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“23.7”华北特大暴雨过程小时强降水时空分布特征

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大气科学学报 2024年第5期47卷 778-788页

作者：唐永兰徐桂荣唐国瑛张文闵爱荣中国气象局武汉暴雨研究所中国气象局流域强降水重点开放实验室/暴雨监测预警湖北省重点实验室湖北武汉430205 三峡国家气候观象台湖北宜昌443099

由于西北太平洋副热带高压、2023年第5号台风“杜苏芮”、第6号台风“卡努”等共同作用,2023年7月29日08时—8月2日08时(北京时)华北地区发生极端特大暴雨,造成了重大社会影响。利用中国气象局国家气象信息中心提供的国家级气象站逐小... 详细信息

由于西北太平洋副热带高压、2023年第5号台风“杜苏芮”、第6号台风“卡努”等共同作用,2023年7月29日08时—8月2日08时(北京时)华北地区发生极端特大暴雨,造成了重大社会影响。利用中国气象局国家气象信息中心提供的国家级气象站逐小时降水资料,分析了此次特大暴雨过程中的小时强降水(Hourly Heavy Rainfall,HHR)时空分布特征,并对不同历时类型强降水事件(Heavy Rainfall Event,HRE)的统计特征进行了对比。结果表明:1)此次特大暴雨HHR强度高、局地性明显,其对总降水量的贡献超过20%,北京西部、河北中部和西南部等太行山东麓为HHR降水量大值区和降水频次活跃区,双台风将水汽源源不断地输送到华北平原,受到太行山等山脉阻挡抬升,利于HHR增幅和持续。2)HHR降水量、降水频次经历6次峰值后减弱,其中第3次峰值时段的HHR降水量最大、降水频次最多、持续时间最长;而在“杜苏芮”残涡螺旋影响、暖式切变线和偏东风影响以及偏南或西南急流影响的3个主要降水阶段中,“杜苏芮”残涡螺旋影响阶段HHR最为活跃,共发生257次HHR,HHR最大降水量达73.5 mm。3)在3种类型HRE中,长历时(>12 h)最多,占比54.5%,短历时(1~6 h)次之,占比32.9%,中历时(7~12 h)最少,占比12.6%;长历时HRE降水量多>180 mm,短历时、中历时HRE的降水量多为[20,60)mm;HRE的最大降水量表现为短历时<中历时<长历时,而最大降水强度表现正相反,3种历时HRE的最大小时降水量多为[20,30)mm。4)不同类型HRE降水量、频次和平均降水强度的空间分布显示,长历时HRE因频次高于短历时和中历时,加之历时长,其降水量也高于后两种类型,北京、河北等地是长历时HRE降水量和频次大值区。

关键词：华北特大暴雨小时强降水强降水事件时空分布台风地形

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Climatological analysis and modeling of the ionospheric global electron content

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Chinese Science Bulletin 2008年第2期53卷 282-288页

作者： SHE ChengLi WAN WeiXing xu guirong Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 China

In this paper, we calculate the ionospheric global electron content (GEC) from the GPS TEC data along the geographic longitude 120°E during the period of 1996-2004, and investigate the relationship be- tween GEC and 10.7 cm solar radio flux F10.7 and its seasonal dependence with partial correlation analysis. Our results show that GEC is closely correlated with solar activity index F10.7 and is also re- lated with annual and semiannual variations. An empirical GEC model driven by those factors is then to examine the influences of different solar activity proxies for the model input. The results suggest that GEC mainly depends on solar activity and the seasonal variations; the latter is also modulated by solar activity. Furthermore, the magnitude of semiannual variation is a little greater than that of annual varia- tion. Our empirical GEC model is proved to be better than the model proposed by Afraimovich et al.

关键词：气候学经验模型电子库容地理学

Applying partial correlation method to analyzing the correlation between ionospheric NmF2 and height of isobaric level in the lower atmosphere

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Chinese Science Bulletin 2007年第17期52卷 2413-2419页

作者： xu guirong WAN WeiXing NING BaiQi Institute of Geoloqy and Geophysics Chinese Academy of Sciences Beijing 100029 China Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

On the basis of a multiple linear regression model performed for ionospheric NmF2, partial correlation method is first applied to investigating the relation between NmF2 and h (the height of isobaric level) in the lower atmosphere over Wuhan, China during 1957―2004. The results show that partial correlation method can eliminate the influences of solar and geomagnetic activities as well as the seasonal varia- tion factors and reveal the true correlation between NmF2 and h in the lower atmosphere. A weak posi- tive correlation between NmF2 and h is found in the middle stratosphere. In addition, by comparing the partial correlation coefficients between NmF2 and its influence factors, we find that NmF2 is mainly affected by solar activity and the seasonal variation factors, and weakly affected by geomagnetic ac- tivity, but hardly affected by h in the lower atmosphere. The study suggests that partial correlation method is a helpful tool for investigating the correlation between ionospheric parameter and its influ- ence factors.

关键词：低层大气偏相关方法线性回归模型电离层

Calibration of the solar radio spectrometer

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Science China(Physics,Mechanics & Astronomy) 2009年第11期52卷 1760-1764页

作者： TAN ChengMing YAN YiHua TAN BaoLin xu guirong Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012China Institute of Heavy Rain China Meteorological AdministrationWuhan 430074China

This paper shows some improvements and new results of calibration of Chinese solar radio spectrometer by analyzing the daily calibration data recorded in the period of 1997-2007. First, the calibration coefficient is fitted for three bands (1.0-2.0 GHz, 2.6-3.8 GHz, 5.2-7.6 GHz) of the spectrometer by using the moving-average method confined by the property of the daily calibration data. By this calibration coefficient, the standard deviation of the calibration result was less than 10 sfu for 95% frequencies of 2.6-3.8 GHz band in 2003. This result is better than that calibrated with the constant coefficient. Second, the calibration coefficient is found in good correlation with local air temperature for most frequencies of 2.6-3.8 GHz band. Moreover, these results are helpful in the research of the quiet solar radio emission.

关键词： solar radio spectrometer calibration coefficient moving-average air temperature correlation

三峡地基遥感垂直观测系统温湿廓线的误差分析与订正方法探讨

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暴雨灾害 2024年第5期43卷 587-597页

作者：张明徐桂荣杜裕叶丹湖北省宜昌市气象局宜昌443000 三峡国家气候观象台宜昌443000 中国气象局武汉暴雨研究所中国气象局流域强降水重点开放实验室/暴雨监测预警湖北省重点实验室武汉430205

三峡地基遥感垂直观测系统是中国气象局“补短板工程”的先行试点,用于监测三峡库区大气垂直廓线的精细结构及演变,其中大气温湿廓线通过微波辐射计反演得到,评估大气温湿廓线的反演偏差并提高其精度对发挥好垂直观测系统在三峡库区的... 详细信息

三峡地基遥感垂直观测系统是中国气象局“补短板工程”的先行试点,用于监测三峡库区大气垂直廓线的精细结构及演变,其中大气温湿廓线通过微波辐射计反演得到,评估大气温湿廓线的反演偏差并提高其精度对发挥好垂直观测系统在三峡库区的精密监测作用具有重要意义。利用2022年11月—2023年6月三峡微波辐射计和同址探空、自动气象站、毫米波测云仪等探测资料,评估了三种天气条件下(晴天、云天、雨天)微波辐射计83个探测高度层温湿度的反演偏差,提出对83个高度层重新分组与探空建立线性回归的微波辐射计温湿度订正方法;评估了订正前后的精度变化并以一次雨雪天气过程的探测结果讨论了订正方法的适用性。结果表明:(1)三种天气条件下微波辐射计和探空温度一致性均较好,多数高度层平均偏差在2℃以内。(2)晴天所有高度层微波辐射计探测湿度均高于探空探测;云天和雨天6 km以上高度层探测湿度均方根误差达30%。(3)高度层重新分组后建立的订正关系能明显提升微波辐射计探测的温湿廓线精度。(4)以一次雨雪天气过程探测为例,订正后的微波辐射计探测的温湿廓线与实况更接近。

关键词：微波辐射计温湿廓线探空偏差订正

Distribution of Rare Earth Elements in Early Permian Reef-Island Ocean Sediments in Eastern Kunlun

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Acta Geologica Sinica(English Edition) 2000年第1期74卷 68-73页

作者： WANG Yongbiao xu guirong LIN Qixiang GONG Shuyun Paleontology Laboratory Faculty of Earth Sciences China University of Geosciences Wuhan 430074 Hubei

Abstract: Based on the study of stratigraphy and fossils, the Early Permian ocean in eastern Kunlun is recognized as a kind of reef-island ocean, in which there exist many different kinds of sediment, including patch carbonate platform, reef facies, transitional facies and deep basin sediments. It has been found that the total contents of REEs increase gradually from carbonate platform facies to deep basin facies. Meanwhile, sediments of different facies have different REE distribution patterns and different Ce anomalies. Most of the sediments of patch carbonate platform facies or reef facies are characterized by extremely negative Ce anomalies or moderately negative Ce anomalies (Ce/Ce*=0.33 to 0.55), and medium or thin-bedded limestones of transitional facies by moderately negative Ce anomalies (Ce/Ce*=0.49 to 0.60). However, sediments of deep basin facies show weak or no negative Ce anomalies (Ce/Ce*=0.69 to 1.47), among which the value of Ce/Ce* in the radiolarian chert is 1.47.

关键词： rare earth elements reef-island ocean Early Permian eastern Kunlun

A Novel On-Site-Real-Time Method for Identifying Characteristic Parameters Using Ultrasonic Echo Groups and Neural Network

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 215-228页

作者： Shuyong Duan Jialin Zhang Heng Ouyang xu Han guirong Liu State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of TechnologyTianjin 300401China Department of Aerospace Engineering and Engineering Mechanics University of CincinnatiCincinnati 45221USA

On-site and real-time non-destructive measurement of elastic constants for materials of a component in a in-service structure is a challenge due to structural complexities,such as ambiguous boundary,variable thickness,nonuniform material *** work develops for the first time a method that uses ultrasound echo groups and artificial neural network(ANN)for reliable on-site real-time identification of material *** use of echo groups allows the use of lower frequencies,and hence more accommodative to structural *** train the ANNs,a numerical model is established that is capable of computing the waveform of ultrasonic echo groups for any given set of material properties of a given *** waveform of an ultrasonic echo groups at an interest location on the surface the structure with material parameters varying in a predefined range are then computed using the numerical *** results in a set of dataset for training the ANN *** the ANN is trained,the material parameters can be identified simultaneously using the actual measured echo waveform as input to the *** tests have been conducted both numerically and experimentally to evaluate the effectiveness and accuracy of the currently proposed *** results show that the maximum identification error of numerical example is less than 2%,and the maximum identification error of experimental test is less than 7%.Compared with currently prevailing methods and equipment,the proposefy the density and thickness,in addition to the elastic ***,the reliability and accuracy of inverse prediction is significantly ***,it has broad applications and enables real-time field measurements,which has not been fulfilled by any other available methods or equipment.

关键词： Parameter identification Ultrasonic echo group High-precision modeling Artificial neural network NDT

Analysis of the Characteristics of the Low-level Jets in the Middle Reaches of the Yangtze River during the Mei-yu Season

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Advances in Atmospheric Sciences 2023年第4期40卷 711-724页

作者： Chunguang CUI Wen ZHOU Hao YANG Xiaokang WANG Yi DENG Xiaofang WANG guirong xu Jingyu WANG Institute of Heavy Rain China Meteorological AdministrationHubei Key Laboratory for Heavy Rain Monitoring and Warning ResearchWuhan 430205China School of Earth and Atmospheric Sciences Georgia Institute of TechnologyAtlanta 30314USA

Here,we analyze the characteristics and the formation mechanisms of low-level jets(LLJs)in the middle reaches of the Yangtze River during the 2010 mei-yu season using Wuhan station radiosonde data and the fifth generation of the European Centre for Medium-Range Weather Forecasts(ERA5)reanalysis *** results show that the vertical structure of LLJs is characterized by a predominance of boundary layer jets(BLJs)concentrated at heights of 900-1200 *** BLJs occur most frequently at 2300 LST(LST=UTC+8 hours)but are strongest at 0200 LST,with composite wind velocities>14 m s^(-1).Synoptic-system-related LLJs(SLLJs)occur most frequently at 0800 LST but are strongest at 1100LST,with composite wind velocities>12 m s^(-1).Both BLJs and SLLJs are characterized by a southwesterly wind direction,although the wind direction of SLLJs is more westerly,and northeasterly SLLJs occur more frequently than northeasterly *** Wuhan is south of the mei-yu front,the westward extension of the northwest Pacific subtropical high intensifies,and the low-pressure system in the eastern Tibetan Plateau strengthens,favoring the formation of LLJs,which are closely related to *** wind speeds on rainstorm days are greater than those on LLJ *** analysis of four typical heavy precipitation events shows the presence of LLJs at the center of the precipitation and on its southern side before the onset of heavy *** were shown to develop earlier than SLLJs.

关键词： mei-yu front boundary layer jets synoptic low-level jets heavy rainfall middle reaches of the Yangtze River

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青藏高原东侧九龙夏季非降水云的观测特征

暴雨灾害 2024年第2期43卷 135-145页

作者：徐桂荣王晓芳万蓉李平李雨生王俊超中国气象局武汉暴雨研究所中国气象局流域强降水重点开放实验室/暴雨监测预警湖北省重点实验室武汉430205 四川省气象探测数据中心成都610072 高原与盆地暴雨旱涝灾害四川省重点实验室成都610072 杭州浅海科技有限责任公司杭州310056

青藏高原东侧九龙地区是西南涡多发区,利用该地区新型探测设备开展云探测,有助于增强对西南涡多发区云特征的认识。利用2018—2019年6—8月九龙站地基微波辐射计资料,分析了该地区夏季非降水云的出现率、液态水路径及过冷水路径的观测... 详细信息

青藏高原东侧九龙地区是西南涡多发区,利用该地区新型探测设备开展云探测,有助于增强对西南涡多发区云特征的认识。利用2018—2019年6—8月九龙站地基微波辐射计资料,分析了该地区夏季非降水云的出现率、液态水路径及过冷水路径的观测特征。结果表明:九龙夏季非降水云出现率月均值在67%~82%之间,以低云和中云为主,高云较少;低云出现率表现为白天低、夜间高,而中云和高云则相反;云出现率的垂直分布表现为单峰形态,在约2km高度存在云出现率峰值8.1%;受大气热力层结日变化影响,云出现率的单峰垂直分布呈现日夜差异。另外,九龙夏季非降水云的液态水路径均值为0.433kg·m^(-2),其中低云、中云、高云的液态水路径均值分别为0.665、0.240、0.102kg·m^(-2);低云的液态水路径日变化特征与其出现率相似,而中云和高云的液态水路径日变化特征不明显。此外,九龙夏季非降水云中冷云的过冷水路径均值为0.154kg·m^(-2),其中低云、中云、高云的过冷水路径均值分别为0.065、0.166、0.102kg·m^(-2);总体上过冷水路径在液态水路径中的占比约为34.3%~38.8%,过冷水路径占比随云的高度而增大,这使得中云和高云的过冷水路径日变化与其液态水路径相似。与同纬度华中地区相比,九龙夏季非降水云具有明显不同的特征,这与两地之间的大气水汽特征差异密切相关。

关键词：青藏高原西南涡非降水云云出现率液态水路径过冷水路径

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