Volume 44,Issue 3,2016 Table of Contents
2016, 44(3):347-353.
Abstract:
Using the undisturbed soil samples in soil moisture automatic stations, contrast observation was conducted between manual weighting soil moisture data and automatic soil moisture data at the same time. A serials of manual and automatic measurement data is obtained. The manual weighting soil moisture data are used as standards to calibrate the different depth sensors. Due to the use of undisturbed soil samples, the texture, density, particles, and tightness of the soil samples remain unchanged, the correction equation is more reasonable and accurate. This method can also correct the unreasonable field calibration equation induced by insufficient samples.
Using the undisturbed soil samples in soil moisture automatic stations, contrast observation was conducted between manual weighting soil moisture data and automatic soil moisture data at the same time. A serials of manual and automatic measurement data is obtained. The manual weighting soil moisture data are used as standards to calibrate the different depth sensors. Due to the use of undisturbed soil samples, the texture, density, particles, and tightness of the soil samples remain unchanged, the correction equation is more reasonable and accurate. This method can also correct the unreasonable field calibration equation induced by insufficient samples.
2016, 44(3):354-357.
Abstract:
Base on the analysis of the hourly ground surface temperature differences between new automatic weather station and old one in 7 national weather stations of Shanxi in 2014, it is found that the existing observation methods and equipment make large errors of surface temperature. The data consistent rate is only 93.6 7%, while the outoftolerance rate reaches 35.70%, and errors are more evident during the daytime. Through an indepth analysis on the factors that affect the ground temperature observations, combined with the test results, it is concluded that the solar radiation intensity has little effect on the ground temperature observation errors, and the observation field soil, observation method, sensors, and equipment maintenance have a greater impact on errors. Therefore, it is suggested that the infrared remote sensing method should be used to replace the existing observation method of platinum resistance buried directly.
Base on the analysis of the hourly ground surface temperature differences between new automatic weather station and old one in 7 national weather stations of Shanxi in 2014, it is found that the existing observation methods and equipment make large errors of surface temperature. The data consistent rate is only 93.6 7%, while the outoftolerance rate reaches 35.70%, and errors are more evident during the daytime. Through an indepth analysis on the factors that affect the ground temperature observations, combined with the test results, it is concluded that the solar radiation intensity has little effect on the ground temperature observation errors, and the observation field soil, observation method, sensors, and equipment maintenance have a greater impact on errors. Therefore, it is suggested that the infrared remote sensing method should be used to replace the existing observation method of platinum resistance buried directly.
2016, 44(3):358-362.
Abstract:
At present， the provinciallevel meteorological WAN of Hubei is through one 〖JP2〗telecommunications〖JP〗 line to realize communication between provincial and municipal levels，and uses a dialup VPN line to make backup. It is not enough to guarantee the reliability of data transmission. So a special line is designed to realize doubleline backup. At the same time， a switch is added for provincial network interconnection, to replace the router for municipal network interconnection.The data are divided into two classes: convention data and video data.Different transmission modes are defined. Convention data adopt the OSPF dynamic routing method for transmission, and video data adopt the static routing BFD linkage for transmission, to guarantee the 4 Mb/s bandwidth by QoS. It can realize reliable and more reasonable data transmission between provincial and municipal levels.
At present， the provinciallevel meteorological WAN of Hubei is through one 〖JP2〗telecommunications〖JP〗 line to realize communication between provincial and municipal levels，and uses a dialup VPN line to make backup. It is not enough to guarantee the reliability of data transmission. So a special line is designed to realize doubleline backup. At the same time， a switch is added for provincial network interconnection, to replace the router for municipal network interconnection.The data are divided into two classes: convention data and video data.Different transmission modes are defined. Convention data adopt the OSPF dynamic routing method for transmission, and video data adopt the static routing BFD linkage for transmission, to guarantee the 4 Mb/s bandwidth by QoS. It can realize reliable and more reasonable data transmission between provincial and municipal levels.
2016, 44(3):363-368.
Abstract:
An operational intensive platform for prefectural/countylevel public meteorological service is developed. The software operation of the countylevel stations is simplified. Meteorological service products run through the whole software process, so the management and operation of meteorological service products are standardized. The platform includes meteorological service discovery engine, meteorological data realtime computing engine, meteorological information visualization engine, production templates engine for meteorological service products, and comprehensive tool engine, so the production of meteorological service products is more intelligent. Based on the service task scheduling model, oneclick release of meteorological service products is realized with multithread, multiprocess, and load balancing. The platform has solved the main difficulties in meteorological service product production and release process, and improved the capability and level of public meteorological service.
An operational intensive platform for prefectural/countylevel public meteorological service is developed. The software operation of the countylevel stations is simplified. Meteorological service products run through the whole software process, so the management and operation of meteorological service products are standardized. The platform includes meteorological service discovery engine, meteorological data realtime computing engine, meteorological information visualization engine, production templates engine for meteorological service products, and comprehensive tool engine, so the production of meteorological service products is more intelligent. Based on the service task scheduling model, oneclick release of meteorological service products is realized with multithread, multiprocess, and load balancing. The platform has solved the main difficulties in meteorological service product production and release process, and improved the capability and level of public meteorological service.
2016, 44(3):369-373.
Abstract:
To reduce the meteorological data statistic workload and enhance the abilities of meteorological monitoring and forecasting service, the Kunming Meteorological Information Query System is designed with the B/S structure system for weather forecasters in prefecturallevel meteorological observatories, by using the RIA and WebGIS technology of Silverlight. This system achieved the realtime display of geographic maps and the surfing of observational data, refined forecast data, and Doppler radar echo data efficiently. The application indicates that these statistic meteorological information can be used in weather forecasting, meteorological monitoring，the shortterm forecasting, nowcasting, and disaster weather warning meteorological operations visually, immediately and directly from the system, with which scientific and efficient technology support can be supplied.
To reduce the meteorological data statistic workload and enhance the abilities of meteorological monitoring and forecasting service, the Kunming Meteorological Information Query System is designed with the B/S structure system for weather forecasters in prefecturallevel meteorological observatories, by using the RIA and WebGIS technology of Silverlight. This system achieved the realtime display of geographic maps and the surfing of observational data, refined forecast data, and Doppler radar echo data efficiently. The application indicates that these statistic meteorological information can be used in weather forecasting, meteorological monitoring，the shortterm forecasting, nowcasting, and disaster weather warning meteorological operations visually, immediately and directly from the system, with which scientific and efficient technology support can be supplied.
2016, 44(3):374-380.
Abstract:
A traffic meteorological service system based on mobile internet is designed. Through combining a series of refined gridded data, the system provides a series of personalized traffic meteorological services based on locations, such as voice navigation services for highimpact weather, meteorological knowledge extraction, integrated Web publishing based on WebGIS, and intelligent navigation based on the refined gridded data. To ensure high bearing capacity and rapid response characteristics, the refined gridded data are transferred in the binary model, and the tiled map resources are generated in the distributed computing environment. The whole process of data processing is managed by the memory management mechanism of Memcached. This system has already been applied as an independent module in the SmartWeather mobile client designed by the Zhejiang Provincial Meteorological Service.
A traffic meteorological service system based on mobile internet is designed. Through combining a series of refined gridded data, the system provides a series of personalized traffic meteorological services based on locations, such as voice navigation services for highimpact weather, meteorological knowledge extraction, integrated Web publishing based on WebGIS, and intelligent navigation based on the refined gridded data. To ensure high bearing capacity and rapid response characteristics, the refined gridded data are transferred in the binary model, and the tiled map resources are generated in the distributed computing environment. The whole process of data processing is managed by the memory management mechanism of Memcached. This system has already been applied as an independent module in the SmartWeather mobile client designed by the Zhejiang Provincial Meteorological Service.
2016, 44(3):381-386.
Abstract:
In order to improve operational soil moisture observation, a soil moisture monitoring and analysis system is developed, which realizes the united assessment and treatment of data with the equipment from different factories. Based on the requirements of agricultural drought monitoring service, the functions of data quality control, monitoring and early warning, and data application are added in the system. The establishment of the system has a practical significance to the improvement of data quality and the technical insurance in equipment. Through the local area network or Internet, the personnel in basic stations can understand and analyze in real time soil moisture changes in the local or provincial areas, which provides a powerful and reliable service means for agricultural production. The trial application indicates that the system runs steadily and has broad application prospects.
In order to improve operational soil moisture observation, a soil moisture monitoring and analysis system is developed, which realizes the united assessment and treatment of data with the equipment from different factories. Based on the requirements of agricultural drought monitoring service, the functions of data quality control, monitoring and early warning, and data application are added in the system. The establishment of the system has a practical significance to the improvement of data quality and the technical insurance in equipment. Through the local area network or Internet, the personnel in basic stations can understand and analyze in real time soil moisture changes in the local or provincial areas, which provides a powerful and reliable service means for agricultural production. The trial application indicates that the system runs steadily and has broad application prospects.
Yao Junmeng
,
Shan Jiusheng
,
Yu Donghui
,
Cai Zhe
,
Guo Ruige
,
Fang Chaoyang
,
Liu Wenying
,
Yang Aiping
2016, 44(3):387-391.
Abstract:
The straightthrough agrometeorological service platform is developed based on the WeChat public account of “Jiangxi MicroAgriculture.” There are three blocks: weather service, agricultural services, and interaction, including functions such as weather forecast, meteorological disaster warning, weather radar, satellite images and pest intelligence, farming guide, rural policy, agricultural subsidies, and science training. The platform is run by two departments of meteorology and agriculture, and provides featured, Informationrich, and professional agricultural services. The management system is built for administrators of all levels to manage users, push messages, maintain products and communicate with users. Using the management system can significantly reduce operational workload and achieve the integration of provincial, city, and county services.
The straightthrough agrometeorological service platform is developed based on the WeChat public account of “Jiangxi MicroAgriculture.” There are three blocks: weather service, agricultural services, and interaction, including functions such as weather forecast, meteorological disaster warning, weather radar, satellite images and pest intelligence, farming guide, rural policy, agricultural subsidies, and science training. The platform is run by two departments of meteorology and agriculture, and provides featured, Informationrich, and professional agricultural services. The management system is built for administrators of all levels to manage users, push messages, maintain products and communicate with users. Using the management system can significantly reduce operational workload and achieve the integration of provincial, city, and county services.
2016, 44(3):392-399.
Abstract:
Because of forecasting deviation of severe precipitation model with observation, TS verification cannot characterize well the capability of severe precipitation forecasting models. The verification method about precipitation area is formulated, and based on it and the models of EnWRF, WRFRUC, T639, and ECthin forecast, 16 severe precipitation area forecasts from May to September in 2014 and 2015 in Shandong are verified with observation. The results show that except local severe convective weather caused by the motion of subtropical high, the other processes all have referential meaning. EnWRF and ECthin are the best, with the forecast of precipitation area highly similar to observation, and the two model are complementary. In most cases, the model forecast for precipitation is less than the observation. ECthin and EnWRF have the least number of missing reports and most accurate cases, and T639 model is the next, whereas WRFRUC model has the most number of missing reports and lowest accuracy. For the forecasts with deviation, the directions of model forecast precipitation area are generaly more west or north than normal comparing with observation.
Because of forecasting deviation of severe precipitation model with observation, TS verification cannot characterize well the capability of severe precipitation forecasting models. The verification method about precipitation area is formulated, and based on it and the models of EnWRF, WRFRUC, T639, and ECthin forecast, 16 severe precipitation area forecasts from May to September in 2014 and 2015 in Shandong are verified with observation. The results show that except local severe convective weather caused by the motion of subtropical high, the other processes all have referential meaning. EnWRF and ECthin are the best, with the forecast of precipitation area highly similar to observation, and the two model are complementary. In most cases, the model forecast for precipitation is less than the observation. ECthin and EnWRF have the least number of missing reports and most accurate cases, and T639 model is the next, whereas WRFRUC model has the most number of missing reports and lowest accuracy. For the forecasts with deviation, the directions of model forecast precipitation area are generaly more west or north than normal comparing with observation.
2016, 44(3):400-407.
Abstract:
Using the monthly precipitation data of stations over the Haihe basin and NCEP/NCAR reanalysis data, the largescale relation between summer precipitation over the Haihe basin and Northern Hemisphere circulation anomalies from 1981 to 2013 is examined. The singular value decomposition (SVD) analysis is applied to reveal the connection between two fields. Results show that the leading two SVDcoupled modes explain more than half of the squared covariance between those two fields. It is found that tropical 500hPa height anomalies affect the precipitation anomalies of the whole basin, and the subtropical 500 height anomolies has significant effects on the summer precipitation anomalies over the southeast part of the basin. Tropical and subtropical circulation indices are then defined, according to the spatial patterns of the leading two SVD modes, to analyze possible mechanisms of the mentioned coupling connections. Composite analysis with respect to the above indices suggests that anomalous subtropical westerly jet and water vapor transports are associated with the anomalous indices. In weak tropical index years and especially strong subtropical index years, there can be seen a stronger and northward subtropical westerly jet, as well as significant anomalous water vapor flux convergence accumulation near the basin region. Especially, anomalous water vapor transports associated with the two anomalous indices are from different origins.
Using the monthly precipitation data of stations over the Haihe basin and NCEP/NCAR reanalysis data, the largescale relation between summer precipitation over the Haihe basin and Northern Hemisphere circulation anomalies from 1981 to 2013 is examined. The singular value decomposition (SVD) analysis is applied to reveal the connection between two fields. Results show that the leading two SVDcoupled modes explain more than half of the squared covariance between those two fields. It is found that tropical 500hPa height anomalies affect the precipitation anomalies of the whole basin, and the subtropical 500 height anomolies has significant effects on the summer precipitation anomalies over the southeast part of the basin. Tropical and subtropical circulation indices are then defined, according to the spatial patterns of the leading two SVD modes, to analyze possible mechanisms of the mentioned coupling connections. Composite analysis with respect to the above indices suggests that anomalous subtropical westerly jet and water vapor transports are associated with the anomalous indices. In weak tropical index years and especially strong subtropical index years, there can be seen a stronger and northward subtropical westerly jet, as well as significant anomalous water vapor flux convergence accumulation near the basin region. Especially, anomalous water vapor transports associated with the two anomalous indices are from different origins.
2016, 44(3):408-415.
Abstract:
Based on the Sichuan rainstorm hazard and economic loss survey from 1984 to 2010, the daily precipitation data, and NCEP reanalysis data from June to September, 1981 to 2010 in Sichuan, the characteristics of economic loss induced by rainstorm hazard for nearly 30 years are studied and the multiscale circulation background in Sichuan rainstorm hazard is obtained. The results show that rainstorminduced economic losses from 2000 to 2010 over the previous 10 years increased by 80.6%, and the occurrence frequency of rainstorm hazard increased by 38%. The characteristics of rainstorm circulation background form June to September are: South Asia High is stronger in the year of “flooding in west and drought in east” than in the year of “flooding in east and drought in west”; the 586 line of Western Pacific Subtropical High is located in the south of Sichuan and Chongqing; in flood years, Subtropical High has significantly quasibiweekly oscillation cycle from the beginning of July, and the volatility of westerly circulation index is greater. In the middle and upper troposphere at high latitudes, the East Asia atmospheric circulation has a 14day LFO (Low Frequency Oscillation); the Plateau vortex has about 14day turbulence cycle; the southwest flow at low latitudes repeatedly is delivered to high latitudes, and the Bay of Bengal vapor flux is stronger than normal; and the vapor passage into the Sichuan region is unobstructed.
Based on the Sichuan rainstorm hazard and economic loss survey from 1984 to 2010, the daily precipitation data, and NCEP reanalysis data from June to September, 1981 to 2010 in Sichuan, the characteristics of economic loss induced by rainstorm hazard for nearly 30 years are studied and the multiscale circulation background in Sichuan rainstorm hazard is obtained. The results show that rainstorminduced economic losses from 2000 to 2010 over the previous 10 years increased by 80.6%, and the occurrence frequency of rainstorm hazard increased by 38%. The characteristics of rainstorm circulation background form June to September are: South Asia High is stronger in the year of “flooding in west and drought in east” than in the year of “flooding in east and drought in west”; the 586 line of Western Pacific Subtropical High is located in the south of Sichuan and Chongqing; in flood years, Subtropical High has significantly quasibiweekly oscillation cycle from the beginning of July, and the volatility of westerly circulation index is greater. In the middle and upper troposphere at high latitudes, the East Asia atmospheric circulation has a 14day LFO (Low Frequency Oscillation); the Plateau vortex has about 14day turbulence cycle; the southwest flow at low latitudes repeatedly is delivered to high latitudes, and the Bay of Bengal vapor flux is stronger than normal; and the vapor passage into the Sichuan region is unobstructed.
2016, 44(3):416-422.
Abstract:
The variation characteristics of visibility in the Bohai Rim region and the main contributors for different levels of visibility are examined statistically, using the daily visibility observations from 365 meteorological stations from 1980 to 2012. The results indicate that the region is mainly characterized by higher visibility in spring and autumn and lower in winter. During the period of 1980 to 2012, the maximum decline rate in annually averaged visibility is detected in the Taihang Mountains and the windward slope of the Yanshan Mountains, where are characterized by lower average visibility. Overall, water droplets are the primary contributor to visibility of less than 1 km in the Bohai Rim region, but the contribution of PM2.5 trends to increase with visibility, in the range of 1 km to 10 km visibility. Additionally, the spatial differences in the impact of water droplet and PM10、PM2.5 for different levels of visibility are addressed.
The variation characteristics of visibility in the Bohai Rim region and the main contributors for different levels of visibility are examined statistically, using the daily visibility observations from 365 meteorological stations from 1980 to 2012. The results indicate that the region is mainly characterized by higher visibility in spring and autumn and lower in winter. During the period of 1980 to 2012, the maximum decline rate in annually averaged visibility is detected in the Taihang Mountains and the windward slope of the Yanshan Mountains, where are characterized by lower average visibility. Overall, water droplets are the primary contributor to visibility of less than 1 km in the Bohai Rim region, but the contribution of PM2.5 trends to increase with visibility, in the range of 1 km to 10 km visibility. Additionally, the spatial differences in the impact of water droplet and PM10、PM2.5 for different levels of visibility are addressed.
2016, 44(3):423-429.
Abstract:
Based on the hourly and minutely precipitation data of 1970 to 2000 from 2008 to 2014, the spatialtemporal distribution characteristics of shortperiod heavy precipitation from May to September in Baoxing are analyzed. The results indicate that: shortperiod heavy precipitation in Baoxing occurs in July and August mostly; owing to complex topography, different altitude and location, the intensity of shortperiod heavy precipitation varies greatly; the maximum rainfall intensity is at the altitude of 140 to 1500 meters and the longest rain duration at the altitude about 2580 meters, which are apt to lead to geological disasters such as debris flow; below the altitude of 1300 meters, the higher the altitude is, the longer the development of the mesoγ scale system sustains and the stronger the precipitation intensity is, and above the altitude of 1300 meters, vice versa.
Based on the hourly and minutely precipitation data of 1970 to 2000 from 2008 to 2014, the spatialtemporal distribution characteristics of shortperiod heavy precipitation from May to September in Baoxing are analyzed. The results indicate that: shortperiod heavy precipitation in Baoxing occurs in July and August mostly; owing to complex topography, different altitude and location, the intensity of shortperiod heavy precipitation varies greatly; the maximum rainfall intensity is at the altitude of 140 to 1500 meters and the longest rain duration at the altitude about 2580 meters, which are apt to lead to geological disasters such as debris flow; below the altitude of 1300 meters, the higher the altitude is, the longer the development of the mesoγ scale system sustains and the stronger the precipitation intensity is, and above the altitude of 1300 meters, vice versa.
2016, 44(3):430-438.
Abstract:
Using the data of conventional observation and NCEP/GFS (0.5°×0.5°), in combination with objective analysis of EC finemesh (0.25°×0.25°) data and the wind profile radar data of Urumqi, the mesoscale causes and the evolution characteristics of the extreme blizzard on 8 December 2014 in Urumqi are analyzed. The results show that under the background of superposing and maintaining of the northwestern lowlevel jet and the southern west highlevel jet, the blizzard was produced by the interaction of meso and smallscale systems such as the shear and convergence system of the wind from 700 hPa to the surface, surface cold front, orographic uplift, and so on. There were significant inversion, wind disturbance, and the southeast lowlevel jet in the surface layer over Urumqi before the snow. The warm dry lid played a role of storing and accumulating energy. While snowing, the cold and warm air met in front of the mountains, prompting the increase of baroclinic instability. The northwest lowlevel jet dynamically worked as a dynamic trigger in the snowstorm. The surface orographic uplift helps maintain the strongly ascending motion and mesoscaleβ secondary circulations. Also, the maintenance of the powerful lowlevel water vapor convergence provided sufficient water vapor for the blizzard. Meanwhile, the special orography of Urumqi obviously contributed to the blizzard growth. On the wind profile radar, there was a clear shear of the southeast and northwest winds in the lowlevel layer before and after the snow, the sounding height reached the highest, and the stronger northerly lowlevel wind corresponded to the high value of C2n when snowing heavily. For the shortterm forecast of the blizzard, the horizontal wind and C2n have great reference value.
Using the data of conventional observation and NCEP/GFS (0.5°×0.5°), in combination with objective analysis of EC finemesh (0.25°×0.25°) data and the wind profile radar data of Urumqi, the mesoscale causes and the evolution characteristics of the extreme blizzard on 8 December 2014 in Urumqi are analyzed. The results show that under the background of superposing and maintaining of the northwestern lowlevel jet and the southern west highlevel jet, the blizzard was produced by the interaction of meso and smallscale systems such as the shear and convergence system of the wind from 700 hPa to the surface, surface cold front, orographic uplift, and so on. There were significant inversion, wind disturbance, and the southeast lowlevel jet in the surface layer over Urumqi before the snow. The warm dry lid played a role of storing and accumulating energy. While snowing, the cold and warm air met in front of the mountains, prompting the increase of baroclinic instability. The northwest lowlevel jet dynamically worked as a dynamic trigger in the snowstorm. The surface orographic uplift helps maintain the strongly ascending motion and mesoscaleβ secondary circulations. Also, the maintenance of the powerful lowlevel water vapor convergence provided sufficient water vapor for the blizzard. Meanwhile, the special orography of Urumqi obviously contributed to the blizzard growth. On the wind profile radar, there was a clear shear of the southeast and northwest winds in the lowlevel layer before and after the snow, the sounding height reached the highest, and the stronger northerly lowlevel wind corresponded to the high value of C2n when snowing heavily. For the shortterm forecast of the blizzard, the horizontal wind and C2n have great reference value.
2016, 44(3):439-446.
Abstract:
The formative causes of a shorttime convective rainstorm on 19 July 2012 at Atux in Xinjiang is analyzed based on multiple data including surface, radiosonde, Doppler weather radar, 6h 1°×1° NCEP reanalysis data, and automatic station data. The results show: (1) The weather process was triggered by the upward movement and instability energy release of a mesoscale cyclone at low levels on the background of a vortex located over the south Xinjiang. (2) The invasion of cold air was one of important reasons for the convective development, and the smallscale synoptic systems in surface also contributed to instability energy release. The basic convective conditions such as vorticity and divergence field configuration, vertical speed, lowlevel easterly jet, and strong unstable energy were fulfilled and enhanced by the severe vertical wind shear. (3) The corrected sounding data of Kasha was more indicative of severe convection potential forecast and still need further verification. (4) According to Doppler radar data, the strong echo reflectivity, severe vertical wind shear, richer vertical integrated liquid, and higher echo top have close relation with the development and precipitation of the weather process.
The formative causes of a shorttime convective rainstorm on 19 July 2012 at Atux in Xinjiang is analyzed based on multiple data including surface, radiosonde, Doppler weather radar, 6h 1°×1° NCEP reanalysis data, and automatic station data. The results show: (1) The weather process was triggered by the upward movement and instability energy release of a mesoscale cyclone at low levels on the background of a vortex located over the south Xinjiang. (2) The invasion of cold air was one of important reasons for the convective development, and the smallscale synoptic systems in surface also contributed to instability energy release. The basic convective conditions such as vorticity and divergence field configuration, vertical speed, lowlevel easterly jet, and strong unstable energy were fulfilled and enhanced by the severe vertical wind shear. (3) The corrected sounding data of Kasha was more indicative of severe convection potential forecast and still need further verification. (4) According to Doppler radar data, the strong echo reflectivity, severe vertical wind shear, richer vertical integrated liquid, and higher echo top have close relation with the development and precipitation of the weather process.
2016, 44(3):447-452.
Abstract:
Based on the monitoring data of meteorological stations, highway meteorological monitoring data, and the highway traffic information in Hebei Province from April 2010 to March 2013, the impacts of severe weather on highway traffic in Hebei province are analyzed. The results show: (1) 383% of highway traffic blocking events are caused by meteorological factors, among which the first factor is fogs and the second is snow; (2) the monthly change characteristic of traffic blocking resulting from fogs is most significant, and the occurrence frequencies in autumn and winter are obviously greater than those in spring and summer, and the influencing time is significantly longer in autumn and winter; (3) the annual average numbers of traffic blocking days resulting from fogs in the southeastern plains are greater than those in the western and northern mountain areas. Snow and ice are contrary; (4) through the analysis of a continual fog and haze process impacting highway traffic, a fog warning model of highway is preliminarily established, and some countermeasures of traffic meteorological service under the severs weather are put forward, which provides a reference for improving highway capacity in severe weather.
Based on the monitoring data of meteorological stations, highway meteorological monitoring data, and the highway traffic information in Hebei Province from April 2010 to March 2013, the impacts of severe weather on highway traffic in Hebei province are analyzed. The results show: (1) 383% of highway traffic blocking events are caused by meteorological factors, among which the first factor is fogs and the second is snow; (2) the monthly change characteristic of traffic blocking resulting from fogs is most significant, and the occurrence frequencies in autumn and winter are obviously greater than those in spring and summer, and the influencing time is significantly longer in autumn and winter; (3) the annual average numbers of traffic blocking days resulting from fogs in the southeastern plains are greater than those in the western and northern mountain areas. Snow and ice are contrary; (4) through the analysis of a continual fog and haze process impacting highway traffic, a fog warning model of highway is preliminarily established, and some countermeasures of traffic meteorological service under the severs weather are put forward, which provides a reference for improving highway capacity in severe weather.
2016, 44(3):453-457.
Abstract:
Based on the statistical analysis of the data from blind water sample assessment in past 5 years conducted by the China Meteorological Administration that Anhui Provincial meteorological acid rain observatories participated in, the main reason for the conductivity decline of blind water samples in acid rain observation stations of Anhui Province in 2014 is the change of instrument electrodes. It is concluded that the Model990 AcidRain Gauge presents obviously larger systematic error in measuring the K with the platinum black electrode. However, the physical shape of the lighttype conductive electrodes remains the same, and its cell constant is almost invariant. Thus, they can be used for a long term via demarcating with standard solution. In order to improve the accuracy of conductivity Kvalue measurement, it is suggested that stations should use the standard solution with a conductivity of 84.3 or 146.5 μS〖DK〗·cm-1 which is commercially available to demarcate the device electrodes regularly every year. In addition, recommendations are proposed for the security and verification system of acid rain detection equipment.
Based on the statistical analysis of the data from blind water sample assessment in past 5 years conducted by the China Meteorological Administration that Anhui Provincial meteorological acid rain observatories participated in, the main reason for the conductivity decline of blind water samples in acid rain observation stations of Anhui Province in 2014 is the change of instrument electrodes. It is concluded that the Model990 AcidRain Gauge presents obviously larger systematic error in measuring the K with the platinum black electrode. However, the physical shape of the lighttype conductive electrodes remains the same, and its cell constant is almost invariant. Thus, they can be used for a long term via demarcating with standard solution. In order to improve the accuracy of conductivity Kvalue measurement, it is suggested that stations should use the standard solution with a conductivity of 84.3 or 146.5 μS〖DK〗·cm-1 which is commercially available to demarcate the device electrodes regularly every year. In addition, recommendations are proposed for the security and verification system of acid rain detection equipment.
2016, 44(3):458-462.
Abstract:
Based on the hourly PM2.5 concentration data of 10 environmental monitoring stations of Guiyang in 2013 and 2014, the pollution characteristics of PM2.5in 2013 and 2014 are described. In combination with the comparative analysis of Guiyang hourly precipitation data, the change features of precipitation and particulate pollution are discussed. The results show: The annual mean value of PM2.5 was about 33 to 55 μg/m3; the monthly pollution concentration values were high in autumn, winter, and early spring, but low in summer. The daily variation of PM2.5 concentrations showed the typical structure with double peaks, and the value was high in morning and evening. When there is rainfall, average concentration is nearly 20% lower than that without precipitation annually. The PM2.5concentrations in rainy days were lower obviously than those without rain. In the rainy days, the concentrations of PM2.5 were reduced obviously especially during night and morning session, which was associated with the precipitation characteristics of Guiyang. Compared with the precipitation less than 1 mm, the removal and inhibition effect of precipitation greater than 1 mm was more remarkable.
Based on the hourly PM2.5 concentration data of 10 environmental monitoring stations of Guiyang in 2013 and 2014, the pollution characteristics of PM2.5in 2013 and 2014 are described. In combination with the comparative analysis of Guiyang hourly precipitation data, the change features of precipitation and particulate pollution are discussed. The results show: The annual mean value of PM2.5 was about 33 to 55 μg/m3; the monthly pollution concentration values were high in autumn, winter, and early spring, but low in summer. The daily variation of PM2.5 concentrations showed the typical structure with double peaks, and the value was high in morning and evening. When there is rainfall, average concentration is nearly 20% lower than that without precipitation annually. The PM2.5concentrations in rainy days were lower obviously than those without rain. In the rainy days, the concentrations of PM2.5 were reduced obviously especially during night and morning session, which was associated with the precipitation characteristics of Guiyang. Compared with the precipitation less than 1 mm, the removal and inhibition effect of precipitation greater than 1 mm was more remarkable.
2016, 44(3):463-467.
Abstract:
Based on the daily mortality data of residents in Wuhan from 1 January 2004 to 31 December 2008, the meteorological indicators and atmospheric pollution index of the same period, the distributed lag nonlinear model (DLNM) is used to assess the effects of daily mean temperature on deaths (caused by cardiovascular and respiratory), adjusted for both secular，seasonal trends and other confounders.The results indicate that the effect of Wuhan average daily temperature on the two diseases has a Jshaped curve. The cold effect on cardiovascular and respiratory has a delay of l to 4 days and persists for 8 to 20 days. The hot effect appeared acute and the highest at the first day for both cardiovascular and respiratory，but lasts for 2 days and followed by mortality displacement. It can be seen that in Wuhan both low and high temperature increase the risk of cardiovascular and respiratory mortality with delayed effects. Cold effects seem to last longer than heat effects.
Based on the daily mortality data of residents in Wuhan from 1 January 2004 to 31 December 2008, the meteorological indicators and atmospheric pollution index of the same period, the distributed lag nonlinear model (DLNM) is used to assess the effects of daily mean temperature on deaths (caused by cardiovascular and respiratory), adjusted for both secular，seasonal trends and other confounders.The results indicate that the effect of Wuhan average daily temperature on the two diseases has a Jshaped curve. The cold effect on cardiovascular and respiratory has a delay of l to 4 days and persists for 8 to 20 days. The hot effect appeared acute and the highest at the first day for both cardiovascular and respiratory，but lasts for 2 days and followed by mortality displacement. It can be seen that in Wuhan both low and high temperature increase the risk of cardiovascular and respiratory mortality with delayed effects. Cold effects seem to last longer than heat effects.
2016, 44(3):468-473.
Abstract:
Taking hail disasters in the main tobacco growing areas of Sichuan Province as an example, the important role of the regional natural disaster system theory in combination with the tobacco climatic adaptation characteristics has been studied using the data of hail disaster frequency, DEM (Digital Elevation Model), and ground surface,as well as agricultural socioeconomic data, and the hazard of disastercausing factors, the sensitivity of hazardformation environments, the vulnerability of hazard bearing body, and the capacity of resisting disasters are chosen to construct the meticulous hail disaster risk assessment mathematic model with the help of GIS technology. Based on the tobacco climate adaptability, the hail disaster risk index of the Panxi region is devised. Connected with the practical situation locally, the Panxi region is divided into six parts by using the risk index. The results indicate that the region with high risk is mainly in the source area of the Anning River valley and the Yalong River downstream. Meanwhile, the low mountainous region and hilly areas of the south valley also belong to the highrisk areas. These results provide a scientific basis for hail disaster prevention.
Taking hail disasters in the main tobacco growing areas of Sichuan Province as an example, the important role of the regional natural disaster system theory in combination with the tobacco climatic adaptation characteristics has been studied using the data of hail disaster frequency, DEM (Digital Elevation Model), and ground surface,as well as agricultural socioeconomic data, and the hazard of disastercausing factors, the sensitivity of hazardformation environments, the vulnerability of hazard bearing body, and the capacity of resisting disasters are chosen to construct the meticulous hail disaster risk assessment mathematic model with the help of GIS technology. Based on the tobacco climate adaptability, the hail disaster risk index of the Panxi region is devised. Connected with the practical situation locally, the Panxi region is divided into six parts by using the risk index. The results indicate that the region with high risk is mainly in the source area of the Anning River valley and the Yalong River downstream. Meanwhile, the low mountainous region and hilly areas of the south valley also belong to the highrisk areas. These results provide a scientific basis for hail disaster prevention.
2016, 44(3):474-478.
Abstract:
Using the observation data from partition tests and the monthly mean temperature, monthly mean precipitation, and the number of frostfree days of the three areas from 2004 to 2013, combining with the visiting survey results, the correlation analysis is made between Lingqiu buckwheat ecological distribution and meteorological conditions. Results show that the Beishan area is the main area of Lingqiu County for buckwheat planting. Because of higher elevation, the area has the shorter frostfree period, cooler climate, and larger wind speed, and the microclimate characteristics are in conformity with the bitter buckwheat growth habit. The Nanshan area and the outskirts of Lingqiu are of lower elevation, so they have a longer frostfree period, wetter climate, lower wind speed; along with less per capital arable land, buckwheat planting is given priority to with disaster relief and fallow crop. Buckwheat is a kind of rare crop, with high medicinal value. To study the effect of weather conditions on buckwheat ecological distribution is of great significance for Buckwheat production in Lingqiu.
Using the observation data from partition tests and the monthly mean temperature, monthly mean precipitation, and the number of frostfree days of the three areas from 2004 to 2013, combining with the visiting survey results, the correlation analysis is made between Lingqiu buckwheat ecological distribution and meteorological conditions. Results show that the Beishan area is the main area of Lingqiu County for buckwheat planting. Because of higher elevation, the area has the shorter frostfree period, cooler climate, and larger wind speed, and the microclimate characteristics are in conformity with the bitter buckwheat growth habit. The Nanshan area and the outskirts of Lingqiu are of lower elevation, so they have a longer frostfree period, wetter climate, lower wind speed; along with less per capital arable land, buckwheat planting is given priority to with disaster relief and fallow crop. Buckwheat is a kind of rare crop, with high medicinal value. To study the effect of weather conditions on buckwheat ecological distribution is of great significance for Buckwheat production in Lingqiu.
22 A Case Study of Effectiveness of Artificial Hail SuppressionBased on Dual Polarization Radar Data
2016, 44(3):479-488.
Abstract:
The cloud macrostructure and microphysical characteristics such as particle phase are tracked and analyzed based on the polarization radar data during an artificial hail suppression operation on 11 June 2011. In the analysis, the clouds with the operational conditions similar to those of the seeding area are set as the control area. Both the control area and seeding area are analyzed at different heights before and after seeding based on the echo moving direction and velocity. The results show that the height of the cloud top and strong echo center in the seeding area fell rapidly after the seeding, but the variations in the control area were not obvious. In the seeding area, differential reflectivity〖WTBX〗 Z〖WTBZ〗dr and zero correlation coefficient 〖WTBX〗ρ〖WTBZ〗hv increased with decreasing horizontal reflectivity〖WTBX〗 Z〖WTBZ〗h and differential propagation phase shift 〖WTBX〗K〖WTBZ〗dp fluctuated in small scope. In the control area, 〖WTBX〗ρ〖WTBZ〗hv also increased but the variation of 〖WTBX〗Z〖WTBZ〗h、〖WTBX〗Z〖WTBZ〗dr and〖WTBX〗 K〖WTBZ〗dp were not obvious. In addition, in the seeding area, the convection weakened with obvious falling of large hail particles and big rain drops. In the end, most particles in the clouds were turned to graupel particles. However, in the control area, the convection was still prosperous with the increasing of hail particles. Thus, the characteristics above indicate that the hail suppression work can inhibit the growth from hail embryos into hail effectively, and the effectiveness of the hail suppression work can be better validated through the observing polarized radar parameters.
The cloud macrostructure and microphysical characteristics such as particle phase are tracked and analyzed based on the polarization radar data during an artificial hail suppression operation on 11 June 2011. In the analysis, the clouds with the operational conditions similar to those of the seeding area are set as the control area. Both the control area and seeding area are analyzed at different heights before and after seeding based on the echo moving direction and velocity. The results show that the height of the cloud top and strong echo center in the seeding area fell rapidly after the seeding, but the variations in the control area were not obvious. In the seeding area, differential reflectivity〖WTBX〗 Z〖WTBZ〗dr and zero correlation coefficient 〖WTBX〗ρ〖WTBZ〗hv increased with decreasing horizontal reflectivity〖WTBX〗 Z〖WTBZ〗h and differential propagation phase shift 〖WTBX〗K〖WTBZ〗dp fluctuated in small scope. In the control area, 〖WTBX〗ρ〖WTBZ〗hv also increased but the variation of 〖WTBX〗Z〖WTBZ〗h、〖WTBX〗Z〖WTBZ〗dr and〖WTBX〗 K〖WTBZ〗dp were not obvious. In addition, in the seeding area, the convection weakened with obvious falling of large hail particles and big rain drops. In the end, most particles in the clouds were turned to graupel particles. However, in the control area, the convection was still prosperous with the increasing of hail particles. Thus, the characteristics above indicate that the hail suppression work can inhibit the growth from hail embryos into hail effectively, and the effectiveness of the hail suppression work can be better validated through the observing polarized radar parameters.
2016, 44(3):489-494.
Abstract:
As the grounding of AC and DC equipment and lightning protection equipment, grounding grids play an important role in ensuring the safety of production operation. Measurement results of several plants show that the grounding impedances are all beyond the standard values, and that the inductive component is too big. A comparative analysis between theoretical simulation and measured results of the inductive component of grounding impedance shows that inductive component, which is generally no greater than resistive component, decreases with the increasing distance between current lead and voltage lead, and that excessive inductive component is caused by mutual induction. Based on the above, a method for calculating and eliminating the mutual inductance between the lead wires is brought out, which lays a foundation for reaching the exact grounding impedance.
As the grounding of AC and DC equipment and lightning protection equipment, grounding grids play an important role in ensuring the safety of production operation. Measurement results of several plants show that the grounding impedances are all beyond the standard values, and that the inductive component is too big. A comparative analysis between theoretical simulation and measured results of the inductive component of grounding impedance shows that inductive component, which is generally no greater than resistive component, decreases with the increasing distance between current lead and voltage lead, and that excessive inductive component is caused by mutual induction. Based on the above, a method for calculating and eliminating the mutual inductance between the lead wires is brought out, which lays a foundation for reaching the exact grounding impedance.
2016, 44(3):495-499.
Abstract:
In lightning protection, the lightning protection box is widely used in all kinds of low voltage distribution systems. To investigate the second induction under 8/20 μs impulse current, a great number of experiments based on the Haefely DIAS 733 testing system are carried out. Based on the electromagnetic induction theory, the voltage is calculated and the inductive loop is built in PSPICE. The results indicate: (1) When the design is one port with I/O and parallel wired, the secondinduction voltage amplitude obeys the laws of electromagnetic induction, and can be calculated with higher precision. (2) There are three methods (twintwisted, ground and input line nonparallel, dividual ports of I/O and nonparallel designs) to reduce the electromagnetic induction effectively, and get a lower residual voltage. (3) Experiments show that when the internal wiring scheme adopts the dividual ports of I/O and nonparallel design, the effect is the most obvious. The residual voltage has about 45% reduction at the same sampling points under 60 kA impulse compared with before.
In lightning protection, the lightning protection box is widely used in all kinds of low voltage distribution systems. To investigate the second induction under 8/20 μs impulse current, a great number of experiments based on the Haefely DIAS 733 testing system are carried out. Based on the electromagnetic induction theory, the voltage is calculated and the inductive loop is built in PSPICE. The results indicate: (1) When the design is one port with I/O and parallel wired, the secondinduction voltage amplitude obeys the laws of electromagnetic induction, and can be calculated with higher precision. (2) There are three methods (twintwisted, ground and input line nonparallel, dividual ports of I/O and nonparallel designs) to reduce the electromagnetic induction effectively, and get a lower residual voltage. (3) Experiments show that when the internal wiring scheme adopts the dividual ports of I/O and nonparallel design, the effect is the most obvious. The residual voltage has about 45% reduction at the same sampling points under 60 kA impulse compared with before.
2016, 44(3):500-504.
Abstract:
Lightning electromagnetic pulse is one of main causes of lightning disasters, so the electromagnetic environment assessment is important for protection. Although there is plenty of commercial electromagnetic simulation software on market, most of them have strict system requirements on the computing environment and are timeconsuming for users to build a reasonable model. Traditional commercial software is not suitable for daily lightning protection and evaluation services. For solving this problem， an efficient approach for electromagnetic environment assessment under direct lightning strikes is proposed based on the FiniteDifference TimeDomain (FDTD) method. Simple examples are also provided. It is of great significance to the further research in the field.
Lightning electromagnetic pulse is one of main causes of lightning disasters, so the electromagnetic environment assessment is important for protection. Although there is plenty of commercial electromagnetic simulation software on market, most of them have strict system requirements on the computing environment and are timeconsuming for users to build a reasonable model. Traditional commercial software is not suitable for daily lightning protection and evaluation services. For solving this problem， an efficient approach for electromagnetic environment assessment under direct lightning strikes is proposed based on the FiniteDifference TimeDomain (FDTD) method. Simple examples are also provided. It is of great significance to the further research in the field.
2016, 44(3):505-509.
Abstract:
By means of the lightning tripout data from electricity department and the cloudtoground lightning data obtained by the lightning position network from the Zhejiang Meteorological Service, the spatial and temporal distributions of electric power tripout events from 2007 to 2011 in Zhejiang Province are analyzed. The distances between tripout events and cloudtoground lightning and the relationship between the parameters of cloudtoground lightning data and the voltage classes of lightninginducing tripout events are analyzed. The results show that diurnal and monthly variation of lightning tripout events and cloudtoground lightning exhibit a singlepeak structure, and the correlation coefficients are 0.9905 and 0.9881, respectively. However, their spatial distributions are not significantly correlated. The lightning current intensity inducing tripout events of 110 kV, 220 kV, and 500 kV power lines is below 90 kA in most cases, and the current intensity inducing the tripout of 500 kV line is relatively lower. The distances between cloudtoground lightning and tripout tower are less than 2 km, so are the nearest distances between cloudtoground lightning and transmission lines.
By means of the lightning tripout data from electricity department and the cloudtoground lightning data obtained by the lightning position network from the Zhejiang Meteorological Service, the spatial and temporal distributions of electric power tripout events from 2007 to 2011 in Zhejiang Province are analyzed. The distances between tripout events and cloudtoground lightning and the relationship between the parameters of cloudtoground lightning data and the voltage classes of lightninginducing tripout events are analyzed. The results show that diurnal and monthly variation of lightning tripout events and cloudtoground lightning exhibit a singlepeak structure, and the correlation coefficients are 0.9905 and 0.9881, respectively. However, their spatial distributions are not significantly correlated. The lightning current intensity inducing tripout events of 110 kV, 220 kV, and 500 kV power lines is below 90 kA in most cases, and the current intensity inducing the tripout of 500 kV line is relatively lower. The distances between cloudtoground lightning and tripout tower are less than 2 km, so are the nearest distances between cloudtoground lightning and transmission lines.
2016, 44(3):510-516.
Abstract:
In order to improve the confidence of lightning risk assessment, based on the established risk evaluation index system for lighting disasters in Dalian, the quantification models applied to the evaluation method are explored, and the AHPbased determination method of weights of evaluation indexes are mainly focused. Using AHP to establish judgment matrix of indicators, the most noticeable characteristic of matrix root can be calculated. By means of the normalization and consistency method, the relative weight vector is obtained, and the level of lightning risk is determined. A typical example is used to verify the risk evaluation index system. The result shows that the risk evaluation index system is simple and practical for building lightning risk assessments.
In order to improve the confidence of lightning risk assessment, based on the established risk evaluation index system for lighting disasters in Dalian, the quantification models applied to the evaluation method are explored, and the AHPbased determination method of weights of evaluation indexes are mainly focused. Using AHP to establish judgment matrix of indicators, the most noticeable characteristic of matrix root can be calculated. By means of the normalization and consistency method, the relative weight vector is obtained, and the level of lightning risk is determined. A typical example is used to verify the risk evaluation index system. The result shows that the risk evaluation index system is simple and practical for building lightning risk assessments.
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.