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1.
泾河流域气候变化及其与ENSO的关系 总被引：1，自引：0，他引：1
ENSO(厄尔尼诺-南方涛动)常引起大气环流的改变并导致气候异常,探讨区域气候变化与ENSO的关系有助于理解区域水文等各方面的变化.通过Mann-Kendall、相关性检验和小波分析等方法.研究了1960-2005年泾河流域气候变化及其与ENSO的关系.结果表明,1960-2005年,泾河流域气候趋向暖干,且这种趋势在90年代以来愈加显著.气候变化与ENSO有显著的关系.降水对ENSO的响应程度强于温度;降水可能受南方涛动的影响比较大,而温度可能受海表温度的影响较多;ENSO暖事件对泾河流域气候变化的影响可能大于冷事件. 相似文献
2.
ENSO事件与山西气候的关系 总被引：2，自引：0，他引：2
通过搜集和整理1955-2008年大同、河曲、原平、太原、阳泉、介休、离石、长治、临汾、运城等地的气象资料,分析了山西的降水量、气温与ENSO事件的关系,研究了ENSO事件对山西气候的影响。结果表明,1955-2008年ENSO事件呈现出起伏波动的特点,1980年以后波动趋势更为剧烈;大致可分为两个阶段:1955-1980年为第1阶段,ENSO冷事件的频次略高于暖事件,但强度更大;1981-2008年为第2阶段,ENSO暖事件的频次和强度均高于冷事件。ENSO事件对山西降水量的影响表现十分明显,ENSO暖事件当年降水量明显偏低,次年降水量明显增加或达到最高趋势明显。ENSO冷事件年全省降水量均明显增加。ENSO事件对山西气温的影响也十分显著,ENSO暖事件年大多表现为气温偏高或升温,ENSO冷事件年一般表现为气温偏低或降温。 相似文献
3.
海面变化研究是具重要理论和实践意义的地学研究领域。全球性气候变化、海面升降和环境变迁的预测等研究,引起国际学术界和各国政府部门高度重视,成为国际地圈－生物圈计划 相似文献
4.
地质灾害的非线性数据处理与建模技术 总被引：3，自引：1，他引：2
本文简略地介绍了几种地质灾害数据处理与建模的非线性方法,主要包括GMDH自组织建模技术、神经网络方法。GMDH是一种高阶非线性回归建模方法,它是以简单的二元二次回归方程为基础,通过"代复一代"的"生产"过程,客观、自动地求得实际资料的非线性模型。而神经网络则是用工程技术手段模拟生物神经网络的结构特征和功能特征的一类人工系统。与常规统计方法相比,神经网络最突出的优点为它是通过对网络的学习和训练,来掌握变量之间的非线性关系。因此,其处理复杂问题的能力更强大。实例检验效果表明,这些非线性数据处理与建模技术考虑了地质灾害问题的非线性特性,其比基于常规统计理论的数据处理方法的精度要高得多。 相似文献
5.
《中国地理与资源文摘》2007,(1)
P461200701082740a来中国旱灾对ENSO事件的区域差异响应研究=Asyn-chronous response of droughts to ENSO in China/卢爱刚,葛剑平…∥冰川冻土.—2006,28(4).—535~542利用中国各地区1949-1990年间旱灾的受灾面积比和成灾面积比,分别与ENSO指数进行相关分析.结果发现:ENSO指数与各地的旱灾事件有着一定的反相关关系,表明ENSO的发生对我国大部分地区有着显著的影响,特别是对华北、东北、华南、内蒙古和新疆等地区的相关性具有很好的显著水平.通过对比各个分区对ENSO事件的响应程度,分析了其空间差异性.图6表2参40(洪明)BiX4320… 相似文献
6.
西方经济地理学新进展及其启示 总被引：23，自引：2，他引：21
从地理学家的制度、文化、关系和尺度转向及主流经济学家的"新经济地理学"诸方面,评述了西方经济地理学近年的研究进展,指出这两支脉络交互学习有利于经济地理学的发展.为发展中国特色经济地理学,应科学借鉴西方经验,注重在研究中分析和提炼理论问题,不断引进相关学科理论,合理使用模型和计量方法,加强微观视角和政治经济研究;在此基础上,应重视中国经济地理学的发展背景,科学看待已有研究特点,发掘特殊的思维方法.中国国情下的独特问题的研究,比如经济发展空间格局的理论研究,区域文化与经济关系研究,区域人口、资源、环境与经济协调发展研究等,对于推出受国际学术界关注的成果,具有十分重要意义. 相似文献
7.
基于文献计量的新世纪中国自然地理学国际影响力分析 总被引：1，自引：1，他引：0
以美国科学情报机构、科学引文索引数据库(SCI-E)为数据源,通过文献计量方法从总发文趋势、文章引用率、一流学术机构、核心作者分布、发文热门期刊以及关键词等方面,对中国自然地理学在国际学术界的发展情况、学术地位以及面临的问题与挑战进行分析。结果显示：新世纪中国自然地理学在国际领域发展迅速,在自然地理学领域能够发挥特长并贡献力量,在学术界占有一席之地。文献成果方面,至2016年底,中国在自然地理学权威机构的发文量占比达18.96%,位居世界第二。高质量文章占有率增长十余个百分点,文献累计被引量从0次跃升至2万余次,研究成果逐渐受到国际学术界认可。研究力量上,研究机构数量(排名第八)与学者数量(第四)均位居世界前列且发展趋势良好,中国自然地理学在其发展过程中,于多方面表现出了质和量的突破;从国际形势看来,中国自然地理学者通过多年不断努力,能够紧跟研究潮流,把握研究热点方向,但在理论创新及全球环境问题的研究等方面,仍有一定的提升空间。 相似文献
8.
反映水文学最新发展的学术专著《现代水文学》 ,近日由黄河水利出版社正式出版发行。《现代水文学》是以现代新技术新理论应用为支撑 ,系统阐述现代水文学的理论、方法及应用 ,为水问题研究 ,提供现代水文学的研究基础。全书系统阐述了水循环的概念、原理及研究进展 ,水文不确定性问题、非线性问题和尺度问题的研究意义与基本方法 ,水文系统识别的概念、原理和方法 ,“3Ｓ”技术及在水文学中的应用 ,水资源可再生性研究和可持续水资源管理量化研究 ;还介绍了代表水文模型发展方向的分布式水文模型、水文 -生态耦合系统模型等。该书作者左其… 相似文献
9.
河道纵剖面分形—非线性形态特征 总被引：28，自引：1，他引：28
混沌－分形研究是非线性地貌发育理论尤其是非线性流水地貌学研究的前沿问题，是当代地 貌学深层次研究的一个重要界面，在国内外刚刚起步。本文在概述国内外研究进展基础上，以黄河下游及长江中下游为例，运用粗视化方法，对不同河段、不同河型的河床深泓纵剖面进行了分维量计和检验。 相似文献
10.
马歇尔产业区理论的复兴及其理论意义 总被引：7，自引：0，他引：7
20世纪70年代末期以来,在日趋激烈的全球经济竞争背景下,区域发展问题逐步成为国际学术界研究的一个热点领域。其中,在经济地理学和区域科学领域,产业区研究作为当代经济学的"新异端"和"新区域主义"的代表而受到了学者们的极大关注。文章论述了马歇尔"产业区"理论的特点和复兴过程,讨论了马歇尔式"产业区"的分类,深入阐述了"产业区"研究在当代社会科学研究中的理论意义。 相似文献
11.
Although studies have demonstrated significant associations between ENSO events and dengue fever, few have explored regional impacts on dengue fever of separate events. This study explores the impacts of two ENSO events on regional patterns of dengue/ dengue haemorrhagic fever (DHF) incidence in Indonesia. Data consist of monthly cases of dengue/DHF from 1992 to 2001 for each of Indonesia's 27 provinces, and monthly figures for rainfall, rainfall anomalies, temperature, relative humidity and the Southern Oscillation Index (SOI). We conducted Pearson correlation analyses for each independent variable against dengue/DHF incidence, using a direct month‐by‐month correlation and applying a lag of between one and six months to each variable with respect to dengue/DHF incidence. Based on the SOI value, we identified two ENSO events between 1992 and 2001. To explore each event, we created two dummy variables and in regression analyses for eight provinces. The variance of between 12.9 per cent and 24.5 per cent in provincial dengue/DHF incidence is explained by two or three climate variables in each of the provinces (p < 0.01 to 0.1). During the 1997/98 event, the explained variance increased by between 7 per cent and 15 per cent in provinces whose climate regimes were most affected by this event. This study demonstrates that indicators of ENSO such as the SOI may assist in the forecast of potential dengue/DHF incidence and distribution in Indonesia. 相似文献
12.
Characteristics of change of the SST in the tropical western Pa-cific and the tropical Indian Ocean and its response to the change of the Antarctic ice area 
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下载免费PDF全文 In this paper, by using ocean surface temperature data(COADS), the study is made of the characteristics of the monthly and annual changes of the SST in the tropical western Pacific and Indian Oceans, which have important influences on the climate change of the whole globe and the relation between ENSO(El Nio Southern Oscillation) and the Antarctic ice area is also discussed. The result indicates that in the tropical western Pacific and the Indian Oceans the change of Sea Surface Temperture(SST) is conspicuous both monthly and annaully, and shows different change tendency between them. This result may be due to different relation in the vibration period of SST between the two Oceans. The better corresponding relationship is obvious in the annual change of SST in the tropical Indian Ocean with the occurrence El Nio and La Nia. The change of the SST in the tropical western Pacific and the tropical Indian Oceans has a close relation to the Antarctic ice area, especially to the ice areas in the eastern south Pole and Ross Sea, and its notable correlative relationship appears in 16 months when the SST of the tropical western Pacific and the Indian Oceans lag back the Antarctic ice area. 相似文献
13.
The influence of monsoon climatic characteristics makes the tropics of China different from those of other parts of the world. Therefore, the location of the northern boundary of China's tropical zone has been one of the most controversial issues in the study of comprehensive physical regionalisation in China. This paper introduces developments in the study of the northern boundary of China's tropical zone, in which different scholars delimit the boundary with great differences based on different regionalisation objectives, indexes, and methods. The main divergence of opinion is found in different understandings of zonal vegetation, agricultural vegetation type, cropping systems, tropical soil type and tropical characteristics. In this study, we applied the Geo Detector model, which measures the spatial stratified heterogeneity, to validate the northern boundaries of the tropical zone delimited by six principal scholars. The results show that the mean q-statistic value of the higher latitude boundary delimited by Ren Mei'e is the largest(q=0.37), suggesting that, of the rival views, it best reflects the regional differences between China's tropical and subtropical zones, but it is not necessarily suitable for guiding the development of tropical agriculture. The mean values of the q-statistics of Zheng Du's line and Yu Xianfang's line around the Leizhou Peninsula at a lower latitude were smaller, at 0.10 and 0.08 respectively, indicating that the regional differences were smaller than those of Ren Mei'e's boundary. Against the background of global climate change, the climate itself is changing in fluctuation. It is, thus, worth our further research whether the northern boundary of the tropical zone should not be a fixed line but rather should fluctuate within a certain scope to reflect these changes. 相似文献
14.
Connie A. Woodhouse 《自然地理学》2013,34(5):417-435
The influence of climate associated with El Niño/Southern Oscillation (ENSO) events on tree growth in the central Colorado Front Range is investigated through the analysis of two high altitude tree-ring chronologies. Dendrochronological techniques are used to determine if ENSO-related climatic effects are detectable in tree-ring width patterns in the central Colorado Front Range. The form of the tree-growth response is identified and the variability of the influence of these events on tree growth over time is investigated. Results indicate that tree growth in this area does respond to ENSO events, but the response varies with species and type of event. El Niño-influenced climate tends to result in larger tree rings the year of or year following the event, while La Niña-influenced climate tends to result in smaller rings the year after the event, reflecting spring moisture conditions. Trees have a more consistent response to La Niña events, but El Niño events seem to have a greater effect on extremes in growth. The relationship between the Southern Oscillation Index (SOI) and tree growth has varied over time, probably because of the fact that ENSO events, characterized by the SOI, vary in magnitude and amplitude. [Key words: ENSO, dendrochronology, Colorado Front Range.] 相似文献
15.
Rengui Jiang Ruijuan Cao Xi Xi Lu Jiancang Xie Yong Zhao Fawen Li 《Singapore journal of tropical geography》2020,41(3):384-412
Extreme precipitation indices (EPIs) were defined to quantify the precipitation extremes in Singapore, a typical tropical country situated near the equator. The paper investigated the spatial and temporal variability of precipitation extremes based on seventeen EPIs using non-parametric Mann-Kendall test and Sen’s slope, and further explored the linear and nonlinear relationships between precipitation extremes and four large-scale global climate oscillations using correlation and wavelet analysis, during the period of 1980–2018 in Singapore. The results indicated that the trends of precipitation extremes varied for different EPIs, regions and stations. Increasing trends dominated thirteen out of seventeen EPIs. The trends of EPIs were scattered and irregularly distributed. The cross-correlation analysis between different EPIs demonstrated that annual total precipitation on wet days (PRCPTOT) was strongly correlated with other EPIs. The result of composite analysis indicated that El Niño Southern Oscillation (ENSO) exerted stronger impacts on southwest monsoon season (SMS) precipitation than PRCPTOT and northeast monsoon season (NMS) precipitation. The SMS precipitation composite suggested that ENSO created more influence on dry spells than wet spells. The linear and nonlinear relationships revealed that all climate oscillations were negatively correlated with precipitation. The wavelet coherence and phase differences were consistent with the results of correlation analysis, indicating possible prediction of precipitation extremes using climate oscillations as potential predictors. 相似文献
16.
Wildfires have long been an important environmental concern in Florida. Recent wildfires along the urban-rural interface of large cities in Florida have pointed to the need for an increased understanding of the physical and biological mechanisms that govern wildfire occurrence. Increased awareness of the relationships between global climate changes occurring in the tropics and their teleconnections outside the tropics dictate a reevaluation of the role of phenomena such as El Niño-Southern Oscillation on the risk of wildfire. One simple way of illustrating the relationship between ENSO and wildfire occurrence is the use of an Analysis of Variance (ANOVA) on wildfire data that has been categorized according to ENSO status (El Niño, La Niña, and neutral years). This research shows that a statistically significant relationship exists between ENSO conditions and annual wildfire occurrence in Florida when ENSO conditions are treated as a potential precursor to wildfire conditions. In particular, a statistically significant relationship exists between both acreage burned and average fire size, when the data are separated into El Niño and La Niña categories according to the previous year's ENSO status. This supports the idea that the climate from previous years has a measurable effect upon fire statistics in the years following the climate measurements, and that it may be possible to create a regional fire prediction model that incorporates ENSO information. [Key words: wildfire, natural hazards, ANOVA, Florida, ENSO.] 相似文献
17.
淮河流域降水过程时空特征及其对ENSO影响的响应研究 总被引：2，自引：1，他引：1
基于淮河流域35个站点1961~2008年日降水资料,从成因角度研究不同厄尔尼诺-南方涛动事件（ENSO）事件对流域降水过程时空演变特征的影响。研究表明：① 流域降水过程出现沂沭泗河水系变干、淮河水系降水量缓慢增大的特征。② CPW年,年最长连续降水日数、年最长连续降水量的距平变化幅度大且为负值;EPC年,年最长连续无降水日数较常年明显增多;EPW年,连续降水日数变长、连续降水量减少。③ ENSO对流域强降水影响较大,在CPW和EPW年淮河水系暴雨、大雨日数较常年多,而沂沭泗河水系暴雨、大雨日数比常年少;EPC年与此相反。④ ENSO对连续4 d以上降水影响显著,其中EPC年影响最大。 相似文献
18.
A one-dimensional global climate model is constructed from both the basic energy balance equation for the earth-atmosphere system and the planetary boundary layer equations of motion. The theoretically based model accurately simulates many features of the present climate system and appears useful in evaluating various climatic change mechanisms. The simplicity of this process-response model increases its educational and research applicability for climatologists in geography. 相似文献
19.
The influence of monsoon climatic characteristics makes the tropics of China different from those of other parts of the world. Therefore, the location of the northern boundary of China’s tropical zone has been one of the most controversial issues in the study of comprehensive physical regionalisation in China. This paper introduces developments in the study of the northern boundary of China’s tropical zone, in which different scholars delimit the boundary with great differences based on different regionalisation objectives, indexes, and methods. The main divergence of opinion is found in different understandings of zonal vegetation, agricultural vegetation type, cropping systems, tropical soil type and tropical characteristics. In this study, we applied the GeoDetector model, which measures the spatial stratified heterogeneity, to validate the northern boundaries of the tropical zone delimited by six principal scholars. The results show that the mean q-statistic value of the higher latitude boundary delimited by Ren Mei’e is the largest (q=0.37), suggesting that, of the rival views, it best reflects the regional differences between China’s tropical and subtropical zones, but it is not necessarily suitable for guiding the development of tropical agriculture. The mean values of the q-statistics of Zheng Du’s line and Yu Xianfang’s line around the Leizhou Peninsula at a lower latitude were smaller, at 0.10 and 0.08 respectively, indicating that the regional differences were smaller than those of Ren Mei’e’s boundary. Against the background of global climate change, the climate itself is changing in fluctuation. It is, thus, worth our further research whether the northern boundary of the tropical zone should not be a fixed line but rather should fluctuate within a certain scope to reflect these changes. 相似文献
20.
基于地理探测器的中国亚热带北界探讨 总被引：1，自引：0，他引：1
暖温带与亚热带的分界线,是自然区划中一条重要的自然界线,它的划分问题曾引起诸多学科学者的争论。由于早期综合自然区划研究多以定性、专家集成方法为主,同时区划目的、使用指标等多有不同,导致不同学者所划分的自然区多存在一定的差异。本文基于空间分异性思想,使用地理探测器定量探测气候指标对中国亚热带北界的影响,选择其中q值较大的指标如日均温≥0℃天数、最冷月1月均温、年降水和湿润指数等作为主导因子并参考植被、土壤数据探讨亚热带北界界线的位置。结果表明：① 地理探测器法可以快速、准确地筛选自然区划的主要气候指标,并确定分界线的准确位置,提高了自然区划研究的技术水平和区划界线的客观性。② 使用地理探测器划分的新界线在研究区西部位于秦岭南坡1000~1600 m的位置,与以往界线相比略偏南;在研究区东部河南东部、安徽北部比以往界线略偏北。在保持自然要素完整性的同时,新界线具有更大的q值,表明新界线可以很好的反映暖温带与北亚热带2个区划带之间的差异,划分结果具有合理性。 相似文献