Integration of remote sensing data into hydrological models for reservoir management

Abstract

The purpose of this paper is to present the methodology set up to derive catchment soil moisture from Earth Observation (EO) data using microwave spaceborne Synthetic Aperture Radar (SAR) images from ERS satellites and to study the improvements brought about by an assimilation of this information into hydrological models. The methodology used to derive EO data is based on the appropriate selection of land cover types for which the radar signal is mainly sensitive to soil moisture variations. Then a hydrological model is chosen, which can take advantage of the new information brought by remote sensing. The assimilation of soil moisture deduced from EO data into hydrological models is based principally on model parameter updating. The main assumption of this method is that the better the model simulates the current hydrological system, the better the following forecast will be. Another methodology used is a sequential one based on Kalman filtering. These methods have been put forward for use in the European AIMWATER project on the Seine catchment upstream of Paris (France) where dams are operated to alleviate floods in the Paris area.     

North Atlantic climate impact on early late‐glacial climate oscillations in the south‐eastern Alps inferred from a multi‐proxy lake sediment record

High‐resolution multi‐proxy analyses of a sediment core section from Lake Jeserzersee (Saissersee) in the piedmont lobe of the Würmian Drau glacier (Carinthia, Austria) reveal pronounced climatic oscillations during the early late glacial (ca. 18.5–16.0k cal a BP). Diatom‐inferred epilimnetic summer water temperatures show a close correspondence with temperature reconstructions from the adjacent Lake Längsee record and, on a hemispheric scale, with fluctuations of ice‐rafted debris in the North Atlantic. This suggests that North Atlantic climate triggered summer climate variability in the Alps during the early late glacial. The expansion of pine (mainly dwarf pine) between ca. 18.5 and 18.1k cal a BP indicates warming during the so‐called ‘Längsee oscillation’. The subsequent stepwise climate deterioration between ca. 18.1 and 17.6k cal a BP culminated in a tripartite cold period between ca. 17.6 and 16.9k cal a BP with diatom‐inferred summer water temperatures 8.5–10 °C below modern values and a shift from wet to dry conditions. This period probably coincides with a major Alpine glacier advance termed the Gschnitz stadial. A warmer interval between ca. 16.9 and 16.4k cal a BP separates this cold phase from a second, shorter and less pronounced cold phase between ca. 16.4 and 16.0k cal a BP, which is thought to correlate with the Clavadel/Senders glacier advance in the Alps. The following temperature increase, coupled with wet (probably snow‐rich) conditions, caused the expansion of birch during the transition period to the late glacial interstadial. Copyright © 2011 John Wiley & Sons, Ltd.     

The control of maturity and kerogen type on quantitative analytical pyrolysis data

Quantitative pyrolysis-gas chromatography has been performed on 96 kerogen samples isolated from 17 wells on the Norwegian Continental shelf. Petrographic and bulk geochemical measurements were also performed on the samples, and a combined data set of 117 variables for each sample was analysed using principal components analysis (PCA). This approach provides an objective and reproducible means of kerogen characterisation, which can be easily automated. In addition to objective kerogen characterisation and facile visualisation of facies and maturity related chemical trends, the method has the potential to allow objective prediction of key geochemical parameters such as maturity level from pyrogram data.     

Rockburst research at Falconbridge's Strathcona Mine,Sudbury, Canada

Microseismic systems at five mines in the Sudbury Basin provide the basic data for Falconbridge Limited's rockburst research. Daily and long-term analysis of this data as well as underground observations have confirmed the fault-slip mechanism at three mines. A detailed analysis of the complete history of Falconbridge Mine is being conducted and Distinct Element numerical models are being used to simulate both the stick-slip behaviour of faults and the dynamic effects of the induced vibrations on rock and backfill. University research includes acoustic tomographic imaging of the rock mass based on seismic wave propagation and collection of full microseismic waveforms to allow application of advanced seismic and statistical analysis techniques.Formerly with Mines Technical Services, Falconbridge Limited, Sudbury Operations, Falconbridge , Ont., P0M 1S0.Presented at the Fred Leighton Memorial Workshop on Mining Induced Seismicity, Montreal, Canada, August 30, 1987.     

原始数据误差对放样点精度影响的探讨

本文在文献[3]的基础上,进一步探讨了工程测量中原始数据误差对放样点精度影响的问题。首先,讨论了施工控制网中原始数据误差存在的形式、特点以及它们对放样点精度影响的传播规律,并建立了关于相对放样点位精度的矩阵公式。在此基础上,对现有的几种常用放样方法中原始数据误差的影响进行了分析和计算。结果表明,在施工放样测量工作中,应该密切注视原始数据误差的影响,并对此问题提出一些合理的建议。     

Applications of satellite data in the study of monsoon variability

This paper discusses the use of satellite data for studying climate change, with particular emphasis on the inter-annual variability of the Indian southwest monsoon. Precipitation estimates made from INSAT-1B radiance data are shown to bring out the variations that occurred in the monsoon rainfall of 1987 and 1988. Outgoing Longwave Radiation derived from INSAT-1B shows good correspondence with precipitation patterns.     

中国近海海面地形的计算与研究

介绍了海面地形的研究现状,并根据几何水准求得了中国近海的海平面倾斜及其精度.给出应用水文资料计算中国近海海面地形的公式及其计算结果.探讨了由球函数模型计算中国近海海面地形的理论和方法,并对不同方法进行了比较,得出了一些有益的结论.     

国家气象中心数值预报业务的进展

在最近的１５年中，国家气象中心的数值预报业务高速度发展，预报模式从北半球模式发展为全球谱模式，并配套建立了资料同化系统和用于降水预报的有限区预报模式，暴雨和台风预报模式正在研制中。目前数值预报时效已延至７天，Ｔ６３９３丙上时的预报水平已优于的数值预报产品的应用技术在不断改进，最高（低）气温下两天ＭＯＳ预报精度已接近预报员制作的综合预报结果。     

Seismic hazard assessment using intensity point data

The influence of the attenuation model used in seismic hazard assessment in terms of intensity and acceleration is studied. For two sites in central Italy, the catalogue of the actual observed intensities during the last three centuries has been recovered. In the study region, the data collected during a recent seismic sequence give the basis for relating intensity and acceleration. The results show the importance of establishing statistical relationships among the used quantities, based on a representative set of data.     

Uptake of macroelements by the helophytePhalaris arundinacea L.

Helophytes are often incorporated into biological wastewater treatment plants. In favourable situations, they can take up large amounts of nutrients. One helophyte, the reed canarygrass (Phalaris arundinacea L.), is fast growing when supplied with sufficient light and nutrients. Experiments were carried out under natural climatic conditions in small plastic tanks filled with sand with regular additions of a balanced and concentrated nutrient solution. In the growing season (May–October), plant production reached 10.5 kg m^–2 of dry biomass, of which 66% was in the aerial parts. Maximum nutrient uptake capacity was reached just after flowering and before senescence (beginning of October): 49% N, 34% P, 52% K and 34% Mg of the input was fixed in the aerial parts, which are easily harvestable. The corresponding values for the below ground parts were 12%, 10%, 11% and 11% respectively. Excretion of K and Mg has been observed when nutrients are translocated to the storage organs.