Volume 45,Issue 6,2017 Table of Contents
2017, 45(6):955-961.
Abstract:
Weather radar can provide early warning information of strong convective weather disasters such as hail and tornado. There are problems that radar provides only warning products on the site, and strong weather detection algorithms are not locally optimized. This paper studies the radar warning information integration technology to provide timely and efficient information for a wide range of strong convective weather. The statistical analysis of the 0 ℃ level height data of 3 years indicates that the 0 ℃ level height should be adjusted dynamically in 3 to 5 km for the Hail Detection Algorithm, and a dynamic localization comprehensive quality control method is put forward. Through the statistical analysis before and after quality control, it is shown that quality control can effectively reduce the false alarm rate of radar warning by more than 95%. The test results of lightning observation data show that the quality of radar warning information is better with the lightning distribution. Good application effectiveness is achieved in the 2016623 Yancheng tornado disaster weather warning based on the network integration and the integrated application of quality control.
Weather radar can provide early warning information of strong convective weather disasters such as hail and tornado. There are problems that radar provides only warning products on the site, and strong weather detection algorithms are not locally optimized. This paper studies the radar warning information integration technology to provide timely and efficient information for a wide range of strong convective weather. The statistical analysis of the 0 ℃ level height data of 3 years indicates that the 0 ℃ level height should be adjusted dynamically in 3 to 5 km for the Hail Detection Algorithm, and a dynamic localization comprehensive quality control method is put forward. Through the statistical analysis before and after quality control, it is shown that quality control can effectively reduce the false alarm rate of radar warning by more than 95%. The test results of lightning observation data show that the quality of radar warning information is better with the lightning distribution. Good application effectiveness is achieved in the 2016623 Yancheng tornado disaster weather warning based on the network integration and the integrated application of quality control.
2017, 45(6):962-967.
Abstract:
A technique of online calibration based on SYSCAL for CINRAD weather radar adopts is introduced, which can dynamically test and adjust the measurement errors for the performance variation of transmitting and receiving channels in a running radar, and the calibration has a good performance and an appropriate time interval. A detailed analysis is presented by the theoretical deduction of the online calibration technique of CINRAD weather radar reflectivity factor. The realization methods of the technique and corresponding calibration methods and its derivation in CINRAD/SA weather radar are described. The actual effect is tested and analyzed with a calibration example of the Wuhan weather radar. Some problems of the online calibration are listed. To master the principles and the technique of the online calibration is useful for correctly implementing calibration, ensuring the echo quality and improving the ability to diagnose the radar faults.
A technique of online calibration based on SYSCAL for CINRAD weather radar adopts is introduced, which can dynamically test and adjust the measurement errors for the performance variation of transmitting and receiving channels in a running radar, and the calibration has a good performance and an appropriate time interval. A detailed analysis is presented by the theoretical deduction of the online calibration technique of CINRAD weather radar reflectivity factor. The realization methods of the technique and corresponding calibration methods and its derivation in CINRAD/SA weather radar are described. The actual effect is tested and analyzed with a calibration example of the Wuhan weather radar. Some problems of the online calibration are listed. To master the principles and the technique of the online calibration is useful for correctly implementing calibration, ensuring the echo quality and improving the ability to diagnose the radar faults.
2017, 45(6):968-973.
Abstract:
Currently, the frequency band 1695-1710 MHz is under consideration by some administrations as the potential candidate band for IMT systems under Agenda Item 11 of WRC15 According to the ITUR Radio Regulations (Edition of 2012), the band 1695-1710 MHz is allocated to the meteorological satellite service (spacetoearth) on a primary basis, Chinese FY geostationary (GSO) and nonegeostationary (NGSO) satellites also use this band for data transmission. In order to ensure that no unacceptable interference is caused by IMT base stations into FY satellites in the band 1695-1710 MHz, this study provides an analysis of the frequency compatibility from IMT base stations to GSO and NGSO meteorologicalsatellite systems, respectively. Based on the interference simulation analysis results, it appears that sharing between meteorological satellite service and IMT base stations in this frequency band is not compatible.
Currently, the frequency band 1695-1710 MHz is under consideration by some administrations as the potential candidate band for IMT systems under Agenda Item 11 of WRC15 According to the ITUR Radio Regulations (Edition of 2012), the band 1695-1710 MHz is allocated to the meteorological satellite service (spacetoearth) on a primary basis, Chinese FY geostationary (GSO) and nonegeostationary (NGSO) satellites also use this band for data transmission. In order to ensure that no unacceptable interference is caused by IMT base stations into FY satellites in the band 1695-1710 MHz, this study provides an analysis of the frequency compatibility from IMT base stations to GSO and NGSO meteorologicalsatellite systems, respectively. Based on the interference simulation analysis results, it appears that sharing between meteorological satellite service and IMT base stations in this frequency band is not compatible.
2017, 45(6):974-979.
Abstract:
For the bad reception of polar orbit satellite, the impact of the signal intensity of the polar satellite on the demodulator and the corresponding counter measures are studied. According to the signal characteristics of the polarorbit meteorological satellite and the power level, as well as the circuit principle diagram of the satellite demodulator, the reasons for satellite reception level changing beyond the scope of the modulator are analyzed, and the countermeasure is put forward. The measured results show that the signal level can be controlled at an appropriate value steadily by adding an automatic gain controller and an attenuator before the demodulator. The abnormal reception of the HRPT (High Resolution Picture Transmission) data is effectively solved and the quality of the satellite cloud picture receiving is improved. The solution is applicable in equipment maintenance.
For the bad reception of polar orbit satellite, the impact of the signal intensity of the polar satellite on the demodulator and the corresponding counter measures are studied. According to the signal characteristics of the polarorbit meteorological satellite and the power level, as well as the circuit principle diagram of the satellite demodulator, the reasons for satellite reception level changing beyond the scope of the modulator are analyzed, and the countermeasure is put forward. The measured results show that the signal level can be controlled at an appropriate value steadily by adding an automatic gain controller and an attenuator before the demodulator. The abnormal reception of the HRPT (High Resolution Picture Transmission) data is effectively solved and the quality of the satellite cloud picture receiving is improved. The solution is applicable in equipment maintenance.
2017, 45(6):980-987.
Abstract:
Based on the statistics of normal and abnormal frequencies of the monitoring status and data quality of ground temperature, pressure, temperature, humidity, wind and precipitation from newtype automatic meteorological stations, the correlation analysis between observation data and equipment status information is conducted, and the accuracy rate and error rate are calculated in this paper. The results show that there is a good consistency between observational data and communication status, equipment selftest status and sensors, with normalaccuracy rate exceeding 96%, while the consistency between observational data and the collector, communication interface, counter, AD and motherboard temperature, etc., is poor, with abnormalaccuracy rate less than 3%. The operational status information of domestic newtype AWSs is utilized for the quality judgment of observation elements for the first time. Although there are still certain problems in application needing improvement, this study is of significance for improving the data quality control methods and promoting the authenticity and availability of AWS’s data.
Based on the statistics of normal and abnormal frequencies of the monitoring status and data quality of ground temperature, pressure, temperature, humidity, wind and precipitation from newtype automatic meteorological stations, the correlation analysis between observation data and equipment status information is conducted, and the accuracy rate and error rate are calculated in this paper. The results show that there is a good consistency between observational data and communication status, equipment selftest status and sensors, with normalaccuracy rate exceeding 96%, while the consistency between observational data and the collector, communication interface, counter, AD and motherboard temperature, etc., is poor, with abnormalaccuracy rate less than 3%. The operational status information of domestic newtype AWSs is utilized for the quality judgment of observation elements for the first time. Although there are still certain problems in application needing improvement, this study is of significance for improving the data quality control methods and promoting the authenticity and availability of AWS’s data.
2017, 45(6):988-994.
Abstract:
From January to May 2015 CMA Meteorological Observation Centre conducted an experiment of cloud observation by one Kaband solidstate millimeter wave ceilometer (HT101) and two kinds of laser ceilometers (CYY2B and HYCL51). During the experiment taking the heights of Lband sounding balloons passing through the cloud base as the standards of the cloud base height, the whole sky infrared cloud measuring system and the automatic meteorological station as auxiliary equipment, the different types of ceilometers are analyzed in the aspects of completeness, accuracy, data acquisition rate, and weather adaptability. The results show that the detection capability of HT101 is better than CYY2B and HYCL51 Main results are as follows: (1) The data acquisition rate of HT101 is the highest. (2) HT101 has the higher detection accuracy of cloud base heights than CYY2B and HYCL51 (3) HT101 has the stronger capability to detect cloud top heights. (4) HT101 has the better weather adaptability than CYY2B and HYCL51
From January to May 2015 CMA Meteorological Observation Centre conducted an experiment of cloud observation by one Kaband solidstate millimeter wave ceilometer (HT101) and two kinds of laser ceilometers (CYY2B and HYCL51). During the experiment taking the heights of Lband sounding balloons passing through the cloud base as the standards of the cloud base height, the whole sky infrared cloud measuring system and the automatic meteorological station as auxiliary equipment, the different types of ceilometers are analyzed in the aspects of completeness, accuracy, data acquisition rate, and weather adaptability. The results show that the detection capability of HT101 is better than CYY2B and HYCL51 Main results are as follows: (1) The data acquisition rate of HT101 is the highest. (2) HT101 has the higher detection accuracy of cloud base heights than CYY2B and HYCL51 (3) HT101 has the stronger capability to detect cloud top heights. (4) HT101 has the better weather adaptability than CYY2B and HYCL51
2017, 45(6):995-1001.
Abstract:
The automatic observation of precipitation weather phenomena is an important part of the ground observation automation. In order to eliminate the subjectivity of manual observation and improve the integrity and timeliness of precipitation data, the China Meteorological Administration Meteorological Observation Center selected 18 laser raindrop spectrometers from 6 manufacturers, which participated in the 3month contrast experiment on precipitation weather phenomena meters in Beijing and Changsha. This paper is focusing on the experiment equipment, test data analysis and summary, mainly from the experiment location, principles, standards, methods and other aspects. The average capture rate of the tested equipment is not less than 97% for precipitation intensity of greater than 01 mm/h, and not less than 84% for precipitation intensity of less than 01 mm/h. The consistent rate of the tested equipment went through a process of increasing firstly and then decreasing with the increase of precipitation. The test results of the tested equipment are relatively ideal for hail phenomenon, and the average false alarm rate of all the tested equipment is less than 05% for hail phenomenon, while the observations of drizzle and unknown phenomena still need improvement. The misstatement rate is negatively correlated with the precipitation intensity. The smaller the precipitation intensity is, the higher the misstatements rate. The results provide hopefully a reference for the relevant technicians.
The automatic observation of precipitation weather phenomena is an important part of the ground observation automation. In order to eliminate the subjectivity of manual observation and improve the integrity and timeliness of precipitation data, the China Meteorological Administration Meteorological Observation Center selected 18 laser raindrop spectrometers from 6 manufacturers, which participated in the 3month contrast experiment on precipitation weather phenomena meters in Beijing and Changsha. This paper is focusing on the experiment equipment, test data analysis and summary, mainly from the experiment location, principles, standards, methods and other aspects. The average capture rate of the tested equipment is not less than 97% for precipitation intensity of greater than 01 mm/h, and not less than 84% for precipitation intensity of less than 01 mm/h. The consistent rate of the tested equipment went through a process of increasing firstly and then decreasing with the increase of precipitation. The test results of the tested equipment are relatively ideal for hail phenomenon, and the average false alarm rate of all the tested equipment is less than 05% for hail phenomenon, while the observations of drizzle and unknown phenomena still need improvement. The misstatement rate is negatively correlated with the precipitation intensity. The smaller the precipitation intensity is, the higher the misstatements rate. The results provide hopefully a reference for the relevant technicians.
2017, 45(6):1002-1005.
Abstract:
Based on the observation data of the global solar radiation between Holland CM6B and Domestic Instrumemts at the same time. Using the statistical analysis method, the collected data from two sets of instruments are analyzed, and the possible reasons for the differences are discussed. The results show that: the observed data from the domestic instrument and Holland CM6B pyranometer have small differences. The average daily value is 013 MJ〖DK〗·m-2, and the difference of standard deviation is 075 MJ〖DK〗·m-2. The monthly accumulative global solar radiation differences between two sets of instruments have obvious seasonal characteristics. The spring and summer differences are slightly higher than those of autumn and winter season; the overall variation shows a gentle trend; and all the data are appliacable. The domestic global solar radiation is more reliable. The differences in manufacturers, models, parameter sensitivity, the errors of calibration, and manual correction data are the main reasons for the significant difference between two sets of instrument.
Based on the observation data of the global solar radiation between Holland CM6B and Domestic Instrumemts at the same time. Using the statistical analysis method, the collected data from two sets of instruments are analyzed, and the possible reasons for the differences are discussed. The results show that: the observed data from the domestic instrument and Holland CM6B pyranometer have small differences. The average daily value is 013 MJ〖DK〗·m-2, and the difference of standard deviation is 075 MJ〖DK〗·m-2. The monthly accumulative global solar radiation differences between two sets of instruments have obvious seasonal characteristics. The spring and summer differences are slightly higher than those of autumn and winter season; the overall variation shows a gentle trend; and all the data are appliacable. The domestic global solar radiation is more reliable. The differences in manufacturers, models, parameter sensitivity, the errors of calibration, and manual correction data are the main reasons for the significant difference between two sets of instrument.
9 Cloudiness Recognition Algorithm of GroundBased Visible AllSky Images Based on Image Processing
2017, 45(6):1006-1010.
Abstract:
In order to further distinguish the clouds and the background and improve cloud recognition， this paper proposes an algorithm to improve the quality of cloud images based on image restoration and enhancement techniques. First, a dark channel priordehazing algorithm is employed for image restoration. Then, the features are enhanced using the brightness histogram equalization algorithm. Finally, the two algorithms are combined by using image enhancement after image restoration. At the same time, the four conditions of thin cloud in low visibility, thick cloud in low visibility, thin cloud in high visibility, and thick cloud in high visibility are discussed, respectively. According to the simulation results, except that a single image restoration on thin clouds in high visibility has reduced cloud recognition, the proposed algorithm has significantly improved the image quality and cloud recognition. In addition, the image quality and cloud recognition can be further enhanced using the image restoration and enhancement techniques together, and there are more improvements on thin clouds and clouds in low visibility.
In order to further distinguish the clouds and the background and improve cloud recognition， this paper proposes an algorithm to improve the quality of cloud images based on image restoration and enhancement techniques. First, a dark channel priordehazing algorithm is employed for image restoration. Then, the features are enhanced using the brightness histogram equalization algorithm. Finally, the two algorithms are combined by using image enhancement after image restoration. At the same time, the four conditions of thin cloud in low visibility, thick cloud in low visibility, thin cloud in high visibility, and thick cloud in high visibility are discussed, respectively. According to the simulation results, except that a single image restoration on thin clouds in high visibility has reduced cloud recognition, the proposed algorithm has significantly improved the image quality and cloud recognition. In addition, the image quality and cloud recognition can be further enhanced using the image restoration and enhancement techniques together, and there are more improvements on thin clouds and clouds in low visibility.
2017, 45(6):1011-1016.
Abstract:
With the purpose of distinguishing and revising the abnormal values of lightning location data and improving the accuracy of lightning location products, this study uses such methods as the Tyson polygon, the hypothesis test of data distribution, abnormal values (with the FiveNumber Summary) to establish a technique that associates with the manual observation of lightning days to distinguish the abnormal grid data of lightning density location on the lightning positioning gird density map. The application case of Fujian Province is discussed. The results show that there are certain detection errors or data loss of lightning location data in the northern and western parts of Fujian Province; the correction is conducted in the areas with unusual values by the artificial observation of lightning data; the method can be used in the areas with less lightning location instruments to distinguishes and optimizes the abnormal values of lightning location data.
With the purpose of distinguishing and revising the abnormal values of lightning location data and improving the accuracy of lightning location products, this study uses such methods as the Tyson polygon, the hypothesis test of data distribution, abnormal values (with the FiveNumber Summary) to establish a technique that associates with the manual observation of lightning days to distinguish the abnormal grid data of lightning density location on the lightning positioning gird density map. The application case of Fujian Province is discussed. The results show that there are certain detection errors or data loss of lightning location data in the northern and western parts of Fujian Province; the correction is conducted in the areas with unusual values by the artificial observation of lightning data; the method can be used in the areas with less lightning location instruments to distinguishes and optimizes the abnormal values of lightning location data.
2017, 45(6):1017-1021.
Abstract:
According to the characteristics of various meteorological data types, large amount of information and high precision, the traditional relational database system has such problems as load saturation, unsatisfactory read and write performance and so on in storage processing and data reading. Based on the researches on cloud data storage technology and the characteristics of meteorological data, the meteorological data storage and processing method based on the cloud data storage platform is designed. Based on the structural and semi/unstructured characteristics of meteorological data, the structured meteorological data is stored in a cloud relational database. The NoSQL object database is used to store the semi/unstructured meteorological data. Moreover, the block compression technology is applied to meteorological data storage and transmission. The results show that the proposed method has good storage and transmission efficiency and can meet the requirements in storage query and processing speed of largescale meteorological data in the operational application.
According to the characteristics of various meteorological data types, large amount of information and high precision, the traditional relational database system has such problems as load saturation, unsatisfactory read and write performance and so on in storage processing and data reading. Based on the researches on cloud data storage technology and the characteristics of meteorological data, the meteorological data storage and processing method based on the cloud data storage platform is designed. Based on the structural and semi/unstructured characteristics of meteorological data, the structured meteorological data is stored in a cloud relational database. The NoSQL object database is used to store the semi/unstructured meteorological data. Moreover, the block compression technology is applied to meteorological data storage and transmission. The results show that the proposed method has good storage and transmission efficiency and can meet the requirements in storage query and processing speed of largescale meteorological data in the operational application.
2017, 45(6):1022-1026.
Abstract:
Using the C# program language and WebService interface, a realtime contour technology solution is developed for smart mobile devices. This solution changes meteorological grid data into contour data by the contour algorithm. Contour data are converted into binary data which is encoded and compressed through coding and compression techniques. The binary contour data is downloaded into the mobile devices by the WebService interface, and by using of WebGIS API functions and mobile terminals, the contours and choroplethic map are drawn in real time and displayed on screen as the vector layer. The application results show that the solution can avoid image fuzzy and image distortion and display more detailed and accurate and clear meteorological information, comparing to displaying a picture on screen.
Using the C# program language and WebService interface, a realtime contour technology solution is developed for smart mobile devices. This solution changes meteorological grid data into contour data by the contour algorithm. Contour data are converted into binary data which is encoded and compressed through coding and compression techniques. The binary contour data is downloaded into the mobile devices by the WebService interface, and by using of WebGIS API functions and mobile terminals, the contours and choroplethic map are drawn in real time and displayed on screen as the vector layer. The application results show that the solution can avoid image fuzzy and image distortion and display more detailed and accurate and clear meteorological information, comparing to displaying a picture on screen.
2017, 45(6):1027-1035.
Abstract:
The sudden track change of typhoons, including its moving direction and speed, is still a difficult problem in operational typhoon track forecasting. Its great track error in operation often results in the failure of typhoon defense, which is related to the lack of understanding on its mechanisms. This paper reviews and summarizes the research achievements and latest progresses in the sudden track change of typhoons. From the points of the interaction between typhoon and multiscale systems, the inner dynamic mechanism and the situation of the underlying surface, the main environmental factors, physical processes, dynamic and thermal structural characteristics related to sudden track change of typhoons are summarized. Moreover, the probability of the sudden track change of typhoons, forecast techniques and existing problems are investigated. Some research issues about sudden track change of typhoons that need to be concerned about are discussed.
The sudden track change of typhoons, including its moving direction and speed, is still a difficult problem in operational typhoon track forecasting. Its great track error in operation often results in the failure of typhoon defense, which is related to the lack of understanding on its mechanisms. This paper reviews and summarizes the research achievements and latest progresses in the sudden track change of typhoons. From the points of the interaction between typhoon and multiscale systems, the inner dynamic mechanism and the situation of the underlying surface, the main environmental factors, physical processes, dynamic and thermal structural characteristics related to sudden track change of typhoons are summarized. Moreover, the probability of the sudden track change of typhoons, forecast techniques and existing problems are investigated. Some research issues about sudden track change of typhoons that need to be concerned about are discussed.
2017, 45(6):1036-1042.
Abstract:
A new method for probabilistic precipitation forecasts with dynamic weights is proposed. First, a scoring model for weight distribution is established and the forecast accuracy calculated from radar extrapolation and numerical model prediction is evaluated. Second, an improved method based on the Brier scoring is presented, which takes into account the size of the precipitation area and precipitation, and reduces the sensitivity to the number of samples. Third, according to the scores of different lead times, the weights of two kinds of forecasting methods are dynamically allocated in different forecast lead time. In the experimental part, the Brier and other ratings show that the prediction of each lead time is similar to the radar extrapolation or the numerical model, and even has a higher technical score.
A new method for probabilistic precipitation forecasts with dynamic weights is proposed. First, a scoring model for weight distribution is established and the forecast accuracy calculated from radar extrapolation and numerical model prediction is evaluated. Second, an improved method based on the Brier scoring is presented, which takes into account the size of the precipitation area and precipitation, and reduces the sensitivity to the number of samples. Third, according to the scores of different lead times, the weights of two kinds of forecasting methods are dynamically allocated in different forecast lead time. In the experimental part, the Brier and other ratings show that the prediction of each lead time is similar to the radar extrapolation or the numerical model, and even has a higher technical score.
2017, 45(6):1043-1048.
Abstract:
Atmospheric advection equations are generally used for numerical forecast on the grid field. It is rarely applied to the extrapolation of discrete elements. The extrapolation of model discrete elements not only makes the data filling in time more meaningful, but also lays the foundation for forecasting elements of a site. The model, based on discrete site characteristics, reforms the advection equation to get the wind speed of sites and gradient eigenvectors. The Gauss expression of the likelihood probability of the advection terms is fitted by the frequency statistics, and the numerical solution of the newstyle advection equation is calculated. Through the singlepoint and multipoint actual tests, the specific application characteristics of the model are obtained, and a real data filling case is given. The results indicate that it worked well. The model is compact, efficient and easy to use, has good universality. As a general mathematical model, it provides a new idea for the element prediction at discrete points.
Atmospheric advection equations are generally used for numerical forecast on the grid field. It is rarely applied to the extrapolation of discrete elements. The extrapolation of model discrete elements not only makes the data filling in time more meaningful, but also lays the foundation for forecasting elements of a site. The model, based on discrete site characteristics, reforms the advection equation to get the wind speed of sites and gradient eigenvectors. The Gauss expression of the likelihood probability of the advection terms is fitted by the frequency statistics, and the numerical solution of the newstyle advection equation is calculated. Through the singlepoint and multipoint actual tests, the specific application characteristics of the model are obtained, and a real data filling case is given. The results indicate that it worked well. The model is compact, efficient and easy to use, has good universality. As a general mathematical model, it provides a new idea for the element prediction at discrete points.
2017, 45(6):1049-1057.
Abstract:
The daily observational data and forecast data of the European center model from 2000 to 2014 of 1st to 31th May of 121 meteorological stations are used to analyze the dryhot wind events in Henan Province,and the classification models of dryhot wind weather are summarized. The objective forecasting method of dryhot wind of Henan Province by using multiple regression method is established. The results show that the main circulation patterns for dryhot wind in Henan province can be divided into three types: northwest airflow type, high pressure ridge type, and zonal circulation type. Through multiple regression analysis, the daily maximum temperature forecast factors are screened: the highest temperature of previous day, the lowest temperature of the day, 08:00 temperature, and EC850 hPa 24hour temperature forecast. The relative humidity forecast factors are: EC850 hPa 24hours relative humidity forecast, 14:00 relative humidity of the previous day, and 08:00 dew point temperature of the day. The wind speed forecast factor is: EC finegrid 10 meters wind forecast in the past 3 hours. The forecast equations of temperature, humidity and wind speed are established. The dryhot wind weather forecast equation is used for 2014 for verification. The results show that the weak dryhot wind forecast TS score is 62%, and strong dryhot wind forecast TS score is 64%.
The daily observational data and forecast data of the European center model from 2000 to 2014 of 1st to 31th May of 121 meteorological stations are used to analyze the dryhot wind events in Henan Province,and the classification models of dryhot wind weather are summarized. The objective forecasting method of dryhot wind of Henan Province by using multiple regression method is established. The results show that the main circulation patterns for dryhot wind in Henan province can be divided into three types: northwest airflow type, high pressure ridge type, and zonal circulation type. Through multiple regression analysis, the daily maximum temperature forecast factors are screened: the highest temperature of previous day, the lowest temperature of the day, 08:00 temperature, and EC850 hPa 24hour temperature forecast. The relative humidity forecast factors are: EC850 hPa 24hours relative humidity forecast, 14:00 relative humidity of the previous day, and 08:00 dew point temperature of the day. The wind speed forecast factor is: EC finegrid 10 meters wind forecast in the past 3 hours. The forecast equations of temperature, humidity and wind speed are established. The dryhot wind weather forecast equation is used for 2014 for verification. The results show that the weak dryhot wind forecast TS score is 62%, and strong dryhot wind forecast TS score is 64%.
2017, 45(6):1058-1064.
Abstract:
Based on the six outputs of models estimated by the multimodel downscaling ensemble prediction system (MODES), temperature and precipitation were evaluated in the prediction performance and analyzed by using the symbol consistency method (Pc). According to the results of the evaluation, the equalweight averaging scheme and the optimal scheme are used to statistically integrate the six model products for local application from 2012 to 2015The results indicate that the prediction performance of the model products is different, and the prediction performance of ECMWF is higher than that of NCC and NCEP. By comparing the two schemes, the scores of the optimal scheme are higher than the average score of six outputs and the equalweight averaging scheme no matter temperature or precipitation. Meanwhile, the scores of the optimal scheme are higher than those of the released prediction products. Therefore, using the optimal scheme can effectively improve the effect of MODES on predicted performance.
Based on the six outputs of models estimated by the multimodel downscaling ensemble prediction system (MODES), temperature and precipitation were evaluated in the prediction performance and analyzed by using the symbol consistency method (Pc). According to the results of the evaluation, the equalweight averaging scheme and the optimal scheme are used to statistically integrate the six model products for local application from 2012 to 2015The results indicate that the prediction performance of the model products is different, and the prediction performance of ECMWF is higher than that of NCC and NCEP. By comparing the two schemes, the scores of the optimal scheme are higher than the average score of six outputs and the equalweight averaging scheme no matter temperature or precipitation. Meanwhile, the scores of the optimal scheme are higher than those of the released prediction products. Therefore, using the optimal scheme can effectively improve the effect of MODES on predicted performance.
2017, 45(6):1065-1069.
Abstract:
As the T639 numerical forecasting model has a certain deviation in the specific regional forecast, in order to make better use of this model to make the regional station temperature forecast in Jimo, Shandong, we developed a revised method, which can be put into the actual operation to improve the forecast accuracy and relative error of daily maximum (minimum) air temperature, using the T639 2 meter temperature numerical forecast products during 24 hours and the observations in 8 regional automatic stations in Jimo from January 2013 to December 2015 Based on the contrast verification, it is concluded that the comprehensive correction is the most accurate method among the seasonal correction, comprehensive correction, wind direction correction, and wind velocity correction, which is combined with wind direction and wind velocity forecast and terrain zoning.
As the T639 numerical forecasting model has a certain deviation in the specific regional forecast, in order to make better use of this model to make the regional station temperature forecast in Jimo, Shandong, we developed a revised method, which can be put into the actual operation to improve the forecast accuracy and relative error of daily maximum (minimum) air temperature, using the T639 2 meter temperature numerical forecast products during 24 hours and the observations in 8 regional automatic stations in Jimo from January 2013 to December 2015 Based on the contrast verification, it is concluded that the comprehensive correction is the most accurate method among the seasonal correction, comprehensive correction, wind direction correction, and wind velocity correction, which is combined with wind direction and wind velocity forecast and terrain zoning.
2017, 45(6):1070-1076.
Abstract:
Based on the conventional observational data, wind profile data and NCEP / NCAR1°×1° reanalysis data, a strong wind process happened over the Yellow and Bohai Seas on 1 October 2015 is analyzed. Results show that the largescale baric gradient wind caused by the cold air and rapidly growing surface cyclone led to the gale.The strong cold advection area is corresponding to the ground allobaric wind. The whole layer cold advection caused the strong pressure gradient and allobaric gradient on the ground. Pressure gradient played a leading role in the early wind process, and allobaric gradient was conducive to the maintenance of strong winds and downward propagation of upper level momentum occurred in this process; the lower level winds at 500 to 1000 meters affected the surface wind, and the wind above 2000 meters affected the surface wind after the trough crossing. The wind profile observations of lowlevel strong winds accompanied by strong subsidence movement can be used as an indicator of high sea wind warning.
Based on the conventional observational data, wind profile data and NCEP / NCAR1°×1° reanalysis data, a strong wind process happened over the Yellow and Bohai Seas on 1 October 2015 is analyzed. Results show that the largescale baric gradient wind caused by the cold air and rapidly growing surface cyclone led to the gale.The strong cold advection area is corresponding to the ground allobaric wind. The whole layer cold advection caused the strong pressure gradient and allobaric gradient on the ground. Pressure gradient played a leading role in the early wind process, and allobaric gradient was conducive to the maintenance of strong winds and downward propagation of upper level momentum occurred in this process; the lower level winds at 500 to 1000 meters affected the surface wind, and the wind above 2000 meters affected the surface wind after the trough crossing. The wind profile observations of lowlevel strong winds accompanied by strong subsidence movement can be used as an indicator of high sea wind warning.
2017, 45(6):1077-1082.
Abstract:
Aiming at solving the problem of urban waterlog in Handan, Hebei Province, this study established an application model based on the twodimensional information diffusion technology and natural disaster risk assessing theory, collected the original data, including the location and waterlog history, raining intensity, danger sources and risk bearing objects of waterlogging spots which needs the supports of meteorology department, municipal drainage department and social communities. Then the assessment model is constructed, which includes the indexes of raining intensity, waterlog depth of the waterlog spots and their probably risk scenarios. The model can make the waterlog depth prediction for a certain waterlog spot with a certain raining strength input, and then can estimate the risk scenarios for each of the risk bearing objects near the spot. The study shows that the urban road waterlog risk evaluation model has a certain practical value for urban waterlog problems in plain cities.
Aiming at solving the problem of urban waterlog in Handan, Hebei Province, this study established an application model based on the twodimensional information diffusion technology and natural disaster risk assessing theory, collected the original data, including the location and waterlog history, raining intensity, danger sources and risk bearing objects of waterlogging spots which needs the supports of meteorology department, municipal drainage department and social communities. Then the assessment model is constructed, which includes the indexes of raining intensity, waterlog depth of the waterlog spots and their probably risk scenarios. The model can make the waterlog depth prediction for a certain waterlog spot with a certain raining strength input, and then can estimate the risk scenarios for each of the risk bearing objects near the spot. The study shows that the urban road waterlog risk evaluation model has a certain practical value for urban waterlog problems in plain cities.
21 Variation of Atmospheric Composition in UTLS during a Strong Convection Process in Tibetan Plateau
2017, 45(6):1083-1089.
Abstract:
The Tibetan Plateau is an important channel of water vapor and pollutants from troposphere into stratosphere, and these atmospheric constituents have important impact on the global climate. By using MLS and ERAInterim data, the distribution of atmospheric composition, including H2O, O3, CO, and IWC during a strong convective weather process occurring in the central Tibetan Plateau is analyzed. With the Wei formula to estimate the H2O and O3 flux crossing tropopause. Results indicate: (1) O3 mixing ratio increased from 03×10-6(V) ppmv to 09×10-6(V) at 100 hPa compared with the average; CO increased 08×10-6(V) below 150 hPa; H2O by 80 ppmv at 215 hPa and IWC significantly increased more than double to 0027 g/m3 (2) Before the convective activity began, the upward movement gradually strengthened, and total O3 and H2O flux were contributed by the vertical instantaneous movement. Thus the lifting effect of the strong convection to the atmosphere in UTLS (Upper Troposphere and Lower Stratosphere) made atmospheric composition change accordingly over the Tibetan Plateau.
The Tibetan Plateau is an important channel of water vapor and pollutants from troposphere into stratosphere, and these atmospheric constituents have important impact on the global climate. By using MLS and ERAInterim data, the distribution of atmospheric composition, including H2O, O3, CO, and IWC during a strong convective weather process occurring in the central Tibetan Plateau is analyzed. With the Wei formula to estimate the H2O and O3 flux crossing tropopause. Results indicate: (1) O3 mixing ratio increased from 03×10-6(V) ppmv to 09×10-6(V) at 100 hPa compared with the average; CO increased 08×10-6(V) below 150 hPa; H2O by 80 ppmv at 215 hPa and IWC significantly increased more than double to 0027 g/m3 (2) Before the convective activity began, the upward movement gradually strengthened, and total O3 and H2O flux were contributed by the vertical instantaneous movement. Thus the lifting effect of the strong convection to the atmosphere in UTLS (Upper Troposphere and Lower Stratosphere) made atmospheric composition change accordingly over the Tibetan Plateau.
2017, 45(6):1090-1094.
Abstract:
By using the daily power load data and meteorological data from June to August from 2010 to 2012, the variations of daily maximum load in muggy weather and sunny hot weather are analyzed. The results show that there were 4 sunny hot processes occurred in June, 5 muggy processes occurred in July and August during the 3 years in Xi’an, and the power load growth was more obvious in muggy processes. Tracking the change of meteorological power load with the daily maximum temperature, when daily maximum temperature reached 33 ℃, the meteorological power load increase rapidly, and the daily maximum temperature of 33 ℃, 35 ℃ and 38 ℃ are three sensitive points of meteorological power load to air temperature variations in Xi’an. Considering the accumulated temperature effect as a forecast factor and using the multiple regression method, a forecasting model for meteorological power load in summer in Xi’an is established. Using the historic data in summer of 2013, the application test shows that the mean relative predicting error of the daily maximum load is 60%。The proposed model can be a good simulation of the actual changes in meteorological power load and provide some guidance for the power supply meteorological service of Xi’an in summer.
By using the daily power load data and meteorological data from June to August from 2010 to 2012, the variations of daily maximum load in muggy weather and sunny hot weather are analyzed. The results show that there were 4 sunny hot processes occurred in June, 5 muggy processes occurred in July and August during the 3 years in Xi’an, and the power load growth was more obvious in muggy processes. Tracking the change of meteorological power load with the daily maximum temperature, when daily maximum temperature reached 33 ℃, the meteorological power load increase rapidly, and the daily maximum temperature of 33 ℃, 35 ℃ and 38 ℃ are three sensitive points of meteorological power load to air temperature variations in Xi’an. Considering the accumulated temperature effect as a forecast factor and using the multiple regression method, a forecasting model for meteorological power load in summer in Xi’an is established. Using the historic data in summer of 2013, the application test shows that the mean relative predicting error of the daily maximum load is 60%。The proposed model can be a good simulation of the actual changes in meteorological power load and provide some guidance for the power supply meteorological service of Xi’an in summer.
2017, 45(6):1095-1098.
Abstract:
In the history of the Yellow River in Ningxia, there had been floodplain and even flooded fields, which brought about serious losses. Most of these disasters occurred in the process of freezing and melting, and the ice floe density is one of the important indicators. Based on the meteorological and hydrological data of the Ningxia section of the Yellow River in Ningxia from 2008 to 2015, the paper carries out the simulation of the ice floe density and the meteorological elements 3 to 7 days before the ice floe occurred by means of the multiple/linear regression methods. The results show that the model is reliable, and the meteorological elements can be used to calculate the ice floe density. It is possible to make the ice floe density prediction of Yellow River based on numerical weather prediction.
In the history of the Yellow River in Ningxia, there had been floodplain and even flooded fields, which brought about serious losses. Most of these disasters occurred in the process of freezing and melting, and the ice floe density is one of the important indicators. Based on the meteorological and hydrological data of the Ningxia section of the Yellow River in Ningxia from 2008 to 2015, the paper carries out the simulation of the ice floe density and the meteorological elements 3 to 7 days before the ice floe occurred by means of the multiple/linear regression methods. The results show that the model is reliable, and the meteorological elements can be used to calculate the ice floe density. It is possible to make the ice floe density prediction of Yellow River based on numerical weather prediction.
2017, 45(6):1099-1105.
Abstract:
According to the troubleshooting requirements of FY3 meteorological satellites data acquisition in domestic and oversea ground stations, a remote fault diagnosis system is developed by means of Java 16 in the Eclipse 36 platform. The general framework is analyzed, and the workflow is introduced. The system can realize the remote and centralized monitoring of equipment running status in ground stations, trigger automatic fault diagnosis and rulebased fault diagnosis by parsing the quality logs, generate trouble tickets and import the expert experience database, and provide text and graphics query methods. Through the practical verification, it is proved that the system can assist knowledge engineers in remote, precise and rapid fault location with a friendly graphical user interface, boost the fault diagnosis efficiency, and enhance the remote monitoring capability of the integrity operating control system. The system has a certain practical significance to improve the quality of FY3 meteorological satellites data acquisition.
According to the troubleshooting requirements of FY3 meteorological satellites data acquisition in domestic and oversea ground stations, a remote fault diagnosis system is developed by means of Java 16 in the Eclipse 36 platform. The general framework is analyzed, and the workflow is introduced. The system can realize the remote and centralized monitoring of equipment running status in ground stations, trigger automatic fault diagnosis and rulebased fault diagnosis by parsing the quality logs, generate trouble tickets and import the expert experience database, and provide text and graphics query methods. Through the practical verification, it is proved that the system can assist knowledge engineers in remote, precise and rapid fault location with a friendly graphical user interface, boost the fault diagnosis efficiency, and enhance the remote monitoring capability of the integrity operating control system. The system has a certain practical significance to improve the quality of FY3 meteorological satellites data acquisition.
2017, 45(6):1106-1111.
Abstract:
The automatic weather station is a realtime surface meteorological observation system, it is important to locate the fault quickly and recovery in time when the automatic weather station fails. But it often takes a long time to find the fault, because of the lack of a certain detection equipment. In this paper, a portable detector is designed for automatic weather stations, which can quickly detect the faults of temperature, humidity, rainfall, wind direction, wind speed, pressure, visibility, evaporation sensors, fiber, and cable. Users can directly check the current observation data and operating status of the automatic weather station on the instruments LCD screen. The detector can locate the fault point quickly in the automatic weather station observation system, shorten the recovery time, improve the maintenance capabilities of the technical staff, and has a high potential in application.
The automatic weather station is a realtime surface meteorological observation system, it is important to locate the fault quickly and recovery in time when the automatic weather station fails. But it often takes a long time to find the fault, because of the lack of a certain detection equipment. In this paper, a portable detector is designed for automatic weather stations, which can quickly detect the faults of temperature, humidity, rainfall, wind direction, wind speed, pressure, visibility, evaporation sensors, fiber, and cable. Users can directly check the current observation data and operating status of the automatic weather station on the instruments LCD screen. The detector can locate the fault point quickly in the automatic weather station observation system, shorten the recovery time, improve the maintenance capabilities of the technical staff, and has a high potential in application.
2017, 45(6):1112-1115.
Abstract:
A newtype integrated technology of weather radar transmitter burst detection is designed,which highly integrated CNC attenuator, envelope detector, A/D converter and FPGA (Field Programmable Gate Array) processor. The system can detect the transmitter pulse characteristics quickly and accurately without other instruments and tools to assist, conduct automatic testing and automatic test report generating, and based on the test results give maintenance recommendations, effectively solve the problem of station weather radar on the launch pulse envelope of the traditional test and maintenance, and effectively reduce the human errors, to recluce the constraints and impact of the station weather radar fault diagnosis and routine maintenance, to promote the standardization and automation of weather radar testing, service, and maintenance.
A newtype integrated technology of weather radar transmitter burst detection is designed,which highly integrated CNC attenuator, envelope detector, A/D converter and FPGA (Field Programmable Gate Array) processor. The system can detect the transmitter pulse characteristics quickly and accurately without other instruments and tools to assist, conduct automatic testing and automatic test report generating, and based on the test results give maintenance recommendations, effectively solve the problem of station weather radar on the launch pulse envelope of the traditional test and maintenance, and effectively reduce the human errors, to recluce the constraints and impact of the station weather radar fault diagnosis and routine maintenance, to promote the standardization and automation of weather radar testing, service, and maintenance.
2017, 45(6):1116-1124.
Abstract:
Data quality assessment is an important part in model operation application. In this paper, the soil moisture observation data and China Meteorological Administration Land Data Assimilation System (CLDAS) data are used to establish the online CLDAS data quality assessment system through the MySQL database and the Web technology like html, JavaScript, HighChart， etc. The assessment analysis between the simulated soil moisture and the observed soil moisture at any of stations and provinces, times and different soil layers is implemented in the form of correlation coefficient, root mean square error, relative deviation, and mean deviation. Diagrams such as time series and scatter are visually displayed to compare the observation and simulated data in the system. The statistical indexes can be calculated immediately using JavaScript language in the Web platform. The assessment results and the comparison diagrams can be showed through the internet Web page, and the realtime monitoring of the model product data quality can be achieved.
Data quality assessment is an important part in model operation application. In this paper, the soil moisture observation data and China Meteorological Administration Land Data Assimilation System (CLDAS) data are used to establish the online CLDAS data quality assessment system through the MySQL database and the Web technology like html, JavaScript, HighChart， etc. The assessment analysis between the simulated soil moisture and the observed soil moisture at any of stations and provinces, times and different soil layers is implemented in the form of correlation coefficient, root mean square error, relative deviation, and mean deviation. Diagrams such as time series and scatter are visually displayed to compare the observation and simulated data in the system. The statistical indexes can be calculated immediately using JavaScript language in the Web platform. The assessment results and the comparison diagrams can be showed through the internet Web page, and the realtime monitoring of the model product data quality can be achieved.
2017, 45(6):1125-1128.
Abstract:
The lightning has the features of sudden, instance and threedimensionality. These features lead to the limitation of instant processing and display of the thunder monitoring data based on the Web end, and the lightning nowcasting in the small range has been influenced. Therefore, the visualization of lightning data based on the Android mobility device by means of the GPS location technology has great significance. In combination with the realtime monitoring data of thunders and lightning and the GPS location data, assembling the logic processes like the collection, transformation, integration and data superimposing, remarking the information like the location, intensity and the occurrence distance of thunder, and displaying accurately on the mobile device map through the method of adding the cover intuitively, the lightning situation can be shown in real time within 20 km around the user. The users can take the corresponding precautions in time in order to reduce the life and fortune loss caused by thunder disasters.
The lightning has the features of sudden, instance and threedimensionality. These features lead to the limitation of instant processing and display of the thunder monitoring data based on the Web end, and the lightning nowcasting in the small range has been influenced. Therefore, the visualization of lightning data based on the Android mobility device by means of the GPS location technology has great significance. In combination with the realtime monitoring data of thunders and lightning and the GPS location data, assembling the logic processes like the collection, transformation, integration and data superimposing, remarking the information like the location, intensity and the occurrence distance of thunder, and displaying accurately on the mobile device map through the method of adding the cover intuitively, the lightning situation can be shown in real time within 20 km around the user. The users can take the corresponding precautions in time in order to reduce the life and fortune loss caused by thunder disasters.
2017, 45(6):1129-1135.
Abstract:
With the rapid development of information technology and the rapid advance of meteorological modernization, the public demands for meteorological services are getting higher and higher. Meanwhile, the types and quality of meteorological service products also need to keep pace with the times. Starting from the actual needs of users, this article studies the service phrase algorithm and application of 0 to 1 hour precipitation forecast, which is based on the data fusion of radar inversion, focusing on the implementation of 0 to 1 hour precipitation forecast algorithm design and the algorithm logic of service phrase generation under different precipitation trends. On the basis of the research results, the 0 to 1 hour precipitation forecast service phrase application system is developed, which has been integrated into the smart meteorological APP and the Zhejiang precipitation distribution system client software to carry out mobile services. It not only opens up a new model of networking weather service and helps to improve the quality of meteorological service, but also lays a foundation for the future researches and application of various kinds of meteorological service phrases.
With the rapid development of information technology and the rapid advance of meteorological modernization, the public demands for meteorological services are getting higher and higher. Meanwhile, the types and quality of meteorological service products also need to keep pace with the times. Starting from the actual needs of users, this article studies the service phrase algorithm and application of 0 to 1 hour precipitation forecast, which is based on the data fusion of radar inversion, focusing on the implementation of 0 to 1 hour precipitation forecast algorithm design and the algorithm logic of service phrase generation under different precipitation trends. On the basis of the research results, the 0 to 1 hour precipitation forecast service phrase application system is developed, which has been integrated into the smart meteorological APP and the Zhejiang precipitation distribution system client software to carry out mobile services. It not only opens up a new model of networking weather service and helps to improve the quality of meteorological service, but also lays a foundation for the future researches and application of various kinds of meteorological service phrases.
2017, 45(6):1136-1140.
Abstract:
From the consumption assessment for detecting radar spare parts of the CMA Meteorological Observation Center from 2006 to 2015 and the fault cases acquired from nationwide CINRAD/SA radar stations from 2007 to 2015 by the project team, it is found that the transmitter failure rate is second only to the servo system, which is closely related to the highvoltage work environment for a long time, seriously affecting the observation, being very difficult to deal with. This paper summarizes the methods to solve the highvoltage faults by gathering the maintenance experiences from the nationwide CINRAD/SA radar stations, binding the parameter characteristics of the related components and analyzing common highvoltage faults. Two typical highvoltage fault cases are studied to provide reference for stations.
From the consumption assessment for detecting radar spare parts of the CMA Meteorological Observation Center from 2006 to 2015 and the fault cases acquired from nationwide CINRAD/SA radar stations from 2007 to 2015 by the project team, it is found that the transmitter failure rate is second only to the servo system, which is closely related to the highvoltage work environment for a long time, seriously affecting the observation, being very difficult to deal with. This paper summarizes the methods to solve the highvoltage faults by gathering the maintenance experiences from the nationwide CINRAD/SA radar stations, binding the parameter characteristics of the related components and analyzing common highvoltage faults. Two typical highvoltage fault cases are studied to provide reference for stations.
2017, 45(6):1141-1145.
Abstract:
The weighing gauges have been widely used nationwide in ground observing stations, undertaking the observation task of winter precipitation and providing observation data for winter precipitation forecast and service. Currently, 126 sets of weighing gauges have been put to use by the Beijing Meteorological Service, of which 90% are DSC2 weighing gauges. This paper focuses on the introduction of basic principles and the data quality control algorithm of DSC2 weighing gauges, and then two kinds of typical common faults are analyzed to propose the corresponding judgment methods and solutions. Finally, several precautions of daily maintenance for DSC2 weighing gauges are put forward to reduce related equipment failures.
The weighing gauges have been widely used nationwide in ground observing stations, undertaking the observation task of winter precipitation and providing observation data for winter precipitation forecast and service. Currently, 126 sets of weighing gauges have been put to use by the Beijing Meteorological Service, of which 90% are DSC2 weighing gauges. This paper focuses on the introduction of basic principles and the data quality control algorithm of DSC2 weighing gauges, and then two kinds of typical common faults are analyzed to propose the corresponding judgment methods and solutions. Finally, several precautions of daily maintenance for DSC2 weighing gauges are put forward to reduce related equipment failures.
External LinksChina Meteorological AdministrationCMA Meteorological Observation CentreChinese Academy of Meteorological SciencesBeijing Meteorological ServiceNational Satellite Meteorological Center
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Supported by:Beijing E-Tiller Technology Development Co., Ltd.
Supported by:Beijing E-Tiller Technology Development Co., Ltd.