Volume 40,Issue 6,2012 Table of Contents
2012, 40(6):869-873.
Abstract:
The differences of different band reflectance among water body, vegetation, urban area, soil and other objects are the foundation of extracting water body information by means of remote sensing data. Through analyzing the spectral characteristics of the water body information in remote sense images, the characteristics of MODIS image data and the methods for extracting water body information are introduced, and then the advantages and disadvantages of these methods and the effectiveness of the different water body indices are described in detail. The water body index is widely used to extract water body information. The results show that to apply different water body indices and spectral characteristics of MODIS data comprehensively can reduce substantially the influence of other different ground objects and extract water body information with a high precision, so to provide a quick and reliable basis for dynamic monitoring of water resources and water environment.
The differences of different band reflectance among water body, vegetation, urban area, soil and other objects are the foundation of extracting water body information by means of remote sensing data. Through analyzing the spectral characteristics of the water body information in remote sense images, the characteristics of MODIS image data and the methods for extracting water body information are introduced, and then the advantages and disadvantages of these methods and the effectiveness of the different water body indices are described in detail. The water body index is widely used to extract water body information. The results show that to apply different water body indices and spectral characteristics of MODIS data comprehensively can reduce substantially the influence of other different ground objects and extract water body information with a high precision, so to provide a quick and reliable basis for dynamic monitoring of water resources and water environment.
2012, 40(6):874-877.
Abstract:
The arctic is one of most climate sensitive areas in the world, but there is no enough polar meteorological observation data for a long time. In order to increase the weather forecast accuracy for Canada and North America, several departments of Canada, including the environment, meteorological, and defense departments, jointly launched a polar communication and meteorological satellite program (PCW: Polar Communication and Weather). The program will provide continuously communication and meteorological service and remote sensing observation for the region of over 50°N. The meteorological satellite will provide remote sensing information for the arctic region nearly every 15/30 minutes, with the emphases on the retrieval of wind fields for the high latitude region and the monitoring of sea/lake icing, snow cover, and vegetation, as well as the retrieval of clouds, aerosols, and volcanic ashes, which will play an important role in the researches on global climate changes. A brief introduction is made to the progress of the PCW program, the design, track balance, and remote sensing instruments of the satellite observation system, as well as the meteorological and space weather monitoring products and their applications.
The arctic is one of most climate sensitive areas in the world, but there is no enough polar meteorological observation data for a long time. In order to increase the weather forecast accuracy for Canada and North America, several departments of Canada, including the environment, meteorological, and defense departments, jointly launched a polar communication and meteorological satellite program (PCW: Polar Communication and Weather). The program will provide continuously communication and meteorological service and remote sensing observation for the region of over 50°N. The meteorological satellite will provide remote sensing information for the arctic region nearly every 15/30 minutes, with the emphases on the retrieval of wind fields for the high latitude region and the monitoring of sea/lake icing, snow cover, and vegetation, as well as the retrieval of clouds, aerosols, and volcanic ashes, which will play an important role in the researches on global climate changes. A brief introduction is made to the progress of the PCW program, the design, track balance, and remote sensing instruments of the satellite observation system, as well as the meteorological and space weather monitoring products and their applications.
2012, 40(6):878-884.
Abstract:
To ensure the accuracy of observation data, it is necessary to establish a comprehensive test system for radiation instruments, so as to test performance indexes. According to the provisions of WMO and ISO 9060, on the basis of verification regulations of pyranometers, experiments and researches have been conducted in zero offset, resolution, direction response, non linear error, and other performances indexes. Compared with thermal pyranometers, photoelectric pyranometers have significant spectral selectivity, and there are also other differences in spectral range, response time, measurement principles and structural materials. Therefore, their test methods are different. In the non linearity response test, the traditional solar simulator was replaced by the dual light superposition method. The study shows that it is advantageous to use the directional responses to indicate instrument’s performances in all directions and standardize the pyranometer’s classification than to use cosine errors and azimuth errors.
To ensure the accuracy of observation data, it is necessary to establish a comprehensive test system for radiation instruments, so as to test performance indexes. According to the provisions of WMO and ISO 9060, on the basis of verification regulations of pyranometers, experiments and researches have been conducted in zero offset, resolution, direction response, non linear error, and other performances indexes. Compared with thermal pyranometers, photoelectric pyranometers have significant spectral selectivity, and there are also other differences in spectral range, response time, measurement principles and structural materials. Therefore, their test methods are different. In the non linearity response test, the traditional solar simulator was replaced by the dual light superposition method. The study shows that it is advantageous to use the directional responses to indicate instrument’s performances in all directions and standardize the pyranometer’s classification than to use cosine errors and azimuth errors.
2012, 40(6):885-889.
Abstract:
A method of rainfall estimation by means of artificial neural network with the reflectivity, horizontal gradient and vertical integration of liquid water content is introduced, based on the radar data from the Hefei radar station in July 2007 and the Guangzhou radar station from May to October 2008 corresponding to the rain gauge data. The estimation of rainfall by the method is compared with the result of the 〖WTBX〗Z=300R1.4〖WTBZ〗 relationship. The results show that the rainfall estimation of the multi factor artificial neural network is better than that of the 〖WTBX〗Z=300R1.4〖WTBZ〗 relationship, according to the correlation coefficients and root mean square errors.
A method of rainfall estimation by means of artificial neural network with the reflectivity, horizontal gradient and vertical integration of liquid water content is introduced, based on the radar data from the Hefei radar station in July 2007 and the Guangzhou radar station from May to October 2008 corresponding to the rain gauge data. The estimation of rainfall by the method is compared with the result of the 〖WTBX〗Z=300R1.4〖WTBZ〗 relationship. The results show that the rainfall estimation of the multi factor artificial neural network is better than that of the 〖WTBX〗Z=300R1.4〖WTBZ〗 relationship, according to the correlation coefficients and root mean square errors.
2012, 40(6):890-895.
Abstract:
The servo system is mainly responsible for receiving radar terminal operator instructions and sending radar signals produced through the drive to control the antenna motion, and meanwhile receiving the instructions from the antennas’ rotating transformer, and sending the quantified information to the signal processing system. If the servo system cannot receive the antenna scanning movement instructions or cannot produce right signals to the driver, the antenna scan will stop. If the radar antenna scans regularly, but the angle data of antenna direction cannot be properly sent to the signal processing system, the linear or ring shaped graphics may be resulted at the radar terminal or a certain layer of scanning may miss in the processing. The causes of servo system failure are analyzed, and some suggestions about the servo system failure diagnosis and troubleshooting are given in combination with two cases of servo system failure, based on the flow, structure, and principles of servo system signals and the waveforms and parameters at key points. Various sorts of servo system failure are classified, aiming to eliminate servo system failure rapidly through accumulated experiences.
The servo system is mainly responsible for receiving radar terminal operator instructions and sending radar signals produced through the drive to control the antenna motion, and meanwhile receiving the instructions from the antennas’ rotating transformer, and sending the quantified information to the signal processing system. If the servo system cannot receive the antenna scanning movement instructions or cannot produce right signals to the driver, the antenna scan will stop. If the radar antenna scans regularly, but the angle data of antenna direction cannot be properly sent to the signal processing system, the linear or ring shaped graphics may be resulted at the radar terminal or a certain layer of scanning may miss in the processing. The causes of servo system failure are analyzed, and some suggestions about the servo system failure diagnosis and troubleshooting are given in combination with two cases of servo system failure, based on the flow, structure, and principles of servo system signals and the waveforms and parameters at key points. Various sorts of servo system failure are classified, aiming to eliminate servo system failure rapidly through accumulated experiences.
2012, 40(6):896-901.
Abstract:
Radar antenna is an important part of CINRAD/SA. For the complexity of its control process and the long running time, the failure rate of antennas is usually higher than the other parts of the radar subsystems. Taking a control sequences timeout failure of CINRAD/SA for an example, an analysis is made of the state and control information between the data acquisition unit (DAU) and the radar data acquisition processor (RDASC Processor) in depth, and the key hardware troubleshooting methods are summarized, for the purpose of the radar antenna maintenance, repair and technical support, so as to accumulate experiences for rapid troubleshooting.
Radar antenna is an important part of CINRAD/SA. For the complexity of its control process and the long running time, the failure rate of antennas is usually higher than the other parts of the radar subsystems. Taking a control sequences timeout failure of CINRAD/SA for an example, an analysis is made of the state and control information between the data acquisition unit (DAU) and the radar data acquisition processor (RDASC Processor) in depth, and the key hardware troubleshooting methods are summarized, for the purpose of the radar antenna maintenance, repair and technical support, so as to accumulate experiences for rapid troubleshooting.
2012, 40(6):902-905.
Abstract:
In order to safeguard the normal operation of radars and ensure that these expensive facilities could achieve expected benefits within the 20 years of the life cycle of CINRAD, a fault diagnosis system was developed, which includes the hardware test platform and corresponding software. The former requires the establishment of a complete performance test platform, and the latter requires the development of a fully functional test procedure, so as to quickly and accurately control the instruments, meters, and test equipment, and achieve the rapid analyzing, processing, storage, and display of test data. Through real tests, the reliability, availability, and operability of the system are discussed.
In order to safeguard the normal operation of radars and ensure that these expensive facilities could achieve expected benefits within the 20 years of the life cycle of CINRAD, a fault diagnosis system was developed, which includes the hardware test platform and corresponding software. The former requires the establishment of a complete performance test platform, and the latter requires the development of a fully functional test procedure, so as to quickly and accurately control the instruments, meters, and test equipment, and achieve the rapid analyzing, processing, storage, and display of test data. Through real tests, the reliability, availability, and operability of the system are discussed.
2012, 40(6):906-909.
Abstract:
Based on the experiment records of L band radiosonde sounding conducted at Nanjing Station in January 2009, taking the altitude data measured by GPS as the standards, the radiosonde height and radar altitude are analyzed in detail. It is concluded that the difference between radiosonde height and GPS altitude increases with the increasing height. The overall height difference tends to increase with height and the amplitude of the difference fluctuates dramatically. Below 100 hPa, the reliability of radiosonde height is greater than that of radar altitude, which is the best choice; however, above 100 hPa, the reliability of radar altitude is better, though the stability is poor.
Based on the experiment records of L band radiosonde sounding conducted at Nanjing Station in January 2009, taking the altitude data measured by GPS as the standards, the radiosonde height and radar altitude are analyzed in detail. It is concluded that the difference between radiosonde height and GPS altitude increases with the increasing height. The overall height difference tends to increase with height and the amplitude of the difference fluctuates dramatically. Below 100 hPa, the reliability of radiosonde height is greater than that of radar altitude, which is the best choice; however, above 100 hPa, the reliability of radar altitude is better, though the stability is poor.
2012, 40(6):910-913.
Abstract:
The influence of temperature and wind velocity on the dynamic characteristics of humidity sensors is studied by testing the dynamic characteristics under different temperatures and wind velocities according to the dynamic characteristics of humidity sensor calibration device. The time constants of a humidity sensor under different temperatures and wind velocities are calculated by using the graphic method, humidity changing method, and damp least square method, respectively. The results indicates that within the temperature range of 15 ℃ to 30 ℃, the time constants decrease with the rising temperature, and within the wind velocity range of 0 to 4 m/s, the time constants decrease with the increasing wind velocity. It is concluded that temperatures and wind velocities must be taken into account when evaluating dynamic characteristics of humidity sensor.
The influence of temperature and wind velocity on the dynamic characteristics of humidity sensors is studied by testing the dynamic characteristics under different temperatures and wind velocities according to the dynamic characteristics of humidity sensor calibration device. The time constants of a humidity sensor under different temperatures and wind velocities are calculated by using the graphic method, humidity changing method, and damp least square method, respectively. The results indicates that within the temperature range of 15 ℃ to 30 ℃, the time constants decrease with the rising temperature, and within the wind velocity range of 0 to 4 m/s, the time constants decrease with the increasing wind velocity. It is concluded that temperatures and wind velocities must be taken into account when evaluating dynamic characteristics of humidity sensor.
2012, 40(6):914-921.
Abstract:
Based on the RHtest method and the detailed metadata archive, the homogeneity of the monthly precipitation data from 1961 to 2009 of 1725 meteorological observation stations is examined and adjusted, taking Bomi, Yuanyang and Chaohu stations as examples. The results show that the homogeneity detection method works well for the examination of the precipitation data over China and has high prospects. It is more beneficial to the selection of the reference series to use 2400 stations monthly precipitation data, which has the higher density. Using both mathematical statistical analysis and subjective judgments with metadata is more reasonable to detect the homogeneity of the series. Only about 21 percent records are non homogeneous among the detected stations, which indicates that the homogeneity of the precipitation is good in most areas of China. For the non homogeneous stations, the change of location is one of the main causes. Applying the method of Rhtest, the series that have breakpoints are adjusted and the trends of the series are analyzed. It is found that the yearly precipitation trend has changed obviously and the homogeneity is improved well after adjustment.
Based on the RHtest method and the detailed metadata archive, the homogeneity of the monthly precipitation data from 1961 to 2009 of 1725 meteorological observation stations is examined and adjusted, taking Bomi, Yuanyang and Chaohu stations as examples. The results show that the homogeneity detection method works well for the examination of the precipitation data over China and has high prospects. It is more beneficial to the selection of the reference series to use 2400 stations monthly precipitation data, which has the higher density. Using both mathematical statistical analysis and subjective judgments with metadata is more reasonable to detect the homogeneity of the series. Only about 21 percent records are non homogeneous among the detected stations, which indicates that the homogeneity of the precipitation is good in most areas of China. For the non homogeneous stations, the change of location is one of the main causes. Applying the method of Rhtest, the series that have breakpoints are adjusted and the trends of the series are analyzed. It is found that the yearly precipitation trend has changed obviously and the homogeneity is improved well after adjustment.
2012, 40(6):922-927.
Abstract:
According to the actual requirements of meteorological information release, the types of the templates are designed beforehand based on the different displaying terminals, service levels and contents. The patterns of displaying pages are considered properly in template design, using the common page to enable the processing, managing, and maintaining of the templates. Texts and images in templates are withdrawn automatically from the real time database with SQL. To decrease the information quantity and keep the system stable, the fixed and real time information is treated differently. The picture products are given to show the actual display effect of the system.
According to the actual requirements of meteorological information release, the types of the templates are designed beforehand based on the different displaying terminals, service levels and contents. The patterns of displaying pages are considered properly in template design, using the common page to enable the processing, managing, and maintaining of the templates. Texts and images in templates are withdrawn automatically from the real time database with SQL. To decrease the information quantity and keep the system stable, the fixed and real time information is treated differently. The picture products are given to show the actual display effect of the system.
12 Design and Implementation of Prefecture Level Weather Forecast Production and Transmission System
2012, 40(6):928-932.
Abstract:
Base on the needs of the refinement forecast products and transmission system, the design, functions, and application of the Prefecture level Weather Forecast Production and Transmission System are described. The system was developed under the environment of PowerBuilder 7.0 and Windows 2000 operating system in PowerScript visual programming language. It consists of three subsystems (the human computer interaction, the forecast automatic transmission, and forecast check), can made various forecasting service products, such as the refinement forecast, short time forecast, forecast score, urban area forecast, peak hour forecast, and so on. The forecasts can be found on the local server at any time and can be uploaded to the provincial bureau manually or automatically. The system is a reliable and efficient forecasting platform for forecasters.
Base on the needs of the refinement forecast products and transmission system, the design, functions, and application of the Prefecture level Weather Forecast Production and Transmission System are described. The system was developed under the environment of PowerBuilder 7.0 and Windows 2000 operating system in PowerScript visual programming language. It consists of three subsystems (the human computer interaction, the forecast automatic transmission, and forecast check), can made various forecasting service products, such as the refinement forecast, short time forecast, forecast score, urban area forecast, peak hour forecast, and so on. The forecasts can be found on the local server at any time and can be uploaded to the provincial bureau manually or automatically. The system is a reliable and efficient forecasting platform for forecasters.
2012, 40(6):933-937.
Abstract:
At present, database systems such as Oracle and SQL Server are a preliminary application in automatic weather station data storage. The database performance is easy to maintain with a small number of AWS’s, but at the regional level or provincial level meteorological service, because of the large amount of AWS’s and the growing amount of data, the design and implementation of data storage is need to be paid great attention. In 2009, based on the Oracle 10 G database system, the Yangtze River Delta region AWS Database System was developed and established. The system carries out the processing and storing of AWS’s data in real time. The design of the massive database implementation, including event driven storage processing, large table partition, index, and SQL statement query optimization principles in the massive database, is discussed.
At present, database systems such as Oracle and SQL Server are a preliminary application in automatic weather station data storage. The database performance is easy to maintain with a small number of AWS’s, but at the regional level or provincial level meteorological service, because of the large amount of AWS’s and the growing amount of data, the design and implementation of data storage is need to be paid great attention. In 2009, based on the Oracle 10 G database system, the Yangtze River Delta region AWS Database System was developed and established. The system carries out the processing and storing of AWS’s data in real time. The design of the massive database implementation, including event driven storage processing, large table partition, index, and SQL statement query optimization principles in the massive database, is discussed.
2012, 40(6):938-948.
Abstract:
The intra srasonal oscillation of the atmosphere (ISO) mainly indicates the oscillation at a time scale of 30 to 60 days, one of the most remarkable oscillation phenomenans. As one of the most distinct low frequency systems, ISO has been paid great attention widely, and already obtained numerous meaningful results since the 1970s. ISO plays a crucial role in adjusting climate variability and influences weather and climate of China profoundly. A systemic summary is made of the researches on ISO in the recent years, with emphases on its structure, activity characteristics, influence on weather and climate, stimulation, and maintaining mechanisms. The prospects of further studies about ISO are discussed based on those summaries.
The intra srasonal oscillation of the atmosphere (ISO) mainly indicates the oscillation at a time scale of 30 to 60 days, one of the most remarkable oscillation phenomenans. As one of the most distinct low frequency systems, ISO has been paid great attention widely, and already obtained numerous meaningful results since the 1970s. ISO plays a crucial role in adjusting climate variability and influences weather and climate of China profoundly. A systemic summary is made of the researches on ISO in the recent years, with emphases on its structure, activity characteristics, influence on weather and climate, stimulation, and maintaining mechanisms. The prospects of further studies about ISO are discussed based on those summaries.
2012, 40(6):949-959.
Abstract:
In the high resolution model (6 to 3 km), there are still controversies for using the cumulus parameterization scheme. The impact of using different cloud precipitation schemes on the simulation of a hurricane is studied by using the WRF model at a grid spacing of 5 km, and the causes of the impact are investigated. The results indicate that even in this high resolution, the cumulus parameterization scheme can improve the simulations of TC tracks. The sophisticated mixed ice phase schemes have the greater advantage of simulating the TC tracks than the simple mixing ice phase schemes. The simulation of TC intensity is sensitive to the choice of cumulus parameterization schemes. The best simulation of precipitation can be obtained by employing only the microphysics scheme. Using the cumulus parameterization scheme can cause more false rainfall, but improve the simulation of the third day precipitation. By affecting the simulations of the typhoon asymmetrical structure, the cumulus parameterizations can improve the simulations of TC tracks. These findings provide a reference for typhoon simulation by using the high resolution model and improve the cumulus parameterization scheme.
In the high resolution model (6 to 3 km), there are still controversies for using the cumulus parameterization scheme. The impact of using different cloud precipitation schemes on the simulation of a hurricane is studied by using the WRF model at a grid spacing of 5 km, and the causes of the impact are investigated. The results indicate that even in this high resolution, the cumulus parameterization scheme can improve the simulations of TC tracks. The sophisticated mixed ice phase schemes have the greater advantage of simulating the TC tracks than the simple mixing ice phase schemes. The simulation of TC intensity is sensitive to the choice of cumulus parameterization schemes. The best simulation of precipitation can be obtained by employing only the microphysics scheme. Using the cumulus parameterization scheme can cause more false rainfall, but improve the simulation of the third day precipitation. By affecting the simulations of the typhoon asymmetrical structure, the cumulus parameterizations can improve the simulations of TC tracks. These findings provide a reference for typhoon simulation by using the high resolution model and improve the cumulus parameterization scheme.
2012, 40(6):960-968.
Abstract:
The Advanced Regional Prediction System model is used to simulate a precipitation case occurred from 18 to 22 September 2010 in the western North China complex topography. A set of sensitivity tests is also conducted to study the impact of cloud analysis on precipitation and temperature prediction. The results show： (1) The ARPS model for complex terrain has a very good adaptability. The comparison of ARPS prediction with local observation shows that ARPS performs very well both in start/stop time and spatial distribution of precipitation in two forecast process (24 h and 48 h); the precipitation of 24 h forecast corresponds with local observations，and the 48 h forecast tends to be bigger than local observations. (2) The ARPS model can also simulate temperature changes accurately, and the average absolute temperature error of interpolated 5 day forecast for six stations is only 2.69 ℃.（3） Cloud analysis can significantly improve the model initial field， especially the water substance, so that the bigger rainfall forecast at the strong precipitation center improved obviously, which indicates that the cloud analysis contributes to the success of precipitation forecasts, but the impact on temperature forecast is inconspicuous.
The Advanced Regional Prediction System model is used to simulate a precipitation case occurred from 18 to 22 September 2010 in the western North China complex topography. A set of sensitivity tests is also conducted to study the impact of cloud analysis on precipitation and temperature prediction. The results show： (1) The ARPS model for complex terrain has a very good adaptability. The comparison of ARPS prediction with local observation shows that ARPS performs very well both in start/stop time and spatial distribution of precipitation in two forecast process (24 h and 48 h); the precipitation of 24 h forecast corresponds with local observations，and the 48 h forecast tends to be bigger than local observations. (2) The ARPS model can also simulate temperature changes accurately, and the average absolute temperature error of interpolated 5 day forecast for six stations is only 2.69 ℃.（3） Cloud analysis can significantly improve the model initial field， especially the water substance, so that the bigger rainfall forecast at the strong precipitation center improved obviously, which indicates that the cloud analysis contributes to the success of precipitation forecasts, but the impact on temperature forecast is inconspicuous.
2012, 40(6):969-975.
Abstract:
By the use of the WRF (V3.3.1) model and the assimilation system, experiments are carried out with the numerical simulation scheme designed on the different boundary and initial conditions with the different assimilated element observation. The sensitivity impact analysis of the WRF model boundary conditions on the simulation of the heavy rainfall happened in the eastern Sichuan Basin is discussed. The results show that the WRF model is sensitive to the change of initial and boundary conditions. The change caused by the assimilation of ground temperature is more sensitive than that caused by the assimilation of the ground wind field. The sensitivities to the upper level relative humidity, wind, and vertical velocity are bigger than those to the lower level. During test, the sensitivities to lower temperature and unstable energy are bigger than those to the upper. The sensitivities caused by boundary conditions increase with time. The sensitivities caused by initial conditions decrease with time.
By the use of the WRF (V3.3.1) model and the assimilation system, experiments are carried out with the numerical simulation scheme designed on the different boundary and initial conditions with the different assimilated element observation. The sensitivity impact analysis of the WRF model boundary conditions on the simulation of the heavy rainfall happened in the eastern Sichuan Basin is discussed. The results show that the WRF model is sensitive to the change of initial and boundary conditions. The change caused by the assimilation of ground temperature is more sensitive than that caused by the assimilation of the ground wind field. The sensitivities to the upper level relative humidity, wind, and vertical velocity are bigger than those to the lower level. During test, the sensitivities to lower temperature and unstable energy are bigger than those to the upper. The sensitivities caused by boundary conditions increase with time. The sensitivities caused by initial conditions decrease with time.
2012, 40(6):976-982.
Abstract:
Using the monthly temperature from 81 stations of Jiangxi and the sea surface temperature (SST) data from NOAA, the possible relation between winter (DJF) temperature anomalies in Jiangxi and Global SSTA is analyzed. The coupling relationship between the anomalous distribution in winter air temperature and the variations of SST is studied with the Singular Value Decomposition (SVD) analysis method. The interaction between key areas is also discussed with the lead lag correlation analysis and SVD methods. The main results are as follows: (1) The winter air the temperature anomaly of Jiangxi had obviously identical distribution with concurrent SSTs over the Indian Ocean (10°S to 20°N, 54° to 90°E) and Northwest Pacific Ocean key area (20° to 40°N, 120° to 180°E), and the preceding August to September SSTs over the North Atlantic Ocean key area (24° to 44°N, 20° to 60°W); (2) The correlation between the warmer seawater and warmer winter in Jiangxi was better over the Northwest Pacific Ocean key area than that over the Indian Ocean, and the correlation between cooler seawater and cooler winter in Jiangxi was better over the Pacific Ocean than that over the Northwest Pacific Ocean. The SSTAs over the Indian Ocean and Northwest Pacific Ocean key areas can be used to correct the influence of the North Atlantic Ocean SSTA in winter air temperature prediction in Jiangxi.
Using the monthly temperature from 81 stations of Jiangxi and the sea surface temperature (SST) data from NOAA, the possible relation between winter (DJF) temperature anomalies in Jiangxi and Global SSTA is analyzed. The coupling relationship between the anomalous distribution in winter air temperature and the variations of SST is studied with the Singular Value Decomposition (SVD) analysis method. The interaction between key areas is also discussed with the lead lag correlation analysis and SVD methods. The main results are as follows: (1) The winter air the temperature anomaly of Jiangxi had obviously identical distribution with concurrent SSTs over the Indian Ocean (10°S to 20°N, 54° to 90°E) and Northwest Pacific Ocean key area (20° to 40°N, 120° to 180°E), and the preceding August to September SSTs over the North Atlantic Ocean key area (24° to 44°N, 20° to 60°W); (2) The correlation between the warmer seawater and warmer winter in Jiangxi was better over the Northwest Pacific Ocean key area than that over the Indian Ocean, and the correlation between cooler seawater and cooler winter in Jiangxi was better over the Pacific Ocean than that over the Northwest Pacific Ocean. The SSTAs over the Indian Ocean and Northwest Pacific Ocean key areas can be used to correct the influence of the North Atlantic Ocean SSTA in winter air temperature prediction in Jiangxi.
2012, 40(6):983-989.
Abstract:
Using the daily average data of NCEP 2.5°×2.5° and observed rainfall, on the base of comparative analysis of two heavy rainfall events in the Meiyu period in 2011, it is concluded: (1) The phases of the west jet over the Yangtze River for the two rainfall events were contrary, the former in the westerly airflow on the bottom of high pressure ridge, and the latter in the southwest flow before the trough. The circulation pattern (two troughs and one ridge) at 500 hPa were different，with the south trough of the former being shallow, and that of the latter being deep. The shear line at 700hPa of the former was formed by north and southwest winds and that of the latter was by east and southwest winds. (2) The water vapor of the former came from the west of the Bay of Bengal and the southeast of Subtropical; that of the latter came from the west of the Bay of Bengal mainly. (3) For both cases, the structure of the Meiyu front exhibited small humidity difference and temperature gradient, and the frontal zone moved northward first and southward, but the frontal zone position of the former was further south and that of the latter was further north; the duration of the former was long and that of the latter was short. The dry cold air of the former, which mainly came from the high level troposphere, was weak at lower levels and strong at upper levels, at the same time no clear cold air added to the north front. The dry cold air of the latter mainly came from upper levels, and there was a cold front frontal zone to the north of the front.
Using the daily average data of NCEP 2.5°×2.5° and observed rainfall, on the base of comparative analysis of two heavy rainfall events in the Meiyu period in 2011, it is concluded: (1) The phases of the west jet over the Yangtze River for the two rainfall events were contrary, the former in the westerly airflow on the bottom of high pressure ridge, and the latter in the southwest flow before the trough. The circulation pattern (two troughs and one ridge) at 500 hPa were different，with the south trough of the former being shallow, and that of the latter being deep. The shear line at 700hPa of the former was formed by north and southwest winds and that of the latter was by east and southwest winds. (2) The water vapor of the former came from the west of the Bay of Bengal and the southeast of Subtropical; that of the latter came from the west of the Bay of Bengal mainly. (3) For both cases, the structure of the Meiyu front exhibited small humidity difference and temperature gradient, and the frontal zone moved northward first and southward, but the frontal zone position of the former was further south and that of the latter was further north; the duration of the former was long and that of the latter was short. The dry cold air of the former, which mainly came from the high level troposphere, was weak at lower levels and strong at upper levels, at the same time no clear cold air added to the north front. The dry cold air of the latter mainly came from upper levels, and there was a cold front frontal zone to the north of the front.
2012, 40(6):990-995.
Abstract:
Based on the precipitable water vapor received from the ground based GPS and ground automatic stations, as well as weather data, a return flow snowfall in Hebei province is studied. The results show that: (1)GPS precipitable water vapor increased from southwest to northeast before the snow, corresponding to the warm and humid southwesterly flow, and decreased from north to south after the snow because of the clod high. (2) The main effect system was the high level trough in the first stage; GPS precipitable water vapor showed increasing trend, and the actual precipitation increased first and reduced then; the main effect system was the return flow in the second stage, and the actual precipitation occurred at the peak of GPS precipitable water vapor or during the decreasing phase. When the cold high moved from north to south, GPS precipitable water vapor decreased, and the actual precipitation weakened and stopped. (3) In the sounding stratification of the return flow snowfall, the high humidity layers were near the ground and the 700 hPa layer, and the low humidity layer was between the high humidity levels.
Based on the precipitable water vapor received from the ground based GPS and ground automatic stations, as well as weather data, a return flow snowfall in Hebei province is studied. The results show that: (1)GPS precipitable water vapor increased from southwest to northeast before the snow, corresponding to the warm and humid southwesterly flow, and decreased from north to south after the snow because of the clod high. (2) The main effect system was the high level trough in the first stage; GPS precipitable water vapor showed increasing trend, and the actual precipitation increased first and reduced then; the main effect system was the return flow in the second stage, and the actual precipitation occurred at the peak of GPS precipitable water vapor or during the decreasing phase. When the cold high moved from north to south, GPS precipitable water vapor decreased, and the actual precipitation weakened and stopped. (3) In the sounding stratification of the return flow snowfall, the high humidity layers were near the ground and the 700 hPa layer, and the low humidity layer was between the high humidity levels.
2012, 40(6):996-1001.
Abstract:
Based on the NCEP re analysis data, Doppler Radar products and FY satellite retrieval cloud parameters, the first snowfall process of 2009 in Tianjin area is analyzed. The research shows that: (1) The main synoptic systems caused this snowfall process were the eastward moving upper level trough and the surface inverted trough. (2) The snowfall echo showed the typical characteristics of stratiform cloud precipitation, with the echo intensity not exceeding 35 dBz, and at the ending of snowfall process, the echo top height descended. (3) The cloud particle effective radius maintained around 20 μm; during the snowfall process, the depth of supercooled cloud layer and cloud top height were larger, and the cloud top temperature was about -30 ℃; after the snowfall, the value of cloud particle effective radius, depth of supercooled cloud layer, and cloud top height decreased, while the value of cloud top temperature increased. (4) The correlativity between snowfall and cloud particle effective radius, depth of supercooled cloud layer, and cloud top height were positive, but that between cloud top temperature and snowfall was negative.
Based on the NCEP re analysis data, Doppler Radar products and FY satellite retrieval cloud parameters, the first snowfall process of 2009 in Tianjin area is analyzed. The research shows that: (1) The main synoptic systems caused this snowfall process were the eastward moving upper level trough and the surface inverted trough. (2) The snowfall echo showed the typical characteristics of stratiform cloud precipitation, with the echo intensity not exceeding 35 dBz, and at the ending of snowfall process, the echo top height descended. (3) The cloud particle effective radius maintained around 20 μm; during the snowfall process, the depth of supercooled cloud layer and cloud top height were larger, and the cloud top temperature was about -30 ℃; after the snowfall, the value of cloud particle effective radius, depth of supercooled cloud layer, and cloud top height decreased, while the value of cloud top temperature increased. (4) The correlativity between snowfall and cloud particle effective radius, depth of supercooled cloud layer, and cloud top height were positive, but that between cloud top temperature and snowfall was negative.
2012, 40(6):1002-1006.
Abstract:
Based on the data from June 2009 to May 2011 over the Tibetan plateau, the temporal and spatial distribution of lightning is analyzed. Results show that the average value of lightning intensity was 61.89 kA; the negative ground flash took up 78.2% of the total; and the average of negative ground flash intensity was 55.97 kA. The positive ground flash took up 21.8% of the total, and the average of negative ground flash intensity was 83.14 kA. The lightning flashes were mainly positive ground flashes, which took up 73% before rainy season. The positive ground flashes took only 9% during the rainy season. The daily variation of lightning frequency showed the obvious single peak pattern, with the high frequency period in 15:00-21:00 (the peak at about 17:00) and the low frequency period in 03:00-12:00. The lightning density distribution had obvious regional difference. The high density areas of lightning were the mid eastern Naqu, western Changdu, eastern Rikaze, and Shannan. The negative flashes had two high density centers: Jiali and Langkazi. The Cuona was also a positive high density center. The lightning intensity was higher in winter and lower in summer. The monthly average intensity was greater than 50 kA. A probability equation is set up according to the lightning intensity, the positive and the negative flash lightning intensity, and the corresponding cumulative frequency. The fitting rate between the measured values and the calculated is higher than 0.99.
Based on the data from June 2009 to May 2011 over the Tibetan plateau, the temporal and spatial distribution of lightning is analyzed. Results show that the average value of lightning intensity was 61.89 kA; the negative ground flash took up 78.2% of the total; and the average of negative ground flash intensity was 55.97 kA. The positive ground flash took up 21.8% of the total, and the average of negative ground flash intensity was 83.14 kA. The lightning flashes were mainly positive ground flashes, which took up 73% before rainy season. The positive ground flashes took only 9% during the rainy season. The daily variation of lightning frequency showed the obvious single peak pattern, with the high frequency period in 15:00-21:00 (the peak at about 17:00) and the low frequency period in 03:00-12:00. The lightning density distribution had obvious regional difference. The high density areas of lightning were the mid eastern Naqu, western Changdu, eastern Rikaze, and Shannan. The negative flashes had two high density centers: Jiali and Langkazi. The Cuona was also a positive high density center. The lightning intensity was higher in winter and lower in summer. The monthly average intensity was greater than 50 kA. A probability equation is set up according to the lightning intensity, the positive and the negative flash lightning intensity, and the corresponding cumulative frequency. The fitting rate between the measured values and the calculated is higher than 0.99.
2012, 40(6):1007-1012.
Abstract:
An ontology representation of severe weather based on the W3C standard is proposed. According to the understanding of the concept definition, naming and categorization, the concepts of severe weather are logically represented with a step function expression and a first order logic expression. The logical representation is applied in the ontology design, in which the class tree, the class of equivalent axiom, and the collections of object properties and data properties are built up, as well as the ontology library. By the intelligent agent, the surface observation of weather data is transformed into knowledge of meteorological disasters. The ontology library of the severe weathers built with the proposed representation is tested in the near real time GIS mapping and Web posting system. The positive performance in the automatic warning analysis of severe weather proved the efficiency of the ontology representation.
An ontology representation of severe weather based on the W3C standard is proposed. According to the understanding of the concept definition, naming and categorization, the concepts of severe weather are logically represented with a step function expression and a first order logic expression. The logical representation is applied in the ontology design, in which the class tree, the class of equivalent axiom, and the collections of object properties and data properties are built up, as well as the ontology library. By the intelligent agent, the surface observation of weather data is transformed into knowledge of meteorological disasters. The ontology library of the severe weathers built with the proposed representation is tested in the near real time GIS mapping and Web posting system. The positive performance in the automatic warning analysis of severe weather proved the efficiency of the ontology representation.
2012, 40(6):1013-1017.
Abstract:
The earthing resistance is one of important technical parameters to reflect the earthing effect of lightning protection system; however, the testing of earthing resistance is closely related with its environment. According to the theory of electric capacity and electromagnetic fields, the influencing mechanisms of external interference sources, such as high voltage transmission line, television transmitting station or base station, underground cable, tracks etc., on earthing resistance testers are studied. The results show that the external interference sources seriously interfere the measuring of earthing resistance testing devices through capacitive coupling, resistive coupling, and inductive coupling. On this basis, it is concluded that the shield method and the equipotential bonding measuring method are effective for preventing interference on earthing resistance testing.
The earthing resistance is one of important technical parameters to reflect the earthing effect of lightning protection system; however, the testing of earthing resistance is closely related with its environment. According to the theory of electric capacity and electromagnetic fields, the influencing mechanisms of external interference sources, such as high voltage transmission line, television transmitting station or base station, underground cable, tracks etc., on earthing resistance testers are studied. The results show that the external interference sources seriously interfere the measuring of earthing resistance testing devices through capacitive coupling, resistive coupling, and inductive coupling. On this basis, it is concluded that the shield method and the equipotential bonding measuring method are effective for preventing interference on earthing resistance testing.
2012, 40(6):1018-1024.
Abstract:
Analysis and calculation of different ground electrical parameter variation caused by surface soil moisture are conducted, and the impact of the variation on the propagation of the electromagnetic field of lightning return strokes is examined. A two dimension fraction Brown motion model is presented for describing the natural rough surface. The adopted method is based on the Cooray and Wait approximate calculation, taking advantage of the soil electrical parameter equivalent model put forward by Scott. It is shown that the impact of surface humidity on lightning electromagnetic field propagation can not be ignored and the impact on the horizontal electric field is larger than that on the vertical electric field; the peak value of the horizontal electric field is inversely proportional to the soil moisture. With the increasing humidity, the increase of both vertical and horizontal electric fields deceases with time, but the peak values hardly change. Therefore, the impact of soil moisture must be considered when studying lightning electromagnetic radiation environments because the rainfall always accompanies with thunderstorms.
Analysis and calculation of different ground electrical parameter variation caused by surface soil moisture are conducted, and the impact of the variation on the propagation of the electromagnetic field of lightning return strokes is examined. A two dimension fraction Brown motion model is presented for describing the natural rough surface. The adopted method is based on the Cooray and Wait approximate calculation, taking advantage of the soil electrical parameter equivalent model put forward by Scott. It is shown that the impact of surface humidity on lightning electromagnetic field propagation can not be ignored and the impact on the horizontal electric field is larger than that on the vertical electric field; the peak value of the horizontal electric field is inversely proportional to the soil moisture. With the increasing humidity, the increase of both vertical and horizontal electric fields deceases with time, but the peak values hardly change. Therefore, the impact of soil moisture must be considered when studying lightning electromagnetic radiation environments because the rainfall always accompanies with thunderstorms.
2012, 40(6):1025-1029.
Abstract:
A case study is conducted on the lightning induced interior wall collapse event on 13 September 2010 in Yiwu, Zhejiang Province. The intensity of lightning, the waveform of air shock waves, and the solidity of partition walls are analyzed in detail. The results indicate that being lack of certain anti vibration capacity for there was no any wall reinforcement measure is the internal cause; the wind pressure induced by the strong wind (force 10) on that day had a certain impact; the main cause is the strong lightning, which had a negative current intensity of 416.798 kA, far greater than the general disaster strength of 100 to 200 kA; the air shock wave from lightning discharges at short range made wall collapsed.
A case study is conducted on the lightning induced interior wall collapse event on 13 September 2010 in Yiwu, Zhejiang Province. The intensity of lightning, the waveform of air shock waves, and the solidity of partition walls are analyzed in detail. The results indicate that being lack of certain anti vibration capacity for there was no any wall reinforcement measure is the internal cause; the wind pressure induced by the strong wind (force 10) on that day had a certain impact; the main cause is the strong lightning, which had a negative current intensity of 416.798 kA, far greater than the general disaster strength of 100 to 200 kA; the air shock wave from lightning discharges at short range made wall collapsed.
2012, 40(6):1030-1038.
Abstract:
Based on the data from meteorological observation stations in Shandong Province from 1961 to 2008, the yearly average climatic potential productivity of grain crops (winter wheat and summer maize) is calculated by the phase correction method, and the spatial and temporal variation characteristics of climatic potential productivity of grain crops are analyzed by the decomposition method of the empirical orthogonal function. The results show that there were obvious inter annual fluctuation and regional difference in climatic potential productivity of grain crops. The productivity in a rich harvest year was 3 to 9 times of that in a poor harvest year for winter wheat and 2 to 3 times of that for summer maize. The area of high productivity of grain crops was in the south part of Shandong Province with better hydro thermal conditions and low productivity was in the east coastal area of the Shandong Peninsula. The annual variation of the yields was consistent with that of climatic potential productivity. The yields of grain crops, especially for summer maize, were affected remarkably by climatic condition in growth season in Shandong Province. There was good spatial consistence in climatic potential productivity of grain crops in the whole province. The grain crop productivity fluctuated due to unstable monsoon climate. Regional complementarity of grain production was relatively poor in Shandong Province.
Based on the data from meteorological observation stations in Shandong Province from 1961 to 2008, the yearly average climatic potential productivity of grain crops (winter wheat and summer maize) is calculated by the phase correction method, and the spatial and temporal variation characteristics of climatic potential productivity of grain crops are analyzed by the decomposition method of the empirical orthogonal function. The results show that there were obvious inter annual fluctuation and regional difference in climatic potential productivity of grain crops. The productivity in a rich harvest year was 3 to 9 times of that in a poor harvest year for winter wheat and 2 to 3 times of that for summer maize. The area of high productivity of grain crops was in the south part of Shandong Province with better hydro thermal conditions and low productivity was in the east coastal area of the Shandong Peninsula. The annual variation of the yields was consistent with that of climatic potential productivity. The yields of grain crops, especially for summer maize, were affected remarkably by climatic condition in growth season in Shandong Province. There was good spatial consistence in climatic potential productivity of grain crops in the whole province. The grain crop productivity fluctuated due to unstable monsoon climate. Regional complementarity of grain production was relatively poor in Shandong Province.
2012, 40(6):1039-1043.
Abstract:
Soil moisture and vegetation conditions are the most important and direct indexes in drought monitoring, and the retrieval accuracy is important in the judgment of drought degree. A new model of Enhanced Surface Water Content Index (ESWCI), which adds the channel 1 of MODIS based on the Model of SWCI and the characteristic of chlorophyll spectrum, is put forward. The validation results show that ESWCI is more sensitive for surface water content retrieval than SWCI, and suits for regional drought monitoring, which is conducive to the improvement of the accuracy of soil drought monitoring in real time.
Soil moisture and vegetation conditions are the most important and direct indexes in drought monitoring, and the retrieval accuracy is important in the judgment of drought degree. A new model of Enhanced Surface Water Content Index (ESWCI), which adds the channel 1 of MODIS based on the Model of SWCI and the characteristic of chlorophyll spectrum, is put forward. The validation results show that ESWCI is more sensitive for surface water content retrieval than SWCI, and suits for regional drought monitoring, which is conducive to the improvement of the accuracy of soil drought monitoring in real time.
2012, 40(6):1044-1049.
Abstract:
The influence of meteorological factors on acid rains is investigated on the basis of observation data on acid rains and environmental meteorological factors from the urban area of Hangzhou from 1996 to 2010. The research indicates that the low incidence of acid rains occurred under heavy precipitation weather, the lower pH value was more likely to happen in continuous rainy weather. The average pH of rainwater was low under north wind conditions, and high under southwest winds. The pH value of precipitation was as low as 4.51 and the incidence of acid rain was up to 85.3% under the control of high pressure in Hangzhou; the pH value peaked 5.11 and the lowest acid rain rate was 66.5% in thunderstorm weather. The results show that different weather types led to varying degrees of pollutant diffusion, dilution, and wet deposition, which are also the main reasons for acid rain pollution.
The influence of meteorological factors on acid rains is investigated on the basis of observation data on acid rains and environmental meteorological factors from the urban area of Hangzhou from 1996 to 2010. The research indicates that the low incidence of acid rains occurred under heavy precipitation weather, the lower pH value was more likely to happen in continuous rainy weather. The average pH of rainwater was low under north wind conditions, and high under southwest winds. The pH value of precipitation was as low as 4.51 and the incidence of acid rain was up to 85.3% under the control of high pressure in Hangzhou; the pH value peaked 5.11 and the lowest acid rain rate was 66.5% in thunderstorm weather. The results show that different weather types led to varying degrees of pollutant diffusion, dilution, and wet deposition, which are also the main reasons for acid rain pollution.
30 Characteistic Analysis of Acid Rains at Nangong and Its Relationship with Meteorological Conditions
2012, 40(6):1050-1055.
Abstract:
The statistical characteristics of precipitation acidity and conductivity at Nangong are discussed by means of the acid rain monitoring data from 2006 to 2009. Results show that the average precipitation pH is 5.22, with the lowest being 3.08; the averaged precipitation conductivity is 94.1 μS/cm with the highest value being 529.0 μS/cm for the 4 years; the acid rain frequency (pH<5.6) is 63%, which accounts for 80% of total precipitation amount of the four years; the severe acid rain frequency (pH<4.5) is 28%. Nangong is an area suffered from acid rain pollution relatively heavy in North China. The acid rain frequency shows a seasonal variation, high in autumn and low in spring. Consequently, the precipitation pH is low in autumn and high in spring. The relationships of precipitation acidity variation with surface wind conditions, precipitation amount, and precipitation types (including fog) are also discussed.The acid rain frequency in the daytime (10:00 to 16:00) is only 31%, much lower than that in the nighttime (72%). The diurnal variation of local PM10 can be attributed to the differences of precipitation acidities in the daytime and nighttime.
The statistical characteristics of precipitation acidity and conductivity at Nangong are discussed by means of the acid rain monitoring data from 2006 to 2009. Results show that the average precipitation pH is 5.22, with the lowest being 3.08; the averaged precipitation conductivity is 94.1 μS/cm with the highest value being 529.0 μS/cm for the 4 years; the acid rain frequency (pH<5.6) is 63%, which accounts for 80% of total precipitation amount of the four years; the severe acid rain frequency (pH<4.5) is 28%. Nangong is an area suffered from acid rain pollution relatively heavy in North China. The acid rain frequency shows a seasonal variation, high in autumn and low in spring. Consequently, the precipitation pH is low in autumn and high in spring. The relationships of precipitation acidity variation with surface wind conditions, precipitation amount, and precipitation types (including fog) are also discussed.The acid rain frequency in the daytime (10:00 to 16:00) is only 31%, much lower than that in the nighttime (72%). The diurnal variation of local PM10 can be attributed to the differences of precipitation acidities in the daytime and nighttime.
2012, 40(6):1056-1060.
Abstract:
Based on the precipitation data from the regional weather stations over Xi’an and the data of 1∶10000 geography information，population density, house floor space, local average GDP and so on, by means of weighting synthesis method, the regionalization is conducted in the aspects of sensitivity, risk, vulnerability, and capability of disaster prevention and reduction. Simultaneously, a more scientific and reasonably urban waterlogging disaster risk index of regionalization is devised by simulating the waterlogging distributed situation using the Xi’an Severeg Precipitation Waterlogging Disaster Forecast System, which has been put to operational use.
Based on the precipitation data from the regional weather stations over Xi’an and the data of 1∶10000 geography information，population density, house floor space, local average GDP and so on, by means of weighting synthesis method, the regionalization is conducted in the aspects of sensitivity, risk, vulnerability, and capability of disaster prevention and reduction. Simultaneously, a more scientific and reasonably urban waterlogging disaster risk index of regionalization is devised by simulating the waterlogging distributed situation using the Xi’an Severeg Precipitation Waterlogging Disaster Forecast System, which has been put to operational use.
2012, 40(6):1061-1067.
Abstract:
The public satisfaction with meteorological service embodies social benefits of public meteorological service, so there is significance for meteorological departments to study public satisfaction. Based on 9939 questionnaire from 24 cities in China, the impact factors about satisfaction with public meteorological service are studied by using the multiple linear regression method. The study shows that five independent variables (the public image of meteorological departments, whether the parlance of weather forecast is popular and easy to understand, the accuracy of weather forecast, the rich degree of weather forecast content, and the betimes of disastrous and sudden weather forecast and warning) have significant effect on the satisfaction of public meteorological service; however, individual factors have little effect on it; according to the regression coefficient, and the impact of public image of meteorological departments on the satisfaction of public meteorological service ranks first, next the betimes of warning and accuracy of forecast. The results of the study have important reference value for improving the satisfaction of public meteorological service for meteorological departments.
The public satisfaction with meteorological service embodies social benefits of public meteorological service, so there is significance for meteorological departments to study public satisfaction. Based on 9939 questionnaire from 24 cities in China, the impact factors about satisfaction with public meteorological service are studied by using the multiple linear regression method. The study shows that five independent variables (the public image of meteorological departments, whether the parlance of weather forecast is popular and easy to understand, the accuracy of weather forecast, the rich degree of weather forecast content, and the betimes of disastrous and sudden weather forecast and warning) have significant effect on the satisfaction of public meteorological service; however, individual factors have little effect on it; according to the regression coefficient, and the impact of public image of meteorological departments on the satisfaction of public meteorological service ranks first, next the betimes of warning and accuracy of forecast. The results of the study have important reference value for improving the satisfaction of public meteorological service for meteorological departments.
33 Benefit Evaluation and Service Demand Survey of Tourism Meteorological Service in Ningxia Province
Yan Xiaoyu
,
Liu Yulan
,
Li Jianping
,
Ma Shaiyan
,
Zhao Wei
,
Gou Xiaohui
,
Guo Xiaolei
,
Zhang Shaobo
2012, 40(6):1068-1074.
Abstract:
Using the specialist evaluation method, the assessment and survey of tourism meteorological service benefits and needs in 2010 are carried on Ningxia Province. The results show that the contribution rate of tourism meteorological service benefits was 0.203%, and the benefit value was 10.759 million yuan. High sensitive meteorological factors include rainfall, snow, wind force, road icing, dust storm weather, fog and haze, snow depth, lightning and thunderstorm, and so on; the critical value and the effective forecast period of these factors varied with elements and typical service stages; tourism meteorological service products can be divided into two types: popular science products and specialized meteorological service products, and the products are still mainly text based, up to 74%, and the product releasing approaches include mobile short message, network, specialized releasing system, email, etc.
Using the specialist evaluation method, the assessment and survey of tourism meteorological service benefits and needs in 2010 are carried on Ningxia Province. The results show that the contribution rate of tourism meteorological service benefits was 0.203%, and the benefit value was 10.759 million yuan. High sensitive meteorological factors include rainfall, snow, wind force, road icing, dust storm weather, fog and haze, snow depth, lightning and thunderstorm, and so on; the critical value and the effective forecast period of these factors varied with elements and typical service stages; tourism meteorological service products can be divided into two types: popular science products and specialized meteorological service products, and the products are still mainly text based, up to 74%, and the product releasing approaches include mobile short message, network, specialized releasing system, email, etc.
2012, 40(6):1075-1077.
Abstract:
The analysis of the evaporation records in July and August 2009 over Shandong Province indicate that the number of fault records in strong precipitation weather was up to 18.6, and the main reasons include that the observers’ understanding of the relevant observation stands was not correct, and that the checkers’ understanding of the stands was too inflexible, consequently making an arbitrary conclusion. Based on the evaporation data of Dezhou from 2000 to 2010 and the plain from 2008 to 2010 in strong precipitation weather, a comparison was conducted between before and after certain countermeasures being taking, and the results indicate that the liquid precipitation method by increasing the overflow barrel is best, but it is not applicable to solid precipitation; the covering method is simple, easy, suitable for both liquid and solid precipitation, but only suitable while there is an observer on duty. Therefore, appropriate measures should be taken according to the different natures of precipitation, to ensure the accuracy of evaporation records.
The analysis of the evaporation records in July and August 2009 over Shandong Province indicate that the number of fault records in strong precipitation weather was up to 18.6, and the main reasons include that the observers’ understanding of the relevant observation stands was not correct, and that the checkers’ understanding of the stands was too inflexible, consequently making an arbitrary conclusion. Based on the evaporation data of Dezhou from 2000 to 2010 and the plain from 2008 to 2010 in strong precipitation weather, a comparison was conducted between before and after certain countermeasures being taking, and the results indicate that the liquid precipitation method by increasing the overflow barrel is best, but it is not applicable to solid precipitation; the covering method is simple, easy, suitable for both liquid and solid precipitation, but only suitable while there is an observer on duty. Therefore, appropriate measures should be taken according to the different natures of precipitation, to ensure the accuracy of evaporation records.
2012, 40(6):1078-1080.
Abstract:
Power supply board failures occur frequently in CAWS600B automatic weather stations, often resulting in data missing. Because manufacturers did not provide the power supply board circuit diagram, troubleshooting is difficult. In order to quickly repair the power supply board faults and improve troubleshooting efficiency, based on the observation and analysis of the power supply board and the realted data, a detailed circuit diagram is presented, and a brief introduction is made to the working principles of the CAWS600B automatic weather station power supply. The analysis concludes that the main causes for the damage of the power supply board are: long term high electric voltage, small rated bridge electric current (BD1 ), large rated current of the primary transformer air switch, and high temperature in the collector. Some specific suggestions for improvement are given for observers as reference in practical maintenance.
Power supply board failures occur frequently in CAWS600B automatic weather stations, often resulting in data missing. Because manufacturers did not provide the power supply board circuit diagram, troubleshooting is difficult. In order to quickly repair the power supply board faults and improve troubleshooting efficiency, based on the observation and analysis of the power supply board and the realted data, a detailed circuit diagram is presented, and a brief introduction is made to the working principles of the CAWS600B automatic weather station power supply. The analysis concludes that the main causes for the damage of the power supply board are: long term high electric voltage, small rated bridge electric current (BD1 ), large rated current of the primary transformer air switch, and high temperature in the collector. Some specific suggestions for improvement are given for observers as reference in practical maintenance.
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.