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1.
历史文献中的气象记录与气候变化定量重建方法   总被引:2,自引:0,他引:2  
历史文献记载是研究古气候变化的主要代用证据之一, 对于定量重建过去数千年的气候变化序列具有独特价值。本文分析了中国历史文献中气象记录的特点及主要内容, 重点梳理了利用各类记录定量重建气候变化序列的基本方法, 并列举了通过多源记载集成、多时段记录衔接重建过去2000年中国东中部地区温度与干湿变化序列的校准案例; 旨在为客观提取气候变化信息、获取高信度的气候变化数据和进一步发展利用文献记载定量重建气候变化序列的方法提供参考依据。主要认识是:1)历史文献中的气象记录主要有4类: 天气、气象灾害、物候与区域气候特征及其影响记载; 定量重建气候序列的基本方法有: 回归分析、物理模型、分等定级、频次统计、类比分析等, 但各类记录的来源、格式、连续性、详略与定量化程度不一, 导致利用各类记录定量重建气候变化序列的方法也各不相同。2)对根据多源记载或不同方法反演的代用记录进行集成, 利用回归分析、方差匹配、记录影响趋势剔除等校准技术, 加强多源数据的相互插补方法研究, 可解决古代气象记录的漏、缺记问题, 是重建连续气候变化序列的主要途径。  相似文献   

2.
杜玉霞  马巍  赵淑萍  张泽  明姣 《冰川冻土》2016,38(6):1583-1591
在使用激光位移传感器测试冻土位移中,由于测试现场环境条件恶劣,厂家给出的传感器线性度会降低,因此,需要对所有传感器在使用前应模拟使用时的环境条件重新进行标定。为验证激光位移传感器在冻土测试中的适用性,依据德国森萨帕特FT-50RLA220型激光位移传感器的结构、使用特点、技术指标,设计了由控温箱、标定支架、激光位移传感器、量块及数据采集装置组成的标定的装置,进行了不同负温条件下对激光位移传感器标定,并依据标定试验结果进行拟合参数修正,得到不同环境温度下的试验结果的线性度和迟滞特性。试验结果表明:不同的环境温度下,两个激光位移传感器与标准厂家测试曲线存在差异,不同负温条件下标定的两个激光位移传感器的拟合优度R2分别为0.999和1;线性度最大值分别为0.88%FS和0.32%FS。  相似文献   

3.
沈颖  刘继民  赵淑萍 《冰川冻土》2012,34(4):891-897
介绍了用于低温测量的单点热敏电阻温度传感器及多点测温电缆的结构和使用特点.将2003年埋设在青藏高原冻土区某测温孔的一根测温电缆于2010年取出, 在实验室重新进行温度标定试验.为了保证2003年和2010年标定时的条件完全相同, 并将2010年标定时的温度点设置成与2003年标定时的完全一致.利用2003年的标定系数和2010年标定时得到的电阻值反算温度值、 并与标定温度值对比, 发现8个温度传感器的温度漂移均为正漂移, 最大值为0.032 ℃, 年漂移最大值为0.0046 ℃, 低于热敏电阻温度传感器本身的测温精度值0.05 ℃, 从而验证了SKLFSE-TS型热敏电阻温度传感器以及用其制作而成多点测温电缆的长期稳定性.  相似文献   

4.
Earth Science data and particularly the satellite images supplies important information on status and dynamics of earth covering vegetation. The development of environment applications is a challenge for Grid technologies and software development methodologies. This paper exemplifies and experiments the development of the GreenView application over SEE-GRID infrastructure by the Grid Application Development Methodology. The paper highlights through the ESIP and gProcess platforms based methodology the steps of the GreenView development. The application reveals three main functionalities—refinement of the satellite image resolution, field measurements based calibration and satellite image classification by vegetation index computation. A few experiments evaluate the execution time of the tasks at four sites of the SEE-GRID infrastructure.  相似文献   

5.
李英奎  杨玮琳  陈鑫  刘强  许向科 《冰川冻土》2022,44(4):1231-1247
冰川模型已广泛应用于预测未来的冰川变化。随着冰川地貌制图、测年和古气候研究的不断发展,冰川模型也逐渐用于模拟古冰川变化、估算古冰川发育时期的气候信息和探讨古冰川演化的气候驱动因素。本文综述用于古冰川模拟的两类模型:地貌-冰面剖面形态模型和物质平衡-冰川动力耦合模型,介绍不同冰川模型的原理、用于古冰川模拟的流程和利用地貌体进行模型参数校验的方法。在此基础上,以青藏高原及其周边山地为例,总结利用冰川模型恢复古冰川的范围、体积、平衡线等参数,估算不同冰川发育时期的温度和降水,以及评估测年数据及其恢复的古冰川期次和规模的案例研究。最后指出了利用冰川模型进行古冰川模拟研究存在的问题和未来发展趋势,为进一步加强和改进冰川模型在古冰川模拟研究中的应用,恢复古冰川的规模、演化过程及其气候驱动机制奠定基础。  相似文献   

6.
在滑坡动态变形监测中一般会在滑坡体上布置多个传感器,以进行综合观测.目前的监测模型仅依靠某个关键点的数据进行评判分析,容易造成原始数据信息的流失,且以往的研究多集中于监测数据的整合,并未考虑传感器自身的因素,引起融合结果的不精确.为了克服以上不足,引人多传感器估值融合理论,选用误差均方差为评价指标,证明多源数据融合方法...  相似文献   

7.

为了促进高光谱技术在地震有关气体监测中的应用, 本文选取对近地表信息敏感度较强的近红外高光谱传感器TROPOMI的二级产品数据, 分析研究了青藏高原东北缘和川滇地区地震相关气体时空特征及其与构造和地震活动关系, 评价了近红外传感器在地震有关气体监测中的应用效果和应用前景。结果表明: TROPOMI反演的研究区CH4和CO气体在时间上呈现明显的季节变化, 受气候变化、地貌、人类活动等影响; 空间上在银川、渭河和四川盆地表现为高值, 受地质背景、地形地貌和人类活动等因素影响。目前近红外高光谱传感器在时间分辨率和有效数据量上具有一定的局限性, 但是相对于热红外高光谱传感器, 近红外传感器可以较好地反映气体与近地表构造的关系。未来随着近红外高光谱传感器的应用和发展, 近红外数据可以逐渐弥补热红外传感器数据对近地表信息敏感度低的不足, 提高异常与地震关系的判断力。

  相似文献   

8.
Tower platforms, with instrumentation at six levels above the surface to a height of 30 m, were used to record various atmospheric parameters in the surface layer. Sensors for measuring both mean and fluctuating quantities were used, with the majority of them indigenously built. Soil temperature sensors up to a depth of 30 cm from the surface were among the variables connected to the mean data logger. A PC-based data acquisition system built at the Centre for Atmospheric Sciences, IISc, was used to acquire the data from fast response sensors. This paper reports the various components of a typical MONTBLEX tower observatory and describes the actual experiments carried out in the surface layer at four sites over the monsoon trough region as a part of the MONTBLEX programme. It also describes and discusses several checks made on randomly selected tower data sets acquired during the experiment. Checks made include visual inspection of time traces from various sensors, comparative plots of sensors measuring the same variable, wind and temperature profile plots, calculation of roughness lengths, statistical and stability parameters, diurnal variation of stability parameters, and plots of probability density and energy spectrum for the different sensors. Results from these checks are found to be very encouraging and reveal the potential for further detailed analysis to understand more about surface layer characteristics.  相似文献   

9.
During MONTBLEX 1990, various observational platforms were operated at Kharagpur and the nearby Kalaikunda Air Base. Using the data from all the platforms, one can draw the following conclusions. The temperature and wind data obtained from various sensors have overall compatibility. Sodar wind data indicate the presence of a low level jet at around 300 m above ground. The inversion height may be evaluated from the vertical profile of the sodar back-scatter echo intensity. The sub-synoptic or synoptic scale convergence modulates the inversion height and the presence of cloud-base within the inversion height in turn modulates the sensible heat and momentum fluxes.  相似文献   

10.
WMO第八届阳江国际探空比对辅助遥感综合试验   总被引:1,自引:0,他引:1  
第八届阳江国际探空比对辅助遥感综合试验为分析探空仪系统在高空出入云的温湿特性,评估高层云红外辐射对温度传感器的影响以及湿度传感器的系统偏差提供有力帮助。通过试验,还评估了国产X波段双偏振雷达与毫米波云雷达的优缺点和性能差异,以及国产多普勒激光雷达、微脉冲激光雷达的探测性能和应用能力,在改进微波辐射计温湿反演算法、X波段偏振雷达参数的云中粒子相态模糊逻辑识别算法,以及多普勒天气雷达风场反演、云分类算法、高空业务测风算法等方面开展广泛研究并取得一定进展。试验还利用先进的各类遥感设备对阳江热带地区的云、局地对流以及海陆风系统的结构进行了观测和分析,取得了较好的研究结果。  相似文献   

11.
Nowadays, thanks to the hardware costs reduction everyone at home owns at least one hi-technology devices to support life quality. This paper proposes a new methodology to analyse the indoor air quality with a cheap and third-age-dedicated device. A new prototype, called Home Pollution Embedded System (HOPES), was developed to give simple and understandable information, also comprehensible for people with cognitive problems or that are not familiar with new technologies. The device gathers pollutants data and displays to the user different air pollutants concentrations, from toxics gasses up to explosives. Moreover, an overall air quality index has been elaborated and is displayed by HOPES with lights and numerical information. HOPES is an Internet of things device that works in real time and that can be connected to the web and to a geographic information system platform to add spatial information of each pollutant. The hardware architecture employs a set of gas semiconductor sensors and an IR particulate matter sensor. Experimental results demonstrated that HOPES has an accurate sensor response and is suitable to be used with the proposed indices. In fact, despite of the poor-selective metal oxide sensors, the results highlighted how it is possible to get useful air quality information with a cheap device. However, the system needs more tests to validate the sensors array with different substances.  相似文献   

12.
基于原状土柱土壤水分传感器率定方法的研究   总被引:2,自引:1,他引:2       下载免费PDF全文
土壤水分传感器在现场安装后,需要针对现场土壤状况对其进行率定,以便校准率定关系。在工程实践中,土壤水分传感器现场率定是一项步骤繁杂、操作要求高、现场取土难度大、耗时较长的一项工作,严重困扰工程项目的实施。开展基于原状土柱率定土壤水分传感器研究,通过现场采集原状土柱,在实验室浸泡至饱和后取出,让土壤水分自然散失,用称重法定期称量原状土柱重量,同时记录土壤水分传感器原始测量值,以此来研究土壤水分传感器的工程率定问题,探讨提高现场安装的土壤水分传感器率定效率的方法,具有现实意义。  相似文献   

13.
黄龙钙华210Pb计年与现代沉积的环境变化研究   总被引:2,自引:2,他引:2  
本文以黄龙钙华岩芯为主要研究对象, 利用210Pb定年技术在测定年轻碳酸盐样品短时间尺度上的优势建立了研究区近100年来高精度的年代标尺及环境记录; 通过碳氧稳定同位素的分析, 讨论了钙华稳定同位素记录与器测气候数据的相关性特征, 并与其他定年技术所获得的结果进行了相互验证。研究区钙华δ18O在1908~2004年时段内的变化范围为?12.13‰~?10.42‰, 平均值为?11.23‰, 变化幅度达到了1.7‰。同属西南季风区、由于海拔效应和距离水汽来源远近不同等因素的影响, 在同时段内黄龙钙华δ18O的变化范围和变化幅度都比董歌洞和Kahf Defore洞的δ18O记录要大, 说明处于中纬度、高海拔的黄龙钙华相对于低海拔的董歌洞和Kahf Defore洞石笋对气候环境的响应可能更加敏感。  相似文献   

14.
Geographic information provides the basis for many types of decisions ranging from simple path finding, to the sustainable management of environmental conditions. Producing such information is a time consuming and costly endeavor. Data sharing on the web is an avenue to increase the efficiency of the practices. This paper scientifically examines the new emerging technologies namely, internet, geographic markup language (GML), and observation and measurement models, to construct an interoperable repository for air quality sensors measurements. The paper also elaborates on the design and implementation of a web-based air quality information system (AQIS) for the city of Tehran. In-situ sensors measure ozone (C3), carbon monoxide (CO), sulfur dioxide (SC2), nitrogen dioxide (NC2) and particulate matters (PM) in polluted metropolitans. Providing real-time air quality information can improve the decisions of the pertinent environmental organizations. Using GML for encoding sensors observations makes it possible to build an interoperable repository that is independent of platforms and vendors. Providing query possibilities based on monitoring stations, sensor names (pollutants), date and time intervals, and spatial query on the AQIS interfaces are the major functions of this system. Although standardized, it was concluded that the use of GML as data format increases the size of GML document. In addition, the developed system provides no map based results for the clients. Therefore, it is required to be improved by adding more GIS functions.  相似文献   

15.
在微地震监测中有效微地震信号的识别是关键步骤。常规的微地震有效信号识别方法基于单道长短时窗能量比,受噪音影响较大,对于信噪比较低的事件无法准确识别。利用多道记录数据之间的信号相关性好而信号与噪音相关性差的特点,通过记录道自相关求取总能量和相邻记录互相关求取信号能量,以有效信号能量所占比即含信能量比作为门槛值进行有效信号识别,信号识别过程中利用多道互相关对噪音进行了有效压制,提高了微地震信号识别的压噪能力,通过模型数据和实际资料处理验证了方法的有效性。  相似文献   

16.
气态烃快速探测系统在海洋油气勘探中的应用   总被引:9,自引:0,他引:9  
气态烃快速探测系统以高灵敏度化学传感器为技术突破,与其配套装置可实现海洋烃类快速探测与现场处理一体化;可实现对不同层次,不同尺度、不同精度数据的综合解释和烃类异常的现场圈定。研制出的化学传感器及其配套装置具有:高灵敏度、高稳定性、小型轻便、低功耗、易操作、能适应恶劣海况条件,同时测定痕量气态烃和多种参数的特点。这种基于化学传感器原理的便携式高灵敏度气态烃现场测定系统,可以现场快速测定样品中的超微量甲烷、乙烷、丙烷及氢气的组分含量,并通过引入气体色谱柱和信号保真处理,使整个系统具有较好的选择性,从而实现了混合气体的高灵敏度快速分析。  相似文献   

17.
Chironomids (non-biting midges) can provide accurate climate reconstructions from the Late Glacial to the present. Until now, anoxic lakes have been avoided for temperature reconstructions since chironomid assemblages are sensitive to changes in oxygen concentrations in the hypolimnion. However, anoxic lakes may have varved sediments, providing the possibility for near-annual climate reconstructions. Here, we tested the applicability of two calibration methods to reconstruct mean July air temperatures from chironomid assemblages preserved in the sediments of the anoxic Seebergsee located in the northern Swiss Alps: a calibration-in-space approach and a calibration-in-time approach. The calibration-in-space approach (i.e. chironomid assemblages from surficial lake sediments (0–1 cm) calibrated against meteorological data) provided accurate inferences (i.e. similar temperature changes as measured at the closest meteorological station, and at regional stations) in the Seebergsee stratigraphy until anoxia increased in the lake. With the increase of anoxia, the chironomid-inferred temperatures were generally colder than measured temperatures. A calibration-in-time approach (i.e. calibration of chironomid assemblages in a time series against instrumental data from the closest meteorological station) provided accurate reconstructions (i.e. similar to the regional records) for the past 100 years, including the time period of inferred anoxia. However, its applicability should be further tested on longer temporal scales.  相似文献   

18.
Numerous modeling approaches are available to provide insight into the relationship between climate change and groundwater recharge. However, several aspects of how hydrological model choice and structure affect recharge predictions have not been fully explored, unlike the well-established variability of climate model chains—combination of global climate models (GCM) and regional climate models (RCM). Furthermore, the influence on predictions related to subsoil parameterization and the variability of observation data employed during calibration remain unclear. This paper compares and quantifies these different sources of uncertainty in a systematic way. The described numerical experiment is based on a heterogeneous two-dimensional reference model. Four simpler models were calibrated against the output of the reference model, and recharge predictions of both reference and simpler models were compared to evaluate the effect of model structure on climate-change impact studies. The results highlight that model simplification leads to different recharge rates under climate change, especially under extreme conditions, although the different models performed similarly under historical climate conditions. Extreme weather conditions lead to model bias in the predictions and therefore must be considered. Consequently, the chosen calibration strategy is important and, if possible, the calibration data set should include climatic extremes in order to minimise model bias introduced by the calibration. The results strongly suggest that ensembles of climate projections should be coupled with ensembles of hydrogeological models to produce credible predictions of future recharge and with the associated uncertainties.  相似文献   

19.
开都河源区气候变化及径流响应   总被引:12,自引:0,他引:12  
应用巴音布鲁克水文站和气象站1960-2005年的观测资料,分析了开都河流域源区气温和降水的变化特征以及径流对气候变化的响应.结果表明:近46 a来开都河源区气温总体呈上升趋势,而降水量年际波动较大,降水量自1989年以来增加显著,降水和气温是开都河源区径流量变化的主要影响因素.年降水量与年径流量的单相关系数最大,为0.73;年平均气温与年径流量的相关系数为0.36.在降水量不变的情况下,径流量随气温升高而减少;在气温不变的情况下,径流量随降水量的增加而增加;而在降水量和气温都增加的情况下,径流量将有所增加.  相似文献   

20.
《Geodinamica Acta》2013,26(1-2):35-52
Non-invasive techniques to continuously measure the rates or intensities of bedload transport in gravel bed rivers would be quite useful for both research and practice. Since 1986 measurements have been made with piezoelectric bedload impact sensors (PBIS) in several mountain torrents. In 1994 and 1995, a calibration campaign was carried out at a water intake in the Pitzbach mountain stream in Austria, where weighing cells and a water pressure sensor in the settling basin allow sediment transport loads to be determined in 15 minute intervals. Daily averages of PBIS impulses correlate reasonably well with the measured sediment load. Using a linear calibration relation, the relative error between predicted and measured sediment loads is within a factor of about 1.5 to 2. The scatter between PBIS impulses and bedload volumes is much larger if the measurements are averaged over one hour intervals or when the original 15 minute values are considered. A comparison with measurements from the Swiss Erlenbach torrent and from laboratory experiments using sediment particles from the Erlenbach torrent indicates that the proportionality coefficient between PBIS impulses and sediment load appears to depend on site specific conditions, including factors such as flow intensity and sediment properties.  相似文献   

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