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91.
铁路沿线灾害性天气监测、预测、预警系统   总被引:3,自引:0,他引:3  
针对铁路三防(防风,防沙,防洪)的需要,结合大风监测系统建设的实际,对恶劣天气气候条件下,如何保障列车运行安全进行了探讨,并提出铁路沿线灾害性天气监测,预测,预警系统。  相似文献   
92.
Arecibo (18.4 N, 66.7 W) incoherent scatter (IS) observations of electron density N(h) are compared with the International Reference Ionosphere (IRI-95) during midday (10/14 h), for summer, winter and equinox, at solar maximum (1981). The N(h) profiles below the F2 peak, are normalized to the peak density NmF2 of the F region and are then compared with the IRI-95 model using both the standard B0 (old option) and the Gulyaeva-B0 thickness (new option). The thickness parameter B0 is obtained from the observed electron density profiles and compared with those obtained from the IRI-95 using both the options. Our studies indicate that during summer and equinox, in general, the values of electron densities at all the heights given by the IRI model (new option), are generally larger than those obtained from IS measurements. However, during winter, the agreement between the IRI and the observed values is reasonably good in the bottom part of the F2 layer but IRI underestimates electron density at F1 layer heights. The IRI profiles obtained with the old option gives much better results than those generated with the new option. Compared to the observations, the IRI profiles are found to be much thicker using Gulyaeva-B0 option than using standard B0.  相似文献   
93.
姚远  钱冬梅  杜德才 《气象》1996,22(2):50-52
作者应用气象资料分析烟幕的发生规律,并应用灰色理论对烟幕进行预测。  相似文献   
94.
中国及邻近地区冬到夏的季节变化   总被引:1,自引:0,他引:1  
南亚地区在冬到夏的转变过程中有显著的热力学与环境变化特征,是北半球季节变化的敏感区,对我国长期变化有十分重要的意义。根据这一特点,设计计算了南支西风指数,并将副高面积指数分南北区统计,更地地反映了季节变化特征。统计结果表明,这个指数组对梅雨与华北雨季有天气气候学意义。同时还找到了这个指数组对我国一些地区旱涝的前期指标。  相似文献   
95.
一种夏季大范围降水趋势分布的预报方法   总被引:2,自引:1,他引:2  
魏凤英  张先恭 《气象》1995,21(12):25-28
综合考虑了影响夏季降水异常的大气、海洋因子和降水变化规律,提出了一种大范围降水异常分布的统计预报方法。用1991-1994年的独立资料检验,取得了满意效果。  相似文献   
96.
文峪金矿是著名的小秦岭金矿成矿带中的重要矿床,位于河南省与陕西省交界处,本文通过系统的地球化学元素样品分析,采用数学地质统计分析方法,确定了成矿元素间的亲缘关系的组合规律,建立了该矿床成矿元素分带序列模型,指出文峪金矿深部具有良好的找矿远景。  相似文献   
97.
陕西勉略宁地区致矿地质异常场结构及找矿预测   总被引:4,自引:0,他引:4       下载免费PDF全文
陕西勉略宁“三角区”构造块体呈楔状夹持在秦岭微板块,扬子陆块和松潘甘孜褶皱带之间,目前已探讨明多种矿产,成矿作用 了自新太古代以来不同构造体抽下的多次构造,岩浆热事件和变质变形的复杂的地质作用,使致矿地质异常场结构复杂化。  相似文献   
98.
ABSTRACT

Forecasting environmental parameters in the distant future requires complex modelling and large computational resources. Due to the sensitivity and complexity of forecast models, long-term parameter forecasts (e.g. up to 2100) are uncommon and only produced by a few organisations, in heterogeneous formats and based on different assumptions of greenhouse gases emissions. However, data mining techniques can be used to coerce the data to a uniform time and spatial representation, which facilitates their use in many applications. In this paper, streams of big data coming from AquaMaps and NASA collections of 126 long-term forecasts of nine types of environmental parameters are processed through a cloud computing platform in order to (i) standardise and harmonise the data representations, (ii) produce intermediate scenarios and new informative parameters, and (iii) align all sets on a common time and spatial resolution. Time series cross-correlation applied to these aligned datasets reveals patterns of climate change and similarities between parameter trends in 10 marine areas. Our results highlight that (i) the Mediterranean Sea may have a standalone ‘response’ to climate change with respect to other areas, (ii) the Poles are most representative of global forecasted change, and (iii) the trends are generally alarming for most oceans.  相似文献   
99.
Rainfall data collected on and around the Soufriere Hills Volcano, Montserrat between 1998 and 2003 were analysed to assess the impact on primary volcanic activity, defined here as pyroclastic flows, dome collapses, and explosions. Fifteen such rainfall-triggered events were identified. If greater than 20 mm of rain fell on a particular day, the probability of a dome collapse occurring on that day increased by a factor of 6.3% to 9.2%, compared to a randomly chosen day. Similarly, the probability of observing pyroclastic flows and explosions on a day with > 20 mm of rainfall increased by factors of 2.6 and 5.4, respectively. These statistically significant links increased as the rainfall threshold was increased. Seventy percent of these rainfall-induced dome collapse episodes occurred on the same calendar day (most within a few hours) as the onset of intense rainfall, but an extra 3 occurred one or two calendar days later. The state of the volcano was important, with the rainfall–volcanic activity link being strongest during periods of unstable dome growth and weakest during periods of no dome growth or after a recent major collapse.Over 50% of the heavy rain days were associated with large-scale weather systems that can potentially be forecast up to a few days ahead. However, the remaining heavy rain days were associated with small-scale, essentially unpredictable weather systems. There was significant variability in the amount of rainfall recorded by different rain gauges, reflecting topographic variations around the volcano but also the inherent small-scale variability within an individual weather system. Hence, any monitoring/warning program is recommended to use a network, rather than just a single gauge. The seasonal cycle in rainfall was pronounced, with nearly all the heavy rain days occurring in the May–December wet season. Hence, the dome was at its most vulnerable at the beginning of the wet season after a period of uninterrupted growth. Interannual variability in rainfall was related to tropical Pacific and Atlantic sea surface temperature anomalies, and holds out the prospect of some limited skill in volcanic hazard forecasts at even longer lead times.  相似文献   
100.
运用DRASTIC方法,评价潞西盆地浅层地下水脆弱性,结合区内人类工程活动因子。对潞西盆地远期地下水脆弱性进行预测分析,成果可为区内土地规划、备用水源地的选择、垃圾填埋场的选址及实现水资源可持续利用提供合理依据。  相似文献   
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