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1.
影响铜仁地区水稻生产的气象灾害分析   总被引:3,自引:0,他引:3  
根据1967-1996年铜仁地区近30年气象资料,分析了影响其水稻生产的几种主要气象灾害发生的频率,趋势及对其水稻生产的危害程度,得出:60年代后期到70年代,旱灾,水灾危害相对较轻;80年代各种灾害性天气频敏发生,其中尤以夏旱对水稻生产危害最为严重,进入90年代,夏旱危害呈下降趋势,水涝危害呈上升趋势,倒春寒对水稻生产的危害相对对较小,并就此提出了减灾措施。  相似文献   

2.
由雷电流产生危害的方式出发,从暂态电位抬高、回路感应过电压、线路感应过电压、耦合过电压四个方面进行详细分析,明确了雷电流产生危害的起因及形式,阐明了雷电对建筑物内电子设备危害的具体原因及危害原理,为如何做好雷电防护提供技术基础。  相似文献   

3.
雷电的危害及预防措施   总被引:2,自引:0,他引:2  
分析雷电对建筑物和设备的危害,提出对雷电危害的预防措施.  相似文献   

4.
2012年《联合国气候变化框架公约》(简称《公约》)多哈会议期间,应对气候变化不利影响的损失与危害问题突然升温,成为影响大会能否成功的关键议题之一。通过回顾《公约》下损失与危害问题谈判的背景历程,对主要集团的观点和核心问题进行了分析,认为发达国家出于自身利益考虑,弱化《公约》下承担的历史责任,甚至向发展中国家转嫁责任,是损失与危害谈判进展缓慢的根本原因。并提出在2013年第十九次缔约方大会(COP19)上损失与危害谈判中,发展中国家需要坚持损失与危害议题的本质是要求发达国家承担历史责任,坚决抵制责任转嫁;损失与危害谈判必须加强发展中国家的团结,必须清醒地认识到让部分发展中大国承担出资义务是不公平的要求;确保损失与危害国际机制具备活动组织、资金来源、效果评估与报告等一系列核心职能,以争取损失与危害议题谈判取得成功。  相似文献   

5.
后季稻抽穗期的低温危害,是造成后季稻产量不稳不高的重要原因。六十年代以来,我国农业气象工作者对后季稻抽穗扬花期的秋季低温危害规律,做了不少试验研究工作,取得了一定成绩。但长期以来未能得出较确切和客观的低温危害指标。为了解决这一问题,我们从现有条件出发,于1977年在浙江天目山地区进行了一次水稻抽穗开花期低温危害的试验。  相似文献   

6.
利用焦作市植保部门10多年来的棉铃虫发生危害调查资料,分析了1992~1995年棉铃虫发生危害的新特点,从气象条件、种植结构、品种布局、生态环境、天敌数量、人为因素等方面揭示了影响棉铃虫发生危害变化的原因,并提出了防治措施。  相似文献   

7.
渔业气象灾害是不利的气象条件给渔业生产造成的危害。气象条件对渔业生产的危害分为两大类,一类直接危害渔业生物的生理活动,另一类通过影响渔业生物栖息的水环境,间接地造成危害。在渔业生产上,可以采取相应措施防治渔业气象灾害。  相似文献   

8.
气候变暖对获嘉县农作物病虫害发生流行的影响   总被引:1,自引:0,他引:1  
温度升高,将有利于一些病虫害的发生、越冬、危害,有些病虫害将有严重发生和危害加重的趋势。  相似文献   

9.
中国生态气象灾害研究   总被引:2,自引:1,他引:1       下载免费PDF全文
综述了生态气象灾害的定义、类型与特点;7种主要生态气象灾害的危害特征,包括危害现状、发展趋势以及主要危害;气象因子对7种主要生态气象灾害的影响;生态气象灾害的监测、预警与评估;生态气象灾害的应急管理与防御措施和恢复重建技术等5个重要方面的内容。生态气象灾害是我国一种综合性的、重大的自然灾害,其危害特点:具有累积性与长期性、难恢复性和不可抗逆性。它不仅直接危害到生态系统本身的健康,使生态系统严重恶化,还极大地危害到人类赖以生存的物质基础,最终严重地制约了社会经济可持续发展。生态气象灾害是一门多学科交叉、新型而又重要的领域。  相似文献   

10.
80年代初,我国南方水稻区对籼型杂交稻秋季低温危害的农业气象指标研究表明,低温指标的区域性很强,即使同一品种,生态条件不一样,低温危害指标亦不一样。十多年的实践证明,即使同一低温指标,年际间危害程度亦大不相同。本文试图以温黄平原二县一市资料,统计分析历年来秋季低温对产量的影响程度,提出了秋季低温危害的气候指标,为合理安排播期提供依据。  相似文献   

11.
叶茵  余清 《贵州气象》2004,28(4):37-38
我局从1999~2003年,测报工作连续4年未出现错情,在此期间共有1个250个班,9个百班无错通过上级业务部门验收.在仪器保管、使用、维护上符合要求,对外报送的各种表、簿都能做好出门合格.  相似文献   

12.
13.
The impact of high resolution modern vegetation cover on the West African climate is examined using the International Centre for Theoretical Physics Regional Climate Model implementing the NCAR Community Land Model. Two high resolution 25 km long-term simulations driven by the output from a coarser 50-km resolution simulation are performed for the period 1998–2010. One high resolution simulation uses an earlier and coarser-resolution version of plant functional type distribution and leaf area index, while the other uses a more recent, higher-quality, and finer-resolution version of the data. The results indicate that the new land cover distribution substantially alters the distribution of temperature with warming in Central Nigeria, northern Gulf of Guinea and part of the Sahel due to the replacement of C4 grass with corn; and cooling along the coastlines of the Gulf of Guinea and in Central Africa due to the replacement of C4 grass with tropical broadleaf evergreen trees. Changes in latent heat flux appear to be largely responsible for these temperature changes with a net decrease (increase) in regions of warming (cooling). The improved land cover distribution also results in a wetter monsoon season. The presence of corn tends to favor larger precipitation amounts via more intense events, while the presence of tropical broadleaf evergreen trees tends to favor the occurrence of both more intense and more frequent events. The wetter conditions appear to be sustained via (1) an enhanced soil moisture feedback; and (2) elevated moisture transport due to increased low-level convergence in regions south of 10N where the most substantial land cover differences are present. Overall the changes induced by the improved vegetation cover improve, to some extent, the performance of the high resolution regional climate model in simulating the main West African summer monsoon features.  相似文献   

14.
15.
由中国历史气候记录对季风导致唐朝灭亡说的质疑   总被引:1,自引:0,他引:1  
2007年1月4日杂志发表了Yancheva等10人的题为"Influence of the intertropical convergence zone on the East-Asian monsoon"(热带辐合带对东亚季风的影响)的论文[1],这是德国波兹坦地学研究中心气候动力与沉积学科的主管豪格(G.H.Haug)率领的科研小组的一项成果,认为是季风的变化引起的长期干旱导致了唐朝的灭亡.  相似文献   

16.
Summary ?Some features of the climate system that can be considered predictors of the onset and end of the convective season over the Amazon were identified using one-month lag correlations and field composites. The fields analyzed were sea surface temperature (SST), outgoing long-wave radiation (OLR), vertical velocity and upper tropospheric winds. Warm (cold) anomalies in the SST in the tropical North Atlantic and the Caribbean Sea tend to be associated with delayed (early) onsets. Likewise, there is a tendency towards a delayed (early) end of the convective season with cold (warm) anomalies in these ocean regions. In addition, the SST in the cold tongue region of the equatorial Pacific is negatively, though weakly correlated with the onset date. The signal of this SST is more evident in the case of the end date, which is earlier with respect to its mean date in most of El Ni?o cases. The convective activity intensity itself conditions the onset and the end of the convective season, as it is evidenced by the behavior of the OLR and the vertical velocity fields. The more (less) intense the convective activity over South America during the preceding month, the earlier the onset and the later the end of the convective season on the Amazon region. The prediction of the onset and end dates of the convective season in the Amazon region was explored using a simple multiple regression technique based on the variables that have shown precursor signals with respect to these dates. The correlation coefficient between the predicted and the observed onset date is 0.81, and in the case of the end date, it is 0.76. The skill to predict early, delayed and normal categories was high, since in more than two thirds of the cases the category was successfully predicted, and there were no predictions of categories opposed to those observed. Received July 23, 2001; revised February 22, 2002; accepted April 26, 2002  相似文献   

17.
2005 is the bicentenary of the Beaufort Scale and its wind-speed codes: the marine version in 1805 and the land version later. In the 1920s when anemometers had come into general use, the Beaufort Scale was quantified by a formula based on experiment. In the early 1970s two tornado wind-speed scales were proposed: (1) an International T-Scale based on the Beaufort Scale; and (2) Fujita's damage scale developed for North America. The International Beaufort Scale and the T-Scale share a common root in having an integral theoretical relationship with an established scientific basis, whereas Fujita's Scale introduces criteria that make its intensities non-integral with Beaufort. Forces on the T-Scale, where T stands for Tornado force, span the range 0 to 10 which is highly useful world wide. The shorter range of Fujita's Scale (0 to 5) is acceptable for American use but less convenient elsewhere. To illustrate the simplicity of the decimal T-Scale, mean hurricane wind speed of Beaufort 12 is T2 on the T-Scale but F1.121 on the F-Scale; while a tornado wind speed of T9 (= B26) becomes F4.761. However, the three wind scales can be uni-fied by either making F-Scale numbers exactly half the magnitude of T-Scale numbers [i.e. F′half = T / 2 = (B / 4) − 4] or by doubling the numbers of this revised version to give integral equivalence with the T-Scale. The result is a decimal formula F′double = T = (B / 2) − 4 named the TF-Scale where TF stands for Tornado Force. This harmonious 10-digit scale has all the criteria needed for world-wide practical effectiveness.  相似文献   

18.
准两年振荡对大气中微量气体分布的影响   总被引:11,自引:5,他引:6  
张弘  陈月娟  吴北婴 《大气科学》2000,24(1):103-110
NCAR的包含化学、辐射、动力相互作用的两维模式(SOCRATES)移植回国后进行了初步的模拟试验,用以研究某些对环境问题重要的微量气体的化学、辐射、动力传输过程。在不考虑极地平流层云和气溶胶表面非均相化学等情况下,模式积分多年,计算结果稳定,模拟的风场、温度场显示出正常的季节变化,模拟的微量气体分布与卫星实测资料对照,结果也比较一致。为了探讨热带平流层风场的准两年周期振荡(QBO)对平流层微量气体分布的影响,我们做了QBO强迫的数值试验,即在模式中加入QBO强迫,并与不考虑QBO强迫的模拟结果对比。结果表明,QBO与其相关的次级环流所引起动力输送的变化,使平流层微量气体分布发生变化。  相似文献   

19.
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 dataset. Our results show that the vertical structure of LLJs is characterized by a predominance of boundary layer jets(BLJs) concentrated at heights of 900–1200 m.The BLJs occur most frequently at 230...  相似文献   

20.
流场配置及地形对西南低涡形成的动力作用   总被引:10,自引:8,他引:10  
高守亭 《大气科学》1987,11(3):263-271
本文采用定常二层模式讨论较小地形及高、低层流场配置对西南低涡形成的动力作用。指出了西南低涡的形成是与盆地、河谷以及其上气流分层有关的一种定常态.在上、下为西风分层时期,低层的浅薄暖湿西风有利于西南低涡的形成.在上、下为东、西风分层时期,上层浅薄东风亦有利于西南低涡的形成.小型的凸起山脉对西南低涡的形成没有作用.  相似文献   

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