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利用地面气象观测站探测环境调查结果,分析观测场四周障碍物分布变动情况,对于选取能见度目标物有指导意义。在此基础上,运用Google earth、GPS、数码照相、visio2003软件等技术手段配合制作出新的能见度目标物分布图,有助于提高台站能见度观测业务质量。 相似文献
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1980年1月1日开始执行的新版《地面气象观测规范》(简称新规范),具有广泛的群众基础,反映了我国地面测报工作的经验和特点。 经过这一段对新规范的学习,我有以下几点体会。 1.总结了经验。广大气象观测工作者,经过长期的实践,积累了丰富的观测经验。新规范将现阶段测报工作中行之有效的观测经验有选择地予以列入。比如,在云的观测上,新规范归纳了夜间云的观测的三条经验,对山区台站云的观测叙述也比较详细。在夜间能见度观测方面,分别指出有目标灯和无目标灯须掌握的几条原则。特别是白天能见度的观测,根据所选目标物的颜色和其细微部分“清晰可辨”、“隐约可辨”、“很难分辨”三种情况下能见度估计方法。只要 相似文献
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为了适应沙尘天气预报服务的需要，新版《地面气象观测规范》新增了地面状态、最小能见度以及草面(雪面)温度观测等项目。根据新规定，最小能见度观测是我省所有台站均需观测的项目，但并未明确一般站的记录方法，因此一般站如何按照新版《地面气象观测规范》的要求作好观测记录，就成为广大测报人员在学习新版《地面气象观测规范》时的一个重点。 相似文献
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为了适应沙尘天气预报服务的需要,新版《地面气象观测规范》新增了地面状态、最小能见度以及草面(雪面)温度观测等项目。根据新规定,最小能见度观测是我省所有台站均需观测的项目,但并未明确一般站的记录方法,因此一般站如何按照新版《地面气象观测规范》的要求作好观测记录,就成为广大测报人员在学习新版《地面气象观测规范》时的一个重点。
相似文献5.
在气象工作中观测能见度的根本目的是为了鉴定大气透明度,即气象能见度剔除了光学能见度的其他制约条件,只受大气透明度一个因子的影响。现行《地面气象观测规范》(以下简称《规范》)及其他气象书籍中关于气象能见度的定义意义基本相同。这些定义的核心是:能见度是视力正常的人在当时天气条件下能够看到或辩认目标物的最大距离。尽管《规范》和某 相似文献
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地面气象观测规范,是气象台站从事地面气象观测工作的依据和准则。它主要包括观测组织工作、观测场、观测方法、气象观测仪器和记录整理等内容。我国地面气象观测规范到目前为止,共计有十个版本(见附表)。大致分四种类型:最初沿用英国《测候指南》;1946年以后主要参照美国地面气 相似文献
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气象观测是气象工作的基础 ,而地面气象观测是气象观测工作的重要组成部分 ,也是每个气象台站的基本任务之一。为获取具有代表性、准确性、比较性的气象资料 ,为气象预报提供准确数据 ,加强测报管理工作是非常必要的。1 严格规范化管理地面气象观测规范、技术汇编、报告电码以及上级业务部门下发的文件等 ,都是做好地面观测工作的根本依据 ,是衡量测报工作的尺子。然而怎样实施上述规定 ,严格规范化管理是最为关键的。1 1 严格执行目标化管理办法葫芦岛地区从 1 992年开始实施目标化管理办法 ,制定了一套适应本地区的测报工作管理目标 ,… 相似文献
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地面自动气象观测设备运行状态信息检测技术 总被引：1，自引：0，他引：1
地面自动气象观测设备运行状态检测机制不足一直是困扰我国地面气象观测运行保障工作的一大难题。本研究从运行监控实际业务需求角度出发,在梳理现有业务运行地面自动气象观测设备结构基础上,结合部分研究成果,从数据采集模块、气压观测模块、温湿度观测模块、风观测模块、地温观测模块、雨量观测模块、供电系统模块、软件模块、能见度观测模块和称重降水观测模块共10个方面逐一细化了每一主要部件的状态检测点,并对其进行了分类和编码,同时参考现行业务运行设备长Z数据报文,制定了地面自动气象观测设备运行状态报文规范,最终研制了地面自动气象观测设备运行状态信息检测技术。通过统一规范、标准,研究结果可解决目前我国地面自动气象观测设备监控信息设计规范缺失的问题,可缓解当前厂家多、型号杂、设备不统一的不利局面,有利于推进地面自动气象观测设备运行监控技术规范化建设工作。 相似文献
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1980年地面气象观测规范变更对能见度资料连续性影响研究 总被引：2，自引：0，他引：2
为探讨1980年地面气象观测规范变更对能见度资料连续性,采用累积百分率法、Ridit分析法、"非常好"能见度分析法等工具,对1951—2006年南宁、桂林城市大气能见度变化进行了分析。分析显示:南宁、桂林能见度高值在1980年相对1979年迅速下降,并导致平均Ridit值,"非常好"能见度天数迅速降低,其原因是1980年采用新《地面气象观测规范》的结果,采用能见度高值、Ridit值、"非常好"能见度对比分析1980年前后的能见度变化是不可信的;南宁、桂林能见度中、低值受1980年采用新的《地面气象观测规范》的影响较小,保持了很好的连续性,资料跨越1980年是连续可靠的,可以用来进行对比分析1980年前后的能见度变化。 相似文献
10.
能见度目标物是台站地面观测工作不可缺少的能见度观测参照物。能见度目标物分布图的准确程度 ,直接关系到能见度这一目测项目的精确度。但我省大多数台站现用的目标物图 ,均系多年前按当时地貌物貌实测绘制的 ,一直沿用至今 ,很少做过补充订正或变更修改 ,已远不能保证现时测报业务质量。随着社会进步和经济发展 ,各地城市建设日新月异 ,高层建筑拔地而起 ,楼台亭阁鳞次栉比 ,庞大厂房管网纵横交错 ,使当初的地形物貌面目全非。由于城市统一规划和房屋拆迁 ,使原有能见度目标物遭到破坏 ,数目逐渐减少 ;因高低错落的建筑群体相互遮掩 ,使观… 相似文献
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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
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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
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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
张德二 《气候变化研究进展》2008,4(2):126-130
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
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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
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Comparing the theoretical versions of the Beaufort scale, the T-Scale and the Fujita scale 总被引：1，自引：0，他引：1
G. Terence Meaden S. Kochev L. Kolendowicz A. Kosa-Kiss Izolda Marcinoniene Michalis Sioutas Heino Tooming John Tyrrell 《Atmospheric Research》2007,83(2-4):446-449
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
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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
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.
Chunguang CUI Wen ZHOU Hao YANG Xiaokang WANG Yi DENG Xiaofang WANG Guirong XU Jingyu WANG 《大气科学进展》2023,40(4):711-724
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
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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
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