Volume 42,Issue 4,2014 Table of Contents
Li Feng
,
Qin Shiguang
,
Zhou Wei
,
Xu Mingyi
,
Zhang Lejian
,
Zhou Qing
,
Xia Yuancai
,
Cao Tingting
,
Liang Haihe
2014, 42(4):539-544.
Abstract:
By analyzing the status quo of the integrated atmospheric observing monitoring operation and system platform, operational developing ideas and a scientific design on operational system are presented.The results indicate that the monitoring operation should be a center of the entire logistics flow, with the functions of monitoring, guiding, deploying, and managing and should form an interactive system among equipment monitoring, maintenance, logistics, and assessment jobs.The system platform should breakthrough the old technical method to devise an new technique of multi information interactive verification with equipment status, manual information, and data quality check results.
By analyzing the status quo of the integrated atmospheric observing monitoring operation and system platform, operational developing ideas and a scientific design on operational system are presented.The results indicate that the monitoring operation should be a center of the entire logistics flow, with the functions of monitoring, guiding, deploying, and managing and should form an interactive system among equipment monitoring, maintenance, logistics, and assessment jobs.The system platform should breakthrough the old technical method to devise an new technique of multi information interactive verification with equipment status, manual information, and data quality check results.
2 Numerical Simulation of Effect of 325 m Meteorological Tower on Wind Speed Measurements in Beijing
2014, 42(4):545-549.
Abstract:
When using equipment mounted on a meteorological tower to measure wind speeds, the body of the tower will affect and modify the local flow field, produce turbulence around it and wake behind, leading to the measurement flow distortion relative to the true wind flow.A widely applicable CFD software (Fluent) is used to simulate the flow around the Beijing 325 m lattice type meteorological tower, calculate the upstream and downstream flow distortions at the measurement points of the booms, and get the relationship between the distortions and wind directions and wind speeds.The results show that the errors of wind speeds at measurement points are all less than 5% when the booms located on the windward side.This is consistent with the observation and verifies the reliability of the design of the booms of the 325 m meteorological tower.
When using equipment mounted on a meteorological tower to measure wind speeds, the body of the tower will affect and modify the local flow field, produce turbulence around it and wake behind, leading to the measurement flow distortion relative to the true wind flow.A widely applicable CFD software (Fluent) is used to simulate the flow around the Beijing 325 m lattice type meteorological tower, calculate the upstream and downstream flow distortions at the measurement points of the booms, and get the relationship between the distortions and wind directions and wind speeds.The results show that the errors of wind speeds at measurement points are all less than 5% when the booms located on the windward side.This is consistent with the observation and verifies the reliability of the design of the booms of the 325 m meteorological tower.
2014, 42(4):550-555.
Abstract:
Based on the general investigation of manually observed historical haze records from 1951 to 2008 in 105 national weather stations in Xinjiang, it is found that the historical manual haze records do not accord with the actual situation. In order to explore the causes of these anomalies, by means of the historical data statistics, questionnaires, inductive analysis method, as well as the views and suggestions from observers, forecasters, and management personnel about haze monitoring, main problems in haze monitoring are summarized, and optimization strategies and measures for the problems are presented, which have been applied in meteorological stations in Xinjiang and achieved good results.
Based on the general investigation of manually observed historical haze records from 1951 to 2008 in 105 national weather stations in Xinjiang, it is found that the historical manual haze records do not accord with the actual situation. In order to explore the causes of these anomalies, by means of the historical data statistics, questionnaires, inductive analysis method, as well as the views and suggestions from observers, forecasters, and management personnel about haze monitoring, main problems in haze monitoring are summarized, and optimization strategies and measures for the problems are presented, which have been applied in meteorological stations in Xinjiang and achieved good results.
2014, 42(4):556-562.
Abstract:
Weather radar estimation for regional rainfall is an important field of its application, and to improve the accuracy and stability of regional precipitation estimation by means of radar data is an important task for meteorological radar service.The theoretical basis and development of ensemble forecasting are reviewed, and the methods and products are summarized.Previously used eight radar estimation methods for regional precipitation are systematically analyzed from the aspect of basic principles and characteristics.On this basis, the applicability of ensemble forecast theory in the field of radar estimates for regional precipitation is further discussed. A conceptual model and two methods for integrated regional precipitation estimation are proposed, which provides theoretical support for further applied research.
Weather radar estimation for regional rainfall is an important field of its application, and to improve the accuracy and stability of regional precipitation estimation by means of radar data is an important task for meteorological radar service.The theoretical basis and development of ensemble forecasting are reviewed, and the methods and products are summarized.Previously used eight radar estimation methods for regional precipitation are systematically analyzed from the aspect of basic principles and characteristics.On this basis, the applicability of ensemble forecast theory in the field of radar estimates for regional precipitation is further discussed. A conceptual model and two methods for integrated regional precipitation estimation are proposed, which provides theoretical support for further applied research.
2014, 42(4):563-569.
Abstract:
The wind profile radar has been widely used in many fields of the national economy.The application is not just confined to wind field data, and such information as echo intensity, signal noise ratio, and spectral width of speeds is more and more applied. It is very important to carry out the calibration of the wind profile radar. Taking CFL 03 wind profile radar as an example, a wind profile radar automatic calibration technology is introduced from technology design to signal process.The system composition and realization are discussed, and the radar is tested with outside measuring instrument.The machine test and built in automatic calibration results are compared. It is concluded that the precision of the automatic calibration system meets the requirements of radar operation and the design goal has been achieved.
The wind profile radar has been widely used in many fields of the national economy.The application is not just confined to wind field data, and such information as echo intensity, signal noise ratio, and spectral width of speeds is more and more applied. It is very important to carry out the calibration of the wind profile radar. Taking CFL 03 wind profile radar as an example, a wind profile radar automatic calibration technology is introduced from technology design to signal process.The system composition and realization are discussed, and the radar is tested with outside measuring instrument.The machine test and built in automatic calibration results are compared. It is concluded that the precision of the automatic calibration system meets the requirements of radar operation and the design goal has been achieved.
2014, 42(4):570-574.
Abstract:
Using the method of illustration method, the compositions, characteristics and roles of RDA adaptation parameters for CINRAD/SA weather radar are introduced systematically.The important applications of adaptation parameters for CINRAD/SA weather radar in radar maintenance and calibrations are embodied with an instance, to help radar maintenance technicians to use the adaptation parameters well.Experiences show that adaptation parameters play an important role in intelligent management, operational control, maintenance, calibrations, alarms, signal processing and data generation, etc., of CINRAD/SA weather radar.To understand systematically and apply fully adaptation parameters has practical significance to the efficient and reliable operating of weather radar.
Using the method of illustration method, the compositions, characteristics and roles of RDA adaptation parameters for CINRAD/SA weather radar are introduced systematically.The important applications of adaptation parameters for CINRAD/SA weather radar in radar maintenance and calibrations are embodied with an instance, to help radar maintenance technicians to use the adaptation parameters well.Experiences show that adaptation parameters play an important role in intelligent management, operational control, maintenance, calibrations, alarms, signal processing and data generation, etc., of CINRAD/SA weather radar.To understand systematically and apply fully adaptation parameters has practical significance to the efficient and reliable operating of weather radar.
2014, 42(4):575-579.
Abstract:
The working state of the magnetic field power supply control circuits for CINRAD/SA Radar is described. Diagrams of the corresponding standard waveforms are given by means of debugging the driving signals of FET and the control panel, voltage waveforms between electrodes of IGBT modules, and some other test points of the circuits. After debugging the output voltage, the voltage protection of power supply, and the current protection of focus coil by steps, the flowchart of fault treatment is accomplished with the physical test points, real fault phenomena, and solutions. Based on the practical experiences, correlative troubleshooting points and solutions are summarized, aiming to offer some references for the spot fault treatment of radar magnetic field power supply.
The working state of the magnetic field power supply control circuits for CINRAD/SA Radar is described. Diagrams of the corresponding standard waveforms are given by means of debugging the driving signals of FET and the control panel, voltage waveforms between electrodes of IGBT modules, and some other test points of the circuits. After debugging the output voltage, the voltage protection of power supply, and the current protection of focus coil by steps, the flowchart of fault treatment is accomplished with the physical test points, real fault phenomena, and solutions. Based on the practical experiences, correlative troubleshooting points and solutions are summarized, aiming to offer some references for the spot fault treatment of radar magnetic field power supply.
2014, 42(4):580-584.
Abstract:
Making full use of the graphical user interface of the L band radar soft panel can realize the monitoring, adjusting, and controlling of radar and provide technical parameters for the maintenance of radar. The components and characteristics of the L band radar soft panel are introduced, and the virtual measuring instrument, virtual switches and buttons, and the functions of each component in the real time detecting information window are analyzed. Based on information provided by the soft panel (normal state, fault phenomenon), failure causes and faulted parts are discussed.Practice has proved that radar parameters, performance parameters, and real time data provided by the soft panel are irreplaceable in the operation, maintenance, calibration, and overhaul of radar.
Making full use of the graphical user interface of the L band radar soft panel can realize the monitoring, adjusting, and controlling of radar and provide technical parameters for the maintenance of radar. The components and characteristics of the L band radar soft panel are introduced, and the virtual measuring instrument, virtual switches and buttons, and the functions of each component in the real time detecting information window are analyzed. Based on information provided by the soft panel (normal state, fault phenomenon), failure causes and faulted parts are discussed.Practice has proved that radar parameters, performance parameters, and real time data provided by the soft panel are irreplaceable in the operation, maintenance, calibration, and overhaul of radar.
2014, 42(4):585-588.
Abstract:
The filament power of SA radar transmitters was tracked in the actual application process, and the causes of the charred power driver circuit board and treatment approaches are described.There are design defects in the protective filament power of the existing SA weather radar transmitter, often leading to destructive faults, especially when the drive signal supply becomes instable, and two half bridge driver switch are often breakdown, resulting in excessive drive currents and burnt circuit boards.Through the actual maintenance and circuit analysis, it is found that this problem can be solved, as long as the self protection function of the filament power supply is appropriately enhanced and the control circuit is improved partially.When the drive signal instability leads to abnormal power output, the filament power receives the signals from the radar system quickly, and strong power supply can be cut off automatically, preventing the high current of the drive signals from passing through the drive circuit to reduce the impact of the filament supply on the switch, so to avoid subsequent devastating failure.The trial operation of the improved filament supply in some radar indicates that the result is satisfactory.
The filament power of SA radar transmitters was tracked in the actual application process, and the causes of the charred power driver circuit board and treatment approaches are described.There are design defects in the protective filament power of the existing SA weather radar transmitter, often leading to destructive faults, especially when the drive signal supply becomes instable, and two half bridge driver switch are often breakdown, resulting in excessive drive currents and burnt circuit boards.Through the actual maintenance and circuit analysis, it is found that this problem can be solved, as long as the self protection function of the filament power supply is appropriately enhanced and the control circuit is improved partially.When the drive signal instability leads to abnormal power output, the filament power receives the signals from the radar system quickly, and strong power supply can be cut off automatically, preventing the high current of the drive signals from passing through the drive circuit to reduce the impact of the filament supply on the switch, so to avoid subsequent devastating failure.The trial operation of the improved filament supply in some radar indicates that the result is satisfactory.
2014, 42(4):589-592.
Abstract:
The self developed weather station business integration platform is introduced, which is an extension of the operational software platform used widely in weather observation stations.The platform achieves such functions as operational monitoring, communication link monitoring, data quality checking, major weather event prompting, automatic alarming, workflow displaying, automatic scheduling, quality report generating, equipment managing, and communication quality assessing.The integrated use of 3G mobile communication and information technology plays an important role in the quality improvement of meteorological observation operation and workload reduction.
The self developed weather station business integration platform is introduced, which is an extension of the operational software platform used widely in weather observation stations.The platform achieves such functions as operational monitoring, communication link monitoring, data quality checking, major weather event prompting, automatic alarming, workflow displaying, automatic scheduling, quality report generating, equipment managing, and communication quality assessing.The integrated use of 3G mobile communication and information technology plays an important role in the quality improvement of meteorological observation operation and workload reduction.
2014, 42(4):593-596.
Abstract:
The static three point measurement method is presented, which can be applied in field calibration of the wind direction measurement system for automatic meteorological stations, aiming to solve the problem of incomplete coverage of wind direction indication calibration angles, namely data missing during wind direction calibration. The validity and reliability of the calibration method are demonstrated through the theoretical analysis and experimental comparison according to the coding principles and regular pattern of wind direction values of the Gray Code wind direction sensor. The problem of data missing during the field wind direction calibration can be well solved by using the method, and the calibration data are accurate and reliable.The method is applicable during practical field application.This method can be recommended for indoor verification of wind direction values currently.
The static three point measurement method is presented, which can be applied in field calibration of the wind direction measurement system for automatic meteorological stations, aiming to solve the problem of incomplete coverage of wind direction indication calibration angles, namely data missing during wind direction calibration. The validity and reliability of the calibration method are demonstrated through the theoretical analysis and experimental comparison according to the coding principles and regular pattern of wind direction values of the Gray Code wind direction sensor. The problem of data missing during the field wind direction calibration can be well solved by using the method, and the calibration data are accurate and reliable.The method is applicable during practical field application.This method can be recommended for indoor verification of wind direction values currently.
2014, 42(4):597-600.
Abstract:
According to the field experiences from the maintenance practice in an automatic weather station in recent years, various kinds of common faults for SL3 1 tilting rain sensors are classifieds, based on the relevant technical requirements and design principles of other similar instruments.Combined with the specific circumstances of the annual maximum precipitation in Tibet, the improvement measures and suggestions for the water intake, electrical, and base components are put forward, to reduce the equipment failure frequency and improve the accuracy of observation. In order to ensure the calibration of instruments according with the accuracy and comparative requirements, the problems encountered in the field maintenance of equipment are summarized, and a self made special equipment box for storing core components is introduced, to improve the efficiency of field maintenance.
According to the field experiences from the maintenance practice in an automatic weather station in recent years, various kinds of common faults for SL3 1 tilting rain sensors are classifieds, based on the relevant technical requirements and design principles of other similar instruments.Combined with the specific circumstances of the annual maximum precipitation in Tibet, the improvement measures and suggestions for the water intake, electrical, and base components are put forward, to reduce the equipment failure frequency and improve the accuracy of observation. In order to ensure the calibration of instruments according with the accuracy and comparative requirements, the problems encountered in the field maintenance of equipment are summarized, and a self made special equipment box for storing core components is introduced, to improve the efficiency of field maintenance.
2014, 42(4):601-604.
Abstract:
By the end of 2012, the Beidou Satellite Navigation System (BDS) has covered the Asia Pacific region, the gradual replacing of GPS with BDS， which is the main detection approach in ground water vapor research， becomes an important direction for meteorological servicce. The construction of reference stations of the BDS water vapor and ionosphere monitoring system is introduced emphatically by means of the existing GPS base stations in Hubei Province, including the existing GPS base stations, as well as the location selection, detecting environmental testing, and equipment installation of reference stations for the BDS water vapor and ionosphere monitoring system.As the first BDS water vapor and ionosphere monitoring system in China, the building of Hubei Province BDS reference stations has certain referential value for future BDS reference station construction.
By the end of 2012, the Beidou Satellite Navigation System (BDS) has covered the Asia Pacific region, the gradual replacing of GPS with BDS， which is the main detection approach in ground water vapor research， becomes an important direction for meteorological servicce. The construction of reference stations of the BDS water vapor and ionosphere monitoring system is introduced emphatically by means of the existing GPS base stations in Hubei Province, including the existing GPS base stations, as well as the location selection, detecting environmental testing, and equipment installation of reference stations for the BDS water vapor and ionosphere monitoring system.As the first BDS water vapor and ionosphere monitoring system in China, the building of Hubei Province BDS reference stations has certain referential value for future BDS reference station construction.
2014, 42(4):605-611.
Abstract:
On the basis of IDW, combining with temperature change with height and relationship between temperature field and pressure field at each observation station, the interpolation algorithm of temperature data from ground meteorological stations is improved. The experimental data are analyzed from the aspects of the relationship between search radius and distance weight coefficient and the number of stations in the fixed search radius and distance weighting coefficient to find the best algorithm parameters and minimum error. The improved interpolation algorithm is applied to the quality control of temperature observation data. The results show that the improved algorithm can evidently improve the interpolation accuracy resulted from the near surface temperature inversion.In the eastern China where stations are densely distributed, the sensitivity of temperature test can be up to 1 to 5 ℃.
On the basis of IDW, combining with temperature change with height and relationship between temperature field and pressure field at each observation station, the interpolation algorithm of temperature data from ground meteorological stations is improved. The experimental data are analyzed from the aspects of the relationship between search radius and distance weight coefficient and the number of stations in the fixed search radius and distance weighting coefficient to find the best algorithm parameters and minimum error. The improved interpolation algorithm is applied to the quality control of temperature observation data. The results show that the improved algorithm can evidently improve the interpolation accuracy resulted from the near surface temperature inversion.In the eastern China where stations are densely distributed, the sensitivity of temperature test can be up to 1 to 5 ℃.
2014, 42(4):612-616.
Abstract:
In order to increase the availability of automatic weather station data, a data quality control algorithm for automatic weather stations based on association rules mining is proposed.Taking the relationship between relative humidity and wind direction and speed changes as the example, some possible association rules among observation items are summarized to guide the installation of the expert knowledge rule base that is suit for different areas and climate characteristics.The goal is to perfect the data quality control system for automatic weather stations and provide more accurate meteorological observation data for weather forecasts and meteorological service.The dependability of the expert knowledge rule base with certain practical value is verified.
In order to increase the availability of automatic weather station data, a data quality control algorithm for automatic weather stations based on association rules mining is proposed.Taking the relationship between relative humidity and wind direction and speed changes as the example, some possible association rules among observation items are summarized to guide the installation of the expert knowledge rule base that is suit for different areas and climate characteristics.The goal is to perfect the data quality control system for automatic weather stations and provide more accurate meteorological observation data for weather forecasts and meteorological service.The dependability of the expert knowledge rule base with certain practical value is verified.
2014, 42(4):617-623.
Abstract:
The test procedures and result analysis of the comparative observation experiment on some present weather sensors at the Beijing Meteorological Observatory and Lushan Meteorological Service from December 2011 to June 2012 are described. There were three types of sensors tested in the 7 month experiment, each equipped with three sets provided by three manufactures. The experiment used the measurements from cameras aided by visual observation as the reference standards and tested the accuracy of these weather sensors in observing various weather phenomena. The results show that the data accuracy of rainfall phenomenon observations from these sensors is generally greater than 90%, which meets the needs of meteorological service; for precipitation intensity, the rainfall capture rate of these sensors is greater than 70% (rainfall intensity is greater than 0.01 mm/h), and for tracing precipitation (rainfall intensity is less than 0.01 mm/h) and mixed precipitation, the capture rate is relatively low; for low visibility phenomena, the observation accuracy is greater than 80%, which also meets the needs of meteorological service; and for other phenomena, more tests and improved algorithms are needed in future due to a relatively small number of samples.
The test procedures and result analysis of the comparative observation experiment on some present weather sensors at the Beijing Meteorological Observatory and Lushan Meteorological Service from December 2011 to June 2012 are described. There were three types of sensors tested in the 7 month experiment, each equipped with three sets provided by three manufactures. The experiment used the measurements from cameras aided by visual observation as the reference standards and tested the accuracy of these weather sensors in observing various weather phenomena. The results show that the data accuracy of rainfall phenomenon observations from these sensors is generally greater than 90%, which meets the needs of meteorological service; for precipitation intensity, the rainfall capture rate of these sensors is greater than 70% (rainfall intensity is greater than 0.01 mm/h), and for tracing precipitation (rainfall intensity is less than 0.01 mm/h) and mixed precipitation, the capture rate is relatively low; for low visibility phenomena, the observation accuracy is greater than 80%, which also meets the needs of meteorological service; and for other phenomena, more tests and improved algorithms are needed in future due to a relatively small number of samples.
2014, 42(4):624-628.
Abstract:
The distribution pattern of a single source to multi destination nodes is widely used in meteorological data sharing service. According to the operational characteristics of meteorological data sharing service, a meteorological data sharing application based on peer to peer network technology is designed and implemented, which can provide such functionalities as the production and distribution of data seeds and sharing between nodes. By establishing a simulation platform, the application of peer to peer network technology in the national meteorological broadband network (CMANet) is theoretically verified. By small scale experiments, it is proved that the peer to peer application is suitable for dealing with the scene of a single source to multi destination node transmission. It can improve the transmission efficiency of data sharing without increasing the central node resource consumption.
The distribution pattern of a single source to multi destination nodes is widely used in meteorological data sharing service. According to the operational characteristics of meteorological data sharing service, a meteorological data sharing application based on peer to peer network technology is designed and implemented, which can provide such functionalities as the production and distribution of data seeds and sharing between nodes. By establishing a simulation platform, the application of peer to peer network technology in the national meteorological broadband network (CMANet) is theoretically verified. By small scale experiments, it is proved that the peer to peer application is suitable for dealing with the scene of a single source to multi destination node transmission. It can improve the transmission efficiency of data sharing without increasing the central node resource consumption.
2014, 42(4):629-634.
Abstract:
There is a range of visual tools used in Meteorological applications, which include GrADS, NCL, CDO, IDL, etc. R language is developed by a statistician with the capability of handling large data sets. There are many packages and subroutines developed by third parties for meteorological applications.Some of them can provide powerful support for analyzing and visualizing large meteorological data sets.The NCEP data analysis tool based on R language, which can be used for statistical analysis and visualization based the meteorological data sets, shows the effort towards using R language into meteorological applications. It is possible to extend the functions of this package by applying some Bayesian analysis and parallel computing technique.
There is a range of visual tools used in Meteorological applications, which include GrADS, NCL, CDO, IDL, etc. R language is developed by a statistician with the capability of handling large data sets. There are many packages and subroutines developed by third parties for meteorological applications.Some of them can provide powerful support for analyzing and visualizing large meteorological data sets.The NCEP data analysis tool based on R language, which can be used for statistical analysis and visualization based the meteorological data sets, shows the effort towards using R language into meteorological applications. It is possible to extend the functions of this package by applying some Bayesian analysis and parallel computing technique.
2014, 42(4):635-640.
Abstract:
Based on the existing weather forecasting platform (WOSIS, MICAPS) of the Xiangxi Meteorological Service, a prefectural level public meteorological service platform is designed, which solved the “last mile” problem in meteorological service transmission. The platform uses the C/S mode, developed in the Microsoft Windows environment with VB60 SP6, and the backend database uses SQL Server 2000 The clients can be used without installing plug in. By using a variety of meteorological warning and management approaches, the platform effectively solved the problems encountered in meteorological disaster warning dissemination, improved the efficiency and quality of public weather services, and enhanced the management level of meteorological services.
Based on the existing weather forecasting platform (WOSIS, MICAPS) of the Xiangxi Meteorological Service, a prefectural level public meteorological service platform is designed, which solved the “last mile” problem in meteorological service transmission. The platform uses the C/S mode, developed in the Microsoft Windows environment with VB60 SP6, and the backend database uses SQL Server 2000 The clients can be used without installing plug in. By using a variety of meteorological warning and management approaches, the platform effectively solved the problems encountered in meteorological disaster warning dissemination, improved the efficiency and quality of public weather services, and enhanced the management level of meteorological services.
20 Implementation and Application of Private Cloud in Municipal Level Meteorological Operation Platform
2014, 42(4):641-646.
Abstract:
Based on the vSphere architecture, the Ningbo Meteorological Service deployed the meteorological private cloud which simplifies terminal managing and improves work efficiency. The private cloud supplies the standard operational environment with an innovation model for the staffs, regardless of wherever and whenever they are and whichever equipment they use. The resource utilization rate is raised by sharing the resource pool. It allows all kinds of terminals to visit the internal resources more safely, and integrates terminal management to the data center. All these help weather forecasters concentrate on key meteorological tasks.The architecture design of the private cloud is introduced, and the key technologies such as desktop virtualization, software virtualization, safety design, and optimization of user experiences involved in system deployment and application are elaborated.Application of the private cloud in the Ningbo Meteorological Service shows great potential in meteorological service.
Based on the vSphere architecture, the Ningbo Meteorological Service deployed the meteorological private cloud which simplifies terminal managing and improves work efficiency. The private cloud supplies the standard operational environment with an innovation model for the staffs, regardless of wherever and whenever they are and whichever equipment they use. The resource utilization rate is raised by sharing the resource pool. It allows all kinds of terminals to visit the internal resources more safely, and integrates terminal management to the data center. All these help weather forecasters concentrate on key meteorological tasks.The architecture design of the private cloud is introduced, and the key technologies such as desktop virtualization, software virtualization, safety design, and optimization of user experiences involved in system deployment and application are elaborated.Application of the private cloud in the Ningbo Meteorological Service shows great potential in meteorological service.
2014, 42(4):647-651.
Abstract:
An analysis is made of the typhoon monitoring with the high temporal and spatial resolution satellite data, with the application status covering the tropical cyclone structure, intensity, path, and influence of precipitation.By using high resolution satellite observations, some characteristics can be captured more clearly, including the rapid growth or dissipation of typhoon clouds, the circulation evolution at each layer, and rainfall area forecasting. Great progress has been made in forecasting capability accordingly. The future satellite development programs of China are discussed, in which the new data from FY 4 and FY 3 satellites will bring advanced sensors and new methods, with the aid of the higher frequency and spatial resolution observation, and the accuracy of typhoon intensity and track forecasting will be further improved.
An analysis is made of the typhoon monitoring with the high temporal and spatial resolution satellite data, with the application status covering the tropical cyclone structure, intensity, path, and influence of precipitation.By using high resolution satellite observations, some characteristics can be captured more clearly, including the rapid growth or dissipation of typhoon clouds, the circulation evolution at each layer, and rainfall area forecasting. Great progress has been made in forecasting capability accordingly. The future satellite development programs of China are discussed, in which the new data from FY 4 and FY 3 satellites will bring advanced sensors and new methods, with the aid of the higher frequency and spatial resolution observation, and the accuracy of typhoon intensity and track forecasting will be further improved.
2014, 42(4):652-656.
Abstract:
The Method for Object Based Diagnostic Evaluation (MODE) realize the verification of two fields by identifying objects in each filed, calculating object similarity and drawing a composite similarity between the two fields. Compared with the traditional method, which is known as a point to point method, MODE takes account of spatial location, shape size, and other factors of objects, calculates the similarity with a fuzzy logic algorithm conforming to the subjective judgment, and overcomes the shortcomings of a traditional method, such as high sensitivity to spatial locations and “double punishment.” Case studies are conducted, and the results show that MODE has evident advantages.
The Method for Object Based Diagnostic Evaluation (MODE) realize the verification of two fields by identifying objects in each filed, calculating object similarity and drawing a composite similarity between the two fields. Compared with the traditional method, which is known as a point to point method, MODE takes account of spatial location, shape size, and other factors of objects, calculates the similarity with a fuzzy logic algorithm conforming to the subjective judgment, and overcomes the shortcomings of a traditional method, such as high sensitivity to spatial locations and “double punishment.” Case studies are conducted, and the results show that MODE has evident advantages.
2014, 42(4):657-662.
Abstract:
Based on monthly average soil temperature at the depths of 0 to 40 cm and the maximum and minimum 0 cm temperature from 1961 to 2011 and monthly average soil temperature at the depth of 80 cm, 160 cm, and 320 cm from 1981 to 2011, using the statistical diagnostic methods such as linear trend analysis, moving 〖WTBX〗t〖WTBZ〗 test and power spectrum, the variation trends and variation periods of average soil temperature, climate abrupt change, and anomalous years in Xi’an are studied.The results show that under the background of global warming, the annual and seasonal soil temperature at various levels, except in the near surface layer, showed warming trends, with the heating rate being 011 to 056 ℃ per 10 years. At the levels of 0 to 20 cm and 160 cm, the average soil temperature rising rate reached its maximum in spring; at the level of 40 cm and 320 cm, the largest was in winter, and at 80 cm that is in autumn; the minimum was in summer for all layers.The annual maximum surface temperature decreased slightly, and the minimum increased obviously; there was periodic variation in the annual mean soil temperature in the layer of 0 to 40 cm with the periods being 23 years and 36 to 46 years, as well as a long term oscillation of 32 years.There appeared abrupt changes in annual mean soil temperature in 1993 or 1994There appeared anomalous high annual mean soil temperature at various levels in the early and middle 2000s, except at 160 cm (no anomalous years) and 80 cm (anomalously low). Anomalous high soil temperature appeared mainly in spring, and anomalous low mainly in summer. The correlation between soil temperature at each depth and air temperature was greater than 082, which shows that air temperature variation is the main factor leading to soil temperature variation.
Based on monthly average soil temperature at the depths of 0 to 40 cm and the maximum and minimum 0 cm temperature from 1961 to 2011 and monthly average soil temperature at the depth of 80 cm, 160 cm, and 320 cm from 1981 to 2011, using the statistical diagnostic methods such as linear trend analysis, moving 〖WTBX〗t〖WTBZ〗 test and power spectrum, the variation trends and variation periods of average soil temperature, climate abrupt change, and anomalous years in Xi’an are studied.The results show that under the background of global warming, the annual and seasonal soil temperature at various levels, except in the near surface layer, showed warming trends, with the heating rate being 011 to 056 ℃ per 10 years. At the levels of 0 to 20 cm and 160 cm, the average soil temperature rising rate reached its maximum in spring; at the level of 40 cm and 320 cm, the largest was in winter, and at 80 cm that is in autumn; the minimum was in summer for all layers.The annual maximum surface temperature decreased slightly, and the minimum increased obviously; there was periodic variation in the annual mean soil temperature in the layer of 0 to 40 cm with the periods being 23 years and 36 to 46 years, as well as a long term oscillation of 32 years.There appeared abrupt changes in annual mean soil temperature in 1993 or 1994There appeared anomalous high annual mean soil temperature at various levels in the early and middle 2000s, except at 160 cm (no anomalous years) and 80 cm (anomalously low). Anomalous high soil temperature appeared mainly in spring, and anomalous low mainly in summer. The correlation between soil temperature at each depth and air temperature was greater than 082, which shows that air temperature variation is the main factor leading to soil temperature variation.
24 Spatial and Temporal Distribution Characteristics of Summer Precipitation in Qinling and Daba Valley
2014, 42(4):663-670.
Abstract:
On the basis of the statistical diagnostic analysis method and the daily mean temperature and precipitation of 21 meteorological observation stations in the Ankang and Hanzhong from 1963 to 2012, a series of analysis is made of the spatial and temporal distribution characteristics of the annual mean temperature and precipitation, as well as seasonal mean rainfall in the Qinling and Daba valley. Results indicate that the annual mean temperature of the Qinling Daba valley significantly increased, and the change trend of the annual total precipitation of the Qinling Daba valley was not obvious; the precipitation in spring and autumn decreased, but the precipitation in summer showed an increasing trend. At the same time, using the REOF method, the summer precipitation in the Qinling Daba valley is divided into three main mode (rainfall pattern): western, eastern, and central, and the western, and the eastern types of summer precipitation were more sensitive. The analysis of a typical strong precipitation processes shows that the western and the eastern types of summer precipitation are the typical rainfall patterns and have great significance to precipitation forecasting and disaster prevention service.
On the basis of the statistical diagnostic analysis method and the daily mean temperature and precipitation of 21 meteorological observation stations in the Ankang and Hanzhong from 1963 to 2012, a series of analysis is made of the spatial and temporal distribution characteristics of the annual mean temperature and precipitation, as well as seasonal mean rainfall in the Qinling and Daba valley. Results indicate that the annual mean temperature of the Qinling Daba valley significantly increased, and the change trend of the annual total precipitation of the Qinling Daba valley was not obvious; the precipitation in spring and autumn decreased, but the precipitation in summer showed an increasing trend. At the same time, using the REOF method, the summer precipitation in the Qinling Daba valley is divided into three main mode (rainfall pattern): western, eastern, and central, and the western, and the eastern types of summer precipitation were more sensitive. The analysis of a typical strong precipitation processes shows that the western and the eastern types of summer precipitation are the typical rainfall patterns and have great significance to precipitation forecasting and disaster prevention service.
2014, 42(4):671-677.
Abstract:
By means of wind, temperature, relative humidity, visibility, and PM10 mass concentration data from the 20 m observing tower, three sand and dust storm (SDS) events observed at Datong from March 2009 to March 2010 are studied in the aspects of the variation characteristics of near surface meteorological parameters and PM10These three sand and dust storm events (i.e., dust storm, blowing sand, and floating dust) are corresponding to three typical the sand and dust weather processes.The observation data show that the wind speeds during a dust storm and blowing sand were stronger than that during floating dust.The vertical gradients of wind speeds at 1, 2, 4, 10, 20 m heights during local blowing sand cases (with the wind speed ratios being greater that of 20 m, from 041 to 079) were stronger than those in other two cases (with the wind speed ratios being greater that of 20 m, from 048 to 084).Anomalous near surface temperature variability was observed during the floating dust event, reflecting the impact of dust aerosol radiative forcing on near surface air temperature. Also, anomalous non relevant changes between relative humidity and air temperature were observed during the dust storm event, reflecting the possible impact of the dry air mass from desert regions.The averaged PM10 mass concentration levels during three sand and dust storm events were several fold higher than those during non SDS periods, and the PM10 concentration levels were: dust storm > blowing sand > floating dust.The variation of PM10 mass concentration is not solely relevant with wind speeds. In the late period of SDS events, because fine particles were blowing continuously out of the near surface air, PM10 mass concentration shows non synchronous decrease with visibility and wind speeds.
By means of wind, temperature, relative humidity, visibility, and PM10 mass concentration data from the 20 m observing tower, three sand and dust storm (SDS) events observed at Datong from March 2009 to March 2010 are studied in the aspects of the variation characteristics of near surface meteorological parameters and PM10These three sand and dust storm events (i.e., dust storm, blowing sand, and floating dust) are corresponding to three typical the sand and dust weather processes.The observation data show that the wind speeds during a dust storm and blowing sand were stronger than that during floating dust.The vertical gradients of wind speeds at 1, 2, 4, 10, 20 m heights during local blowing sand cases (with the wind speed ratios being greater that of 20 m, from 041 to 079) were stronger than those in other two cases (with the wind speed ratios being greater that of 20 m, from 048 to 084).Anomalous near surface temperature variability was observed during the floating dust event, reflecting the impact of dust aerosol radiative forcing on near surface air temperature. Also, anomalous non relevant changes between relative humidity and air temperature were observed during the dust storm event, reflecting the possible impact of the dry air mass from desert regions.The averaged PM10 mass concentration levels during three sand and dust storm events were several fold higher than those during non SDS periods, and the PM10 concentration levels were: dust storm > blowing sand > floating dust.The variation of PM10 mass concentration is not solely relevant with wind speeds. In the late period of SDS events, because fine particles were blowing continuously out of the near surface air, PM10 mass concentration shows non synchronous decrease with visibility and wind speeds.
2014, 42(4):678-681.
Abstract:
A comparison of wind data detected by an automotive wind profiler and a meteorological tower reveals no significant differences between the two types of detection approaches for the landfall typhoon Kaitak. By using the data of automotive wind profiler radar, Typhoon KAITAK is studied, and the results show that around the time before and after the typhoon eye passing through, the wind speed exhibited an M shaped variation with the maximum wind speed in the strong wind zone around the wall of the typhoon eye, the maximum 10 min mean wind speeds being 357 and 354 m/s, and the minimum being 162 m/s.The automotive wind profile radar has strong detection capability, can effectively detect the wind shear and vertical airflow shear from ground to upper levels during the landfall typhoon and help improve typhoon forecasting service in the coastal area.
A comparison of wind data detected by an automotive wind profiler and a meteorological tower reveals no significant differences between the two types of detection approaches for the landfall typhoon Kaitak. By using the data of automotive wind profiler radar, Typhoon KAITAK is studied, and the results show that around the time before and after the typhoon eye passing through, the wind speed exhibited an M shaped variation with the maximum wind speed in the strong wind zone around the wall of the typhoon eye, the maximum 10 min mean wind speeds being 357 and 354 m/s, and the minimum being 162 m/s.The automotive wind profile radar has strong detection capability, can effectively detect the wind shear and vertical airflow shear from ground to upper levels during the landfall typhoon and help improve typhoon forecasting service in the coastal area.
2014, 42(4):682-689.
Abstract:
Observation data from aircrafts equipped with DMT from 200 to 2010，surface observation stations, and satellites are analyzed to explore the macro and micro structures of cloud systems over Shanxi Province，including cloud base height，cloud thickness，cloud particle concentration，liquid water content，and effective cloud particle radius.The depth of stratiform clouds with precipitation is about 2000 m.The mean value of liquid water content of low clouds with precipitation is about 003 g·m-3, and the mean value of liquid water content of middle clouds with precipitations about 005 g·m-3. It is found that there are distinct differences between stratiform clouds with and without precipitation， by comparing their macro and micro physic parameters.To produce precipitation, the effective radius of a stratiform cloud needs to be as large as 10 μm to 14 μm.The maximum super cooled water content appears around the height of 500 m above the 0 ℃ layer for three types of clouds (Scop, Sc, and Ns). According to the size distribution of various particles, the particles with a diameter of 20 and 30 μm has the highest moisture content， making the greatest contribution to cloud liquid water concentration，and the precipitation particles are mainly composed of 20 μm and 30 μm particles.The micro physical characteristics of the cloud structures with different temperature levels are analyzed.
Observation data from aircrafts equipped with DMT from 200 to 2010，surface observation stations, and satellites are analyzed to explore the macro and micro structures of cloud systems over Shanxi Province，including cloud base height，cloud thickness，cloud particle concentration，liquid water content，and effective cloud particle radius.The depth of stratiform clouds with precipitation is about 2000 m.The mean value of liquid water content of low clouds with precipitation is about 003 g·m-3, and the mean value of liquid water content of middle clouds with precipitations about 005 g·m-3. It is found that there are distinct differences between stratiform clouds with and without precipitation， by comparing their macro and micro physic parameters.To produce precipitation, the effective radius of a stratiform cloud needs to be as large as 10 μm to 14 μm.The maximum super cooled water content appears around the height of 500 m above the 0 ℃ layer for three types of clouds (Scop, Sc, and Ns). According to the size distribution of various particles, the particles with a diameter of 20 and 30 μm has the highest moisture content， making the greatest contribution to cloud liquid water concentration，and the precipitation particles are mainly composed of 20 μm and 30 μm particles.The micro physical characteristics of the cloud structures with different temperature levels are analyzed.
2014, 42(4):690-696.
Abstract:
The isomorphism of public weather service is out of the public, policy makers, professional weather services, but the isomorphism is not be paid enough attention.Consequently, the public meteorological service is unable to meet the needs of multiple time space scales, more content, and more manifestation online Web service, leading to the difficulties in the docking of inter provincial systems and the integrating of local systems (province , county , or city level) into the national system. Taking category theory as a guide, the isomorphic model for four dimensional meteorological Web service, a system based on software reuse, is established, in an attempt to achieve the goals of “full coverage”, “uniform platform,” and “easy to promote.” Based on the specifications of the national public weather service classification, the four dimensional meteorological service containing time, space, content, and manifestation is obtained through scale quantification and, then introduction of the database adjacency model, seed fill algorithm, meteorological geographical information systems, knowledge management systems, and meteorological content management system, Google Maps software, service oriented architecture, etc., which act on the various objects within the four dimensions. Currently, the systems can provide Web online services to the public, policy makers, and professionals for 203 meteorological Web sites.
The isomorphism of public weather service is out of the public, policy makers, professional weather services, but the isomorphism is not be paid enough attention.Consequently, the public meteorological service is unable to meet the needs of multiple time space scales, more content, and more manifestation online Web service, leading to the difficulties in the docking of inter provincial systems and the integrating of local systems (province , county , or city level) into the national system. Taking category theory as a guide, the isomorphic model for four dimensional meteorological Web service, a system based on software reuse, is established, in an attempt to achieve the goals of “full coverage”, “uniform platform,” and “easy to promote.” Based on the specifications of the national public weather service classification, the four dimensional meteorological service containing time, space, content, and manifestation is obtained through scale quantification and, then introduction of the database adjacency model, seed fill algorithm, meteorological geographical information systems, knowledge management systems, and meteorological content management system, Google Maps software, service oriented architecture, etc., which act on the various objects within the four dimensions. Currently, the systems can provide Web online services to the public, policy makers, and professionals for 203 meteorological Web sites.
2014, 42(4):697-701.
Abstract:
In order to improve lightning disaster risk assessment, two quantification methods of the loss (Lx) in lightning disaster risk assessment standards are proposed. One is based on the quantification of thunderstorm days, and the other on the multiple regression analysis to quantify the loss by means of the lightning location data. The results of the regression analysis show that the 〖WTBX〗F〖WTBZ〗 statistic distribution is highly significant, and 〖WTBX〗 R〖WTBZ〗2 is over 07569 It is concluded that the second method can produce a smaller relative error comparing with the first method; the quantification based on thunderstorm days still has some inadequacies, and the quantification analysis of the loss on the basis of lightning data of Lx is more advantageous. References are provided for refined lightning disaster risk assessment.
In order to improve lightning disaster risk assessment, two quantification methods of the loss (Lx) in lightning disaster risk assessment standards are proposed. One is based on the quantification of thunderstorm days, and the other on the multiple regression analysis to quantify the loss by means of the lightning location data. The results of the regression analysis show that the 〖WTBX〗F〖WTBZ〗 statistic distribution is highly significant, and 〖WTBX〗 R〖WTBZ〗2 is over 07569 It is concluded that the second method can produce a smaller relative error comparing with the first method; the quantification based on thunderstorm days still has some inadequacies, and the quantification analysis of the loss on the basis of lightning data of Lx is more advantageous. References are provided for refined lightning disaster risk assessment.
2014, 42(4):702-706.
Abstract:
By means of lightning disaster data for nearly six years and annual thunderstorm data for 40 years, considering the background of the geographical environment and climate, the vulnerability of thunder disasters in Dalian is assessed, in which six indicators are selected, calculated by using AHP, and passed the significance test. The results show that Jinzhou has the highest risk; Wafangdian is the second, Dalian, Pulandian, and Zhuanghe are the next; Lushun has relatively low risk. It is showed that the risk assessment for regional lightning disasters is not only depended on the number of thunder storm days, but also on the economic development, the density of population, the history of disasters, as well as the weights of different indexes. The assessment analysis of regional thunder storm disasters with AHP can reduce the impact of man induced factors effectively.The results provide a basis for lightning protection and disaster reduction.
By means of lightning disaster data for nearly six years and annual thunderstorm data for 40 years, considering the background of the geographical environment and climate, the vulnerability of thunder disasters in Dalian is assessed, in which six indicators are selected, calculated by using AHP, and passed the significance test. The results show that Jinzhou has the highest risk; Wafangdian is the second, Dalian, Pulandian, and Zhuanghe are the next; Lushun has relatively low risk. It is showed that the risk assessment for regional lightning disasters is not only depended on the number of thunder storm days, but also on the economic development, the density of population, the history of disasters, as well as the weights of different indexes. The assessment analysis of regional thunder storm disasters with AHP can reduce the impact of man induced factors effectively.The results provide a basis for lightning protection and disaster reduction.
2014, 42(4):707-711.
Abstract:
By using the daily maximum power load data and meteorological data from 9 weather stations over Henan Province from 2005 to 2009, and the stepwise regression method, the summer daily maximum power load prediction models are set up.The models for the whole summer (Scheme 1) and each day of a week (Scheme 2) are established, respectively.The daily maximum power load forecasts for summer 2010 are made by the models.It is found that the daily maximum power loads in working days (Monday to Friday) show different inter annual variation features with weekends (Saturday and Sunday); the daily maximum power load is closely connected with both air temperature and hot index, and can be predicted well by the two schemes.The average prediction errors with the two models for summer 2010 are less than 3%, and the correlation coefficients are large than 09, which shows their good forecasting ability.
By using the daily maximum power load data and meteorological data from 9 weather stations over Henan Province from 2005 to 2009, and the stepwise regression method, the summer daily maximum power load prediction models are set up.The models for the whole summer (Scheme 1) and each day of a week (Scheme 2) are established, respectively.The daily maximum power load forecasts for summer 2010 are made by the models.It is found that the daily maximum power loads in working days (Monday to Friday) show different inter annual variation features with weekends (Saturday and Sunday); the daily maximum power load is closely connected with both air temperature and hot index, and can be predicted well by the two schemes.The average prediction errors with the two models for summer 2010 are less than 3%, and the correlation coefficients are large than 09, which shows their good forecasting ability.
2014, 42(4):712-718.
Abstract:
A CFD model (FloEFD) is applied to the wind field simulation around an isolated building in the Guyuan County Experiment Site.To obtain the optimal parameters of the model, a group of sensitive numerical experiments with different model parameters are carried out. The cavity length, vortex center, and the boundary location of the redevelopment area are used as the indexes to assess the outcomes.The results show that all the indexes are stable basically if the height of the computational domain is greater than 3〖WTBX〗h〖WTBZ〗 (the height of the building).The values of the indexes increase with the increasing levels of the initial mesh. All the indexes are not sensitive to the levels of local initial meshes. The vortex length before the building is more sensitive to the form of the mean wind profile than that after the building. By comparing to the observing data, the optimal parameters are: the height of computational domain being 3 times as high as building height, the level of the initial mesh being 4, the level of the local initial mesh being 4 and the form of mean the wind profile being exponential.
A CFD model (FloEFD) is applied to the wind field simulation around an isolated building in the Guyuan County Experiment Site.To obtain the optimal parameters of the model, a group of sensitive numerical experiments with different model parameters are carried out. The cavity length, vortex center, and the boundary location of the redevelopment area are used as the indexes to assess the outcomes.The results show that all the indexes are stable basically if the height of the computational domain is greater than 3〖WTBX〗h〖WTBZ〗 (the height of the building).The values of the indexes increase with the increasing levels of the initial mesh. All the indexes are not sensitive to the levels of local initial meshes. The vortex length before the building is more sensitive to the form of the mean wind profile than that after the building. By comparing to the observing data, the optimal parameters are: the height of computational domain being 3 times as high as building height, the level of the initial mesh being 4, the level of the local initial mesh being 4 and the form of mean the wind profile being exponential.
2014, 42(4):719-724.
Abstract:
The basic characteristics and different background characteristics of wet heat high temperature and dry heat high temperature weather in Jinshan from 1981 to 2010 are studied.The impacts of high temperature on the people〖DK〗’s life and work are studied with the human body comfort index.The results indicate: (1) The dry heat high temperature weather is controlled by strong subtropical high at upper levels, and the surface is usually in the clear area before or after a high pressure system; the wet heat high temperature weather is controlled by the less strong subtropical high, and the surface is mostly at the bottom of a low pressure, leading to invasion of moisture. (2) During the years of dry heat high temperature, the West Pacific high is found to be more westward and strengthened, and the South Asia high lies more easterly and northerly, with stronger summer monsoon and stronger descending motion. (3) During the years of wet heat high temperature, ascending motion exists below 900 hPa in latitudinal direction, which is favorable to the development of convective activities.Two types of high temperature show the characteristic of persistent discomfort all day long. (4) During the daytime, the wet heat high temperature has longer duration of extreme high temperature and greater body discomfortibility, while during the nighttime the dry heat high temperature weather has greater body discomfort.
The basic characteristics and different background characteristics of wet heat high temperature and dry heat high temperature weather in Jinshan from 1981 to 2010 are studied.The impacts of high temperature on the people〖DK〗’s life and work are studied with the human body comfort index.The results indicate: (1) The dry heat high temperature weather is controlled by strong subtropical high at upper levels, and the surface is usually in the clear area before or after a high pressure system; the wet heat high temperature weather is controlled by the less strong subtropical high, and the surface is mostly at the bottom of a low pressure, leading to invasion of moisture. (2) During the years of dry heat high temperature, the West Pacific high is found to be more westward and strengthened, and the South Asia high lies more easterly and northerly, with stronger summer monsoon and stronger descending motion. (3) During the years of wet heat high temperature, ascending motion exists below 900 hPa in latitudinal direction, which is favorable to the development of convective activities.Two types of high temperature show the characteristic of persistent discomfort all day long. (4) During the daytime, the wet heat high temperature has longer duration of extreme high temperature and greater body discomfortibility, while during the nighttime the dry heat high temperature weather has greater body discomfort.
2014, 42(4):725-730.
Abstract:
By means of the statistical method, using the data of air temperature, sunshine duration, and precipitation from 1962 to 2010 of 96 weather stations and the data of rape growth from 1991 to 2010 of 5 agrometeorological stations in Hunan Province, the spatial distributions and inter annual variations of agrometeorological elements closely correlated to different growth stages of rape are analyzed.Results show that the whole growth period of rape has no significant differences between regions, but the accumulated temperature of ≥0 ℃ during the rape growth period has obvious regional difference.The main influencing meteorological factors during the rape growth period are air temperature and sunshine duration, which vary at different growth stages.The climate resources are unevenly distributed spatially, and the inter annual variation of climate resources differs at different growth stages.The accumulated temperatures before wintering and pod development periods trend to increase; the numbers of days of 〖WTBX〗T 〖WTBZ〗≤0 ℃ or 〖WTBX〗T 〖WTBZ〗≤－3 ℃in the wintering period trend to decrease; the sunshine duration during the stem elongation period trends to decrease; the sunshine duration during the flowering and pod development periods show a trend of increase. Overall, the climatic resources and variation trends during the rapes growth period are advantageous to rape planting.
By means of the statistical method, using the data of air temperature, sunshine duration, and precipitation from 1962 to 2010 of 96 weather stations and the data of rape growth from 1991 to 2010 of 5 agrometeorological stations in Hunan Province, the spatial distributions and inter annual variations of agrometeorological elements closely correlated to different growth stages of rape are analyzed.Results show that the whole growth period of rape has no significant differences between regions, but the accumulated temperature of ≥0 ℃ during the rape growth period has obvious regional difference.The main influencing meteorological factors during the rape growth period are air temperature and sunshine duration, which vary at different growth stages.The climate resources are unevenly distributed spatially, and the inter annual variation of climate resources differs at different growth stages.The accumulated temperatures before wintering and pod development periods trend to increase; the numbers of days of 〖WTBX〗T 〖WTBZ〗≤0 ℃ or 〖WTBX〗T 〖WTBZ〗≤－3 ℃in the wintering period trend to decrease; the sunshine duration during the stem elongation period trends to decrease; the sunshine duration during the flowering and pod development periods show a trend of increase. Overall, the climatic resources and variation trends during the rapes growth period are advantageous to rape planting.
External LinksChina Meteorological AdministrationCMA Meteorological Observation CentreChinese Academy of Meteorological SciencesBeijing Meteorological ServiceNational Satellite Meteorological Center
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Supported by:Beijing E-Tiller Technology Development Co., Ltd.
Supported by:Beijing E-Tiller Technology Development Co., Ltd.