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四川省短期灾重天气预报中的几个问题 总被引：1，自引：1，他引：0
就我省短期重大灾害性天气预报业务中的一些技术问题进行了分析。重点讨论了重大灾害性天气的启动机制、能量锋生消、中尺度系统分析和不同系统相互作用等问题,并给出了定性和定量诊断方法。这有助于预报员在业务预报中进一步把握好有关信息,促进短期重大灾害性天气预报质量的提高。 相似文献
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青海省气象局自1999年开始推行预报业务体制改革以来，经过几年的发展，目前已逐步建立了以数值天气预报产品为基础，以人机交互处理系统为平台，综合应用多种技术方法的天气预报业务流程，短期预报和气候预测业务现代化建设成效显著，短期气候趋势预测、一般性降水预报及灾害性天气预报准确率逐年稳步提高，有力地促进了青海省天气预报服务水平和能力的提升。 相似文献
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引言 七五期间,江西省初步建成了STYS系统,完成了以中速通信、实时资料库、图形图像库和局地网络等为基础的省级气象实时业务服务系统,开发了长、中、短期天气预报自动化或半自动化业务系统。以气象卫星资料、天气雷达监测资料和灾害性天气联防为基础的短时天气预报业务得到加强,提高了灾害性天气的监测预报和服务能力。初步改变了单一依靠天气图作预报的状况,我省的天气预报正向以计算机处理为主要手段,以数值预报产品应用为基础,各种信息和方 相似文献
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北方灾害性天气预报科研协作第二届年会于1979年9月在青海西宁召开.会议总结交流了自1976年第一届年会以来我国北方灾害性天气预报的科研成就.一、寒潮预报(一)短期预报近年来,北方寒潮短期预报的研究工作,主要是通过各种物理量的计算,探索寒潮爆发的物理机制, 相似文献
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经过全区预报人员五年的努力,我区的灾害性天气预报,无论是短期还是短时,都已经摆脱了低水平徘徊的局面,正在稳定地提高.1 近5年灾害性天气预报质量情况1.1 全区年度质量由表1可以看出,近几年来全区短期、短时灾害天气预报质量都已走出低谷,呈稳定上升趋势,与1986—1990年平均质量相比,短期预报有进步;短时因评分办法变更影响,提高的质量在表中反映不出来. 相似文献
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《重要天气电码》是继续贯彻“全国灾害性天气会议”,加强灾害性天气预报、情报工作,尤其是加强短时天气预报的一项重大措施,也是气象业务改革的一次重大措施,也是气象业务改革的一次重要尝试,是关系到气象业务工作走新路子的大事。因此,学好、用好《重要天气电码》是气象测报人员义不容辞的责任。这里就我初学《重要天气电码》谈点粗浅的看法,以起到抛砖引玉之作用。 相似文献
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介绍了重要灾害性天气预报评分系统 ,该系统不仅可以对短期和中期单站的一般性降水和暴雨 (雪 )、高温、大风、沙尘暴、冰雹、霜冻、寒潮等重要灾害性天气预报进行质量评定 ,而且可以进行区域预报评分。 相似文献
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自进入90年代以来,我区气象现代化建设取得了长足进展.1992年建立了地级计算机远程工作站,1994年5月份又建立了地级计算机局域网,并逐步延伸到县级.计算机远程工作站和局域网投入业务使用,不但大大提高了天气预报特别是重大灾害性天气预报的准确率,减轻了低效的重复性劳动,同时也扩大了气象部门的知名度,增强了自我发展能力.经过近几年的业务实践证明,系统在业务运行中是正常的,可以满足当前业务工作的需要. 相似文献
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在短期天气预报中,以往都是把灾害性天气和日常天气捆在一起,以固定发布时间和固定预报时段对公众发布预报的.这种定时预报,对日常天气来说是理所当然的,因为它是预报某日的天气;而对灾害性天气来说却不尽然,因为某种灾害性天气的致害程度在于它的强度和持久程度.由于灾害性天 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