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前言 气候资料是天气状况的真实记录,是天气予报和气象科学研究的重要依据,也是其他科学的重要参考资料。实现气候资料服务自动化,做到快速、及时、准确,是摆在资料服务工作面前急待解决的问题。我们研制《气候资料检索服务系统》的目的就是使地区级气候资料服务实现自动化,提高工作效率,减少重复劳动,同时也为气候资料阶段整编打下基础。 相似文献
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高原涡、西南涡研究的新进展及有关科学问题 总被引:2,自引:0,他引:2
李国平 《沙漠与绿洲气象(新疆气象)》2013,7(3):1-6
简要回顾了青藏高原天气研究的历史,重点综述了进入21世纪后的近十年来青藏高原天气研究领域中有关高原低涡、西南低涡的若干重要进展,总结了相关研究取得的主要成果,在此基础上归纳出了当前高原天气研究存在的主要问题和需要加强的研究方向,以期有助于更好地梳理青藏高原天气影响的科学问题,推动青藏高原大气科学试验及研究的有序开展。 相似文献
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我们新安江水电厂的气象予报工作相当于县站予报,是专门为水电专业服务的。我想结合我们开展予报的实践来谈以下三个问题。 一、统计予报是今后发展方向之一 在统计予报没有引进县站予报之前,在一次予报讨论中,使用同一张曲线图,由于各人看问题的角度 相似文献
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为了改变短期予报缺乏工具的状况,我们试验了一种“短期天气编码相似予报法,在今年六月份的试验予报中,除其中有三天由于历史上没有出现过相同的编码,实际用了27天,24小时予报共54段,报准的有46段,准确率达85.2%,予报效果尚可。现将制作方法介绍如下: 我们选择了对逐日晴雨预报指示性比较好,用得比较多的三个要素,(均为14时的) 1.T—e和△P24:将数值编成七个码: 相似文献
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本文在上海台风研究所无地形的业务数值予报模式中引入地形,用实际天气过程进行了地形动力效应的予报试验。结果表明,引入地形后的模式,其予报能力有明显改善,尤其是对500hPa高空槽以及地面冷高压活动的予报,模式地形表现出重要影响。由此说明,即使在有限区域短期数值予报模式中,引入地形也是十分必要的。 相似文献
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近几年,县站长期天气予报应用数理统计的方法逐步增多,使用的予报因子也越来越多,据全地区各站的不完全统计,使用因子最多达一千多个,最少也有四百个以上。如何正确地应用这些予报因子制作予报方法和工具,促使县站予报质量和服务效果不断得到提高,这是 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
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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