Volume 46,Issue 5,2018 Table of Contents
2018, 46(5):845-854.
Abstract:
Under the background of global warming, the global net radiation monitoring is become more and more important. It has gradually become an important way to study regional synoptic conditions and climate. In order to evaluate the domestic FSJ1 fourcomponent net radiometer, we tested it in Barrow, Alaska (2035°E, 714°N) from 10 to 23 April 2017, compared with the CNR4 fourcomponent net radiometer, which is widely used in the polar regions. The results show that FSJ1 fourcomponent net radiometer performs well in precision and linear correlation under different conditions of clearness and in both daytime and nighttime without icing/riming on surface. The relative error and correlation coefficient of parameters with CNR4 are within 5% and above 09, respectively. However, FSJ1 shows a delay in the response of the radiation change under the influence of polar condition when ice/rime forms on its surface. The relative errors of the pyranometer and pyrgeometer are up to 25% and 7%, respectively. Therefore, it is still a key point to improve the suitable ventilating and heating device for polar radiation stations, and the reasonable filtering method and parameterization scheme are also needed.
Under the background of global warming, the global net radiation monitoring is become more and more important. It has gradually become an important way to study regional synoptic conditions and climate. In order to evaluate the domestic FSJ1 fourcomponent net radiometer, we tested it in Barrow, Alaska (2035°E, 714°N) from 10 to 23 April 2017, compared with the CNR4 fourcomponent net radiometer, which is widely used in the polar regions. The results show that FSJ1 fourcomponent net radiometer performs well in precision and linear correlation under different conditions of clearness and in both daytime and nighttime without icing/riming on surface. The relative error and correlation coefficient of parameters with CNR4 are within 5% and above 09, respectively. However, FSJ1 shows a delay in the response of the radiation change under the influence of polar condition when ice/rime forms on its surface. The relative errors of the pyranometer and pyrgeometer are up to 25% and 7%, respectively. Therefore, it is still a key point to improve the suitable ventilating and heating device for polar radiation stations, and the reasonable filtering method and parameterization scheme are also needed.
2018, 46(5):855-859.
Abstract:
Based on the high verticalresolution position data of Lband and radiosondes, three schemes for calculating secondlevel wind speed are designed by selecting different time windows at different sounding heights. The calculated secondlevel wind speed and ERAInterim reanalysis data are compared on different indexes: the amount of data, the average deviation (Bias), and the root mean square error (RMSE), which indicate the optimal algorithm to calculate the second wind speed. The results show that the appropriate length of time window is necessary to accurately calculate the second wind speed. Given the radar positioning system deviation, the second wind speed error will be larger if the time window is chosen too large or too small. Based on the ERAInterim reanalysis data with good spatial and temporal consistency, this paper presents a new scheme to evaluate the Lband secondlevel wind speed calculation.
Based on the high verticalresolution position data of Lband and radiosondes, three schemes for calculating secondlevel wind speed are designed by selecting different time windows at different sounding heights. The calculated secondlevel wind speed and ERAInterim reanalysis data are compared on different indexes: the amount of data, the average deviation (Bias), and the root mean square error (RMSE), which indicate the optimal algorithm to calculate the second wind speed. The results show that the appropriate length of time window is necessary to accurately calculate the second wind speed. Given the radar positioning system deviation, the second wind speed error will be larger if the time window is chosen too large or too small. Based on the ERAInterim reanalysis data with good spatial and temporal consistency, this paper presents a new scheme to evaluate the Lband secondlevel wind speed calculation.
2018, 46(5):860-867.
Abstract:
The sunlight meter based on the photoelectric principle will be soon popularized and applied in the whole country. The inversion of solar radiation data based on the observation data of light intensity can effectively make up for the insufficient number of solar radiation observation stations. Aiming at the shortcomings of the existing solar radiation estimation methods, a composite model combining with the Principal Component Analysis (PCA), the Mind Evolutionary Algorithm (MEA) and the BP neural network is proposed, using the observation minutes data of solar intensity, solar altitude angle, temperature, and humidity to invert the solar irradiance. Based on the clearness index and the probabilistic neural network (PNN) classification method, the weather types are divided into three categories: sunny, cloudy, and overcast. The classification accuracy is 966948%. Then using the four influencing factors after PCA dimensionality reduction, the solar irradiance is obtained by the BP, GABP and MEABP methods for the three types of weather, and compared with the measured data of the standard radiation meters. The results show that the determination coefficient of the MEABP model is up to 09958 in sunny, cloudy and overcast weather. Compared with the single BP model, RMSE decreases by 49%, 3245% and 1064%, respectively. Compared with the GABP Model error, MAPE decreases by 4254%. The generalization capability of the MEABP composite model proposed in this paper has been effectively improved.
The sunlight meter based on the photoelectric principle will be soon popularized and applied in the whole country. The inversion of solar radiation data based on the observation data of light intensity can effectively make up for the insufficient number of solar radiation observation stations. Aiming at the shortcomings of the existing solar radiation estimation methods, a composite model combining with the Principal Component Analysis (PCA), the Mind Evolutionary Algorithm (MEA) and the BP neural network is proposed, using the observation minutes data of solar intensity, solar altitude angle, temperature, and humidity to invert the solar irradiance. Based on the clearness index and the probabilistic neural network (PNN) classification method, the weather types are divided into three categories: sunny, cloudy, and overcast. The classification accuracy is 966948%. Then using the four influencing factors after PCA dimensionality reduction, the solar irradiance is obtained by the BP, GABP and MEABP methods for the three types of weather, and compared with the measured data of the standard radiation meters. The results show that the determination coefficient of the MEABP model is up to 09958 in sunny, cloudy and overcast weather. Compared with the single BP model, RMSE decreases by 49%, 3245% and 1064%, respectively. Compared with the GABP Model error, MAPE decreases by 4254%. The generalization capability of the MEABP composite model proposed in this paper has been effectively improved.
2018, 46(5):868-874.
Abstract:
A comparative analysis is made of the spatial and temporal distribution characteristics of the cloudtoground (CG) lightning data of Fujian Province in 2015 by means of the threedimensional monitoring and ADTD data for the same period. Using the peak values of lightning current, the detection efficiency and location error check in these two systems are conducted, and at the same time, the cumulative probability distribution of lightning current is analyzed in combination with the probability formula of the IEEE standards and the power industry standards. The results show that the distributions of CG lightning density from two lightning location systems are consistent in Fujian. The distribution of CG lightning density from ADTD is higher than that of the threedimensional system in the southwestern Sanming and some areas of Fuzhou. The monthly and hourly changes of CG lightning frequency are the singlepeak type. The frequency of CG lightning strokes from the threedimensional monitoring system is less than that from ADTD from 09:00 to 12:00 in diurnal variation, and from October to December in annual variation. The detection efficiency of the threedimensional monitoring system is 40%, and the average location error of 275 km is estimated. In the range of 0 to 50 kA, compared with the negative cloudtoground lightning, the current amplitudes of positive cloudtoground lightning from the threedimensional monitoring system are distributed more concentrically, and in the range of 26 to 84 kA, the amplitudes of lightning current are higher than the recommended values of IEEE and the related electricity regulations.
A comparative analysis is made of the spatial and temporal distribution characteristics of the cloudtoground (CG) lightning data of Fujian Province in 2015 by means of the threedimensional monitoring and ADTD data for the same period. Using the peak values of lightning current, the detection efficiency and location error check in these two systems are conducted, and at the same time, the cumulative probability distribution of lightning current is analyzed in combination with the probability formula of the IEEE standards and the power industry standards. The results show that the distributions of CG lightning density from two lightning location systems are consistent in Fujian. The distribution of CG lightning density from ADTD is higher than that of the threedimensional system in the southwestern Sanming and some areas of Fuzhou. The monthly and hourly changes of CG lightning frequency are the singlepeak type. The frequency of CG lightning strokes from the threedimensional monitoring system is less than that from ADTD from 09:00 to 12:00 in diurnal variation, and from October to December in annual variation. The detection efficiency of the threedimensional monitoring system is 40%, and the average location error of 275 km is estimated. In the range of 0 to 50 kA, compared with the negative cloudtoground lightning, the current amplitudes of positive cloudtoground lightning from the threedimensional monitoring system are distributed more concentrically, and in the range of 26 to 84 kA, the amplitudes of lightning current are higher than the recommended values of IEEE and the related electricity regulations.
2018, 46(5):875-879.
Abstract:
The horizontal electric field of lightning is an important parameter for calculating the lightning induced overvoltage on overhead power lines. In order to obtain an accurate value of this parameter, we use the Finite Difference Time Domain (FDTD) method to calculate the lightning electric field under different ground conductivity as well as different distances from the lightning return stroke channel. The results show that in the case of the uniform ground conductivity, the greater of the ground conductivity and the shorter of the distance, the closer the waveform of the horizontal electric field and the input current, because the component of the radiation field in the electric field is relatively small. By increasing the conductivity of the ground or increasing the distance, the calculation results decrease till bipolar characteristic appeared. For the case of the layered ground conductivity, the computed results are influenced more greatly by the upper soil conductivity, but the equivalent resistance is changed by the underlying ground to a certain extent, so that the calculated results are different with the case of uniform ground conductivity.
The horizontal electric field of lightning is an important parameter for calculating the lightning induced overvoltage on overhead power lines. In order to obtain an accurate value of this parameter, we use the Finite Difference Time Domain (FDTD) method to calculate the lightning electric field under different ground conductivity as well as different distances from the lightning return stroke channel. The results show that in the case of the uniform ground conductivity, the greater of the ground conductivity and the shorter of the distance, the closer the waveform of the horizontal electric field and the input current, because the component of the radiation field in the electric field is relatively small. By increasing the conductivity of the ground or increasing the distance, the calculation results decrease till bipolar characteristic appeared. For the case of the layered ground conductivity, the computed results are influenced more greatly by the upper soil conductivity, but the equivalent resistance is changed by the underlying ground to a certain extent, so that the calculated results are different with the case of uniform ground conductivity.
2018, 46(5):880-885.
Abstract:
Vertical detection calibration is an effective way to calibrate the differential reflectivity (〖WTBX〗Z〖WTBZ〗DR) of dualpolarization radar, it can correct measurement errors of 〖WTBX〗Z〖WTBZ〗DR, and improve the quality of the radar data. Based on the simultaneous transmission and reception mode of the Xband dualpolarization radar system, the ZDR product of the Xband dual polarization radar system has a large deviation in some areas, and it can preliminarily concluded that such problem is caused by the azimuth rotary joint by analyzing the radar hardware system and data of the vertical detection calibration. After replacing the damaged with new azimuth rotary joint, this problem can be solved well, which can be verified by the comparing of the data before and after this replacement. Several tests show that the data of vertical detection calibration can correct the ZDR offset effectively when using in the condition of mediumscale stratiform precipitation with the echo intensity between 255 dB and 305 dB.
Vertical detection calibration is an effective way to calibrate the differential reflectivity (〖WTBX〗Z〖WTBZ〗DR) of dualpolarization radar, it can correct measurement errors of 〖WTBX〗Z〖WTBZ〗DR, and improve the quality of the radar data. Based on the simultaneous transmission and reception mode of the Xband dualpolarization radar system, the ZDR product of the Xband dual polarization radar system has a large deviation in some areas, and it can preliminarily concluded that such problem is caused by the azimuth rotary joint by analyzing the radar hardware system and data of the vertical detection calibration. After replacing the damaged with new azimuth rotary joint, this problem can be solved well, which can be verified by the comparing of the data before and after this replacement. Several tests show that the data of vertical detection calibration can correct the ZDR offset effectively when using in the condition of mediumscale stratiform precipitation with the echo intensity between 255 dB and 305 dB.
2018, 46(5):886-891.
Abstract:
Due to the problem that the abnormal telemetry data of meteorological satellites in the threshold rang cannot be detected, this paper proposes the Dynamic Kernel Principal Component Analysis (DKPCA) method to detect the abnormity of satellite telemetry. The telemetry data during the normal operation are collected, and the DKPCA model is established to obtain the control limit of the variable. Then the current telemetry data are detected to determine whether there is a fault. The method solves the problem of sequence correlation between observed data by the dynamic representation of initial data. The introduced DKPCA can transform the nonlinear problem of complex telemetry data into linear problems. The effect is verified by the data of the meteorological satellite FY3C in orbit. The results show that the observed data under normal conditions can be used to detect abnormal satellite telemetry, and the fault omission can be avoided effectively.
Due to the problem that the abnormal telemetry data of meteorological satellites in the threshold rang cannot be detected, this paper proposes the Dynamic Kernel Principal Component Analysis (DKPCA) method to detect the abnormity of satellite telemetry. The telemetry data during the normal operation are collected, and the DKPCA model is established to obtain the control limit of the variable. Then the current telemetry data are detected to determine whether there is a fault. The method solves the problem of sequence correlation between observed data by the dynamic representation of initial data. The introduced DKPCA can transform the nonlinear problem of complex telemetry data into linear problems. The effect is verified by the data of the meteorological satellite FY3C in orbit. The results show that the observed data under normal conditions can be used to detect abnormal satellite telemetry, and the fault omission can be avoided effectively.
2018, 46(5):892-898.
Abstract:
Aiming at the problem of lack of mobile monitoring in numerical weather prediction (NWP) operation systems, the mobile monitoring platform for NWP operation systems is designed and implemented. The platform uses the message middleware technology to obtain the status of the operation systems in real time and uses the pruning algorithm to improve the efficiency of data processing. A mobilefriend data display website is developed to facilitate operation engineers to obtain the status of the operation systems through mobile phones and other mobile devices in real time. By storing the error status, a view of the history abnormal state is provided. Based on the message push interface of the WeChat public platform for the enterprise, the alarm push function is developed, which sends the realtime error messages of the operation systems. The platform is optimized for the mobile internet and mobile devices to speed up platform access. The oneway data flow and the forced use of HTTPS protocol are used to improve the security of the platform. The platform has been applied in operation maintenance service at the Numerical Weather Prediction Center and achieved good results.
Aiming at the problem of lack of mobile monitoring in numerical weather prediction (NWP) operation systems, the mobile monitoring platform for NWP operation systems is designed and implemented. The platform uses the message middleware technology to obtain the status of the operation systems in real time and uses the pruning algorithm to improve the efficiency of data processing. A mobilefriend data display website is developed to facilitate operation engineers to obtain the status of the operation systems through mobile phones and other mobile devices in real time. By storing the error status, a view of the history abnormal state is provided. Based on the message push interface of the WeChat public platform for the enterprise, the alarm push function is developed, which sends the realtime error messages of the operation systems. The platform is optimized for the mobile internet and mobile devices to speed up platform access. The oneway data flow and the forced use of HTTPS protocol are used to improve the security of the platform. The platform has been applied in operation maintenance service at the Numerical Weather Prediction Center and achieved good results.
2018, 46(5):899-909.
Abstract:
Nowadays，main nowcasting techniques comprise three aspects： extrapolation forecast， numerical model forecast，and knowledgebased forecast technique. The mainstream nowcasting technique is still extrapolation forecast，which is mainly based on radar data， and use the radar echo cell tracking algorithm or radar echo area tracking algorithm to obtain the extrapolation nowcasting of precipitation echoes and rainfall. In this paper, the advances in researches and the basic principles on the three radar echo area tracking algorithms (Tracking Radar Echoes by Correlation， Optical Flow, and Variational Echo Tracker) are introduced. Based on scientific researches and operational practices，the radar echo area tracking algorithm, which is a key part of nowcasting expert system，preferably has predictability in convective weather nowcasting， and the extrapolation prediction is more closer to observation than numerical model prediction. With the continuous improvement of the algorithms， the predictability in convective weather nowcasting for all nowcasting expert systems increased. With the development of weather radar technique on both hardware and software， the quality of radar data is gradually improved. In convective weather nowcasting， the nowcasting techniques based on radar echo area tracking algorithm will highlight their obvious advantages.
Nowadays，main nowcasting techniques comprise three aspects： extrapolation forecast， numerical model forecast，and knowledgebased forecast technique. The mainstream nowcasting technique is still extrapolation forecast，which is mainly based on radar data， and use the radar echo cell tracking algorithm or radar echo area tracking algorithm to obtain the extrapolation nowcasting of precipitation echoes and rainfall. In this paper, the advances in researches and the basic principles on the three radar echo area tracking algorithms (Tracking Radar Echoes by Correlation， Optical Flow, and Variational Echo Tracker) are introduced. Based on scientific researches and operational practices，the radar echo area tracking algorithm, which is a key part of nowcasting expert system，preferably has predictability in convective weather nowcasting， and the extrapolation prediction is more closer to observation than numerical model prediction. With the continuous improvement of the algorithms， the predictability in convective weather nowcasting for all nowcasting expert systems increased. With the development of weather radar technique on both hardware and software， the quality of radar data is gradually improved. In convective weather nowcasting， the nowcasting techniques based on radar echo area tracking algorithm will highlight their obvious advantages.
2018, 46(5):910-918.
Abstract:
Fine grid forecast is the main service of the China Meteorological Administration, and also the future development direction of weather forecast. This system improves the spatial resolution (0025°×0025°), and at the same time, meteorological elements such as precipitation and temperature forecast quality. This article described the technical methods in the data products of this system, from four aspects: (1) established the technical framework for grid forecast, using the Dynamic Cross Optimal Elements Forecast (DCOEF) method to establish the background field of grid forecast, which means comparing different model’s element forecast results and selecting that with higher forecast quality in past 15 days as the base field for forecasters; (2) proposed the method of “stationrevised value transmitting to the grid field” for consecutive elements correction. The cross test shows that the accurate rate of 24hour minimum and maximum temperature (<2 ℃) are improved by 34% and 23%, respectively, by this method compared to the model downscaling data, and also, the method has better application value in the combination of the background field collaborative and subjective station forecast and objective grid element forecasts; (3) based on the Bias Correction method to correct grid precipitation; the results show that through calculating forecast bias to decrease light rain frequency and increase rainstrom frequency, the 24hour TS (Threat Score) improved by 25% and 482%, respectively, compared to the original model. (4) proposed the reverse deviation data normalization algorithm to deal the inconsistent problem of the objective or subjective correction data in the time series, which does not change the elements forecast trends of original models, and at the same time, the elements are coordinated in time, so to solve the problem of time coordination of grid elements.
Fine grid forecast is the main service of the China Meteorological Administration, and also the future development direction of weather forecast. This system improves the spatial resolution (0025°×0025°), and at the same time, meteorological elements such as precipitation and temperature forecast quality. This article described the technical methods in the data products of this system, from four aspects: (1) established the technical framework for grid forecast, using the Dynamic Cross Optimal Elements Forecast (DCOEF) method to establish the background field of grid forecast, which means comparing different model’s element forecast results and selecting that with higher forecast quality in past 15 days as the base field for forecasters; (2) proposed the method of “stationrevised value transmitting to the grid field” for consecutive elements correction. The cross test shows that the accurate rate of 24hour minimum and maximum temperature (<2 ℃) are improved by 34% and 23%, respectively, by this method compared to the model downscaling data, and also, the method has better application value in the combination of the background field collaborative and subjective station forecast and objective grid element forecasts; (3) based on the Bias Correction method to correct grid precipitation; the results show that through calculating forecast bias to decrease light rain frequency and increase rainstrom frequency, the 24hour TS (Threat Score) improved by 25% and 482%, respectively, compared to the original model. (4) proposed the reverse deviation data normalization algorithm to deal the inconsistent problem of the objective or subjective correction data in the time series, which does not change the elements forecast trends of original models, and at the same time, the elements are coordinated in time, so to solve the problem of time coordination of grid elements.
2018, 46(5):919-931.
Abstract:
Using the surface observation, MICAPS and NCEP data from 1951 to 2013, the 700 hPa influence systems of 150 heavy snowstorms occurred in the southeastern Inner Mongolia are divided into seven types, and for the 26 heavy snowstorms from 2007 to 2013, the physical quantity fields are classified and analyzed for 25 stations. The results show: Overall, the divergence field had the characteristics of the lowlevel convergence and highlevel divergence, which corresponded to the coupling effect of high and low jet streams. The vertical velocity field and a long time strong updraft in the whole layer maintained. Depending on the height of the weather patterns, the maximum relative humidity was between 925 and 500 hPa, and the water vapor flux divergence/convergence was mainly between 925 and 700 hPa. With high elevation, the specific humidity rapidly decreased. The minimum humidity for various weather patterns at 925 hPa was 2 to 29 g〖DK〗·kg-1, and that at 850 hPa was 17 to 32 g〖DK〗·kg-1, reflecting the effect of the lowlevel southwest warm water jet, especially the contribution of the 925 hPa superlow jet stream. At the 1000 hPa (the 75th percentile) near the ground layer there was basically cold advection. Above 925 hPa there was all warm advection, which had obvious “cold cushion” effect and provided the trigger conditions for the heavy snowstorm.
Using the surface observation, MICAPS and NCEP data from 1951 to 2013, the 700 hPa influence systems of 150 heavy snowstorms occurred in the southeastern Inner Mongolia are divided into seven types, and for the 26 heavy snowstorms from 2007 to 2013, the physical quantity fields are classified and analyzed for 25 stations. The results show: Overall, the divergence field had the characteristics of the lowlevel convergence and highlevel divergence, which corresponded to the coupling effect of high and low jet streams. The vertical velocity field and a long time strong updraft in the whole layer maintained. Depending on the height of the weather patterns, the maximum relative humidity was between 925 and 500 hPa, and the water vapor flux divergence/convergence was mainly between 925 and 700 hPa. With high elevation, the specific humidity rapidly decreased. The minimum humidity for various weather patterns at 925 hPa was 2 to 29 g〖DK〗·kg-1, and that at 850 hPa was 17 to 32 g〖DK〗·kg-1, reflecting the effect of the lowlevel southwest warm water jet, especially the contribution of the 925 hPa superlow jet stream. At the 1000 hPa (the 75th percentile) near the ground layer there was basically cold advection. Above 925 hPa there was all warm advection, which had obvious “cold cushion” effect and provided the trigger conditions for the heavy snowstorm.
2018, 46(5):932-942.
Abstract:
In order to compare the effects of different longwave radiation and shortwave radiation parameterization schemes on the numerical simulations of radiation fog processes, in this paper, the two typical heavy radiation fog events occurred in Jiangsu Province in spring and autumn 2015 are screened respectively and the Weather Research and Forecast Model (WRF) is used in the numerical simulations of these two radiation fog processes through the design of different longwave and shortwave radiation parameterization schemes. The influences of these longwave and shortwave radiation parameterization schemes on the numerical simulation of the fog processes are discussed. The mean absolute error (MAR), the root mean square error (RMSE), the Pearson correlation coefficient and Fog Grade and the Fog Area Forecast Regulations promulgated by the China Meteorological Administration are used to evaluate these simulation schemes, and the optimal simulation schemes under the different conditions are obtained. The results show: (1) In the simulations of the relative humidity and the dew point temperature as the vapor conditions of fog occurrence or in the simulations of the air temperature and surface temperature as the thermodynamic conditions, the optimal scheme is the combination of GFDL scheme in the long wave radiation with the RRTMG scheme in the short wave radiation. (2) In the simulations of the wind speed at the 10 m level, for the dynamic condition of fog engendering, the optimal scheme is the combination of CAM scheme in the long wave radiation with the FLG scheme in short wave radiation. (3) For the simulation of the fog area, the scheme combined with the best simulation effectiveness is the combination of the GFDL scheme in the long wave radiation with the RRTMG scheme in short wave radiation.
In order to compare the effects of different longwave radiation and shortwave radiation parameterization schemes on the numerical simulations of radiation fog processes, in this paper, the two typical heavy radiation fog events occurred in Jiangsu Province in spring and autumn 2015 are screened respectively and the Weather Research and Forecast Model (WRF) is used in the numerical simulations of these two radiation fog processes through the design of different longwave and shortwave radiation parameterization schemes. The influences of these longwave and shortwave radiation parameterization schemes on the numerical simulation of the fog processes are discussed. The mean absolute error (MAR), the root mean square error (RMSE), the Pearson correlation coefficient and Fog Grade and the Fog Area Forecast Regulations promulgated by the China Meteorological Administration are used to evaluate these simulation schemes, and the optimal simulation schemes under the different conditions are obtained. The results show: (1) In the simulations of the relative humidity and the dew point temperature as the vapor conditions of fog occurrence or in the simulations of the air temperature and surface temperature as the thermodynamic conditions, the optimal scheme is the combination of GFDL scheme in the long wave radiation with the RRTMG scheme in the short wave radiation. (2) In the simulations of the wind speed at the 10 m level, for the dynamic condition of fog engendering, the optimal scheme is the combination of CAM scheme in the long wave radiation with the FLG scheme in short wave radiation. (3) For the simulation of the fog area, the scheme combined with the best simulation effectiveness is the combination of the GFDL scheme in the long wave radiation with the RRTMG scheme in short wave radiation.
2018, 46(5):943-950.
Abstract:
Based on the FY2D/E satellite and thunderstorm data in summer from 2010 to 2014, the satellite image characteristics of newborn thunderstorms and their formation mechanisms in the Eastern QinghaiXizang Plateau are analyzed. The results show that the satellite image characteristics of thunderstorms have obvious features, and the cloud top, which has a high correlation with altitude, is below the tropopause. In general, the TBB of the IR channel (IR1) often ranges from -55 ℃ to -10 ℃, and the TBB of the vapor channel (IR3) has a high frequency from -50 ℃ to -30 ℃. The TBB difference between IR2 (TBB of the splitwindow channel) and IR1 has a high frequency around -33 ℃, and the TBB difference between IR3 and IR1, which is greater than 0 ℃, reaches 83%. In addition, the differences between the surface and air temperature often appear from 5 ℃ to 15 ℃, while the surface temperature is basically from 25 ℃ to 30 ℃ and the relative humidity between 40% to 55% and 30% to 50% in regions Ⅰand Ⅱ. But the differences between the surface and air temperature often range from 5 ℃ to 10 ℃, and the surface temperature is concentrated mainly from 30 ℃ to 35 ℃ in the Ⅲ region. The differences between the surface and air temperature, surface temperature, and relative humidity conditions are reasonable and can be good indicators of newborn thunderstorms in the eastern QinghaiXizang Plateau.
Based on the FY2D/E satellite and thunderstorm data in summer from 2010 to 2014, the satellite image characteristics of newborn thunderstorms and their formation mechanisms in the Eastern QinghaiXizang Plateau are analyzed. The results show that the satellite image characteristics of thunderstorms have obvious features, and the cloud top, which has a high correlation with altitude, is below the tropopause. In general, the TBB of the IR channel (IR1) often ranges from -55 ℃ to -10 ℃, and the TBB of the vapor channel (IR3) has a high frequency from -50 ℃ to -30 ℃. The TBB difference between IR2 (TBB of the splitwindow channel) and IR1 has a high frequency around -33 ℃, and the TBB difference between IR3 and IR1, which is greater than 0 ℃, reaches 83%. In addition, the differences between the surface and air temperature often appear from 5 ℃ to 15 ℃, while the surface temperature is basically from 25 ℃ to 30 ℃ and the relative humidity between 40% to 55% and 30% to 50% in regions Ⅰand Ⅱ. But the differences between the surface and air temperature often range from 5 ℃ to 10 ℃, and the surface temperature is concentrated mainly from 30 ℃ to 35 ℃ in the Ⅲ region. The differences between the surface and air temperature, surface temperature, and relative humidity conditions are reasonable and can be good indicators of newborn thunderstorms in the eastern QinghaiXizang Plateau.
2018, 46(5):951-957.
Abstract:
An analysis is made of the water vapor transport characteristics of a sudden heavy rainstorm occurred in Huaping, the northwestern Yunnan Plateau, using the conventional calculation and numerical simulation method. The results show: The stable maintenance of the tropical depression in the IndoChina Peninsula and the depression in the Bay of Bengal provided a largescale environmental field for the establishment of the water vapor transport channel in the rainstorm area. There were two water vapor transport channels in the rainstorm area: the water vapor transport on the east side of the depression in the Bay of Bengal and that on the south side of subtropical high, of which the source area can be traced back to the South China Sea, the Western Pacific, the Bay of Bengal, the Arabian Sea, etc. The water vapor transport and water vapor convergence mainly came from the lower levels below 700 hPa, and the water vapor transport characteristics of 700 hPa and 850 hPa were consistent with that of the whole layer. The numerical simulation results can better reproduce the characteristics of water vapor transport in the rainstorm area, and at the same time, during the back tracking period, the middle and low water vapor transport in the storm area started above this height, and along with the occurrence of heavy rain, the water vapor transport height gradually reduced.
An analysis is made of the water vapor transport characteristics of a sudden heavy rainstorm occurred in Huaping, the northwestern Yunnan Plateau, using the conventional calculation and numerical simulation method. The results show: The stable maintenance of the tropical depression in the IndoChina Peninsula and the depression in the Bay of Bengal provided a largescale environmental field for the establishment of the water vapor transport channel in the rainstorm area. There were two water vapor transport channels in the rainstorm area: the water vapor transport on the east side of the depression in the Bay of Bengal and that on the south side of subtropical high, of which the source area can be traced back to the South China Sea, the Western Pacific, the Bay of Bengal, the Arabian Sea, etc. The water vapor transport and water vapor convergence mainly came from the lower levels below 700 hPa, and the water vapor transport characteristics of 700 hPa and 850 hPa were consistent with that of the whole layer. The numerical simulation results can better reproduce the characteristics of water vapor transport in the rainstorm area, and at the same time, during the back tracking period, the middle and low water vapor transport in the storm area started above this height, and along with the occurrence of heavy rain, the water vapor transport height gradually reduced.
2018, 46(5):958-964.
Abstract:
Based on the observation data of nine kinds of lowvisibility phenomena (mist, fog, snowstorm, blowing snow, smoke, haze, sand storm, blowing sand, and dust) in Sichuan Province from 1981 to 2013, we discuss the number of occurrence days, occurrence probability, and space distribution characteristics. The results show that the number of occurrence days of lowvisibility phenomena in Sichuan Province was: mist > fog > haze > dust > smoke > blowing sand > sandstorm > blowing snow > snowstorm. The numbers of mist and fog days were 176 days and 29 days, and the probability of daily occurrence was 48% and 8%, far higher than other weather phenomena. As for seasonal variation, fog and haze mainly occurred in autumn and winter, and haze, blowing snow, and snowstorm in winter, sand dust in spring, dust storms mainly in winter and spring, and smoke mainly in spring and autumn. The trend of mist in Sichuan remained stable; the smoke was increasing; and the fog, haze, sandstorm, blowing sand and dust were descending. The stable atmosphere, sufficient water vapor, week wind, concentrated population and large emissions were favorable to the formation of fog, mist, basin haze and smoke. Unreasonable use of water and land resources and dust weather in North China along with the southward movement of cold air are the important causes of sand dust weather. Blowing snow and snowstorm occurred in the western Sichuan plateau with larger winter snowfall and higher wind speed.
Based on the observation data of nine kinds of lowvisibility phenomena (mist, fog, snowstorm, blowing snow, smoke, haze, sand storm, blowing sand, and dust) in Sichuan Province from 1981 to 2013, we discuss the number of occurrence days, occurrence probability, and space distribution characteristics. The results show that the number of occurrence days of lowvisibility phenomena in Sichuan Province was: mist > fog > haze > dust > smoke > blowing sand > sandstorm > blowing snow > snowstorm. The numbers of mist and fog days were 176 days and 29 days, and the probability of daily occurrence was 48% and 8%, far higher than other weather phenomena. As for seasonal variation, fog and haze mainly occurred in autumn and winter, and haze, blowing snow, and snowstorm in winter, sand dust in spring, dust storms mainly in winter and spring, and smoke mainly in spring and autumn. The trend of mist in Sichuan remained stable; the smoke was increasing; and the fog, haze, sandstorm, blowing sand and dust were descending. The stable atmosphere, sufficient water vapor, week wind, concentrated population and large emissions were favorable to the formation of fog, mist, basin haze and smoke. Unreasonable use of water and land resources and dust weather in North China along with the southward movement of cold air are the important causes of sand dust weather. Blowing snow and snowstorm occurred in the western Sichuan plateau with larger winter snowfall and higher wind speed.
2018, 46(5):965-970.
Abstract:
Based on the unconventional observation data, such as wind profile data, microwave radiometer data, and VDRAS 5km resolution data, a comparison analysis is conducted on the application of multisource observation data in forecasting of a heavy rainstorm in July 2016 The results indicate that the wind profiles provided highly similar data with the VDRAS vertical wind field in the upperlevel trough and surface cyclone precipitation periods of the weather process. Measurements from the microradiometer highly fitted those from the VDRAS observations, indicating the observational data from both instruments are credible. The fluctuation of the wind field at the edge of the wind profile layer was a good indicator for the timing prediction of highintensity rainfall during the warm area before the front and upperlevel trough precipitation processes. The lowlevel jet was directly related with the time period of surface cyclone precipitation. The rapid increase of the specific humidity was a good indication for correcting the shortduration and nowcasting precipitation.
Based on the unconventional observation data, such as wind profile data, microwave radiometer data, and VDRAS 5km resolution data, a comparison analysis is conducted on the application of multisource observation data in forecasting of a heavy rainstorm in July 2016 The results indicate that the wind profiles provided highly similar data with the VDRAS vertical wind field in the upperlevel trough and surface cyclone precipitation periods of the weather process. Measurements from the microradiometer highly fitted those from the VDRAS observations, indicating the observational data from both instruments are credible. The fluctuation of the wind field at the edge of the wind profile layer was a good indicator for the timing prediction of highintensity rainfall during the warm area before the front and upperlevel trough precipitation processes. The lowlevel jet was directly related with the time period of surface cyclone precipitation. The rapid increase of the specific humidity was a good indication for correcting the shortduration and nowcasting precipitation.
2018, 46(5):971-978.
Abstract:
The snowstorm process against the background of northeast cold vortex in the Daxinganling region on 13 and 14 November 2016 is analyzed using the routine observational data, FY2 satellite water vapor images, Doppler radar data and NCEP (1°×1°) reanalysis data with the resolution of 6 hours. The results indicate that the transversal trough from the rear of the upper cold vortex southward caused the drycold air southward and the lowlevel southwest jet in front of the cold vortex northwardjumping; moreover, the convergence which strengthened sharply provided the favorable circulation conditions for the snowstorm. The lowlevel southwest jet (≥20 m〖DK〗·s-1) as the moisture transport belt provided adequate water vapor for the snowstorm. The center of the vertical ascending motion was corresponding to the location of the center of the convergence and strengthened gradually, which offered the dynamic conditions for the snowstorm and promoted the development of ascending motion. The snowstorm process occurred against the background of the conditional symmetric instability where the moist potential vorticity MPV2<0 occurred, and the center of snowstorm was located in the intensive belt of MPV2 isolines and the area where MPV2 absolute value increased greatly. The water vapor image shows the dry seam and hatchet dark areas which is the characteristics of the dry intrusion. The radar echo shows that the lowlevel southeast jet was very significant. When the ultrastrong lower level southeast warm and moist air was vertical to the Daxinganling Mountains from the northeast to southwest, due to the topography effect, the ascending motion on the windward slope strengthened rapidly and the moisture convergence in lower layers strengthened and maintained, which offered the abundant moistures for the snowstorm, which was a major reason why the snowstorm was mainly distributed in the eastern foot of Daxinganling Mountains.
The snowstorm process against the background of northeast cold vortex in the Daxinganling region on 13 and 14 November 2016 is analyzed using the routine observational data, FY2 satellite water vapor images, Doppler radar data and NCEP (1°×1°) reanalysis data with the resolution of 6 hours. The results indicate that the transversal trough from the rear of the upper cold vortex southward caused the drycold air southward and the lowlevel southwest jet in front of the cold vortex northwardjumping; moreover, the convergence which strengthened sharply provided the favorable circulation conditions for the snowstorm. The lowlevel southwest jet (≥20 m〖DK〗·s-1) as the moisture transport belt provided adequate water vapor for the snowstorm. The center of the vertical ascending motion was corresponding to the location of the center of the convergence and strengthened gradually, which offered the dynamic conditions for the snowstorm and promoted the development of ascending motion. The snowstorm process occurred against the background of the conditional symmetric instability where the moist potential vorticity MPV2<0 occurred, and the center of snowstorm was located in the intensive belt of MPV2 isolines and the area where MPV2 absolute value increased greatly. The water vapor image shows the dry seam and hatchet dark areas which is the characteristics of the dry intrusion. The radar echo shows that the lowlevel southeast jet was very significant. When the ultrastrong lower level southeast warm and moist air was vertical to the Daxinganling Mountains from the northeast to southwest, due to the topography effect, the ascending motion on the windward slope strengthened rapidly and the moisture convergence in lower layers strengthened and maintained, which offered the abundant moistures for the snowstorm, which was a major reason why the snowstorm was mainly distributed in the eastern foot of Daxinganling Mountains.
2018, 46(5):979-987.
Abstract:
The new generation Doppler radar observation data from Xi'an Radar Station, NCEP reanalysis data, and automatic station data are used to study the gust front around Xianyang Airport on 4 June 2016 This weather process was caused by the convection triggered by the southerly cold air behind the Mongolian low vortex and produced 22 mm precipitation and 197 m〖DK〗·s-1 gust over Xianyang Airport, which influenced several flights. From the radar echoes, it is found that the life cycle of the gust front was about 2 hours; the echo intensity was about 5 to 25 dBz; the length was about 70 km; and the average speed was 497 km〖DK〗·h-1, with obvious narrowband and convergence line existing. After the quality control of radar data, the automatic identification software is designed; the bidirectional gradient algorithm is used in the intensity field; and the Shear parameter algorithm is used in the velocity field. According to the spatial consistency of narrowband and the convergence line, the location and intensity of the gust front are recognized. Finally, the critical success index is used to evaluate the software. The recognition rate of this gust front reaches 8333%, which shows that the software can identify gust front and can be used in service.
The new generation Doppler radar observation data from Xi'an Radar Station, NCEP reanalysis data, and automatic station data are used to study the gust front around Xianyang Airport on 4 June 2016 This weather process was caused by the convection triggered by the southerly cold air behind the Mongolian low vortex and produced 22 mm precipitation and 197 m〖DK〗·s-1 gust over Xianyang Airport, which influenced several flights. From the radar echoes, it is found that the life cycle of the gust front was about 2 hours; the echo intensity was about 5 to 25 dBz; the length was about 70 km; and the average speed was 497 km〖DK〗·h-1, with obvious narrowband and convergence line existing. After the quality control of radar data, the automatic identification software is designed; the bidirectional gradient algorithm is used in the intensity field; and the Shear parameter algorithm is used in the velocity field. According to the spatial consistency of narrowband and the convergence line, the location and intensity of the gust front are recognized. Finally, the critical success index is used to evaluate the software. The recognition rate of this gust front reaches 8333%, which shows that the software can identify gust front and can be used in service.
2018, 46(5):988-998.
Abstract:
Based on the daily precipitation, temperature, and soil relative humidity data of 77 stations in Anhui Province from 1981 to 2016, the Gomprehensive Meteorological Drought Index (MCI_anhui) for dry season (October to March) and flood season (April to September) is constructed by using the correlation and principal component analysis methods. In respects of the frequency distribution, evolution of drought days, illogical jumping times and typical drought processes for representative stations, the applicability of four meteorological drought indices in Anhui is analyzed through contrasts. The results show that the MCI_anhui is superior to others in reflecting the meteorological drought with heavier grades, which can well diagnose typical drought years in the history of Anhui. The number of drought days calculated from this index shows that droughts in the areas along and north of the Huaihe River occurred mostly in summer and late spring, while in the areas between Huaihe and Yangtze River, droughts mainly occurred in late spring and early summer, and in the areas along and south of the Yangtze River, droughts mainly occurred in autumn. The illogical jumping times of all drought processes in 36 years were less than 10 In terms of its sensitivity to precipitation during typical drought processes, it is represented that the MCI_anhui with less illogical jumping times is not only superior to others in reflecting slowly progressive characteristics of drought, but also less excessively sensitive during the later period of drought. In general, the MCI_anhui has a better ability to identify and diagnose drought processes and favorable applicability in Anhui Province.
Based on the daily precipitation, temperature, and soil relative humidity data of 77 stations in Anhui Province from 1981 to 2016, the Gomprehensive Meteorological Drought Index (MCI_anhui) for dry season (October to March) and flood season (April to September) is constructed by using the correlation and principal component analysis methods. In respects of the frequency distribution, evolution of drought days, illogical jumping times and typical drought processes for representative stations, the applicability of four meteorological drought indices in Anhui is analyzed through contrasts. The results show that the MCI_anhui is superior to others in reflecting the meteorological drought with heavier grades, which can well diagnose typical drought years in the history of Anhui. The number of drought days calculated from this index shows that droughts in the areas along and north of the Huaihe River occurred mostly in summer and late spring, while in the areas between Huaihe and Yangtze River, droughts mainly occurred in late spring and early summer, and in the areas along and south of the Yangtze River, droughts mainly occurred in autumn. The illogical jumping times of all drought processes in 36 years were less than 10 In terms of its sensitivity to precipitation during typical drought processes, it is represented that the MCI_anhui with less illogical jumping times is not only superior to others in reflecting slowly progressive characteristics of drought, but also less excessively sensitive during the later period of drought. In general, the MCI_anhui has a better ability to identify and diagnose drought processes and favorable applicability in Anhui Province.
2018, 46(5):999-1003.
Abstract:
Applying the lowfrequency synoptic map, the statistical prediction model of heavy rainfall in Guizhou Province is established based on the EOF analysis and statistical analysis of 500 hPa low frequency flow field corresponding to 59 regional precipitation processes from 2011 to 2015 The local applicability of the method is assessed by means of the accuracy rate of the 2016 forecast results applying extrapolation. The results indicate that the six key regions of the low frequency systems for Guizhou heavy rainfall are: west of Lake Baikal (Region 1, 40° to 70°N, 80° to 110°E), east of Lake Baikal (Region 2, 40° to 70°N, 110° to 150°E), east of Southwest China to central China (Region 3, 25° to 40°N, 100° to 120°E), western Pacific (Region 4, 10° to 40°N, 120° to 140°E), Bay of Bengal (Region 5, 0° to 25°N, 70° to 100°E), southern of China (Region 6,0° to 25°N, 100° to 120°E). The prediction model of the heavy rainfall in Guizhou is: the low frequency anticyclone appeared in the Region 1 and the low frequency cyclone in Regions 3 and 5 and the low frequency system activity in Regions 2 and 6 According to the cycle of the low frequency system in each key area, the forecasting experiment was carried out in 2016 flood season. The prediction accuracy was 392%, which indicates that the application of low frequency map method is well in predicting the heavy rainfall process in Guizhou.
Applying the lowfrequency synoptic map, the statistical prediction model of heavy rainfall in Guizhou Province is established based on the EOF analysis and statistical analysis of 500 hPa low frequency flow field corresponding to 59 regional precipitation processes from 2011 to 2015 The local applicability of the method is assessed by means of the accuracy rate of the 2016 forecast results applying extrapolation. The results indicate that the six key regions of the low frequency systems for Guizhou heavy rainfall are: west of Lake Baikal (Region 1, 40° to 70°N, 80° to 110°E), east of Lake Baikal (Region 2, 40° to 70°N, 110° to 150°E), east of Southwest China to central China (Region 3, 25° to 40°N, 100° to 120°E), western Pacific (Region 4, 10° to 40°N, 120° to 140°E), Bay of Bengal (Region 5, 0° to 25°N, 70° to 100°E), southern of China (Region 6,0° to 25°N, 100° to 120°E). The prediction model of the heavy rainfall in Guizhou is: the low frequency anticyclone appeared in the Region 1 and the low frequency cyclone in Regions 3 and 5 and the low frequency system activity in Regions 2 and 6 According to the cycle of the low frequency system in each key area, the forecasting experiment was carried out in 2016 flood season. The prediction accuracy was 392%, which indicates that the application of low frequency map method is well in predicting the heavy rainfall process in Guizhou.
2018, 46(5):1004-1011.
Abstract:
In the context of climate change, extreme precipitation is increasing gradually with the increase of urban rain island effect. In this paper, the Shanghai Urban flooding assessment Model (SUM) is used to analyze the urban flooding vulnerability characteristics in different drainage blocks. On the basis of the future rainfall intensity simulation, urban flooding scenarios in the downtown are established to analyze the influence of climate change on urban drainage. This paper also makes an assessment of urban flooding adaptability in Shanghai in the context of climate change of RCP45 and RCP85 The results indicate that the urban flooding vulnerability in the districts of Jing’an, Huangpu, Hongkou, and Changning is relatively higher than that in other areas. Under climate change, the urban flooding will be strengthened gradually. Taking the precipitation recurrence period of once every three years as an example, the increase of flooded area in the central area is about 374 km2/10a. Under the current drainage capacity, the average growth of 1486% per decade of the pervious area for various drainage blocks can offset the strength of urban flooding caused by climate change, and the expected increase of the pervious area in Pudong will be lower than that in Puxi.
In the context of climate change, extreme precipitation is increasing gradually with the increase of urban rain island effect. In this paper, the Shanghai Urban flooding assessment Model (SUM) is used to analyze the urban flooding vulnerability characteristics in different drainage blocks. On the basis of the future rainfall intensity simulation, urban flooding scenarios in the downtown are established to analyze the influence of climate change on urban drainage. This paper also makes an assessment of urban flooding adaptability in Shanghai in the context of climate change of RCP45 and RCP85 The results indicate that the urban flooding vulnerability in the districts of Jing’an, Huangpu, Hongkou, and Changning is relatively higher than that in other areas. Under climate change, the urban flooding will be strengthened gradually. Taking the precipitation recurrence period of once every three years as an example, the increase of flooded area in the central area is about 374 km2/10a. Under the current drainage capacity, the average growth of 1486% per decade of the pervious area for various drainage blocks can offset the strength of urban flooding caused by climate change, and the expected increase of the pervious area in Pudong will be lower than that in Puxi.
22 Characteristics of AQI and Relationship with Meteorological Factors in Three Terrains over Hubei
2018, 46(5):1012-1019.
Abstract:
Based on the data of environmental monitoring and meteorological elements in Hubei Province in 2015 and 2016, this paper analyzes the characteristics of air quality and its relationship with meteorological factors in three kinds of terrains. The results show that the temporal and spatial distribution of air quality in Hubei Province was low in mountain and high in plain areas, and the high value of AQI in winter and low value of that in summer. It is shown that the daily maximum AQI of Xiangyang appeared at noon, and the highest value of Wuhan and Yichang appeared from 23:00 to 24:00 Meteorological factors that have obvious relationship with air quality include relative humidity, variable temperature and pressure, wind, precipitation, of which precipitation effect on pollutant sedimentation is related to the air quality grade. The heavier the pollution, the greater the amount of rain needed to clean the air. For mild and above pollution, moderate and above precipitation will be effective for clean air. When precipitation is in trace level (below 1 mm), there will be a growing trend in AQI. Under different terrain influences, there blew mainly north winds in Xiangyang, northwest winds in Wuhan and the weak easterly wind disturbance in Yichang in case of heavy pollution. The occurence frequency of large wind speed in Xiangyang was obviously higher than the others, and Yichang was dominated by breeze.
Based on the data of environmental monitoring and meteorological elements in Hubei Province in 2015 and 2016, this paper analyzes the characteristics of air quality and its relationship with meteorological factors in three kinds of terrains. The results show that the temporal and spatial distribution of air quality in Hubei Province was low in mountain and high in plain areas, and the high value of AQI in winter and low value of that in summer. It is shown that the daily maximum AQI of Xiangyang appeared at noon, and the highest value of Wuhan and Yichang appeared from 23:00 to 24:00 Meteorological factors that have obvious relationship with air quality include relative humidity, variable temperature and pressure, wind, precipitation, of which precipitation effect on pollutant sedimentation is related to the air quality grade. The heavier the pollution, the greater the amount of rain needed to clean the air. For mild and above pollution, moderate and above precipitation will be effective for clean air. When precipitation is in trace level (below 1 mm), there will be a growing trend in AQI. Under different terrain influences, there blew mainly north winds in Xiangyang, northwest winds in Wuhan and the weak easterly wind disturbance in Yichang in case of heavy pollution. The occurence frequency of large wind speed in Xiangyang was obviously higher than the others, and Yichang was dominated by breeze.
2018, 46(5):1020-1025.
Abstract:
An analysis is made of the correlation between atmospheric instability parameters and lightning activities in the low latitude plateau region in this paper using the lightning information and radiosonde data in Yunnan Province from 2014 to 2017 Five parameters selected from 9 are strongly correlated. The threshold of lightning occurrence for each parameter is determined by means of the mathematical method. The complex correlation coefficient method is used to calculate the weight of each parameter and set up the prediction equation for lightning potential. Finally, the equation is verified by means of forecasting and case analysis. The results show that the atmospheric instability parameters over the low latitude plateau are sensitive to lightning activities. The response threshold is generally lower than that of the plain area. The prediction effectiveness of the prediction equation is significant for the occurrence of lightning activity in the next 12 hours. The equation has good promotion and application value.
An analysis is made of the correlation between atmospheric instability parameters and lightning activities in the low latitude plateau region in this paper using the lightning information and radiosonde data in Yunnan Province from 2014 to 2017 Five parameters selected from 9 are strongly correlated. The threshold of lightning occurrence for each parameter is determined by means of the mathematical method. The complex correlation coefficient method is used to calculate the weight of each parameter and set up the prediction equation for lightning potential. Finally, the equation is verified by means of forecasting and case analysis. The results show that the atmospheric instability parameters over the low latitude plateau are sensitive to lightning activities. The response threshold is generally lower than that of the plain area. The prediction effectiveness of the prediction equation is significant for the occurrence of lightning activity in the next 12 hours. The equation has good promotion and application value.
2018, 46(5):1026-1031.
Abstract:
In order to meet the precise needs of the lightning disaster risk decisionmaking and lift the limits of the administrative region for the social and economic data such as population and GDP, the refined spatial distribution of population and GDP in Guizhou Province is analyzed, which is based on the multisource remote sensing data and the statistical yearbooks, so as to achieve the continuous spatial distribution of the victims. The lightning disaster risk assessment model is constructed, and the evaluation factors are selected from the three aspects of disaster factors, disaster environment, and disaster bearing body, combining with lightning location monitoring data, HWSD (Harmonized World Soil Database) data and geographic information data. The results show: (1) The spatial distribution of population and GDP data is gained by modifying the habitat index by integrating slope distribution and retrieving various industrial economic data by integrating land use data and DMSP/OLS night light data. The overall trend and local characteristics are in agreement with the actual situation in Guizhou Province, which can provide a reference for the fine distribution of hazard bodies in the risk assessment of lightning disasters and other natural disasters. (2) The risk of lightning disasters is mainly affected by hazard factors and hazard bearing bodies, which is related to the frequency of lightning activities and the level of social and economic development. The high risk areas in Guizhou Province are mainly in Liupanshui, southeastern Bijie, northeastern Qianxinan, southern and northern Anshun, southeastern Guiyang, southwestern and northeastern Qiannan, northwestern Zunyi, central and southeastern Tongren.
In order to meet the precise needs of the lightning disaster risk decisionmaking and lift the limits of the administrative region for the social and economic data such as population and GDP, the refined spatial distribution of population and GDP in Guizhou Province is analyzed, which is based on the multisource remote sensing data and the statistical yearbooks, so as to achieve the continuous spatial distribution of the victims. The lightning disaster risk assessment model is constructed, and the evaluation factors are selected from the three aspects of disaster factors, disaster environment, and disaster bearing body, combining with lightning location monitoring data, HWSD (Harmonized World Soil Database) data and geographic information data. The results show: (1) The spatial distribution of population and GDP data is gained by modifying the habitat index by integrating slope distribution and retrieving various industrial economic data by integrating land use data and DMSP/OLS night light data. The overall trend and local characteristics are in agreement with the actual situation in Guizhou Province, which can provide a reference for the fine distribution of hazard bodies in the risk assessment of lightning disasters and other natural disasters. (2) The risk of lightning disasters is mainly affected by hazard factors and hazard bearing bodies, which is related to the frequency of lightning activities and the level of social and economic development. The high risk areas in Guizhou Province are mainly in Liupanshui, southeastern Bijie, northeastern Qianxinan, southern and northern Anshun, southeastern Guiyang, southwestern and northeastern Qiannan, northwestern Zunyi, central and southeastern Tongren.
2018, 46(5):1032-1037.
Abstract:
Based on the meteorological factors (light, temperature, and rainfall) and rape yield data from 1990 to 2015, the Key Meteorological Factor Model (KFM), the Climate Suitability Model (CSM) and PTEP (Product of Thermal Effectiveness and PAR) model are used in the simulation and the prediction of rape yields. The results show that: in the backtesting, the fitting effect of PTEP is the best, but CSM does not pass the significant test of 005 levels, while KFM at flowering stage is relatively poor. In the prediction test, the accuracies of all the three models prediction are greater than 90%. The probabilities of the annual prediction accuracy of KFM, CSM and TPM above 95% are 80%, 60% and 80%, respectively. Compared with SRM and CSM, PTEP is more suitable for the forecast service of rape production in Jiangxi Province.
Based on the meteorological factors (light, temperature, and rainfall) and rape yield data from 1990 to 2015, the Key Meteorological Factor Model (KFM), the Climate Suitability Model (CSM) and PTEP (Product of Thermal Effectiveness and PAR) model are used in the simulation and the prediction of rape yields. The results show that: in the backtesting, the fitting effect of PTEP is the best, but CSM does not pass the significant test of 005 levels, while KFM at flowering stage is relatively poor. In the prediction test, the accuracies of all the three models prediction are greater than 90%. The probabilities of the annual prediction accuracy of KFM, CSM and TPM above 95% are 80%, 60% and 80%, respectively. Compared with SRM and CSM, PTEP is more suitable for the forecast service of rape production in Jiangxi Province.
2018, 46(5):1038-1043.
Abstract:
Based on the meteorological data of Yunnan Province from 1981 to 2010, according to the method specified by the construction industry standards and national standards, such 5 building thermal engineering meteorological parameters as climate regions, the number of heating degree days, the number of airconditioning degree days, the average temperature of the coldest month, and the average temperature of the hottest month of 125 towns of Yunnan are calculated. The surface temperature of buildingenvelope thermal bridge and heat transfer coefficient are simulated to provide a practical reference for the architectural design in Yunnan. The results show: in order to improve the precision and practicability of meteorological parameters of buildings, the actual monthly temperature and the climate data of 30 years in all stations of Yunnan should be used; thermal design must satisfy the winter heat preservation requirements in most parts of Yunnan; for thermal bridge, it is essential to choose the building materials with small thermal insulation to prevent condensation phenomenon.
Based on the meteorological data of Yunnan Province from 1981 to 2010, according to the method specified by the construction industry standards and national standards, such 5 building thermal engineering meteorological parameters as climate regions, the number of heating degree days, the number of airconditioning degree days, the average temperature of the coldest month, and the average temperature of the hottest month of 125 towns of Yunnan are calculated. The surface temperature of buildingenvelope thermal bridge and heat transfer coefficient are simulated to provide a practical reference for the architectural design in Yunnan. The results show: in order to improve the precision and practicability of meteorological parameters of buildings, the actual monthly temperature and the climate data of 30 years in all stations of Yunnan should be used; thermal design must satisfy the winter heat preservation requirements in most parts of Yunnan; for thermal bridge, it is essential to choose the building materials with small thermal insulation to prevent condensation phenomenon.
2018, 46(5):1044-1049.
Abstract:
This application is based on the Internet Of Things (IOT) technology, bar codes, twodimension codes, Radio Frequency IDentification (RFID) technology, acoustic photoelectric automatic sensing technology, and GPS/GIS technology to build the IOT management system of weather modification equipment. It is to achieve the entireprocess monitoring of the weather modification equipment and ammunition from production, acceptance, transshipment, warehousing to launch. This project selected four provinces (cities) as the pilot provinces to carry out the application experiment of different technical models according to the active/passive RFID, twodimensional/bar codes, rockets and antiaircraft guns, and different information acquisition technology. The information in accordance with the unified format was collect by the national level system. This project improved the accuracy and timeliness of the weather modification equipment and ammunition information collection; meanwhile, the effective sensors and wireless communication technology were combined to solve automatic data acquisition and realtime monitoring of ground operation information, which improved the level of technology and the modernization of the weather modification information management, being of the reference value to the IOT building of the other provinces.
This application is based on the Internet Of Things (IOT) technology, bar codes, twodimension codes, Radio Frequency IDentification (RFID) technology, acoustic photoelectric automatic sensing technology, and GPS/GIS technology to build the IOT management system of weather modification equipment. It is to achieve the entireprocess monitoring of the weather modification equipment and ammunition from production, acceptance, transshipment, warehousing to launch. This project selected four provinces (cities) as the pilot provinces to carry out the application experiment of different technical models according to the active/passive RFID, twodimensional/bar codes, rockets and antiaircraft guns, and different information acquisition technology. The information in accordance with the unified format was collect by the national level system. This project improved the accuracy and timeliness of the weather modification equipment and ammunition information collection; meanwhile, the effective sensors and wireless communication technology were combined to solve automatic data acquisition and realtime monitoring of ground operation information, which improved the level of technology and the modernization of the weather modification information management, being of the reference value to the IOT building of the other provinces.
2018, 46(5):1050-1054.
Abstract:
The signal surge protective device is a lightning protection device which is widely used in the terminal equipment of signal systems. In order to improve the safety and realize the fault indication function of its components, taking the complexity of the circuit and the limitation of the internal structure space into account, a new signal SPD is designed and studied, using a polymer Positive Temperature Coefficient resistance (PTC) to protect other components, and an integrated fault indicator is added. The simulation tests of overheating protection on TVS (Transient Voltage Suppression) and series resistance, as well as three tests on the impact current, transmission characteristics and overload failure modes in the SPD test standards, are conducted, and the results show that: the new product has the function of thermal protection and all the parameters meet the requirements of the SPD test standards. At the same time, the product has a passive fault indicator, which is suitable for a system that can be interrupted in a short time.
The signal surge protective device is a lightning protection device which is widely used in the terminal equipment of signal systems. In order to improve the safety and realize the fault indication function of its components, taking the complexity of the circuit and the limitation of the internal structure space into account, a new signal SPD is designed and studied, using a polymer Positive Temperature Coefficient resistance (PTC) to protect other components, and an integrated fault indicator is added. The simulation tests of overheating protection on TVS (Transient Voltage Suppression) and series resistance, as well as three tests on the impact current, transmission characteristics and overload failure modes in the SPD test standards, are conducted, and the results show that: the new product has the function of thermal protection and all the parameters meet the requirements of the SPD test standards. At the same time, the product has a passive fault indicator, which is suitable for a system that can be interrupted in a short time.
2018, 46(5):1055-1059.
Abstract:
In this paper， we developed a mobile client providing services for agriculture based on the mobile development platforms of Android and iOS, considering the aspects of the personalized, refined, convenient, and intelligent demands of agrometeorological services in Anhui. It can provide the timebased, subdivisional, and focused meteorological and agricultural integrated information services such as weather forecast, instant messaging service, farmland management, interaction with experts, agricultural information, and so on for agriculturalrelated experts, meteorological information personnel, and agricultural technicians. The platform has been widely used in the threelevel meteorological and agricultural departments of prefectures and counties in Anhui Province to provide intelligent services by combining Internet with meteorology and agriculture.
In this paper， we developed a mobile client providing services for agriculture based on the mobile development platforms of Android and iOS, considering the aspects of the personalized, refined, convenient, and intelligent demands of agrometeorological services in Anhui. It can provide the timebased, subdivisional, and focused meteorological and agricultural integrated information services such as weather forecast, instant messaging service, farmland management, interaction with experts, agricultural information, and so on for agriculturalrelated experts, meteorological information personnel, and agricultural technicians. The platform has been widely used in the threelevel meteorological and agricultural departments of prefectures and counties in Anhui Province to provide intelligent services by combining Internet with meteorology and agriculture.
2018, 46(5):1060-1064.
Abstract:
When an abnormal precipitation record from a regional automatic weather station appears unusually high or historically significant, or greatly larger those of the neighboring stations, the conventional data quality control (QC) method will generally judge it as a suspected case. In this paper, the onsite check method for the situation is described, including the start of the check, the sensor error and instrument performance checking, the assessment of detection environment, and other procedures such as conclusion making and final report forming. An example is used to test the effectiveness and applicability of this method.
When an abnormal precipitation record from a regional automatic weather station appears unusually high or historically significant, or greatly larger those of the neighboring stations, the conventional data quality control (QC) method will generally judge it as a suspected case. In this paper, the onsite check method for the situation is described, including the start of the check, the sensor error and instrument performance checking, the assessment of detection environment, and other procedures such as conclusion making and final report forming. An example is used to test the effectiveness and applicability of this method.
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.