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1.
珠穆朗玛峰北坡冰川表面不同季节气象特征分析   总被引:1,自引:0,他引:1  
在极端高海拔地区获取定点的气象观测资料对于研究山地冰川与气候变化的关系极为重要。2005年5月1日-7月22日(春末夏初)和2007年10月2日-2008年1月19日(秋冬)在珠峰地区海拔6560m的东绒布冰川积累区进行了包括气温、湿度、风向风速和气压在内的气象要素观测。对观测资料的分析表明,气温和湿度与附近较低海拔定日气象站的变化趋势基本一致,证明了在极端环境下获得的气象观测资料的合理性。春末夏初月平均气温从5月的-11.3℃上升到7月的-3.4℃,秋冬季月平均气温则从10月的-11.3℃下降到次年1月的-19.0℃。在春末夏初受印度季风影响,湿度呈持续增加趋势,月平均湿度混合比从5月的1.4g/kg增加到7月的5.4g/kg;而在西风环流控制下的秋冬季湿度呈缓慢降低,月平均湿度混合比从10月的1.4g/kg降低到次年1月的0.5g/kg。春末夏初主要以阴天为主,秋冬季则是晴天占据主导地位。西风环流控制时东绒布冰川盛行西北风,风速较大,极端最大风速可达35m/s。而受印度季风影响时东绒布冰川以南风为主,风速相对较小。  相似文献   

2.
Ground-based measurements are essential for understanding alpine glacier dynamics,especially in remote regions where in-situ measurements are extremely limited.Prom 1 May to 22 July 2005(the spring-summer period),and from 2 October 2007 to 20 January 2008(the autumn-winter period),surface radiation as well as meteorological variables were measured over the accumulation zone on the East Rongbuk Glacier of Mt. Qomolangma/Everest at an elevation of 6560 m a.s.l.by using an automatic weather station(AWS).The...  相似文献   

3.
NOAA和USGS是美国主要从事气象和水文业务与科研的两大联邦政府部门,随着NASA将科学任务重点从太空科学转向地球科学,除了继续开展卫星观测技术和遥感数据的开发和应用之外还关注水文气象领域的研究.作为国际山地中心主持的“兴都-库什-喜马拉雅地区卫星遥感降水估算”项目的内容之一,本人于2011年5~6月参加了由国际山地中心(ICIMOD)组织的赴美交叉学习活动,先后参观和考察了NOAA和USGS的主要部门和其他一些相关单位,与NASA科学家进行了广泛的交流.本文简要介绍了这些单位开展的水文气象业务和科研工作、卫星遥感应用情况以及学习访问期间的感想与体会,对提高我们目前的相关业务和科研工作以及体制机制的创新方面有一定的借鉴意义.  相似文献   

4.
杨军  孔大力  陈果  胡永云 《大气科学》2023,47(1):167-173
近年来,国家自然科学基金委员会地球科学部地球科学五处(大气科学学科)调整了基金申请代码,优化了学科布局。其中,一个重要改变是新增了二级申请代码D0508行星大气。本文就这一申请代码下的3个研究方向和24个关键词的设置进行解读,说明其设置的具体缘由和相关联系。通过本文的介绍,基金申请人可以更好地了解这些研究方向与关键词的设置逻辑,为基金申请过程中更为准确地选择研究方向与关键词提供借鉴。新增该申请代码的主要目的是促进我国行星大气研究,壮大我国行星大气科学研究队伍,不断推进我国大气科学的发展。  相似文献   

5.
珠峰地区大气边界层结构的一次观测研究   总被引:5,自引:15,他引:5  
利用2005年8月31日~9月5日中国科学院珠穆朗玛峰综合观测研究站的LAP3000风廓线仪的观测资料,分析了该地区气温日变化和大气边界层风廓线结构。结果表明,该地区1500 m以下大气边界层主要受高原山地地形及珠峰地区冰川环境的影响,冰川风可能是引起观测期间下午强风天气的主要原因;1500 m以上高空受西风气流影响程度增大,但东南风仍占有一定比例。  相似文献   

6.
Summary Meteorological observations in the eastern part of the Himalayas (Tibetan side of Shisha Pangma and of Mt. Everest, 1984) are compared with observations of the Karakoram (north side of K2, 1986). Both sites are characterized by different weather patterns within the global circulation. This is evident also in the expedition data obtained during September and October 1984 and 1986. Temperature gradients and the development of the daily wind system of the two areas are shown.With 6 Figures  相似文献   

7.
Changes in ocean heat content(OHC), salinity, and stratification provide critical indicators for changes in Earth’s energy and water cycles. These cycles have been profoundly altered due to the emission of greenhouse gasses and other anthropogenic substances by human activities, driving pervasive changes in Earth’s climate system. In 2022, the world’s oceans, as given by OHC, were again the hottest in the historical record and exceeded the previous 2021 record maximum.According to IAP/CAS data, ...  相似文献   

8.
Measurements of fog and rain water chemistry at the summit of Mt. Fuji, the highest peak in Japan, as well as at Tarobo, the ESE slope of Mt. Fuji in September 2002. The pH of fog and rain water sampled at Mt. Fuji varied over a range of 4.0–6.8. Acidic fogs (pH < 5.0) were observed at the summit when the air mass came from the industrial regions on the Asian continent. The ratio of [SO42−]/[NO3] in the fog water was lower at Tarobo than at the summit. High concentrations of Na+ and Cl were determined in the rain water sampled at the summit, possibly because of the long-range transport of sea-salt particles raised by a typhoon through the middle troposphere. The vertical transport of sea-salt particles would influence the cloud microphysical properties in the middle troposphere. Significant loss of Mg2+ was seen in the rain water at the summit. The concentrations of peroxides in the fog and rain water were relatively large (10–105 μM). The potential capacity for SO2 oxidation seems to be strong from summer to early autumn at Mt. Fuji. The fog water peroxide concentrations displayed diurnal variability. The peroxide concentrations in the nighttime were significantly higher than those in the daytime.  相似文献   

9.
关于提高天气预报准确率的几个问题   总被引:10,自引:0,他引:10  
矫梅燕 《气象》2007,33(11):3-8
提高天气预报准确率是气象业务的一项基础性、系统性的工作。作者从天气预报的业务技术体系着眼,借鉴发达国家的发展经验,分析了提高天气预报准确率的若干问题,提出了发展精细化的预报技术体系,将数值预报模式、天气学预报方法、动力诊断和统计释用及基于卫星和雷达等现代探测技术的短时临近预警技术相结合的预报技术路线;提出了有利于精细化预报的业务体系,即发展以定量降水预报、台风预报和灾害性天气短时临近预警为重点的专业化预报业务体系;指出专家型预报队伍的建设是提高预报业务水平的关键环节。  相似文献   

10.
姜大膀  燕青  闻新宇 《大气科学》2023,47(1):119-124
为了深入推进新时代自然科学基金改革,2019年大气科学学科率先对2008年版的申请代码进行了优化调整,形成了“分支学科”“支撑技术”和“发展领域”三大有序板块。特别是,2020年新版申请代码设置了“古气候模拟与动力学(D0503)”,实现了大气科学从“分钟、小时直至地史”时间尺度的全覆盖。本文从D0503代码的增设背景、学科内涵、研究方向、关键词、未来发展等方面进行解读和展望,并对近三年该代码下“面青地”项目的申请和资助情况进行了分析。希望本文能够帮助科研人员充分理解D0503研究方向与关键词的内涵和逻辑关系,及时把握该代码的发展趋势,服务古气候研究方向的基金项目申请和评审。  相似文献   

11.
The aim of this work is to define over the period 1979–2002 the main synoptic weather regimes relevant for understanding the daily variability of rainfall during the summer monsoon season over Senegal. “Interannual” synoptic weather regimes are defined by removing the influence of the mean 1979–2002 seasonal cycle. This is different from Part I where the seasonal evolution of each year was removed, then removing also the contribution of interannual variability. As in Part I, the self-organizing maps approach, a clustering methodology based on non-linear artificial neural network, is combined with a hierarchical ascendant classification to compute these regimes. Nine weather regimes are identified using the mean sea level pressure and 850?hPa wind field as variables. The composite circulation patterns of all these nine weather regimes are very consistent with the associated anomaly patterns of precipitable water, mid-troposphere vertical velocity and rainfall. They are also consistent with the distribution of rainfall extremes. These regimes have been then gathered into different groups. A first group of four regimes is included in an inner circuit and is characterized by a modulation of the semi-permanent trough located along the western coast of West Africa and an opposite modulation on the east. This circuit is important because it associates the two wettest and highly persistent weather regimes over Senegal with the driest and the most persistent one. One derivation of this circuit is highlighted, including the two driest regimes and the most persistent one, what can provide important dry sequences occurrence. An exit of this circuit is characterised by a filling of the Saharan heat low. An entry into the main circuit includes a southward location of the Saharan heat low followed by its deepening. The last weather regime is isolated from the other ones and it has no significant impact on Senegal. It is present in June and September, and missing in July and August, meaning that this is a weather regime more specific of the intermediate seasons than the summer. It is included in a large-scale pattern covering the northern latitudes of Europe. The correspondence between these “interannual” synoptic weather regimes and the “pure” synoptic regimes defined in Part I has been established. By selecting a high statistical significance level for these correspondences, each of five out of nine “interannual” weather regimes has a close correspondence with one “pure” synoptic weather regime, one out of them have links with two “pure” regimes, and the last three regimes have no significant correspondence in terms of “pure” regimes. However when considering more moderate links, two out of these three regimes show a connection with a “pure” regime, and the last one remains isolated. The ensemble of the weather regimes occurrences can explain a significant part of interannual variability of summer rainfall amount over Senegal, especially linked to the driest and the wettest weather regimes occurrences. It is also shown that Senegal rainfall state is very sensitive to a small displacement or deformation of the weather regime patterns.  相似文献   

12.
Mt. Qomolangma (also known as Mt. Everest), the world’s highest mountain, is situated over the world’s highest plateau, the Tibetan Plateau. Because of its height and because of its distance from industrialized areas, the environmental state of the Mt. Qomolangma region can normally be considered “undisturbed”. It is interesting to investigate how this “undisturbed” state has been changing with time and whether it has been influenced by large environmentally disruptive events such as the Kuwait oil fires of 1990 and 1991 (Small, 1991). In order to do this, riv-er water samples were collected from the Rongpu River at Rongpu Temple Station in the summers of 1992 and 1993, as was done in 1975, and aerosol samples were collected in the summer of 1992 at the same station as was done in 1980. River water samples were analyzed using atomic absorption spectroscopy (AAS) at the Chinese Academy of Sciences. Aerosol samples were analyzed using proton-induced x-ray emission (PIXE) at the University of Fudan in Shanghai. The results show that the concentrations of chemical species in the river water at Rongpu Temple Station were much higher in the summer of 1992 than they were in 1975 and 1993, and the concentrations of atmospheric chemical species were much higher in 1992 than they were in 1980. The environment of the north slope of Mt. Qomolangma was therefore heavily polluted before and/or during the summer of 1992, possibly due to the Kuwait oil fires in 1990 and 1991.  相似文献   

13.
Ground-based measurements are essential for understanding alpine glacier dynamics, especially in remote regions where in-situ measurements are extremely limited. From 1 May to 22 July 2005 (the spring-summer period), and from 2 October 2007 to 20 January 2008 (the autumn-winter period), surface radiation as well as meteorological variables were measured over the accumulation zone on the East Rongbuk Glacier of Mt. Qomolangma/Everest at an elevation of 6560 m a.s.l. by using an automatic weather station (AWS). The results show that surface meteorological and radiative characteristics were controlled by two major synoptic circulation regimes: the southwesterly Indian monsoon regime in summer and the westerlies in winter. At the AWS site on the East Rongbuk Glacier, north or northwest winds prevailed with high wind speed (up to 35 m s-1 in January) in winter while south or southeast winds predominated after the onset of the southwesterly Indian monsoon with relatively low wind speed in summer. Intensity of incoming shortwave radiation was extremely high due to the high elevation, multiple reflections between the snow/ice surface and clouds, and the high reflective surrounding surface. These factors also caused the observed 10-min mean solar radiation fluxes around local noon to be frequently higher than the solar constant from May to July 2005. The mean surface albedo ranged from 0.72 during the spring-summer period to 0.69 during the autumn-winter period. The atmospheric incoming longwave radiation was greatly affected by the cloud condition and atmospheric moisture content. The overall impact of clouds on the net all-wave radiation balance was negative in the Mt. Qomolangma region. The daily mean net all-wave radiation was positive during the entire spring-summer period and mostly positive during the autumn-winter period except for a few overcast days. On monthly basis, the net all-wave radiation was always positive.  相似文献   

14.
针对2016年湖北梅雨期3次(“6·19”、“7·5”和“7·19”)暴雨过程,首先对比了汉口站探空数据与汉口、咸宁两个风廓线雷达站水平风速、风向,发现“6·19”和“7·5”过程汉口风廓线雷达站3 km以下水平风速和探空数据较为接近,而3次过程中咸宁风廓线雷达站8 km以下水平风向、风速和汉口站探空数据基本吻合。在此基础上利用风廓线雷达资料并结合常规、加密自动气象站资料,对3次过程中水平风场、平均垂直速度及其变率、水平风速垂直切变、大气折射率结构常数(C_(n)^(2))等进行分析。结果表明:(1)降水开始前西南风速明显增大,中层干冷空气入侵和地面冷池形成的中尺度偏东气流是“6·19”过程50站出现大于等于17.2 m·s^(-1)大风的主要原因,“7·5”和“7·19”过程西南急流长时间维持及1 km以下的偏东气流则是短时强降水持续时间较长的诱因;(2)梅雨期暴雨期间风廓线雷达观测的水平风速垂直切变、平均垂直速度及其变率随高度变化较小,较强上升运动区域主要集中在4 km高度以下;(3)C_(n)^(2)显示强降水发生前大气水汽含量有一增加过程,且整层水汽含量深厚,C_(n)^(2)大值区的消失对应降水结束。  相似文献   

15.
于波  李桑  郝翠  刘郁珏  杜佳  卢俐 《大气科学》2022,46(1):181-190
受特殊地理环境影响,北京地区冬季降雪常与边界层东风相伴,边界层东风所引起的水汽输送和动力辐合效应对降雪发生发展有重要意义.不同于已有边界层东风对平原地区降雪影响的研究,本文结合2022年冬奥会北京延庆赛区的地形特征,对比相似天气背景下不同温湿特性、不同发展高度的边界层东风对降雪的作用机制,研究表明:(1)途经渤海湾的路...  相似文献   

16.
2018年上海合作组织青岛峰会(以下简称“上合青岛峰会”)于6月9—10日在青岛召开,会议筹备、运行及开幕式等活动对精细化气象服务要求较高。青岛市气象局通过升级改造自动气象站,新增海上浮球观测站,申请卫星加密观测,完善了会议场馆及周边气象综合探测系统;本地化了短时临近系统及海雾客观预报系统,建立了高影响天气个例库,实现了天空状况、能见度、降水量的精细化、无缝隙预报;开发了格点预报产品制作平台,服务于上合青岛峰会决策的显示服务平台和手机APP,实现监测、预报一体,预报预警高效制作分发;高度重视网络安全运行维护保障。组建专家服务团队,充分利用国内最新科技成果,确定服务重点,明确责任主体,坚持科学服务策略,通过服务网站、现场服务、电话、会商、传真等多种手段为政府会议相关官员、会议筹备成员单位等提供了精细化的气象服务,出色地完成了上合青岛峰会气象保障任务。  相似文献   

17.
李锐  李正强  赵坤  孙业乐 《大气科学》2023,47(1):174-184
为顺应新一轮科技发展革命,国家自然科学基金委员会积极开展了以“优化学科布局”为主要任务之一的改革工作,学科申请代码的调整是该任务的重要组成部分和切入点。从2019年到2022年,国家自然科学基金委大气科学学科对二级申请代码进行了调整,将与大气探测相关的研究归并至“D0509大气观测、遥感和探测技术与方法”,并将其定义为“支撑技术”板块,以区别于“分支学科”和“发展领域”。本文对D0509二级代码的修订过程进行了介绍,并从大气观测、遥感和探测技术与方法的重要性、内涵与外延、发展趋势等视角,对相关的研究方向和关键词进行了解读。特别是从学科基础层面和具体应用层面两个维度,对D0509下设的六大研究方向,以及各方向的关键词进行分析,有助于申请人和评审专家根据自己的学术背景准确挑选关键词,以利于申请书的精准评审。本文可以为科研人员在基金申请过程中关键词的选择提供参考。  相似文献   

18.
In weather sciences, the two specific terms “storm” and “cyclone” frequently appear in literature and usually refer to the violent nature of a number of weather systems characterized by central low pressure, strong winds, large precipitation amounts in the form of rain, freezing rain, or snow, as well as thunder and lightning. But what is the connection between these two specific terms? In this paper, the historic evolutions of the terms “storm” and “cyclone” are reviewed from the perspective of...  相似文献   

19.
本文试用中国清代天气记录《晴雨录》资料复原南京、苏州、杭州三地18世纪期间夏季(6—8月)和5、6、7、8各月份的逐年降水量序列。文中介绍了这份古代气象资料的特点和对它作数值编码处理的方法;详述了将这种文字记述资料换算成月降水量值的步骤及其科学依据;并对所获得的降水量序列的可信性作了初步对比与讨论。  相似文献   

20.
The complete form of the vertical vorticity tendency equation (the complete-form vorticity equation) is derived from the Ertel potential vorticity equation to contain thermodynamic factors. In this study, a new complete-form vorticity equation, which has the same form as the original complete-form vorticity equation, is deduced from the absolute vorticity vector equation combined with the continuity equation and the expression of three-dimensional (3D) entropy gradient. By comparing the complete-form vorticity equation with the classical vertical vorticity equation, it is found that regardless of whether or not the isentropic surface is tilting, the two vorticity equations are in essence the same. The “baroclinic term” of the complete-form vorticity equation is exactly equal to the solenoidal term of the classical one, and there is a significant amount of cancellation between the two baroclinic items (the “slantwise term” and the horizontal vorticity change term) in the complete-form vorticity equation. In operational weather analysis, the tilt of the isentropic surface can be diagnosed according to the density of the isotherm on the upper-level isobaric map. For synoptic-scale motion, the vertical vorticity produced by the tilt of the isentropic surface is due to the contribution of atmospheric baroclinicity, which is measured by the solenoid. The 3D solenoid is parallel to the isentropic surface, so the more tilted the isentropic surface, the bigger the projection of the 3D solenoid in the vertical direction. The baroclinic contribution can be interpreted based on the PV thinking theory, but the relationship between the vorticity field and the potential vorticity field is not immediate.  相似文献   

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