone (cyclone)-low-frequency cyclone (anticyclone)-low-frequency anticyclone (cyclone). Within the latitude scope of the Plateau, there is low-frequency anti-cyclonic (cyclonic) circulation system at 200 hPa from the western part of the Plateau to the Sea of Japan.Influenced by low-frequency circulation system, when Plateau summer monsoon is strong, the low-frequency circulation system configuration within the latitude scope of the plateau converge on the low-level and diverge on the high-level of 200 hPa, which cause more precipitation over the eastern part of the Plateau and the middle and lower reaches of the Yangtze, while cause less precipitation over the western Sichuan Plateau and southwestern Yunnan. When the Plateau summer monsoon is weak, the low-frequency circulation system configuration diverges on the low-level and converge on the high-level, which leads to less rainfall in many parts of the contral-eastern part of the Plateau and the eastern part of China. At this time, the easterly flux from the South China Sea, southwesterly flux from the Bay of Bengal and northerly flux from the Plateau converge in the southwest of Yunnan and corresponding low-frequency circulation system of water vapor transportation also provide moisture conditions in this region, as a result, the precipitation in the southwest of Yunnan becomes more.
Preliminary Results on Long-term Soil Moisture Variation in Yunnan
Fan Feng, Duan Wei, Yang Jiakang
2015, 26(4): 409-421. DOI: 10.11898/1001-7313.20150403
Abstract:
Long-term spatial-temporal distributions of soil moisture anomalies related drought-flood events and their evolution features in Yunnan, China of recent 66 years are explored using 1948-2013 NOAA CPC 0.5°×0.5° global monthly soil moisture data, along with 125-station based monthly observed precipitation for period of 1951-2013, and monthly soil moisture observation from 22 stations for the period of 1993-2013. Comparing with precipitation, soil moisture has some unique physical properties and statistical features, such as longer memory and closer to normal distribution, making it an important component for drought-flood analyzing and monitoring. The mutual validation reveals that the gridded NOAA CPC monthly soil moisture data can capture those major observed drought-flood events very well. The preliminary results show that spatial structures of soil moisture anomaly related drought-flood events in Yunnan, China have relatively simple and large-scale features. The first four leading EOF modes can explain more than 2/3 of total variance of soil moisture variations. The soil moisture related drought-flood events also have obvious long-term variations or trends, such as from 1950s it is drier in central Yunnan and wetter in most rest parts, and then the condition gradually evolved to the opposite, from 1990s the central part of Yunnan becomes wetter than most rest parts. The drought condition tends to become worse since then, especially for the years of 2010, 2012 and 2013, when extreme drought conditions extends to almost everywhere in Yunnan. Further study on possible causes for this spatial-temporal evolution reveals some good relationships between monthly soil moisture variations and global sea surface temperature anomalies (SSTA) one or two months ago, especially in cool season. The 1st EOF mode of soil moisture anomalies, which represents soil moisture anomalies through the whole Yunnan, has good correlation with previous month's SSTA nearby the Bay of Bengal, Arab Sea, the western tropical Pacific and the remote Atlantic, and the 2nd EOF mode which reflects soil moisture anomalies related drought-flood variations from northwest to southeast Yunnan also well correlates with previous month's SSTA in the Bay of Bengal, the South China Sea, western Pacific, and the remote eastern tropical Pacific ENSO region and the tropical Atlantic. The 3rd EOF mode and 4th EOF mode of soil moisture anomalies, which present south to north and east to west drought-flood variations in Yunnan, also relate to unique SSTA in previous months.
The Persistent Impact of Winter Arctic Oscillation on the East Asian Surface Air Temperature
Dong Shi, Xiao Ziniu
2015, 26(4): 422-431. DOI: 10.11898/1001-7313.20150404
Abstract:
A statistical research of NCEP/NCAR reanalysis data and Met Office HadISST over the period of 1948-2013 is conducted to explore the influence of the winter AO on East Asian surface air temperature. The positive phase of the winter AO is characterized by weakened East Asia deep trough as well as Siberian high, low-level southerly wind field, and weakened East Asian winter monsoon resulting in temperature rise. The contrary is the case in the negative phase of the winter AO.In high latitudes, atmospheric variability in winter is very large. With probing deeply into the relationship between monthly winter AO and East Asian surface air temperature, it is found that the impact of AO in January and February can last 2 months or longer, respectively. And the impact will almost disappear in June. The effect of winter AO itself on monthly scale is not consistent. AO can only last no more than two months after self-correlation analysis. But though a large amount of ocean heat content, sea change is slow and persistent. Ocean can store abnormal information of atmosphere, and then acting on atmosphere. For the positive phase of AO, the sea surface temperature (SST) in Western Pacific and East Asian surface temperature are simultaneously abnormally high, and anomalous northeast trades lead to SST anomalies in Western Pacific, making Western Pacific carry AO signals for more than 4 months.With effects of Western Pacific, AO signals are passed continuously into East Asia. Above all, effects of SST in Western Pacific are of vital importance for the persistent impact of Arctic Oscillation on the East Asia through air-sea interaction.
Assessment and Distribution of Waterlogging Damage Risks for Melons and Vegetables in Hainan Province from October to November
Zhang Lei, Huo Zhiguo, Huang Dapeng, Wu Li
2015, 26(4): 432-441. DOI: 10.11898/1001-7313.20150405
Abstract:
Hainan, as an important agricultural zone for winter melons and vegetables in China, suffers from waterlogging, chilling and drought risks that threat production during its growth period. In order to offer guidance to reduce waterlogging damage and assure production, the theoretical framework of natural disaster risk system is implemented based on meteorological station observations from 1998 to 2011, the yield and planted area data, as well as waterlogging disaster data for melons and vegetables. A waterlogging level index system is constructed through comparing the hazard index with disaster based on the principal component analysis of four factors, i.e., precipitation, rain days, continuous rain days and maximum continuous rain days. A comprehensive waterlogging risk index model for melons and vegetables is built integrating with hazard index, damage sensitivity index, damage loss index and damage prevention capability index.Results show that the waterlogging hazard index increases from southwest to northeast, the risk probability of different level hazard index are different in regions, and the distribution of high and low risk probability are of the opposite. Due to results of disaster hazard spatial pattern, it implicates that more attention should be paid to those high hazard regions. Considering waterlogging sensitivity is partly influenced by slope gradient, the damage index increases from the central mountain to the periphery. Among three disasters, waterlogging causes most yield reduction for paprika, watermelon and cowpea which are in conformity with their biological characteristic. Taking yield loss and production status as factors to represent damage vulnerability and prevention capability, waterlogging damage loss index and prevention capability index differ in different regions. The distribution of comprehensive waterlogging risk index for melons and vegetables is similar for four kinds of melons and vegetables, which increases from southwest to northeast induced by factors such as precipitation, terrain and soil. The distribution characteristic is conformed to the real waterlogging situation in Hainan Province. Results can provide useful information which contribute to a better understanding of disaster damage risk for melons and vegetables and help for the policy formation of agro-meteorological disaster risk management.
The Analysis and Correction of Lunar Intrusion to Space View of FY-3A/MWHS
Gu Songyan, Wu Ronghua, You Ran
2015, 26(4): 442-450. DOI: 10.11898/1001-7313.20150406
Abstract:
The microwave humidity sounder (MWHS) is an important payload of FY-3A launched on 27 May 2008, for global all-weather atmosphere sounding. FY-3A/MWHS has been in operational application on orbit for more than 5 years. FY-3A/MWHS has five channels in the range of 150-191 GHz. In the normal working mode, it performs a cross-track scanning and cycle two points calibration by using of the blackbody and space views. However, the moon may occasionally appear within the cold space calibration field of view. Due to the polar orbit of the platform, it will always appear to be near the-90 phase and then have a brightness temperature of approximately 170-200 K. Its angular extent is about 0.5. Lunar radiation could therefore be significant against a cold sky background, especially for the narrow-beamed MWHS. Lunar intrusion to space view of MWHS may make a moon-glint, which typically affects about 100 scan lines per orbit for 4-5 consecutive orbits. Lunar intrusion cases are detectable as the degradation in NWP model statistics.Based on analysis of lunar intrusion cases and effects, a mitigation algorithm is developed to improve calibration results of FY-3A/MWHS in orbit.In the algorithm, the position of the moon is calculated using standard astronomical formula, and the intruding time is flagged. After that an approximation by polynomial model is devised to remove the moon-glint. On 4 July 2010, the moon-glint makes more than 1000 digital number abnormal jumping, and 20 degree degradation in brightness at sub-points line for FY-3A/MWHS 183.31±1 GHz channel.By using of the cross calibration technique between corresponding channels of FY-3/MWHS and MetOp-A/MHS, an extensive analysis is carried out to make the best fitted global SNO samples.The lunar intrusion mitigation algorithm is tested, and results show that after removing the moon-glint effects, corrected calibration results are almost the same with what got during check in orbit. The lunar intrusion mitigation algorithm works well and has been used in operation, providing the foundation of quantitative application for data of FY-3A/MWHS in NWP. Lunar intrusion also gives a clear view of the moon when it appears in the field of space view. Since there is no intervening atmosphere to attenuate the signal, which makes it possible to perform a cross-channel calibration.
Comparative Analysis on Characteristics and Mechanism for Two Types of M-component in Triggered Lightning
Xie Meng, Zhang Yang, Zhang Yijun, Lü Weitao, Zheng Dong
2015, 26(4): 451-459. DOI: 10.11898/1001-7313.20150407
Abstract:
Parameters such as amplitude, rise time, half-peak width and charge transfer is obtained by analyzing channel base current data from triggered lightning, which is acquired by GCOELD (Guangdong Comprehensive Observation Experiment of Lightning Discharge) during 2008 and 2013. Geometric mean value of amplitude, rise time, half-peak width and charge transfer from 31 samples are 301 A, 341 μs, 662 μs and 0.207 C, among which geometric mean value of amplitude is close to the result from Shandong Articicially Triggering Lightning Experiment, while rise time and half-peak width are close to results in Florida. From the histogram for parameter distribution, M-component is mostly within 400 A, the rise time is lower than 400 μs, the half-peak width is less than 1 ms, and the charge transfer is from 0.1 C to 0.3 C. Whereas, histogram of amplitude, rise time, half-peak width and charge transfer indicates portion of M-component has unusual characteristics. Combined with previous research, it's concluded that M-component can be divided into two types, by amplitude lower/higher than 1 kA. Geometric mean value of amplitude, rise time, half-peak width and charge transfer is analyzed, respectively. Two types of M-component show obvious differences, for instance, the amplitude of Type 2 M-component is almost 10 times the value of Type 1 M-component, while the rise time and half-peak width is approximately quarter of the corresponding parameter for Type 1. In general, Type 2 M-component has higher amplitude, shorter rise time and narrower half-peak width than Type 1. The relationship between M amplitude and the lag between return stroke and M-component for Type 1 and Type 2 are compared, and lags of Type 2 M-components are shorter than 50 ms, shorter than lags of Type 1 M-components as a whole. It possibly indicates that the lower the amplitude of M-component is, the longer the lag is. With M-component two-wave model, the electric field are calculated. By configuring incident wave velocity and reflected wave velocity to various values, it's found that the result is consistent with measured electric field, but the incident velocity is always smaller than reflected velocity for both Type 1 and Type 2. The ratio between incident wave velocity and reflected wave velocity for Type 1 is larger than that of Type 2. Based on analysis for M-component characteristics and M-component classification, two types of M-component may correspond with streamer occurred by breakdown in channel branch into main channel and breakdown within part of the lightning channel, indicating Type 1 M-component has some differences with Type 2 M-component in mechanism.
The Error Wind Data Processing Based on Radial Power Spectrum of Wind Profiler Radar
Chen Haojun, Huang Xingyou, Sun Jing, Sun Juan, Yin Chunguang, Zheng Jie, Wang Qindian, Xue Hao
2015, 26(4): 460-471. DOI: 10.11898/1001-7313.20150408
Abstract:
Wind profiler radar is a new generation of radio sounding wind detecting system, which takes atmospheric turbulence backscattered signal as its main detecting object. It is the most direct source to obtain high-altitude wind data in addition to the sounding data. In recent years, researches on the wind profiler radar detection are widely carried out during precipitation periods. It shows that the signal to noise ratio (SNR), the refractive index structure constant (CN2), horizontal speed, vertical wind speed and other information provided by the wind profiler could help to know the precipitation process, and clearly reflect the start time and the intensity of precipitation. The real-time high resolution radial power spectrum data provided by wind profiler radar, can not only be used to extract the wind data, but also estimate the height range of freezing layer and verify quality control performance of the wind profiler radar software. The application of wind profiler radar data is no longer limit to only study the clear air atmosphere.However, during a precipitation process, especially at the beginning of the precipitation, uneven rainfall leads to inconsistent beams in the space, and the quality control (QC) algorithm of the software used in radar cannot identify and eliminate all interference made by precipitation, leading to horizontal wind data errors.In order to improve data quality, the radial wind power spectrum data of wind profiler radar is analyzed to find out QC problems and identify and remove erroneous data. First, under the premise of fully knowing the principle of software QC method, the location and cause of software QC judgment errors are identified by progressively comparing the radial power spectrum data of the high and low mode. And then, the radial power spectrum data in problem period is reprocessed. Finally, the wind data is recalculated. Case analysis shows that the error wind data processing based on radial power spectrum of wind profiler radar could improve software QC methods and improve the quality of wind profiler radar data.
A Modified Method of Removing Ground Clutter from Wind Profiler Radar Based on Adaptive Wavelet Threshold
Zhang Fugui, Fan Xiao, He Jianxin
2015, 26(4): 472-481. DOI: 10.11898/1001-7313.20150409
Abstract:
Wind profiler radar (WPR) can be used to retrieve real-time atmospheric wind field data of high resolution. Backscattered echo caused by irregularities of atmospheric refractive index is received by radar antenna and wind velocities is calculated with Doppler frequency shifting speed formula. It is widely used in fields of very short-term weather forecasting, airport operations and public protection, air pollution monitoring, wind field analyses and forecasts of toxic plume trajectories resulting from chemical or nuclear incidents. As a result of being widely used in different situations, WPR is always sited near the city with a large population and complicated geographical environment. Transmission of electromagnetic wave during WPR detecting period is often interfered by various clutters that contaminate WPR data introduce bias in moments and wind velocity estimation. Of all clutters, ground clutter is the primary source because it happens more often than the others. Ground clutter is radar return from more or less stationary targets such as trees, buildings near the cited place. How to eliminate the influence of ground clutter is a most concerned aspect. Ground clutter mainly concentrates around the zero-frequency and it has high amplitude on the power spectrum. The most frequently used methods, such as traditional wavelet threshold processing and zero-frequency elimination of 3 points, both have the ability to separate the meteorology echo from the ground clutter when the turbulent peak is away from the zero-frequency and not covered with ground clutter peak. However, when the near zero-frequency echo is taken into consideration, both of the traditional methods meet their limitation. Based on the wavelet high frequency coefficients, a method of determining threshold adaptively is proposed and the validation of the method is done by using of simulated data and WPR measured data. The corresponding power spectrum before and after self-adapting wavelet threshold processing are compared. Results show that this method performs well even when the signal is close to the zero-frequency and covered completely. Meanwhile, the method has some important features, such as simple theory, small amount of calculation and easy to implement. Cases analysis shows that self-adapting threshold processing can increase the accuracy of peak identification, also provide approach and basis for improving the WPR products.
Observational Study on the Ground-based UVI at Dangxiong of Tibet
Chen Shu, Zheng Xiangdong, Lin Weili, Zhang Yong, Zaxi Dawa, Qi Donglin
2015, 26(4): 482-491. DOI: 10.11898/1001-7313.20150410
Abstract:
Factors of solar zenith angle (SZA), cloud, ozone and snow cover modifying the surface ultraviolet index (UVI) in the Tibetan Plateau are presented by the TUV model simulations and the two-year continuous ground-based measurements at Dangxiong (30.48°N, 91.10°E, 4200 m a.s.l) from September 2009 to August 2011. Results show that the key factors affecting the UVI over the Tibetan region are SZA and cloud. Variations of cloud-free surface UVI can be characterized exactly as a simple empirical SZA function. The UVI cloud modification factor (CMF) generally reduces by 46% as the cloud amount increases from 0 to 100%. CMF might increase by 3%-6%, or even by 40% in individual cases if the solar disk is partly masked with broken clouds. The ozone valley enhances 12% summer surface UVI compared to plain regions of the similar latitudes. The winter short-term thin snow coverage could enhance 16% or less surface UVI, and this enhancement is lower than that from the simulations (23%). UVI attenuation caused by aerosols with optical depth of 0.02-0.1 is no more than 3%. As compared with UVI measured at Lhasa (29.67°N, 91.13°E, 3650 m a.s.l), Tuotuohe (34.22°N, 92.43°E, 4500 m a.s.l) and Waliguan (36.29°N, 100.90°E, 3810 m a.s.l), the difference of site-altitude is a key factor influencing the UVI. Under the same SZA conditions, the summer UVI at Lhasa is 7%-10% higher than that at Waliguan due to the southern thinner ozone layer, the ozone valley. Comparison with satellite-derived product shows that, averagely, the OMI-UVI is 80% higher than the ground-based values at Dangxiong but only 8.6% higher under cloud-free circumstances. The OMI-UVIs are all above 65% higher than those ground-based measurements at the other 3 sites but their cloud-free values are only 13%, 9% and 50% higher at Tuotuohe, Waliguan and Lhasa, respectively. Clouds and geographical mismatches between the satellite pixel and fixed ground-based observation site are supposed to be the main factors of higher space-based UVI values, particularly over Lhasa. As the ground-based UVI is more than 14, the coincident space-based UVI is generally 3% lower at Dangxiong owning to the broken clouds strengthening the in-situ radiation.
Application and Verification of Accumulated Temperature Effects on Daily Peak Load and Daily Valley Load of Power
Fu Guiqin, You Fengchun, Cao Xin, Jia Junmei
2015, 26(4): 492-499. DOI: 10.11898/1001-7313.20150411
Abstract:
In order to meet needs for electric power of meteorological service, an analysis is made on the correlation between meteorological elements and electrical loads of electric network in Hebei Province. The meteorological data and electrical load data from May to September during 2001-2010 are used, and they are divided into sunny hot weather and muggy weather. Compared to the sunny hot weather, it shows that the daily peak load and daily valley load are increased significantly in muggy weather lasting three days or more. When daily maximum temperature reaches 32℃, daily peak load of power increase rapidly in Hebei Province, and 32, 35℃ and 38℃ of daily maximum temperature are three sensitive points for daily peak load of power to air temperature variation. During periods with daily maximum temperature more than or equal to 35℃, the daily peak load of power varies greatly according to the air temperature. When daily maximum temperature exceeds 38℃, considering 1℃ rising of daily maximum temperature, the daily peak load of power would increase 9.4%, and the air-conditioning cooling load of power would reach 50% of the daily peak load. When daily minimum temperature reaches 25℃, daily valley load of power increases rapidly, and 25℃ of daily minimum temperature is the sensitive point of daily valley load of power to air temperature variation. Introducing accumulated temperature effect as forecast factor, a meteorological electricity prediction model is established by using the multiple regression method, which can predict the peak and valley of meteorological electricity loads. The model is validated using historic data from 2011 to 2013, the average relative error of daily peak load is 4.8%, and that of the daily valley load is 3.5%, showing good prediction accuracy. The proposed model has reference significance for electric power dispatching.
Design and Implementation of China Integrated Meteorological Information Sharing System (CIMISS)
Xiong Anyuan, Zhao Fang, Wang Ying, Zhang Xiaoying, Gao Feng, Deng Li, Tan Xiaohua, Ma Qiang
2015, 26(4): 500-512. DOI: 10.11898/1001-7313.20150412
Abstract:
Meteorological data play a fundamental role in processes of meteorological operations and services. In recent 20 years, China has rapidly developed traditional and newly observational systems, which produce a large volume of meteorological data and products. To meet requirements of data management and services, China Integrated Meteorological Information Sharing System (CIMISS) is developed by National Meteorological Information Center of China Meteorological Administration. The design principle, system structure and data flow, and core technologies of this system are introduced and illustrated in detail. CIMISS is composed of five sub-systems, which are China Telecommunication System (CTS), Data Processing Center (DPC), Service-Oriented Database (SOD), Global Data Sharing (GDS), Monitoring and Control Platform (MCP). CIMISS is designed for undertaking a series of operations of meteorological data collecting, processing, storage, retrieval and dissemination. Data cover all real-time and historical meteorological observations and products, including 14 classes that are surface, upper-air, solar radiation, oceanic meteorology, agro-meteorology, radar, satellite, proxy climate, atmospheric chemistry, numeric model analysis and forecast, scientific experiment, meteorological disaster, meteorological service product and the others. Data cover the geographic area from China to global, and the period from 1951 to now. Real-time data come from all kind of meteorological observation networks in China, and the Global Telecommunication System of World Meteorological Organization.A set of information technologies are introduced and developed to design and implement the system, including inner-system message switching based on message middleware and the parallel file system, classification and representation of meteorological data, the dynamic extension of data processing scheduling and algorithms, the design and application of 3 types of metadata, the management of common configuration information, monitoring and controlling for whole procedures of operational flow, service-oriented data storage strategy, the unified accessing view and application programming interface.CIMISS will manage all kinds of operational meteorological data used in national and provincial meteorological operations and services, and supply data application environment for operations of national service centers and 31 provincial service centers. Users can access the data by Web page and by application programming interface (API).