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1.
Summary Considering the effects of causal mechanics on geophysical problems enables us to explain a number of phenomena, which cannot be explained from conventional positions. This paper shows that the introduction of the force of causality in a simple barotropic hydrodynamic model of weather forecasts results in the outcomes, which, on the one hand, can not be described from the positions of classical hydro-thermodynamics, whilst on the other hand, exist in nature.  相似文献   

2.
渤海海峡客滚船海难事故与大风事件关系分析   总被引:8,自引:0,他引:8       下载免费PDF全文
针对1999~2005年渤海海峡发生的6起客滚船海难事故,利用长岛气象站观测资料,统计得出了引发海难事故的3种风力条件。结果表明:海难事故与冷空气活动密切相关,客滚船遇险后遇到最大风力7级、极大风力大于等于9级时海上救援很困难;10月—翌年5月为在渤海海峡约三分之一的时间内有可能发生海难事故,10~11月为海难多发期。  相似文献   

3.
青藏高原雪灾变化对热带海洋海温异常响应的数值模拟   总被引:1,自引:0,他引:1  
采用青藏高原72个气象台站日积雪观测资料及 Hadley 中心海温月平均资料,在分析高原雪灾频数与海温异常关系的基础上,利用ECHAM5 模式进行雪灾变化对热带海洋关键海域 SSTA响应的敏感性试验。结果表明:(1)1978-2014年青藏高原冬半年雪灾频数总体呈减少趋势,减幅为3.4次/(10 a),尤以1998年后极为显著。雪灾空间上表现出自北向南递增的分布形式,高值区主要集中在喜马拉雅山脉北坡及嘉黎地区,而柴达木盆地及青海东部农业区为雪灾发生低值区。(2)雪灾频数变化与赤道中东太平洋、热带印度洋海温异常相关显著,敏感性试验表明,在 El Niño模态强迫下,东亚大槽偏弱,新地岛及乌拉尔山地区形成阻塞高压,偏北气流引导冷空气从西伯利亚通道南下,在高原堆积,阿拉伯海暖湿气流经伊朗高原输送至青藏高原;而在印度洋偶极子型海温模态强迫下,中纬欧亚大陆显示正异常,形成高压,同纬度西北太平洋强的负异常,使西伯利亚冷空气与西北太平洋南下湿润气流在南海转为偏南风进入高原,北印度洋异常气旋使部分南海-孟加拉湾暖湿气流进入高原,为高原降雪提供了水汽条件。  相似文献   

4.
内蒙古典型草原N2O研究刍议   总被引:15,自引:1,他引:14  
利用中国科学院内蒙古草原生态定位研究站(IMGERS)的气候、土壤、植被、土地利用方式和家畜等方面的资料,根据目前国际上N2O的研究进展,分析了内蒙古典型草原区影响N2O收支作用的可能控制因子,认为:(1)作为N2O主要来源的土壤,其理化性状,尤其是土壤温度、水分状况、土壤有机质和土壤结构等,是影响该地区N2O收支平衡的主要控制因子;(2)土地利用方式的改变对N2O的释放的影响还不十分清楚。草场农用与一定的耕作管理措施以及对天然草场的人为影响(割草、放牧等)是对N2O收支平衡影响的主要方面;(3)家畜排泄物,无论作为本地区的主要燃料,还是作为肥料,在典型草原区N2O的释放中起着不可忽视的作用。  相似文献   

5.
  1. I.
    The effect of the gamma rays from the various radioactive substances floating in the atmosphere—previously only estimated theoretically—was determined directly by measuring the total ionization with and without a 1,2 cm. iron plate on top of the ionization chamber which was shielded on the bottom and on all sides by 10 cm. iron. The absorption of the soft component of cosmic radiation in 1,2 cm. iron was taken into account. It was found that the gamma radiation from the radioactive substances in the atmosphere (“air radiation”) amounts, on the average to 0,15I (ion pairs per cm.3·sec) near the ground. It varies considerably from day to day. These variations can exaggerate or mask actual fluctuations which may occur in the soft component of cosmic rays.  相似文献   

6.
刘永强 《气象》1988,14(11):13-16
在计算我国7站(其中东部季风区5个站)10年逐日大气湿度参量的基础上,对大气湿润状况的一些基本统计性质,包括均方差、标准误差、偏度及不同等压面上湿度变化的相关性等,进行了分析。结果表明,这些统计量的地理分布、季节变化及不同高度之间的差异等均与季风气候的特征有着密切的联系。  相似文献   

7.
兰州市心血管病与气象条件分析   总被引:2,自引:0,他引:2  
利用兰州市区三大医院 1996~ 2 0 0 0年病历资料和兰州观测站 1996~ 2 0 0 0年的压、温、湿资料以及天气图资料 ,对兰州市区心血管病与气象条件的关系进行分析总结 ,并用逐步回归法建立了春季心血管病等级预报方程  相似文献   

8.
Based on reconstructions of precipitation events from the rain and snowfall archives of the Qing Dynasty (1736–1911),the drought/flood index data mainly derived from Chinese local gazettes from 1736–2000, and the observational data gathered since 1951,the spatial patterns of monsoon rainbands are analyzed at different time scales.Findings indicate that monsoon rainfall in northern China and the middle-lower reaches of the Yangtze River have significant inter-annual(e.g.,5–7-yr and 2–4-yr)as well as inter-de...  相似文献   

9.
Since Global Positioning System dropwindsonde wind measurements are taken in neither a conventional Eulerian framework nor a perfect Lagrangian framework, proper post-processing is necessary to derive conventional Eulerian wind statistics from dropwindsonde measurements. In this study, the equations governing the dropwindsonde motions were first linearized and then analytically solved to explore the effects of the wind-finding equations introduced by Hock and Franklin (Bull Amer Meteor Soc 80:407–420, 1999) when retrieving horizontal winds from dropwindsonde measurements. It is found that the wind-finding equations are essential for calculating turbulence statistics from dropwindsonde measurements. To confirm, numerical simulations of dropwindsonde motions in a pseudo-stochastic wind field were further conducted based on the full nonlinear dropwindsonde motion-governing equations. Based on the simulation results, the present paper showed the effects of the wind-finding equations and the companion paper discussed the impacts of various post-processing/composition schemes on both the mean and turbulent wind statistics composited from pseudo-dropwindsonde measurements.  相似文献   

10.
Considered is a possibility of using the previously developed method for estimating the evapotranspiration from the river basin based on the observations at the network of water- and soil-evaporation stations and on the data on the land use dynamics for the Northern Dvina and Western Dvina river catchments. It is demonstrated that the method enables to obtain rather realistic and reliable estimates both of evapotranspiration over the basin and of the contribution of different landscapes to its value. The value of evapotranspiration and its interannual variability depend not only on the trends in the fluctuations of evaporation from the water surface and the land surface, but also on the changes in landscape characteristics. The present paper is a continuation of the papers dealing with the study of the basins of the Volga and Don rivers started under V.S. Golubev’s leadership and participation.  相似文献   

11.
21世纪珠江流域水文过程对气候变化的响应   总被引:4,自引:0,他引:4  
应用HBV-D水文模型和多个气候模式预估了不同温室气体排放情景下珠江主干流西江的径流过程,分析了21世纪水资源量和洪水频率的变化。结果表明:2050年后年降水量和年径流量较基准期(1961—1990年)明显增加;流域平均的月降水量和径流量在5—10月间均呈增加趋势,12月至次年2月呈减少趋势;年最大1 d和7 d洪量逐渐增加,重现期逐渐缩短。2030年前枯水期径流增加有望缓解枯水期用水压力,而2050年之后丰水期径流量以及洪水强度、发生频率的增加将给珠江流域防汛抗洪带来更大压力,在制订气候变化对流域水资源影响适应性对策时应考虑这两方面的影响。  相似文献   

12.
The results of heavy metal measurements in monthly precipitation samples are analyzed at biological station Dal’nie Zelentsy to define the role of the atmospheric precipitation in the marine environment pollution in the Barents Sea coastal region. Peculiarities of the atmospheric processes and the genesis of air masses bringing the precipitation and the extent of their effect on the precipitation pollution with heavy metals are considered based on the data obtained in 2001–2002. Of the air masses brining the precipitation to the Kola Peninsula coast the air masses of a marine origin have significant advantage. It is shown that weight average heavy metal (except copper) concentrations in the precipitation from the marine air masses on the Kola coast are higher than in the precipitation from the continental air masses. The emissions from local metallurgic enterprises influence the extent of the precipitation pollution with copper.  相似文献   

13.
新旧南京国家基准气候站观测数据差异   总被引:4,自引:1,他引:3  
南京国家基准气候站2008年1月1日完成迁站。虽然新旧站址直线距离只有7 km,但两地地形、环境都存在较大差异,找出资料序列的差异性对气象资料的连续性、代表性、均一化分析具有重要意义。我们利用2006—2007年的观测资料,分析两站点资料的差异,研究外部环境对资料差异产生的可能影响,依据气候学原理、气候统计方法及气候资料审核规范,结合南京的气候特点,对一些重要天气条件(高温、低温、大风、暴雨等)下两个观测点各气象要素进行分析,研究各气象要素对环境的敏感性。通过两个观测站点资料的对比分析,为今后南京站气象资料的应用提供科学依据。  相似文献   

14.
Achieving food and nutrition security for all in a changing and globalized world remains a critical challenge of utmost importance. The development of solutions benefits from insights derived from modelling and simulating the complex interactions of the agri-food system, which range from global to household scales and transcend disciplinary boundaries. A wide range of models based on various methodologies (from food trade equilibrium to agent-based) seek to integrate direct and indirect drivers of change in land use, environment and socio-economic conditions at different scales. However, modelling such interaction poses fundamental challenges, especially for representing non-linear dynamics and adaptive behaviours.We identify key pieces of the fragmented landscape of food security modelling, and organize achievements and gaps into different contextual domains of food security (production, trade, and consumption) at different spatial scales. Building on in-depth reflection on three core issues of food security – volatility, technology, and transformation – we identify methodological challenges and promising strategies for advancement.We emphasize particular requirements related to the multifaceted and multiscale nature of food security. They include the explicit representation of transient dynamics to allow for path dependency and irreversible consequences, and of household heterogeneity to incorporate inequality issues. To illustrate ways forward we provide good practice examples using meta-modelling techniques, non-equilibrium approaches and behavioural-based modelling endeavours. We argue that further integration of different model types is required to better account for both multi-level agency and cross-scale feedbacks within the food system.  相似文献   

15.
青藏高原地形对孟加拉湾热带气旋影响的对比研究   总被引:4,自引:1,他引:4  
本文用我们的实验室模拟、个例诊断分析的结果与综合分析方法得到的热带气旋的典型结构相对比,进一步探讨了高原地形对孟加拉湾热带气旋的影响(消亡及降水等)机制问题。  相似文献   

16.
In much of sub-Saharan Africa, considerable research exists on the impacts of climate change on social-ecological systems. Recent adaptation studies emphasize sectoral vulnerability and largely physical adaptation strategies that mirror anti-desertification plans. The adaptive role of subsistence farmers, the vulnerable ‘target’ population, is largely overlooked. This article aims to fill this gap by putting the views from the vulnerable in the center of the analysis. Drawing from participatory risk ranking and scoring among smallholders in central Senegal, data on multiple hazards indicate that farmers’ adaptive capacity to climate change is undermined by poor health, rural unemployment, and inadequate village infrastructure. Results from conceptual mapping reveal incomplete understanding of causes and consequences of climate change. Yet, shared knowledge and lessons learned from previous climatic stresses provide vital entry points for social learning and enhanced adaptive capacity to both wetter and drier periods now and in the future.  相似文献   

17.
Results of measuring methane emissions from the Lammin-Suo oligotrophic bog massif are considered. It is shown that emission intensity depends on the methane transport from the active layer of the peat bed. The highest emission intensity is observed in the sedge-sphagnum microlandscape and over swampy hollows of the hummock-ridge complex. It is found that the methane flux intensity approaches zero when the wetland level drops by 30–35 cm from the bog surface. Spatial methane emission variability is estimated within dominating bog landscapes. The methane emission reaches its maximum values (207%) in microlandscapes with oriented microrelief (hummock-ridge complex); in the central bog (sphagnum-suffrutescent-cottongrass landscape afforested with pine), it reaches its lowest level (76%). A model of methane emissions from bogs is developed. The model has been verified from the observational data. The comparison of model calculations with experimental data is indicative of their good agreement, which makes it possible to use the model in different calculations and assessments of the influence of natural factors on the methane emission intensity.  相似文献   

18.
用机载粒子测量系统(FSSP-100、2D-C、2D-P)和其他云物理测量仪器,对四川春季一次冷锋前层状云降水进行了探测。探测结果是:春季层状云降雨并不都是由高层卷云、高积云自然引晶激发而成的,它可以是由层状云(As op),特别是层状云中对流云群产生的针状、鞘状、棱柱状冰雪晶的聚并体和凇附形成的霰粒自身激发降水的。这些降水胚元长大成雨滴,其质量增长主要在负温层;初始直径D0=600微米的霰粒胚元,在负温层中增长的质量占总的增长质量的70%以上。  相似文献   

19.
以青藏高原东北缘山地地区不同海拔高度地理单元村落的农户为调查对象,进行气候变化、气象灾害的感知及适应策略等调查,采用感知强度公式及专家打分法分析农户气候变化感知以及所采用的适应策略,结果显示:1961—2013年湟水中游气候变化整体趋于暖干化,有84%的农户认为气候变暖,并对其生活造成了严重的影响;在不同海拔高度上的地理单元,农户对气象灾害的感知有明显差异,川水地区农户对沙尘的感知最强,浅山地区农户对虫害的感知最强,而脑山地区农户对连阴雨的感知最强;不同海拔高度的农户对适应策略的选择不同,川水地区农户主要采取“生产性+生活性+保障性”组合适应策略;浅山地区农户主要采取“生产性+生活性”组合适应策略;而脑山地区的农户则主要采取单一的“生产性”适应策略来应对气候变化所带来的影响。  相似文献   

20.
利用多通道地球同步卫星资料,采用多通道阈值、基于晴空合成底图和云图时间序列的阈值和相似检测、有限区域动态阈值检测等方法,运用分步决策思路,对(60°S~60°N、45~165°E)区域内卫星云图分中高云和低云进行云地分离综合处理。经人工判断与自动云地分离结果对比分析表明,准确率达到90%以上。分析表明,考虑云和地(海)表在不同通道的亮温差异和随时间演变特点,建立并运用多种云地分离方法,有利于云地分离信息量的增加;提出的考虑云系分布时变特性的相似检测法,以及从有云和无云两个角度优先选择高可信度方法逐步检测,有利于云地分离准确率的提高。  相似文献   

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