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一种插值相似方法作温度预测的应用研究 总被引：1，自引：1，他引：1
将插值方法运用到短期气象预测中，其基本原理是按照相似原理将产生相似结果来作预报。对云南昆明等四站温度进行了九年定性和定量预报检验，结果表明：这种方法具有良好的预报能力，可以作要素预报应用。 相似文献
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湖北省乡镇温度预报方法初探 总被引：11，自引：2，他引：9
为了提高精细站点温度预报水平,本文在中尺度模式精细化温度预报的基础上,结合MOS分县客观预报结果,采用带海拔高度的距离权重温度插值方法,经过灰色预测模型修正温度预报误差,对湖北省717个四要素自动观测站的72小时内日高低温度进行了精细化预报,并且利用乡镇自动站温度观测进行了检验。结果显示：对于没有历史观测资料的站点,采用此预报方法,预报效果明显高于模式预报结果,基本接近客观预报方法,可以进行业务应用。对湖北的四要素自动观测站温度检验的结果还表明：鄂西北的预报误差最大,江汉平原的预报效果最好;从分月预报情况来看,高低温度都是夏季和初秋预报效果最好,低温预报冬春季预报效果最差,湖北各个区域趋势基本都一致,而高温的预报却没有一致的趋势。 相似文献
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基于欧洲中期天气预报中心(ECMWF)第五代全球再分析资料(ERA5)构建模式气候,应用ECMWF集合预报,采用“集合预报标准化异常预报法”,针对最高和最低气温构建中国地区集合平均异常温度预报和异常温度概率预报产品,并与极端预报指数(extreme forecast index,EFI)开展检验和对比分析预报性能,并基于“异常温度影响矩阵”,构建了异常温度影响程度预报指数,通过异常温度事件个例探讨相关产品的预报应用。结果表明:基于ECMWF的ERA5和集合预报构建的集合平均异常温度预报产品对我国夏季和冬季异常温度事件均有比较好的预报效果,预报性能好于或接近EFI,可作为业务上对异常温度事件预报的支撑产品。异常温度概率预报产品可以体现集合成员中的预报异常温度事件的信息,在中期预报时效对发现早期异常温度事件信号有优势,并可反映对异常天气预报的不确定性信息。异常温度影响程度预报指数结合了异常天气概率预报信息和异常程度预报信息,可对异常温度时间给出客观定量的预报结果,对一次异常低温事件的个例预报证明该指数有比较好的预报效果,对异常温度事件的预报和早期科学预警有一定指示意义和业务应用前景。 相似文献
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应用数值天气分析预报产品，选择与宜宾各县温度、降水有较好相关的预报因子，利用模式输出统计(MOS)法，建立温度、降水的分县、客观预报方程，从而达到气温、降水预报的定点、定量的目标。 相似文献
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通过对北京数值预报新模式Ｔ１０６的温度客观预报释用结果分析及对新（Ｔ１０６）、旧（Ｔ６３）模式的日极端温度预报结果对比，证明了Ｔ１０６模式更优于Ｔ６３模式，且各预报时效更加稳定；同时，说明动态ＭＯＳ日极端温度预报模块能够克服模式变化的影响，使客观预报质量达到较高水平 相似文献
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面向全国2000多个台站，应用数值预报产品释用MOS技术制作温度、降水、相对湿度、风、云量及能见度等要素预报，并实现了预报业务运行。通过建立MOS预报系统，表明预报因子和预报对象的处理，建方程前的参数选择以及预报因子的选取都会影响要素预报的质量，需要做大量的细致工作。预报检验结果显示，降水预报尚未达到可用程度，温度和相对湿度的短期预报在大多数情况下是可用的或是可参考的，但还有待进一步改进。降水预报尚需在预报因子和充分运用多种探测信息方面着手加以改进。 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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准两年振荡对大气中微量气体分布的影响 总被引：6，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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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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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
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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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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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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