Volume 32,Issue 4,2004 Table of Contents
2004, 32(4):201-205.
Abstract:
GPS meteorology has been become a frontier research field and intercrossed subject since 1990's, and the remote sensing of atmospheric water vapor using GPS also has made obvious progress. This new technique will play an important role in researches on atmospheric sounding, weather forecasting and climatic change, as well as on operational applications. The significance of remote sensing of regional atmospheric water vapor by GPS in meteorology is discussed and the peculiarity and superiority of GPS technique are compared with other sounding methods. The methods and principles of remote sensing of regional atmospheric water vapor by ground-based GPS are introduced, and the present situation and prospects in the remote sensing of potential water vapor in recent 10 years by using the regional ground-based GPS network at home and abroad are analyzed. Some major problems need to be solved in this field are pointed out.
GPS meteorology has been become a frontier research field and intercrossed subject since 1990's, and the remote sensing of atmospheric water vapor using GPS also has made obvious progress. This new technique will play an important role in researches on atmospheric sounding, weather forecasting and climatic change, as well as on operational applications. The significance of remote sensing of regional atmospheric water vapor by GPS in meteorology is discussed and the peculiarity and superiority of GPS technique are compared with other sounding methods. The methods and principles of remote sensing of regional atmospheric water vapor by ground-based GPS are introduced, and the present situation and prospects in the remote sensing of potential water vapor in recent 10 years by using the regional ground-based GPS network at home and abroad are analyzed. Some major problems need to be solved in this field are pointed out.
2004, 32(4):206-212.
Abstract:
The meaning of quantitative precipitation is discussed. The instruments aboard Tropical Rainfall Measurement Mission (TRMM) and the products of the TRMM Microwave Imager from National Aeronautics and Space Administration are described. The principles of microwave precipitation retrieval, the comparison of physical methods and empirical methods are narrated, and some empirical algorithms are introduced and discussions are made on the effect of the tilted convective system on upwelling microwave brightness temperature, the clustering analysis algorithms and the neural network algorithms.
The meaning of quantitative precipitation is discussed. The instruments aboard Tropical Rainfall Measurement Mission (TRMM) and the products of the TRMM Microwave Imager from National Aeronautics and Space Administration are described. The principles of microwave precipitation retrieval, the comparison of physical methods and empirical methods are narrated, and some empirical algorithms are introduced and discussions are made on the effect of the tilted convective system on upwelling microwave brightness temperature, the clustering analysis algorithms and the neural network algorithms.
2004, 32(4):213-218.
Abstract:
The developing history of meteorological observation on commercial aircrafts is reviewed and its characteristics and applications to weather operation and atmospheric researches are described. The acquisition approaches, advantages and limitations of the observation data from commercial aircrafts are analyzed and its future trend is given. It is pointed out that meteorological observation on commercial aircrafts, as an important observation platform, has broad prospects in application and has attracted great attention of meteorological service and civil aviation industry. The data from the commercial aircraft observation will further improve the accuracy of weather forecasts and promote the weather service level, especially improving the performance of NWP models, and it will certainly play a more and more important role in meteorological researches and operational weather forecasting.
The developing history of meteorological observation on commercial aircrafts is reviewed and its characteristics and applications to weather operation and atmospheric researches are described. The acquisition approaches, advantages and limitations of the observation data from commercial aircrafts are analyzed and its future trend is given. It is pointed out that meteorological observation on commercial aircrafts, as an important observation platform, has broad prospects in application and has attracted great attention of meteorological service and civil aviation industry. The data from the commercial aircraft observation will further improve the accuracy of weather forecasts and promote the weather service level, especially improving the performance of NWP models, and it will certainly play a more and more important role in meteorological researches and operational weather forecasting.
2004, 32(4):219-224.
Abstract:
Micro-Pulse Lidar (MPL) systems provide continuous, automatic observation of nearly all significant atmospheric clouds and aerosols. Being compact in structure and with eye-safe transmitted radiation, the systems proved reliable in a number of experiments both at home and abroad (such as ACE-2 and Aerosols99). An introduction to the structures and working principles of MPL systems, as well as their advantages over traditional ones, are given. The retrieval methods of lidar-determined aerosol optical properties (such as slope, near-end, far-end and iteration methods) and their advantages and disadvantages,and a summary of application researches of MPL to ABL and aerosol measurement, etc., are presented.
Micro-Pulse Lidar (MPL) systems provide continuous, automatic observation of nearly all significant atmospheric clouds and aerosols. Being compact in structure and with eye-safe transmitted radiation, the systems proved reliable in a number of experiments both at home and abroad (such as ACE-2 and Aerosols99). An introduction to the structures and working principles of MPL systems, as well as their advantages over traditional ones, are given. The retrieval methods of lidar-determined aerosol optical properties (such as slope, near-end, far-end and iteration methods) and their advantages and disadvantages,and a summary of application researches of MPL to ABL and aerosol measurement, etc., are presented.
5 Remote Sensing of Atmospheric Water Vapor Characteristics in Anhui Province Using Ground-Based GPS
2004, 32(4):225-228.
Abstract:
Using GPS data from six sites in Feixi, Tongcheng, Shouxian, Wuwei, Wuhu, and Chuzhou from June to July 2002, estimation was conducted on the continuous atmospheric precipitable water (PW) with a temporal resolution of 30 min. The temperature and air pressure data from above six sites were used. The accuracy of the deduced PW results is 1-2 mm, acquired by the analytical method, sufficient for weather forecasting and climate researches. The characteristics of water vapor in theses areas were analyzed by means of the results. The durative accumulation and continuous transport of water vapor are the necessary conditions of formation and development of severe storms. In order to better understand where vapor come from and what is the vapor amount, the water vapor flux was estimated in combination with NCEP data during a severe storm case.
Using GPS data from six sites in Feixi, Tongcheng, Shouxian, Wuwei, Wuhu, and Chuzhou from June to July 2002, estimation was conducted on the continuous atmospheric precipitable water (PW) with a temporal resolution of 30 min. The temperature and air pressure data from above six sites were used. The accuracy of the deduced PW results is 1-2 mm, acquired by the analytical method, sufficient for weather forecasting and climate researches. The characteristics of water vapor in theses areas were analyzed by means of the results. The durative accumulation and continuous transport of water vapor are the necessary conditions of formation and development of severe storms. In order to better understand where vapor come from and what is the vapor amount, the water vapor flux was estimated in combination with NCEP data during a severe storm case.
2004, 32(4):229-232.
Abstract:
Near real-time (NRT) water vapor remote sensing by GPS is of great potential in weather forecasting and climate research. Availability and precision of the ephemeris are the key issues. The data from the 2000 Beijing GPS/VAPOR Experiment were processed by using the precisely predicted and final ephemeris files downloaded from IGS website, and GPS PWV (precipitable water vapor) was obtained. On the basis of the radiosonde water vapor, the PWV calculated from the predicted ephemeris shows a RMS of 0.31 cm, only 0.01 cm greater than that from the final. Therefore, the predicted ephemeris can meet the requirement of GPS NRT water vapor remote sensing.
Near real-time (NRT) water vapor remote sensing by GPS is of great potential in weather forecasting and climate research. Availability and precision of the ephemeris are the key issues. The data from the 2000 Beijing GPS/VAPOR Experiment were processed by using the precisely predicted and final ephemeris files downloaded from IGS website, and GPS PWV (precipitable water vapor) was obtained. On the basis of the radiosonde water vapor, the PWV calculated from the predicted ephemeris shows a RMS of 0.31 cm, only 0.01 cm greater than that from the final. Therefore, the predicted ephemeris can meet the requirement of GPS NRT water vapor remote sensing.
2004, 32(4):233-236.
Abstract:
The 3D visualization of remote sensing images was realized by means of DEM data, which greatly improved the application of remote sensing products; however, those commercial software are costly,inconvenient to use and difficult to popularize, so a program of 3D remote sensing image visualization was developed by using the Delphi programming language based on computer graphical principles. The solutions and realizing methods for problems encountered in practice are introduced, such as cutting and the join-together of DEM data, image matching, earth surface simulation, perspective counterchange, black-out processing, effects of illumination and shadow, color change, etc.
The 3D visualization of remote sensing images was realized by means of DEM data, which greatly improved the application of remote sensing products; however, those commercial software are costly,inconvenient to use and difficult to popularize, so a program of 3D remote sensing image visualization was developed by using the Delphi programming language based on computer graphical principles. The solutions and realizing methods for problems encountered in practice are introduced, such as cutting and the join-together of DEM data, image matching, earth surface simulation, perspective counterchange, black-out processing, effects of illumination and shadow, color change, etc.
2004, 32(4):237.
Abstract:
The integrated mosaic technique of new generation Doppler weather redar network was applied in the CHeRES experiment.The technique includes the processing and conversion of radar volume scanning data,the uniform processing of radar network data,the strategy to make radar data mosaics for different bands,the wind field retrieving and the composite result display.Also based on this technique,the application software system was developed,which was used for the ovlume scanning data obtained from vari-type radars in the CHeRES experiment in 2001 and 2002,and some data mosaic results are given.
The integrated mosaic technique of new generation Doppler weather redar network was applied in the CHeRES experiment.The technique includes the processing and conversion of radar volume scanning data,the uniform processing of radar network data,the strategy to make radar data mosaics for different bands,the wind field retrieving and the composite result display.Also based on this technique,the application software system was developed,which was used for the ovlume scanning data obtained from vari-type radars in the CHeRES experiment in 2001 and 2002,and some data mosaic results are given.
2004, 32(4):242-246.
Abstract:
A description is made of the technical analyzing process of radar tower and frequency-point height determination during the construction of the Wuhan CINRAD/SA Radar System. The requirements for protection of bare space around the radar station are pointed out clearly. The spatial power density distributions of electromagnetic radiation of the CINRAD/SA Radar in three operating modes (VCP11, VCP21 and VCP31) are calculated and analyzed and the minimum protection distance is estimated according to the Regulations for Electromagnetic Radiation Protection and Environmental Impact Assessment Methods and Standards on Electromagnetic Radiation.
A description is made of the technical analyzing process of radar tower and frequency-point height determination during the construction of the Wuhan CINRAD/SA Radar System. The requirements for protection of bare space around the radar station are pointed out clearly. The spatial power density distributions of electromagnetic radiation of the CINRAD/SA Radar in three operating modes (VCP11, VCP21 and VCP31) are calculated and analyzed and the minimum protection distance is estimated according to the Regulations for Electromagnetic Radiation Protection and Environmental Impact Assessment Methods and Standards on Electromagnetic Radiation.
2004, 32(4):247.
Abstract:
In order to improve operation scientifically,new-type Doppler radar and SSS (RS, GIS, GPS) technology are used in rain enhancement to command the rocket vehicle in real time and flexibly. Based on the analysis of local weather characteristics, radar echo features and the up-to-date technology, discussed are some crucial issues relevant to the utilization of Doppler radar in cloud seeding such as the choice of target clouds, the estimation of catalyzing potential, identification of catalyzing opportunity and the determination of catalyziong points, etc. An new technical operation method is presented, including rocket monitoring, index identification, operational parameter formation and effectiveness feedback, etc., and a technical procedure was proposed, in which SSS technology was adopted to trace and control operation vehicles in real time and scientifically.
In order to improve operation scientifically,new-type Doppler radar and SSS (RS, GIS, GPS) technology are used in rain enhancement to command the rocket vehicle in real time and flexibly. Based on the analysis of local weather characteristics, radar echo features and the up-to-date technology, discussed are some crucial issues relevant to the utilization of Doppler radar in cloud seeding such as the choice of target clouds, the estimation of catalyzing potential, identification of catalyzing opportunity and the determination of catalyziong points, etc. An new technical operation method is presented, including rocket monitoring, index identification, operational parameter formation and effectiveness feedback, etc., and a technical procedure was proposed, in which SSS technology was adopted to trace and control operation vehicles in real time and scientifically.
2004, 32(4):251.
Abstract:
CINRAD/SA, China Next Generation Weather Radar,was produced by the Beijing METSATAR Radar Co., Ltd, based on the NEXRAD WSR-88D technology.Its software system was modified to provide the new RHI/PPI scan mode because NEXRAD WSR-88D provides only the volume scan mode. The design and realization of the RHI/PPI scan mode on the CINRAD/SA are described.
CINRAD/SA, China Next Generation Weather Radar,was produced by the Beijing METSATAR Radar Co., Ltd, based on the NEXRAD WSR-88D technology.Its software system was modified to provide the new RHI/PPI scan mode because NEXRAD WSR-88D provides only the volume scan mode. The design and realization of the RHI/PPI scan mode on the CINRAD/SA are described.
2004, 32(4):255.
Abstract:
The characteristics and capabilities, meteorological application products and their software of the currently networking radars in China are described and examples of hail cloud identifying and tracking, mesoscale cyclones and heavy rainfall are presented. The New-Generation Weather Radar Network of China has the considerable capabilities in monitoring and warning severe weather, in estimating quantitatively large-scale precipitation (typhoon), and in deriving wind-field messages from echo signals. It is a comprehensive intelligent system with the capabilities of sounding, analyzing, predicting and warning combined.
The characteristics and capabilities, meteorological application products and their software of the currently networking radars in China are described and examples of hail cloud identifying and tracking, mesoscale cyclones and heavy rainfall are presented. The New-Generation Weather Radar Network of China has the considerable capabilities in monitoring and warning severe weather, in estimating quantitatively large-scale precipitation (typhoon), and in deriving wind-field messages from echo signals. It is a comprehensive intelligent system with the capabilities of sounding, analyzing, predicting and warning combined.
2004, 32(4):258-262.
Abstract:
Integrating nephelometers were installed at each station of the dust storm monitoring net by the China Meteorological Administration. This is the first time that the optical porperties of aerosol were monitored using integrating nephelometers on a large scale in China. The variation feature of scattering coefficient and the relation between scattering coefficient and PM10 mass concentration and visibility were analyzed based on the primary principles of integrating nephelometers,using the scattering coefficient data and PM10 mass concentration from Beijing Observatory and meteorological data from September to November 2003.The results indicate that the mean value (standard deviation) is 306 2 Mm -1(292 78 Mm -1).Wind speed has an important effect on scattering coefficient,while scattering coefficient has good correlation with PM10 mass concentration ( r = -0 761),and there exists a negative correlation between scattering and visibility ( r = -0 716).
Integrating nephelometers were installed at each station of the dust storm monitoring net by the China Meteorological Administration. This is the first time that the optical porperties of aerosol were monitored using integrating nephelometers on a large scale in China. The variation feature of scattering coefficient and the relation between scattering coefficient and PM10 mass concentration and visibility were analyzed based on the primary principles of integrating nephelometers,using the scattering coefficient data and PM10 mass concentration from Beijing Observatory and meteorological data from September to November 2003.The results indicate that the mean value (standard deviation) is 306 2 Mm -1(292 78 Mm -1).Wind speed has an important effect on scattering coefficient,while scattering coefficient has good correlation with PM10 mass concentration ( r = -0 761),and there exists a negative correlation between scattering and visibility ( r = -0 716).
2004, 32(4):263-268.
Abstract:
The work principles of the atmosphere profile synthesis detecting system (the wind profiler and RASS radar) are introduced. The application of the detecting technology in the upper air abroad is discussed by giving some examples. The system can be used to calculate humidity profiles, detect heat and dynamical structures of fronts and vertical wind structure, and diagnose the planetary boundary layer and rainfall cloud systems in tropic regions. The methods are proposed for calculating humidity profiles in the range of 0.2 km to 2.2 km in altitude by means of the wind profile/RASS data from the Feixi observing experiment site in Anhui Province in Summer 2002.
The work principles of the atmosphere profile synthesis detecting system (the wind profiler and RASS radar) are introduced. The application of the detecting technology in the upper air abroad is discussed by giving some examples. The system can be used to calculate humidity profiles, detect heat and dynamical structures of fronts and vertical wind structure, and diagnose the planetary boundary layer and rainfall cloud systems in tropic regions. The methods are proposed for calculating humidity profiles in the range of 0.2 km to 2.2 km in altitude by means of the wind profile/RASS data from the Feixi observing experiment site in Anhui Province in Summer 2002.
2004, 32(4):274-277.
Abstract:
An introduction is made to the frame, main properties of the Shaoxing Thunder and Lightning Positioning System and its development and application, based on the principles of the lightning mix-binding algorithm. The analysis results indicate that the system, as a complex sounding network with multiple functions (lighting detecting and positioning and data processing), is able to position lightning relatively correctly, and the sounding data can be used for a variety of applications. Through analyzing these data, it is possible to find out the formation and evolution regularities of thunders and lightning to make contributions to the forecasting and warning of thunder and lighting disasters.
An introduction is made to the frame, main properties of the Shaoxing Thunder and Lightning Positioning System and its development and application, based on the principles of the lightning mix-binding algorithm. The analysis results indicate that the system, as a complex sounding network with multiple functions (lighting detecting and positioning and data processing), is able to position lightning relatively correctly, and the sounding data can be used for a variety of applications. Through analyzing these data, it is possible to find out the formation and evolution regularities of thunders and lightning to make contributions to the forecasting and warning of thunder and lighting disasters.
2004, 32(4):278-280290.
Abstract:
The control and data processing system for four-channel microwave radiometers controlled by a single chip microprocessor is discussed. The system contains the interface circuit, data acquisition circuit, sequence control circuit and control and data processing module. The real-time multi-task operating system for the single chip microprocessor was designed. The software design contains task management, task communication, clock, input-output and interrupt management. The advanced digital modulation-demodulation technology for data managing methods was adopted. The system has capabilities of real-time control, data collection, real-time display and communication, etc., and has simple structure, small size, low cost and high reliability, thus has broad prospects in application.
The control and data processing system for four-channel microwave radiometers controlled by a single chip microprocessor is discussed. The system contains the interface circuit, data acquisition circuit, sequence control circuit and control and data processing module. The real-time multi-task operating system for the single chip microprocessor was designed. The software design contains task management, task communication, clock, input-output and interrupt management. The advanced digital modulation-demodulation technology for data managing methods was adopted. The system has capabilities of real-time control, data collection, real-time display and communication, etc., and has simple structure, small size, low cost and high reliability, thus has broad prospects in application.
2004, 32(4):281-285290.
Abstract:
A comparison was made using automatic weather station measurements and conventional observations from November 2002 to February 2003 (temperature, pressure, vapor-pressure, relative humidity and soil temperature of 5 cm to 320 cm in the winter of 2002. The results show that observational errors are relatively small for temperature, station-pressure, vapor-pressure, relative humidity, and soil temperature of 320 cm, and greater for soil temperatures of 5 cm to 160 cm. The chief reasons for observational errors include systematical errors, observational precision, and the sensitivity of the system's responding to changes of weather elements and observational time, as well as some artificial factors.
A comparison was made using automatic weather station measurements and conventional observations from November 2002 to February 2003 (temperature, pressure, vapor-pressure, relative humidity and soil temperature of 5 cm to 320 cm in the winter of 2002. The results show that observational errors are relatively small for temperature, station-pressure, vapor-pressure, relative humidity, and soil temperature of 320 cm, and greater for soil temperatures of 5 cm to 160 cm. The chief reasons for observational errors include systematical errors, observational precision, and the sensitivity of the system's responding to changes of weather elements and observational time, as well as some artificial factors.
2004, 32(4):286-290.
Abstract:
The field tests of WT-1 Fog Detectors are described and the acquired data during the tests are analyzed statistically. The absent rate of observation data from the WT-1 and FD12P, the correlation coefficients of WT-1 with visual observation and FD12P, the conformability of the three measurements and the variation trend of the difference with time are calculated. Based on the analysis results, the advantages and disadvantages of the detector are discussed. In comparison with Vaisala's visibility sensor FD12P, the difference between WT-1 Detector and FD12P is described, and improvement suggestions are proposed.
The field tests of WT-1 Fog Detectors are described and the acquired data during the tests are analyzed statistically. The absent rate of observation data from the WT-1 and FD12P, the correlation coefficients of WT-1 with visual observation and FD12P, the conformability of the three measurements and the variation trend of the difference with time are calculated. Based on the analysis results, the advantages and disadvantages of the detector are discussed. In comparison with Vaisala's visibility sensor FD12P, the difference between WT-1 Detector and FD12P is described, and improvement suggestions are proposed.
2004, 32(4):291-293302.
Abstract:
According to the performance specification requirements of the R97 International Recommendation and Verification Regulation for JJG 875-94 Digital Pressure Gauge for vibrating barometers, a complete performance test was conducted on vibrating barometers (model DQZ-1), which are widely used in conventional weather stations and aviation departments and other fields. The static performance test (repeatability, nonlinearity and hysteresis), thermal test, humidity test, short term stability test and long term stability test are described. The main factors causing measurement errors were identified through the study and analysis of experiment data. They are very useful for improving the accuracy of atmospheric pressure measurement.
According to the performance specification requirements of the R97 International Recommendation and Verification Regulation for JJG 875-94 Digital Pressure Gauge for vibrating barometers, a complete performance test was conducted on vibrating barometers (model DQZ-1), which are widely used in conventional weather stations and aviation departments and other fields. The static performance test (repeatability, nonlinearity and hysteresis), thermal test, humidity test, short term stability test and long term stability test are described. The main factors causing measurement errors were identified through the study and analysis of experiment data. They are very useful for improving the accuracy of atmospheric pressure measurement.
2004, 32(4):294-296.
Abstract:
The progress in hot-wire water content guage development is describedd briefly and discussions are made on the working principles and the display module of the KLWC-5 liquid water content guage and its application to microphysical sounding. The aircraft measurements can be used to improve the understanding of cloud microphysical structure, so to increase the effectiveness of rain enhancement.
The progress in hot-wire water content guage development is describedd briefly and discussions are made on the working principles and the display module of the KLWC-5 liquid water content guage and its application to microphysical sounding. The aircraft measurements can be used to improve the understanding of cloud microphysical structure, so to increase the effectiveness of rain enhancement.
2004, 32(4):297-299.
Abstract:
In order to solve the problems of data collection, real time display, data storage and automatic data processing, a research was conducted on the weather radar digital terminal and its applied software. The digital terminal improved the capability of weather radar in data saving and automatic data management. The applied software increases the efficiency of weather radar through adding several useful software products, such as hail warning, torrential rain warning, artificial precipitation effectiveness evaluation and so on.
In order to solve the problems of data collection, real time display, data storage and automatic data processing, a research was conducted on the weather radar digital terminal and its applied software. The digital terminal improved the capability of weather radar in data saving and automatic data management. The applied software increases the efficiency of weather radar through adding several useful software products, such as hail warning, torrential rain warning, artificial precipitation effectiveness evaluation and so on.
2004, 32(4):300-302.
Abstract:
The structure,operating principles,error sources for SL3 Rainfall Sensors are introduced.According to experiences,adjusting methods of measurement deviation and the routine maintenance for SL3 Rainfall Sensors are described in details.
The structure,operating principles,error sources for SL3 Rainfall Sensors are introduced.According to experiences,adjusting methods of measurement deviation and the routine maintenance for SL3 Rainfall Sensors are described in details.
2004, 32(4):303-304.
Abstract:
The existing problems for using sealed lead-acid batteries in Automatic Weather Stations (AWS) and the importance of charging method are analyzed. The basic principles of a modern fast charging method and its advantages in improving the using efficiency of sealed lead-acid batteries are discussed.
The existing problems for using sealed lead-acid batteries in Automatic Weather Stations (AWS) and the importance of charging method are analyzed. The basic principles of a modern fast charging method and its advantages in improving the using efficiency of sealed lead-acid batteries are discussed.
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.