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1.
对内蒙古春季沙尘暴的时空分布特征以及沙尘暴与大风、气温、降水、冷空气活动的关系进行了统计分析。得出沙尘暴空间分布不均匀,在自西向东减少的同时,有4个中心;绝大多数测站自70年代中后期以来明显减少,只是近年来略有增加;大风与沙尘暴统计关系密切,但个例分析则不然,少数测站沙尘暴比大风更容易发生;降水抑制沙尘暴发生;近期增温有利于沙尘暴的发生;冷空气与沙尘暴的关系各地情况不一。  相似文献   

2.
宋桂英  孙永刚  王德民  韩经纬 《气象》2007,33(S1):76-84
利用内蒙古地区沙尘暴实测资料和北半球NCEP再分析资料(1955—2000年),分析了内蒙古地区沙尘暴的气候变化特征;厄尔尼诺、拉尼娜事件发生后,北半球大气环流异常和温、湿分布异常及其对沙尘暴发生的可能影响关系与机制。分析表明:内蒙古中西部地区1960、1970年代强沙尘暴过程频繁,1980、1990年代沙尘暴明显减少。拉尼娜事件发生后,冰島冷高压与欧亚大陆暖低压的相互作用是沙尘暴频发的重要因素。拉尼娜事件对华北沙尘暴频发有重要气象作用。春季北半球干旱地区处于易发生沙尘暴的天气系统背景下。改善生态环境,减小沙化程度是治理沙尘暴的有效途径。  相似文献   

3.
智海  沈桐立  张喜林  方晓红 《气象》2006,32(S1):3-10
以实况资料作初始场,利用中尺度自适应模式对西北地区2000年4月12日强沙尘暴的天气形势和风场进行了数值模拟,对此分析得出西部地区沙尘暴的形成、发展机制和中小尺度系统对于沙尘暴发生发展的触发和指示作用。由于模式的输出结果是每3小时一次,比常规资料更能表现出沙尘暴的内在机制及时间和空间尺度较短的系统。结果表明:在沙尘暴发生前河西走廊西部就出现偏西大风,高空急流对沙尘暴发生区有很好的指示作用,强沙尘暴发生在200hPa高空急流入口区右倒,上升运动区内;高空急流发生变异时,导致对流层中下部锋区加强和大气层结不稳定,为中尺度系统的发生、发展和沙尘暴的产生提供了适宜的大尺度环流背景;西北地区干暖舌的形成和维持对沙尘暴的发生区有很好的指示作用,当冷锋过境时,干暖区是沙尘暴发生的最有利的环境。  相似文献   

4.
利用TOMS资料遥感沙尘暴的研究   总被引:6,自引:5,他引:6  
研究了利用TOMS资料定量遥感沙尘暴的方法,并利用该方法遥感了1998年4月15日发生在中蒙边境地区的一次沙尘暴过程,得到了沙尘暴的发生、发展、强度以及影响范围等特征.结果表明,该方法基本上可以排除云的影响,能够定量遥感沙尘暴的动态发展过程,是一个较好的沙尘暴遥感方法.  相似文献   

5.
根据内蒙古阿拉善地区1985-2005年21年的沙尘暴气象资料,分析了沙尘暴发生、发展变化规律,其结果表明:阿拉善地区确实是一个沙尘暴的高发区;按年平均计算的沙尘暴发生次数具有明显的波动性,有高发期和低发期;阿拉善沙尘暴的成因主要与自然因素有关。  相似文献   

6.
河西走廊盛夏一次强沙尘暴天气综合分析   总被引:10,自引:1,他引:10  
王锡稳  刘治国  黄玉霞  张铁军  程鹏 《气象》2006,32(7):102-109
利用常规气象观测资料和NCEP/NCAR月平均再分析资料,对2003年7月20日甘肃河西走廊一次历史上少见的区域性夏季沙尘暴天气进行了分析。研究发现:高空小槽、切变线、热低压是引发夏季沙尘暴的主要天气系统。夏季沙尘暴发生过程中,各测站出现了气压跃升、风速猛增、气温下降、湿度增加等现象,但变化幅度小于春季。夏季沙尘暴云图特征表现为中小尺度云团,TBB≤-35℃的云团在一定程度上能够反映沙尘暴天气的变化。诊断分析表明,沙尘暴爆发前散度场呈低层辐合高层辐散状态,沙尘暴发生在最大垂直速度出现以后,同时水平螺旋度对夏季沙尘暴预报有较好的指示意义,螺旋度正值越大,沙尘暴越强。  相似文献   

7.
贺哲  王蕊  梁钰 《河南气象》2005,(3):11-12
对河南省沙尘暴时空分布特征及影响因子分析发现:河南省沙尘暴在东部平原地区发生频率高于西部山区,在驻马店以北,年沙尘暴日数为1的等值线基本上与地势海拔100m地形等高线相吻合;沙尘暴的多发地区,沙尘暴日数年际变化在多数年份较为剧烈;河南省沙尘暴沙源并非全部来自省外,省内下垫面沙尘对沙尘暴的发生起了一定的促进作用;沙尘暴的发生与降水量关系极不明确,但在部分年份与月最长无降水日数和日照时数之间存在着一定的对应关系。  相似文献   

8.
喀什地区近43年沙尘暴、扬沙天气   总被引:1,自引:0,他引:1  
根据喀什地区11个气象观测站的地面气象记录月报表,分析了1961~2003年沙尘暴和扬沙天气现象资料,给出了近43年喀什地区沙尘暴和扬沙天气的时空分布特征及其历史演变特征。结果表明:喀什地区沙尘暴和扬沙发生频率较高,大部分县市是沙尘暴的多发区和易发区、扬沙的高频区和多发区;沙尘暴和扬沙平原地区主要发生春季中后期及夏初,山区主要发生在春季;沙尘暴历史演变总体以减少为主,扬沙平原地区逐渐减少,相反高山站塔什库尔干呈增加态势,沙尘暴和扬沙的减少均是在波动中减少的。  相似文献   

9.
甘肃沙尘暴短期、短时业务化预报方法研究   总被引:5,自引:0,他引:5       下载免费PDF全文
利用1955~2002年甘肃省80个站的观测资料,对发生在甘肃境内的64个强或特强沙尘暴个例逐个进行了天气气候分析,总结了甘肃沙尘暴天气气候特点,沙尘暴爆发的天气类型,移动路径。得出沙尘暴短期和临近预报的着眼点,建立了甘肃沙尘暴短期预报概念模型。通过用计算机语言和模块化设计方案,成功设计了中国西北地区沙尘暴监测预警人机交互预报平台,实现了沙尘暴监测预警预报业务化。  相似文献   

10.
文章对2005年5月8~10日呼和浩特地区一次强沙尘暴过程进行了天气学分析及物理量诊断,结果表明:本次过程系统发展的主要强迫来自对流层高层,高空锋区的动量下传导致强地面风产生是沙尘暴发生的动力条件;沙尘暴发生前层结稳定度的降低及沙尘暴发生期间中性混合层的维持,为沙尘暴发生提供了适宜的层结条件。同时,大气整层的正涡度和对流层中低层的上升运动,也是沙尘暴形成和增强的重要原因。  相似文献   

11.
国家级现代农业气象业务技术进展   总被引:8,自引:4,他引:4       下载免费PDF全文
农业气象业务技术是开展农业气象服务的基础和前提,因此,农业气象业务技术的研发一直是国家级农业气象业务服务的核心工作。近年来,国家级农业气象业务技术已逐步迈向精细化、定量化,涵盖了农业气象监测评价、作物产量预报、农业气象灾害监测评估与影响预报、农用天气预报、农林病虫害发生发展气象等级预报等诸多领域。随着农业气象业务技术的发展,支撑农业气象服务的客观产品更加丰富和多样化,既有站点产品,又有格点产品,涵盖了日、周、月、季、年等不同时间尺度。以农业气象指标、数理统计模型、作物生长模拟、卫星遥感、地理信息系统、大数据等技术为核心的国家级农业气象业务平台(CAgMSS)已成为全国农业气象业务系统的重要品牌。面向现代农业发展对气象服务日益增长的需求,精细化、精准化的农业气象灾害监测与风险评估技术、作物长势评估与产量预报综合集成技术、农业应对气候变化技术以及农业气象大数据挖掘与人工智能技术将是未来国家级农业气象业务技术发展的重点。  相似文献   

12.
电线积冰物理过程与数值模拟研究进展   总被引:1,自引:0,他引:1  
杨军  谢真珍 《气象》2011,37(9):1158-1165
电线积冰对人们的日常生活、电力系统、通信系统等造成了巨大的影响,人们越来越关注电线积冰的形成条件及物理过程,包括气象条件、气流动力学、液滴运动轨迹以及热力学过程。通过外场观测、室内实验和数值模拟研究的不断开展,揭示出电线积冰质量增长过程决定于云降水粒子谱分布、碰撞效率、黏性率、冻结率、碰撞速度和角度等微物理参数,这些参数又受控于降水率、云雾含水量、温度、湿度、风向、风速等宏观气象条件。通过数值模式已可进行电线积冰量和积冰持续时间的定量研究和预测,进而在开发垂冰模式和形态模式等方面也取得了新的进展。在总结过去60多年来电线积冰物理机制和数值模拟研究主要成果的基础上,对开展进一步的深入研究进行了展望。  相似文献   

13.
As the impacts from anthropogenic climate change are increasing globally, people are experiencing dramatic shifts in weather, temperature, wildlife and vegetation patterns, and water and food quality and availability. These changes impact human health and well-being, and resultantly, climate change has been identified as the biggest global health threat of the 21st Century. Recently, research is beginning to indicate that changes in climate, and the subsequent disruption to the social, economic, and environmental determinants of health, may cause increased incidences and prevalence of mental health issues, emotional responses, and large-scale sociopsychological changes. Through a multi-year, community-led, exploratory case study conducted in Rigolet, Nunatsiavut, Labrador, Canada, this research qualitatively explores the impacts of climate change on mental health and well-being in an Inuit context. Drawing from 67 in-depth interviews conducted between January 2010 and October 2010 with community members and local and regional health professionals, participants reported that changes in weather, snow and ice stability and extent, and wildlife and vegetation patterns attributed to climate change were negatively impacting mental health and well-being due to disruptions in land-based activities and a loss of place-based solace and cultural identity. Participants reported that changes in climate and environment increased family stress, enhanced the possibility of increased drug and alcohol usage, amplified previous traumas and mental health stressors, and were implicated in increased potential for suicide ideation. While a preliminary case study, these exploratory findings indicate that climate change is becoming an additional mental health stressor for resource-dependent communities and provide a baseline for further research.  相似文献   

14.
利用四川省1981—2013年雾、轻雾、吹雪、雪暴、烟幕、霾、沙尘暴、扬沙和浮尘9种视程障碍天气现象资料,对其发生日数、发生概率和分布特征进行统计。结果表明:(1)各天气现象发生日数排序为:轻雾>雾>浮尘>霾>烟幕>扬沙>沙尘暴>吹雪>雪暴。(2)轻雾和雾年发生日数为分别为176d/a和29d/a,日发生概率分别为48%和8%,远高出其他天气现象。(3)季节变化方面,雾和轻雾主要出现在秋季和冬季;霾、吹雪和雪暴集中出现在冬季;浮尘发生春季;扬沙多发生在冬季和春季;而沙尘暴、烟幕主要发生在春季和秋季。(4)变化趋势上轻雾基本保持平稳;烟幕呈增加趋势;而雾、霾、沙尘暴、扬沙和浮尘呈下降趋势。(5)大气层结稳定、水汽充足、风速较小、人口集中和排放量较大,易于盆地雾、轻雾、霾和烟幕的形成;不合理利用水和土地资源,北方地区沙尘天气随冷空气南下,是沙尘天气发生的重要原因;而吹雪和雪暴均发生在冬季降雪量大且风速较大的川西高原。  相似文献   

15.
Vulnerability of Aboriginal health systems in Canada to climate change   总被引:1,自引:0,他引:1  
Climate change has been identified as potentially the biggest health threat of the 21st century. Canada in general has a well developed public health system and low burden of health which will moderate vulnerability. However, there is significant heterogeneity in health outcomes, and health inequality is particularly pronounced among Aboriginal Canadians. Intervention is needed to prevent, prepare for, and manage climate change effects on Aboriginal health but is constrained by a limited understanding of vulnerability and its determinants. Despite limited research on climate change and Aboriginal health, however, there is a well established literature on Aboriginal health outcomes, determinants, and trends in Canada; characteristics that will determine vulnerability to climate change. In this paper we systematically review this literature, using a vulnerability framework to identify the broad level factors constraining adaptive capacity and increasing sensitivity to climate change. Determinants identified include: poverty, technological capacity constraints, socio-political values and inequality, institutional capacity challenges, and information deficit. The magnitude and nature of these determinants will be distributed unevenly within and between Aboriginal populations necessitating place-based and regional level studies to examine how these broad factors will affect vulnerability at lower levels. The study also supports the need for collaboration across all sectors and levels of government, open and meaningful dialogue between policy makers, scientists, health professionals, and Aboriginal communities, and capacity building at a local level, to plan for climate change. Ultimately, however, efforts to reduce the vulnerability of Aboriginal Canadians to climate change and intervene to prevent, reduce, and manage climate-sensitive health outcomes, will fail unless the broader determinants of socio-economic and health inequality are addressed.  相似文献   

16.
Dust sediments collected from 1995 to 1998 in Beijing, Dunhuang, Inner Mongolia, Kashi, the Kunlun Mountains, Lanzhou, Ningxia, the Taklimakan Desert, and Xi‘an, China, were characterized in terms of their physical, chemical, and mineralogical properties. Most aerosols and dust analysed ranged in texture from silty clay to clay loam. Their median particle diameters (Mds) generally ranged between 5 to 63μm,coinciding with those of loess from central China and the finest sand from northwestern China. The dust sediments were characterized by a predominance of SiO2 and Al2O3, followed by K2O. Their SiO2/Al2O3and K2O/SiO2 molar ratios ranged from 5.17 to 8.43 and from 0.009 to 0.0368, respectively. The mass concentration spectrum during a dust storm showed a single peak, rather than the triple peak generally observed under clear sky conditions. The dominant minerals were chlorite, illite, calcite, and dolomite.These physical, chemical, and mineralogical properties were consistent with those of aeolian soils and loess in western and central China. The results suggest that aerosols and fine-gained fractions of dust sediments collected in northern China are mainly composed of soil material transported from the arid and semiarid regions of China and Mongolia by prevailing winds. The rate of deposition and properties of dust falling on eastern China were strongly influenced by meteorological conditions, season, latitude, longitude, and altitude of the sampling sites.  相似文献   

17.
近50年黄河上游径流量与气候变化特征研究   总被引:1,自引:0,他引:1  
根据1956-2010年唐乃亥水文站逐月径流量资料和1961-2009年黄河上游兴海、泽库、玛沁、达日、久治、玛多6个代表站的降水量、气温资料,分析了唐乃亥站径流量与黄河上游地区降水和气温的气候变化特征及其关系.结果表明:春、夏、秋、冬季的径流量分别占年径流量的14.9%、2.9%、34.7%、7.5%;唐乃亥站年和四...  相似文献   

18.
This conceptual review article provides a critical appraisal of Sustainable Consumption and Production research, which is currently framed by two generic positions. First, the ‘reformist’ position, which focuses on firms pursuing green eco-innovations and consumers buying eco-efficient products, represents the political and academic orthodoxy. Second, the ‘revolutionary’ position, which is a radical critique of the mainstream, advocates the abolishment of capitalism, materialism, and consumerism, and promotes values such as frugality, sufficiency, and localism. We find this dichotomous debate problematic, because it is intellectually stifling and politically conservative (in its outcomes). To move beyond this dichotomy, we propose a third position, ‘reconfiguration’, which focuses on transitions in socio-technical systems and daily life practices and accommodates new conceptual frameworks. For each of the three positions, we discuss: (1) the scale and type of change, (2) views on consumption and production in exemplary approaches, (3) underlying theoretical, epistemological and normative orientations, (4) policy implications, and (5) critical appraisal. The conclusion compares the three positions, provides arguments for the fruitfulness of the reconfiguration-position and offers four critical reflections about future Sustainable Consumption and Production research agendas.  相似文献   

19.
利用1964-2015年气象观测资料对河北廊坊冰雹天气的时空分布特征进行分析,并利用MICAPS资料、北京探空资料及多普勒雷达资料研究了廊坊冰雹日的天气形势、物理量特性及雷达回波特征。结果表明:廊坊冰雹日数整体呈下降趋势,20世纪80年代末至90年代初降雹达到高峰期。冰雹天气主要发生在1519时,多持续1~5 min。廊坊冰雹有明显的地域特征,西北部较多。降雹日500 hPa环流形势有4类,并对应3种地面形势。对预报冰雹天气有指导意义的物理量参数阈值为:冰雹开始前对流层中下层存在逆温层或等温层;对流参数SI指数或LI指数<0,中低层假相当位温随高度减小;0 ℃层高度多为3050~4702 gpm,-20 ℃层高度多为5996~8332 gpm,850 hPa与500 hPa温差为27~32 ℃,低层有大的垂直风切变,近地面925 hPa垂直风切变为5.5~15.0 m·s-1·km-1。此外,廊坊冰雹云回波有块状单体和飑线两种结构,回波中心强度普遍大于60 dBz,垂直结构上均有悬垂回波,速度场为逆风区或旋转速度>12 m·s-1的弱切变,VIL普遍大于35 kg·m-2,ET普遍大于11 km。  相似文献   

20.
国家级天气预报检验分析系统建设与应用   总被引:1,自引:1,他引:0       下载免费PDF全文
为了适应精细化预报和业务管理的发展需求,国家气象中心建设开发了基于Web的国家级天气预报检验分析系统。系统分为预报检验、检验文件解析处理、检验数据查询分析与检验平台管理4个功能模块,关键技术包括标准化的数据管理、开放式的算法模块管理与调度和检验数据的可视化分析。系统建立了规范高效的检验业务数据流程,兼容处理预报分析制作系统(MICAPS)数据、GRIB2数据、城镇报数据、自动气象站数据等其他专业气象数据,涵盖了国家级省级智能网格预报、全国城镇天气预报、定量降水预报、大城市空气质量预报等数十项检验业务产品,给出了空间分布、柱状图及数据表格等展现形式。系统为全国各级预报员、模式开发人员和管理人员提供预报检验反馈信息,为各省以及国家级预报业务考核提供了信息支撑;同时系统提供逐旬、月、年度的智能网格预报以及城镇天气预报的检验结果对比,有力支撑了智能网格预报产品业务研发和业务试验。  相似文献   

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