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基于GPRS多要素农业气象自动站一般安装在郊外旷野,由于自动气象站本身集合了传感器、数据采集器和数据通信器等敏感性较强的弱电设备,很容易遭受雷电损坏。文章通过分析基于GPRS多要素农业气象自动站遭受雷击损坏的原因,从直击雷、闪电静电感应、闪电电磁感应、综合布线和地电位反击上提出了相应的雷电防护措施,为自动气象站安装人员整改、维护人员提供一个参考。 相似文献
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经验正交分解方法是气象上常用的方法,其优点在于能反映要素场的主要特征,对空间点位置不作要求,既可取同一要素不同站点、又可取同一站点不同要素进行分解。本文利用经验正交分解法,分析了张掖地区降水、气温的空间分布特征,为改进县站预报方法,为地区台制作全区分片预报提供依据。临泽站因建站迟取1967—1986年20年资料,其余各站取1951一1980年30年资料。一、降水、气温空间分布的一般特征 相似文献
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船舶雷电防护技术研究 总被引：1，自引：0，他引：1
为了能够科学合理地为大型复杂的船体进行雷电防护设计,文章依据雷电形成的过程及特点,分析总结船舶遭受雷电危害可能存在两方面的原因：一种是船舶直接接闪雷电流;另一方面是雷电没有直接击中船舶,而是雷击电磁脉冲对船舶造成的间接影响。最后文章从船舶本身的特殊性出发,提出安装接闪器、引下线和泄流装置的方法防止雷电对船舶造成的直接危害,提出采取等电位连接、屏蔽、接地和安装电涌保护器的方法减少船舶遭受雷电的间接影响,并考虑船舶所处工作大环境提出防护建议。只有合理地采用各种防护措施才能最大限度地避免船舶遭受雷电干扰。 相似文献
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介绍4要素区域自动气象站设备的维护和维修方法,为进一步完善中小尺度自动气象观测网,保证4要素自动站顺利运行提供参考依据。 相似文献
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日本气象研究所曾对安装在某孤岛上作为对地静止气象卫星的资料收集系统的全自动天气站的实际模型进行了试验。有两类资料收集平台:一是船舶,飘移浮标站及运载气球系统等国际自动观测平台;二是陆地自动站与固定浮标站的单独自动观测平台。本文所介绍的是陆地全自动天气站。该系统主要设计要求是:1.将耗电量减到最小,以便能够使用容量最小的电池。2.使维修间隔保持在一年以上。3.造价低。一、气象仪器观测项目及精度如表1所示。除了雨量器和气压表外,所有的仪器全部安装在6米高的塔上,无线电装置及其天线也应安装在塔的附近。7分贝增益的9圈螺旋形天线的长度为200厘米,直径24厘米。 相似文献
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短中期降水温度天气过程区域分布的研究 总被引：2，自引：0，他引：2
运用旋转主分量方法对分布于全国621个站点的候降水量和2214个站的逐日最高最低气温进行分析。得到4个季节的降水气温主特征模态及其相对应的时间变率。分析结果表明，该方法所分解得到的特征模态较好地反映了全国不同区域降水温度演变的差别，依据各模态的相关系数将全国划分为不同的降水温度天气区。最后。获得表征全国不同天气特点的252个代表站，这些站的资料可作为提高要素客观预报、扩展服务领域的基本资料。 相似文献
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土壤水分条件对冬小麦生长发育及产量构成影响研究 总被引：2，自引：0，他引：2
通过2011-2013年中国气象局固城生态环境与农业气象试验站冬小麦种植试验,利用冬小麦不同生育期土壤湿度、根长密度、株高、绿叶面积和产量等资料,研究不同土壤水分条件对河北固城冬小麦生长发育和产量构成的影响。结果表明：2011-2012年固城站冬小麦0-50 cm土壤相对湿度>50%为冬小麦适宜土壤湿度。2012-2013年固城站冬小麦各生育期0-80 cm土壤相对湿度<55%时,尽管80-120 cm土壤相对湿度为55%-80%,但冬小麦根系和产量构成要素均较小。冬小麦各生育期0-80 cm土壤相对湿度为55%-70%时,冬小麦根系总量最多,则冬小麦生长发育最好,产量构成要素均较好,总产量最高。冬小麦各生育期0-120 cm土壤相对湿度<55%时,冬小麦根系总量最小,且根系集中分布的深度也较浅,总产量最小。冬小麦各生育期0-120 cm土壤相对湿度>80%时,冬小麦根系总量较多,但总体产量比0-80 cm土壤相对湿度为55%-70%时低。 相似文献
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The spatial and temporal variations of daily maximum temperature(Tmax), daily minimum temperature(Tmin), daily maximum precipitation(Pmax) and daily maximum wind speed(WSmax) were examined in China using Mann-Kendall test and linear regression method. The results indicated that for China as a whole, Tmax, Tmin and Pmax had significant increasing trends at rates of 0.15℃ per decade, 0.45℃ per decade and 0.58 mm per decade,respectively, while WSmax had decreased significantly at 1.18 m·s~(-1) per decade during 1959—2014. In all regions of China, Tmin increased and WSmax decreased significantly. Spatially, Tmax increased significantly at most of the stations in South China(SC), northwestern North China(NC), northeastern Northeast China(NEC), eastern Northwest China(NWC) and eastern Southwest China(SWC), and the increasing trends were significant in NC, SC, NWC and SWC on the regional average. Tmin increased significantly at most of the stations in China, with notable increase in NEC, northern and southeastern NC and northwestern and eastern NWC. Pmax showed no significant trend at most of the stations in China, and on the regional average it decreased significantly in NC but increased in SC, NWC and the mid-lower Yangtze River valley(YR). WSmax decreased significantly at the vast majority of stations in China, with remarkable decrease in northern NC, northern and central YR, central and southern SC and in parts of central NEC and western NWC. With global climate change and rapidly economic development, China has become more vulnerable to climatic extremes and meteorological disasters, so more strategies of mitigation and/or adaptation of climatic extremes,such as environmentally-friendly and low-cost energy production systems and the enhancement of engineering defense measures are necessary for government and social publics. 相似文献
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Observed daily precipitation data from the National Meteorological Observatory in Hainan province and daily data from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis-2 dataset from 1981 to 2014 are used to analyze the relationship between Hainan extreme heavy rainfall processes in autumn (referred to as EHRPs) and 10–30 d low-frequency circulation. Based on the key low-frequency signals and the NCEP Climate Forecast System Version 2 (CFSv2) model forecasting products, a dynamical-statistical method is established for the extended-range forecast of EHRPs. The results suggest that EHRPs have a close relationship with the 10–30 d low-frequency oscillation of 850 hPa zonal wind over Hainan Island and to its north, and that they basically occur during the trough phase of the low-frequency oscillation of zonal wind. The latitudinal propagation of the low-frequency wave train in the middle-high latitudes and the meridional propagation of the low-frequency wave train along the coast of East Asia contribute to the ‘north high (cold), south low (warm)’ pattern near Hainan Island, which results in the zonal wind over Hainan Island and to its north reaching its trough, consequently leading to EHRPs. Considering the link between low-frequency circulation and EHRPs, a low-frequency wave train index (LWTI) is defined and adopted to forecast EHRPs by using NCEP CFSv2 forecasting products. EHRPs are predicted to occur during peak phases of LWTI with value larger than 1 for three or more consecutive forecast days. Hindcast experiments for EHRPs in 2015–2016 indicate that EHRPs can be predicted 8–24 d in advance, with an average period of validity of 16.7 d. 相似文献
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Based on the measurements obtained at 64 national meteorological stations in the Beijing–Tianjin–Hebei (BTH) region between 1970 and 2013, the potential evapotranspiration (ET0) in this region was estimated using the Penman–Monteith equation and its sensitivity to maximum temperature (Tmax), minimum temperature (Tmin), wind speed (Vw), net radiation (Rn) and water vapor pressure (Pwv) was analyzed, respectively. The results are shown as follows. (1) The climatic elements in the BTH region underwent significant changes in the study period. Vw and Rn decreased significantly, whereas Tmin, Tmax and Pwv increased considerably. (2) In the BTH region, ET0 also exhibited a significant decreasing trend, and the sensitivity of ET0 to the climatic elements exhibited seasonal characteristics. Of all the climatic elements, ET0 was most sensitive to Pwv in the fall and winter and Rn in the spring and summer. On the annual scale, ET0 was most sensitive to Pwv, followed by Rn, Vw, Tmax and Tmin. In addition, the sensitivity coefficient of ET0 with respect to Pwv had a negative value for all the areas, indicating that increases in Pwv can prevent ET0 from increasing. (3) The sensitivity of ET0 to Tmin and Tmax was significantly lower than its sensitivity to other climatic elements. However, increases in temperature can lead to changes in Pwv and Rn. The temperature should be considered the key intrinsic climatic element that has caused the "evaporation paradox" phenomenon in the BTH region. 相似文献
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Storms that occur at the Bay of Bengal (BoB) are of a bimodal pattern, which is different from that of the other sea areas. By using the NCEP, SST and JTWC data, the causes of the bimodal pattern storm activity of the BoB are diagnosed and analyzed in this paper. The result shows that the seasonal variation of general atmosphere circulation in East Asia has a regulating and controlling impact on the BoB storm activity, and the “bimodal period” of the storm activity corresponds exactly to the seasonal conversion period of atmospheric circulation. The minor wind speed of shear spring and autumn contributed to the storm, which was a crucial factor for the generation and occurrence of the “bimodal pattern” storm activity in the BoB. The analysis on sea surface temperature (SST) shows that the SSTs of all the year around in the BoB area meet the conditions required for the generation of tropical cyclones (TCs). However, the SSTs in the central area of the bay are higher than that of the surrounding areas in spring and autumn, which facilitates the occurrence of a “two-peak” storm activity pattern. The genesis potential index (GPI) quantifies and reflects the environmental conditions for the generation of the BoB storms. For GPI, the intense low-level vortex disturbance in the troposphere and high-humidity atmosphere are the sufficient conditions for storms, while large maximum wind velocity of the ground vortex radius and small vertical wind shear are the necessary conditions of storms. 相似文献
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Yuepeng PAN Mengna GU Yuexin HE Dianming WU Chunyan LIU Linlin SONG Shili TIAN Xuemei Lü Yang SUN Tao SONG Wendell W. WALTERS Xuejun LIU Nicholas A. MARTIN Qianqian ZHANG Yunting FANG Valerio FERRACCI Yuesi WANG 《大气科学进展》2020,37(9):933-938
正While China’s Air Pollution Prevention and Control Action Plan on particulate matter since 2013 has reduced sulfate significantly, aerosol ammonium nitrate remains high in East China. As the high nitrate abundances are strongly linked with ammonia, reducing ammonia emissions is becoming increasingly important to improve the air quality of China. Although satellite data provide evidence of substantial increases in atmospheric ammonia concentrations over major agricultural regions, long-term surface observation of ammonia concentrations are sparse. In addition, there is still no consensus on 相似文献
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《大气和海洋科学快报》2014,7(6):F0003-F0003
AIMS AND SCOPE
Atmospheric and Oceanic Science Letters （AOSL） publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. Contributions from all over the world are welcome. 相似文献
Atmospheric and Oceanic Science Letters （AOSL） publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. Contributions from all over the world are welcome. 相似文献
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《大气和海洋科学快报》2014,(5):F0003-F0003
AIMS AND SCOPE Atmospheric and Oceanic Science Letters （AOSL） pub- lishes short research letters on all disciplines of the atmos- phere sciences and physical oceanography. Contributions from all over the world are welcome. 相似文献
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《大气科学进展》2014,(6)
正Aims Scope Advances in Atmospheric Sciences(AAS)is an international journal on the dynamics,physics,and chemistry of the atmosphere and ocean with papers across the full range of the atmospheric sciences,co-published bimonthly by Science Press and Springer.The journal includes Articles,Note and Correspondence,and Letters.Contributions from all over the world are welcome. 相似文献
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DING Yihui WU Guoxiong Da-Lin ZHANG ZHANG Renhe Co-Chief Editors 《Acta Meteorologica Sinica》2014,28(5):669-670
As we will soon celebrate the 90th anniversary of the founding of the Chinese Meteorological Society （CMS）,Acta Meteorologica Sinica （AMS）,which was originally named as Bulletin of the Chinese Meteorological Society,has gone through 89 years of development and excitement since her first issue in July 1925.According to archived documents （CMS Editorial Committee,1925）,AMS was founded to report the research findings of Chinese meteorologists,record their recommendations for improving meteorological services,and share their common meteorological interests in order to promote the growth of AMS such that more members could be inspired to conduct atmospheric research and meteorological knowledge would be better disseminated to and benefit the general public.By upholding and carrying forward this purpose,AMS has published many highly valuable scientific papers.Some could be treated as classical articles,which have produced important influences on both domestic and international meteorological communities and the related fields. 相似文献