High-vertical-resolution radiosonde wind data are highly valuable for describing the dynamics of the meso-and microscale atmosphere. However, the current algorithm used in China's L-band radar sounding system for ...High-vertical-resolution radiosonde wind data are highly valuable for describing the dynamics of the meso-and microscale atmosphere. However, the current algorithm used in China's L-band radar sounding system for calculating highvertical-resolution wind vectors excessively smooths the data, resulting in significant underestimation of the calculated kinetic energy of gravity waves compared to similar products from other countries, which greatly limits the effective utilization of the data. To address this issue, this study proposes a novel method to calculate high-vertical-resolution wind vectors that utilizes the elevation angle, azimuth angle, and slant range from L-band radar. In order to obtain wind data with a stable quality, a two-step automatic quality control procedure, including the RMSE-F(root-mean-square error F) test and elemental consistency test are first applied to the slant range data, to eliminate continuous erroneous data caused by unstable signals or radar malfunctions. Then, a wind calculation scheme based on a sliding second-order polynomial fitting is utilized to derive the high-vertical-resolution radiosonde wind vectors. The evaluation results demonstrate that the wind data obtained through the proposed method show a high level of consistency with the high-resolution wind data observed using the Vaisala Global Positioning System and the data observed by the new Beidou Navigation Sounding System. The calculation of the kinetic energy of gravity waves in the recalculated wind data also reaches a level comparable to the Vaisala observations.展开更多
To determine the performance and data accuracy of the 50 MHz Beijing Mesosphere-Stratosphere-Troposphere （MST） radar, comparisons of radar measured horizontal winds in the height range 3-25 km with radiosonde observ...To determine the performance and data accuracy of the 50 MHz Beijing Mesosphere-Stratosphere-Troposphere （MST） radar, comparisons of radar measured horizontal winds in the height range 3-25 km with radiosonde observations were made during 2012. A total of 427 profiles and 15 210 data pairs were compared. There was very good agreement between the two types of measurement. Standard deviations of difference （mean difference） for wind direction, wind speed, zonal wind and meridional wind were 24.86° （0.77°）, 3.37 （-0.44）, 3.33 （-0.32） and 3.58 （-0.25） m s^-1, respectively. The annual standard deviations of differences for wind speed were within 2.5-3 m s^-1 at all heights apart from 10-15 km, the area of strong winds, where the values were 3-4 m s^-1. The relatively larger differences were mainly due to wind field variations in height regions with larger wind speeds, stronger wind shear and the quasi-zero wind layer. A lower MST radar SNR and a lower percentage of data pairs compared will also result in larger inconsistencies. Importantly, this study found that differences between the MST radar and radiosonde observations did not simply increase when balloon drift resulted in an increase in the real-time distance between the two instruments, but also depended on spatiotemporal structures and their respective positions in the contemporary synoptic systems. In this sense, the MST radar was shown to be a unique observation facility for atmospheric dynamics studies, as well as an operational meteorological observation system with a high temporal and vertical resolution.展开更多
The first troposphere wind profiling radar in China has been in operation. The paper describes the radar parameters and characteristics with some experimental results presented.
Horizontal wind measured by wind profiling radar(WPR) is based on uniform wind assumption in volume of lateral beam. However, this assumption cannot completely meet in the real atmosphere. The subject of this work is ...Horizontal wind measured by wind profiling radar(WPR) is based on uniform wind assumption in volume of lateral beam. However, this assumption cannot completely meet in the real atmosphere. The subject of this work is to analyze the influence of atmospheric inhomogeneities for wind measurement. Five-beam WPR can measure two groups of horizontal wind components U and V independently, using the difference of horizontal wind components U and V can evaluate the influence of the inhomogeneity of the atmospheric motion on wind measurement. The influences can be divided into both inhomogeneous distribution of horizontal motion and vertical motion. Based on wind measurements and meteorological background information, a new means of coordinate rotation the two kinds of inhomogeneous factor was separated, and the impact in different weather background was discussed. From analysis of the wind measured by type of PB-II WPR(445MHz) during 2012 at Yanqing of Beijing, it is shown that the inhomogeneity of horizontal motion is nearly the same in U and V direction. Both the inhomogeneities of horizontal motion and vertical motion have influence on wind measurement, and the degrees of both influences are associated with changes of wind speed. In clear air, inhomogeneity of horizontal motion is the main influence on wind measurement because of small vertical velocity.In precipitation, the two influences are larger than that in clear air.展开更多
[目的]文章旨在研究空中风力发电系统(Airborne Wind Energy System,AWES)的测风需求及设备选型。[方法]以某空中风力发电示范工程为依托,开展测风激光雷达与风廓线雷达的对比观测试验,并对数据获取率、垂直廓线特征和时间变化特征进行...[目的]文章旨在研究空中风力发电系统(Airborne Wind Energy System,AWES)的测风需求及设备选型。[方法]以某空中风力发电示范工程为依托,开展测风激光雷达与风廓线雷达的对比观测试验,并对数据获取率、垂直廓线特征和时间变化特征进行分析。[结果]结果显示:在3 km高度范围内,测风激光雷达的数据获取率随高度递减至不足0.4,风廓线雷达的数据获取率则维持在0.98以上,具有更好的观测适应性;两种测风设备的风速、风向垂直廓线以及逐日、多日波动特征均具有一致性,并且能被再分析资料和高空气象站同期探空资料所验证。测风激光雷达观测结果的中位数、极差、标准差等统计特征与再分析资料更接近,相关性更好;风廓线雷达观测结果的极差和标准差整体偏大,测风精度不及测风激光雷达。[结论]文章研究表明,应根据项目所在地的气候状况,在空中风力发电站工程的不同设计阶段合理选择测风设备,科学设置测风方式。展开更多
基金funded by an NSFC Major Project (Grant No. 42090033)the China Meteorological Administration Youth Innovation Team “High-Value Climate Change Data Product Development and Application Services”(Grant No. CMA2023QN08)the National Meteorological Information Centre Surplus Funds Program (Grant NMICJY202310)。
文摘High-vertical-resolution radiosonde wind data are highly valuable for describing the dynamics of the meso-and microscale atmosphere. However, the current algorithm used in China's L-band radar sounding system for calculating highvertical-resolution wind vectors excessively smooths the data, resulting in significant underestimation of the calculated kinetic energy of gravity waves compared to similar products from other countries, which greatly limits the effective utilization of the data. To address this issue, this study proposes a novel method to calculate high-vertical-resolution wind vectors that utilizes the elevation angle, azimuth angle, and slant range from L-band radar. In order to obtain wind data with a stable quality, a two-step automatic quality control procedure, including the RMSE-F(root-mean-square error F) test and elemental consistency test are first applied to the slant range data, to eliminate continuous erroneous data caused by unstable signals or radar malfunctions. Then, a wind calculation scheme based on a sliding second-order polynomial fitting is utilized to derive the high-vertical-resolution radiosonde wind vectors. The evaluation results demonstrate that the wind data obtained through the proposed method show a high level of consistency with the high-resolution wind data observed using the Vaisala Global Positioning System and the data observed by the new Beidou Navigation Sounding System. The calculation of the kinetic energy of gravity waves in the recalculated wind data also reaches a level comparable to the Vaisala observations.
基金supported by National Natural Science Foundation of China(NSFC Project No.41127901)the Chinese Meridian Project
文摘To determine the performance and data accuracy of the 50 MHz Beijing Mesosphere-Stratosphere-Troposphere （MST） radar, comparisons of radar measured horizontal winds in the height range 3-25 km with radiosonde observations were made during 2012. A total of 427 profiles and 15 210 data pairs were compared. There was very good agreement between the two types of measurement. Standard deviations of difference （mean difference） for wind direction, wind speed, zonal wind and meridional wind were 24.86° （0.77°）, 3.37 （-0.44）, 3.33 （-0.32） and 3.58 （-0.25） m s^-1, respectively. The annual standard deviations of differences for wind speed were within 2.5-3 m s^-1 at all heights apart from 10-15 km, the area of strong winds, where the values were 3-4 m s^-1. The relatively larger differences were mainly due to wind field variations in height regions with larger wind speeds, stronger wind shear and the quasi-zero wind layer. A lower MST radar SNR and a lower percentage of data pairs compared will also result in larger inconsistencies. Importantly, this study found that differences between the MST radar and radiosonde observations did not simply increase when balloon drift resulted in an increase in the real-time distance between the two instruments, but also depended on spatiotemporal structures and their respective positions in the contemporary synoptic systems. In this sense, the MST radar was shown to be a unique observation facility for atmospheric dynamics studies, as well as an operational meteorological observation system with a high temporal and vertical resolution.
文摘The first troposphere wind profiling radar in China has been in operation. The paper describes the radar parameters and characteristics with some experimental results presented.
基金National Natural Science Foundation of China(41475029)China Meteorological Administration Special Public Welfare Research Fund(GYHY201306004)Meteorological Key Technology Integration and Application of the China Meteorological Administration(CMAGJ2013M74)
文摘Horizontal wind measured by wind profiling radar(WPR) is based on uniform wind assumption in volume of lateral beam. However, this assumption cannot completely meet in the real atmosphere. The subject of this work is to analyze the influence of atmospheric inhomogeneities for wind measurement. Five-beam WPR can measure two groups of horizontal wind components U and V independently, using the difference of horizontal wind components U and V can evaluate the influence of the inhomogeneity of the atmospheric motion on wind measurement. The influences can be divided into both inhomogeneous distribution of horizontal motion and vertical motion. Based on wind measurements and meteorological background information, a new means of coordinate rotation the two kinds of inhomogeneous factor was separated, and the impact in different weather background was discussed. From analysis of the wind measured by type of PB-II WPR(445MHz) during 2012 at Yanqing of Beijing, it is shown that the inhomogeneity of horizontal motion is nearly the same in U and V direction. Both the inhomogeneities of horizontal motion and vertical motion have influence on wind measurement, and the degrees of both influences are associated with changes of wind speed. In clear air, inhomogeneity of horizontal motion is the main influence on wind measurement because of small vertical velocity.In precipitation, the two influences are larger than that in clear air.
文摘[目的]文章旨在研究空中风力发电系统(Airborne Wind Energy System,AWES)的测风需求及设备选型。[方法]以某空中风力发电示范工程为依托,开展测风激光雷达与风廓线雷达的对比观测试验,并对数据获取率、垂直廓线特征和时间变化特征进行分析。[结果]结果显示:在3 km高度范围内,测风激光雷达的数据获取率随高度递减至不足0.4,风廓线雷达的数据获取率则维持在0.98以上,具有更好的观测适应性;两种测风设备的风速、风向垂直廓线以及逐日、多日波动特征均具有一致性,并且能被再分析资料和高空气象站同期探空资料所验证。测风激光雷达观测结果的中位数、极差、标准差等统计特征与再分析资料更接近,相关性更好;风廓线雷达观测结果的极差和标准差整体偏大,测风精度不及测风激光雷达。[结论]文章研究表明,应根据项目所在地的气候状况,在空中风力发电站工程的不同设计阶段合理选择测风设备,科学设置测风方式。
