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1.
二等皮托管测风误差分析及偏差模拟计算   总被引:2,自引:0,他引:2  
皮托管是组成风速检定装置的主要计量标准设备,其测量精度对检定质量具有重要影响.从皮托管测风原理出发,详细介绍了影响皮托管测风误差的相关因素,模拟计算了各因素对风速测量产生的影响,分析了影响皮托管测风误差的主要因子.结果表明:温度和阻塞系数是影响二等皮托管测风误差的主要因素.当环境温度偏差为±8℃时,可引起二等皮托管风速测量误差为干0.44 m/s(v=30 m/s).当阻塞修正系数偏差±0.02时,可引起二等皮托管风速测量误差±o.6 m/s(v=30 m/s);皮托管系数、大气压力和湿度经修正后对二等皮托管测风精度影响相对较小.  相似文献   

2.
本文使用中尺度数值模型MM5结合微尺度模型CALMET对黑龙江省桦南地区2009年6月-2010年5月进行风能资源数值模拟,并与测风塔实测风速进行误差对比分析。结果表明各高度模拟风速与实测风相关系数在0.47-0.64,除10 m高度外,年平均风速模拟值都略大于实测值,>10 m/s区间与实测风速频率基本相当,高度越高与实测风速越接近。风向模拟随高度增加趋于稳定,主导风向与实测风向也越接近,70 m高度主导风向与实测风主导风向相一致。模型对风能频率的模拟效果优于对风速频率与风向频率的模拟。  相似文献   

3.
石泉气象站 2 0 0 2 -0 5-1 3 ,EN风极大风速为1 4.4m/s,风向为东风 ,出现时间为 2 0 :1 0 ,最大风速为 1 1 .2 m/s,风向为东南风 ,出现时间2 0 :1 9。 2 1 :0 0风速为 2 .4m/s,风向为西南风 ,2 2 :0 0风速为 2 .2 m/s,风向为西南风。针对此记录有同志提出疑问 :日最大风向风速与相邻正点风向风速相差太大 ,建议该日最大风向风速和极大风向风速按缺测处理。本文从以下几方面判断该记录的正误。1 根据石泉站 EN风多年的使用情况来看 ,没有出现过此类乱码现象 ,感应部分也未出现过风速偏大情况 ,因此应排除仪器故障原因。2 从地面观测的角…  相似文献   

4.
湛江东海岛二月海陆风环流特征研究   总被引:1,自引:0,他引:1  
徐峰  王晶  张羽  张书文  黄克鑫 《气象科学》2012,32(4):423-429
利用2011年2月湛江东海岛风廓线雷达资料,系统分析了湛江东海岛2月平均风场特征及海陆风特征,结果表明:2月湛江东海岛150 m高度处以东偏北出现频率最大,在E、ENE和NE三个方位的风向出现频率之和为66.6%,偏西七个方位的风向出现频率之和仅为1%。以SSW方位为界,偏东风与偏西风的出现频率差异明显。各整点的月平均风速1:00—15:00变化较小,均在1 m/s左右波动;15:00—20:00风速及风速波动都较大,最大值出现在16:00时,为2.1 m/s。2011年2月中只有2日与14日两日符合海陆风日条件,两日共同海风时段为13:00—20:00,持续7 h;陆风时段为2:00—7:00,持续5 h。海风平均风速为2.1 m/s,陆风平均风速为0.8 m/s,海风平均风速明显大于陆风风速。海风与陆风环流垂直高度相差甚小,约1.2 km,风速随高度变化趋势均为先增后减;海风最大风速出现在750 m高度处,陆风出现在500 m高度处,500~750 m高度区间海风环流强度明显强于陆风环流。2 km之上为均匀一致的系统性西风环流。  相似文献   

5.
罗雄光  梁国锋  杨超 《气象科技》2015,43(6):1025-1029
根据广东阳江探空站L波段雷达系统观测的测风资料分析,测风记录用综合探测雷达测风方法与无斜距(或高度替代)测风方法计算的测风量得风层的结果,少数情况下会出现与理论值不相符的现象,两种测风方法计算的结果,有时会超出高空气象观测仪器总体测量准确度要求允许的误差范围。在雷达的仰角小于30°时,量得风层的风速小于3 m/s时,两种测风方法计算量得风层的风速基本相同(误差在允许范围内),但风向有的相差较大,超出测量准确度要求允许的误差范围。当雷达仰角小于15°,量得风层的风速大于30 m/s时,两种测风方法计算量得风层的风向比较接近,但量得风层的风速有的却相差较大,超出测量准确度要求允许的误差范围。  相似文献   

6.
格尔木市区空气污染的气象条件分析   总被引:2,自引:0,他引:2  
利用格尔木市气象台1999~2003年定时风和2005年高空特性层等资料,对年、各代表月及各代表时次的风、大气稳定度等空气污染的气象条件进行了统计分析。结果表明:格尔木市常年盛行W、SW和NW风,年平均风速为2.2m/s;四季的主导风向与年主导风向一致,为W风,春季平均风速最大,秋季最小;年、月平均风速中,风向频率较高的平均风速在1.6~3.1m/s之间,有利于城市污染物的扩散;风向、风速对大气污染的综合影响表现为全年W风污染系数为最大,SE风污染系数为最小;强不稳定、不稳定大气层结在14时出现的频次较高;在大气边界层,一年四季清晨时有不同强度和厚度的辐射逆温存在,使低层大气比较稳定,不利于污染物的扩散。  相似文献   

7.
韩鎏 《陕西气象》2004,(2):19-19
20 0 3年 4月 9日 ,泾阳县气象站遇到一次特殊故障 :风杯转动正常 ,风向风速指示器正常 ,可记录器上风速异常。在观测中 ,瞬时最大风速约1 2 m/s,记录器上 1 0 min平均风速为 9m/s属正常 ,但记录器上 1 0 min平均风速达 1 7m/s,比瞬时风速还大 ,超过历史极值 ,判定仪器故障。将  相似文献   

8.
气象探空火箭测风不确定度评估方法   总被引:2,自引:0,他引:2  
本文在气象火箭测风反演数学模型基础上,通过误差分析理论和曲线拟合最小二乘原理,对大气风场反演结果不确定度的评估方法进行了研究。根据火箭探空仪在空中的运动规律,首先建立数学反演模型,推导得到风速和风向的计算公式;然后根据误差理论,推导得出反演风速和风向的不确定度表达式;基于多项式拟合方法,进一步推导得出拟合后的风速和风向的系统误差和随机误差公式,并求解公式中系数。最后以1次气象火箭实测数据为例,对风场及其不确定度进行了分析计算。结果表明:风速反演不确定度随高度降低而减小,在50~60km高度不确定度约为2.8~3.5m/s,50km以下不确定度在1m/s以内;风向在正北方向(0°)附近摆动时,会导致反演不确定度异常增大,其他高度不确定度基本在10°以内。  相似文献   

9.
奥运会赛艇场馆逐时风场特征   总被引:5,自引:4,他引:1  
应用2007年8月北京奥林匹克水上公园12个自动测风仪逐时风场资料、BJ-ANC对流临近预报系统提供的产品和自动气象站资料等,统计分析了8月奥林匹克赛艇场地的逐时风场各级风的出现频率,同时分析了逐时风速特征和风向特点.结果表明:08:00~18:00,0~2 m/s风速出现的最大频率为82%,出现在08:00;风速在3~5 m/s的最大频率为41%,出现在09:00,次之是15:00频率为36%;风速呈现在6~8 m/s的频率迅速降低,最大仅有14%.大于9 m/s的风速出现频率更小,这种风速一般与强对流天气相对应.BJ-ANC系统的强度产品弱窄带同波,能够预报风向的转变:当弱窄带回波经过奥林匹克水上公周时,有风向转变和风速变化,若两条弱窄带回波碰撞时,雷暴加强,这对奥运赛艇比赛有指导意义.  相似文献   

10.
1961~2010年河北省地面风变化特征及成因探讨   总被引:1,自引:0,他引:1  
利用1961~2010年河北省73个地面气象站风观测资料,结合NCEP/NCAR(2.5°×2.5°)月平均再分析资料和国家气候中心下发的环流指数,采用线性趋势拟合方法,分析地面风速的空间分布以及风速和最大主风向风频的时间变化特征,并对风速减小的成因进行探讨。结果表明:空间上风速呈东北西南向带状分布,依次有大、小、大3个风速带。年平均风速呈减小趋势,减小速率为0.207 m·s-1/10 a;3.0 m/s以下的风速日数呈明显增加趋势,8.0 m/s以上的日数呈显著减小趋势,3.0~8.0 m/s风速的日数没有明显变化趋势。代表站最大主风向为偏南风,最大主风向风频平均每年增加0.54 d。风速的减小与1980年代以后影响我国的环流经向度减小、西风指数增加有关,也与城市化效应的影响有关。  相似文献   

11.
Using the International Comprehensive Ocean-Atmosphere Data Set(ICOADS) and ERA-Interim data, spatial distributions of air-sea temperature difference(ASTD) in the South China Sea(SCS) for the past 35 years are compared,and variations of spatial and temporal distributions of ASTD in this region are addressed using empirical orthogonal function decomposition and wavelet analysis methods. The results indicate that both ICOADS and ERA-Interim data can reflect actual distribution characteristics of ASTD in the SCS, but values of ASTD from the ERA-Interim data are smaller than those of the ICOADS data in the same region. In addition, the ASTD characteristics from the ERA-Interim data are not obvious inshore. A seesaw-type, north-south distribution of ASTD is dominant in the SCS; i.e., a positive peak in the south is associated with a negative peak in the north in November, and a negative peak in the south is accompanied by a positive peak in the north during April and May. Interannual ASTD variations in summer or autumn are decreasing. There is a seesaw-type distribution of ASTD between Beibu Bay and most of the SCS in summer, and the center of large values is in the Nansha Islands area in autumn. The ASTD in the SCS has a strong quasi-3a oscillation period in all seasons, and a quasi-11 a period in winter and spring. The ASTD is positively correlated with the Nio3.4 index in summer and autumn but negatively correlated in spring and winter.  相似文献   

12.
正The Taal Volcano in Luzon is one of the most active and dangerous volcanoes of the Philippines. A recent eruption occurred on 12 January 2020(Fig. 1a), and this volcano is still active with the occurrence of volcanic earthquakes. The eruption has become a deep concern worldwide, not only for its damage on local society, but also for potential hazardous consequences on the Earth's climate and environment.  相似文献   

13.
The moving-window correlation analysis was applied to investigate the relationship between autumn Indian Ocean Dipole (IOD) events and the synchronous autumn precipitation in Huaxi region, based on the daily precipitation, sea surface temperature (SST) and atmospheric circulation data from 1960 to 2012. The correlation curves of IOD and the early modulation of Huaxi region’s autumn precipitation indicated a mutational site appeared in the 1970s. During 1960 to 1979, when the IOD was in positive phase in autumn, the circulations changed from a “W” shape to an ”M” shape at 500 hPa in Asia middle-high latitude region. Cold flux got into the Sichuan province with Northwest flow, the positive anomaly of the water vapor flux transported from Western Pacific to Huaxi region strengthened, caused precipitation increase in east Huaxi region. During 1980 to 1999, when the IOD in autumn was positive phase, the atmospheric circulation presented a “W” shape at 500 hPa, the positive anomaly of the water vapor flux transported from Bay of Bengal to Huaxi region strengthened, caused precipitation ascend in west Huaxi region. In summary, the Indian Ocean changed from cold phase to warm phase since the 1970s, caused the instability of the inter-annual relationship between the IOD and the autumn rainfall in Huaxi region.  相似文献   

14.
Various features of the atmospheric environment affect the number of migratory insects, besides their initial population. However, little is known about the impact of atmospheric low-frequency oscillation(10 to 90 days) on insect migration. A case study was conducted to ascertain the influence of low-frequency atmospheric oscillation on the immigration of brown planthopper, Nilaparvata lugens(Stl), in Hunan and Jiangxi provinces. The results showed the following:(1) The number of immigrating N. lugens from April to June of 2007 through 2016 mainly exhibited a periodic oscillation of 10 to 20 days.(2) The 10-20 d low-frequency number of immigrating N. lugens was significantly correlated with a low-frequency wind field and a geopotential height field at 850 h Pa.(3) During the peak phase of immigration, southwest or south winds served as a driving force and carried N. lugens populations northward, and when in the back of the trough and the front of the ridge, the downward airflow created a favorable condition for N. lugens to land in the study area. In conclusion, the northward migration of N. lugens was influenced by a low-frequency atmospheric circulation based on the analysis of dynamics. This study was the first research connecting atmospheric low-frequency oscillation to insect migration.  相似文献   

15.
The atmospheric and oceanic conditions before the onset of EP El Ni?o and CP El Ni?o in nearly 30 years are compared and analyzed by using 850 hPa wind, 20℃ isotherm depth, sea surface temperature and the Wheeler and Hendon index. The results are as follows: In the western equatorial Pacific, the occurrence of the anomalously strong westerly winds of the EP El Ni?o is earlier than that of the CP El Ni?o. Its intensity is far stronger than that of the CP El Ni?o. Two months before the El Ni?o, the anomaly westerly winds of the EP El Ni?o have extended to the eastern Pacific region, while the westerly wind anomaly of the CP El Ni?o can only extend to the west of the dateline three months before the El Ni?o and later stay there. Unlike the EP El Ni?o, the CP El Ni?o is always associated with easterly wind anomaly in the eastern equatorial Pacific before its onset. The thermocline depth anomaly of the EP El Ni?o can significantly move eastward and deepen. In addition, we also find that the evolution of thermocline is ahead of the development of the sea surface temperature for the EP El Ni?o. The strong MJO activity of the EP El Ni?o in the western and central Pacific is earlier than that of the CP El Ni?o. Measured by the standard deviation of the zonal wind square, the intensity of MJO activity of the EP El Ni?o is significantly greater than that of the CP El Ni?o before the onset of El Ni?o.  相似文献   

16.
基于最新的GTAP8 (Global Trade Analysis Project)数据库,使用投入产出法,分析了2004年到2007年全球贸易变化下南北集团贸易隐含碳变化及对全球碳排放的影响。结果显示,随着发展中国家进出口规模扩张,全球贸易隐含碳流向的重心逐渐向发展中国家转移。2004年到2007年,发达国家高端设备制造业和服务业出口以及发展中国家资源、能源密集型行业及中低端制造业出口的趋势加强,该过程的生产转移导致全球碳排放增长4.15亿t,占研究时段全球贸易隐含碳增量的63%。未来发展中国家的出口隐含碳比重还将进一步提高。贸易变化带来的南北集团隐含碳流动变化对全球应对气候变化行动的影响日益突出,发达国家对此负有重要责任。  相似文献   

17.
正ERRATUM to: Atmospheric and Oceanic Science Letters, 4(2011), 124-130 On page 126 of the printed edition (Issue 2, Volume 4), Fig. 2 was a wrong figure because the contact author made mistake giving the wrong one. The corrected edition has been updated on our website. The editorial office is sincerely sorry for any  相似文献   

18.
19.
Index to Vol.31     
正AN Junling;see LI Ying et al.;(5),1221—1232AN Junling;see QU Yu et al.;(4),787-800AN Junling;see WANG Feng et al.;(6),1331-1342Ania POLOMSKA-HARLICK;see Jieshun ZHU et al.;(4),743-754Baek-Min KIM;see Seong-Joong KIM et al.;(4),863-878BAI Tao;see LI Gang et al.;(1),66-84BAO Qing;see YANG Jing et al.;(5),1147—1156BEI Naifang;  相似文献   

20.
正Journal of Meteorological Research is an international academic journal in atmospheric sciences edited and published by Acta Meteorologica Sinica Press,sponsored by the Chinese Meteorological Society.It has been acting as a bridge of academic exchange between Chinese and foreign meteorologists and aiming at introduction of the current advancements in atmospheric sciences in China.The journal columns include Articles.Note and Correspondence,and research letters.Contributions from all over the world are welcome.  相似文献   

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