Monitoring and Prediction of the Earth’s Climate: a future Perspective
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Carlos Granell, Laura Diaz, Michael Gould, Service-oriented applications for environmental models: Reusable geospatial services, Environmental Modelling & Software, Volume 25, Issue 2, February 2010, Pages 182-198, ISSN 1364-8152, DOI: 10.1016/j.envsoft.2009.08.005. (http://www.sciencedirect.com/science/article/B6VHC-4X8BV4J-1/2/23550c11679491c57b81b36c56802505) Abstract: Environmental modelling often requires a long iterative process of sourcing, reformatting, analyzing, and introducing various types of data into the model. Much of the data to be analyzed are geospatial data--digital terrain models (DTM), river basin boundaries, snow cover from satellite imagery, etc.--and so the modelling workflow typically involves the use of multiple desktop GIS and remote sensing software packages, with limited compatibility among them. Recent advances in service-oriented architectures (SOA) are allowing users to migrate from dedicated desktop solutions to on-line, loosely coupled, and standards-based services which accept source data, process them, and pass results as basic parameters to other intermediate services and/or then to the main model, which also may be made available on-line. This contribution presents a service-oriented application that addresses the issues of data accessibility and service interoperability for environmental models. Key model capabilities are implemented as geospatial services, which are combined to form complex services, and may be reused in other similar contexts. This work was carried out under the auspices of the AWARE project funded by the European programme Global Monitoring for Environment and Security (GMES). We show results of the service-oriented application applied to alpine runoff models, including the use of geospatial services facilitating discovery, access, processing and visualization of geospatial data in a distributed manner. Keywords: Geospatial processing services; Application and service integration; Service reuse; Environmental models; Service-oriented architecture, SOA; Spatial data infrastructure, SDI
(http://www.sciencedirect.com/science/article/B6TBG-4772MR2-7V/2/3e7e4557ec407df22d96d616622bbf7e) John A. Robbins, D.N. Edgington, Determination of recent sedimentation rates in Lake Michigan using Pb-210 and Cs-137, Geochimica et Cosmochimica Acta, Volume 39, Issue 3, March 1975, Pages 285-304, ISSN 0016-7037, DOI: 10.1016/0016-7037(75)90198-2. (http://www.sciencedirect.com/science/article/B6V66-4893VDT-BV/2/0818d3eeac1d8d5198b93733aaffbd8d) Abstract: This paper describes the use of 210Pb and 137Cs radioactivity measurements to determine the rates of sedimentation in the Great Lakes. Cores from eight locations in Lake Michigan were chosen for examination to cover as wide as possible a range of sedimentation rates and representative sedimentary environments. The surficial 210Pb activity in the sediments varies between 7 and 23 pCi/g dry wt and its profile in each core shows the expected exponential decrease with depth consistent with the assumption of uniform sedimentation rate over the last hundred years and secular equilibrium between supported 210Pb and 226Ra (0.5-1.0 pCi/g dry wt). Companion measurements of 137Cs indicate that the coring technique satisfactorily recovered the uppermost levels of the deposit and that the mobility of both radionuclides within the sediment is probably small. Based on the limited number of cores analyzed to date, it appears that modern sedimentation rates are not very different from average rates for the last 7000 yr. The excess 210Pb appears to originate primarily from atmospheric fallout, but a further inventory of the 210Pb distribution over the lake bottom must be made to properly assess the significance of other sources. The spatial distributions of both 137Cs and 210Pb at certain stations suggest that the mode of transport of these radionuclides are comparable and involve attachment to settling particles. A mathematical model is developed which accounts for the observed limited mobility of both 210Pb and 137Cs in several of the cores in terms of post-depositional redistribution by physical or biological mixing processes.
(http://www.sciencedirect.com/science/article/B6V6V-4Y52J43-3/2/70a5e2a1021cb0d0f1705c7c83272572) Abstract: The ability to detect and quantify changes in the Earth's environment depends on sensors that can provide calibrated, consistent measurements of the Earth's surface features through time. A critical step in this process is to put image data from different sensors onto a common radiometric scale. This work focuses on monitoring the long-term on-orbit calibration stability of the Terra Moderate Resolution Imaging Spectroradiometer (MODIS) and the Landsat 7 (L7) Enhanced Thematic Mapper Plus (ETM+) sensors using the Committee on Earth Observation Satellites (CEOS) reference standard pseudo-invariant test sites (Libya 4, Mauritania 1/2, Algeria 3, Libya 1, and Algeria 5). These sites have been frequently used as radiometric targets because of their relatively stable surface conditions temporally. This study was performed using all cloud-free calibrated images from the Terra MODIS and the L7 ETM+ sensors, acquired from launch to December 2008. Homogeneous regions of interest (ROI) were selected in the calibrated images and the mean target statistics were derived from sensor measurements in terms of top-of-atmosphere (TOA) reflectance. For each band pair, a set of fitted coefficients (slope and offset) is provided to monitor the long-term stability over very stable pseudo-invariant test sites. The average percent differences in intercept from the long-term trends obtained from the ETM + TOA reflectance estimates relative to the MODIS for all the CEOS reference standard test sites range from 2.5% to 15%. This gives an estimate of the collective differences due to the Relative Spectral Response (RSR) characteristics of each sensor, bi-directional reflectance distribution function (BRDF), spectral signature of the ground target, and atmospheric composition. The lifetime TOA reflectance trends from both sensors over 10 years are extremely stable, changing by no more than 0.4% per year in its TOA reflectance over the CEOS reference standard test sites. Keywords: Landsat 7 ETM+; Terra MODIS; Relative Spectral Response (RSR); Calibration; Characterization; Top-of-atmosphere (TOA) Reflectance; CEOS reference standard test sites; Libya 4; Mauritania 1; Mauritania 2; Algeria 3; Libya 1; Algeria 5
(http://www.sciencedirect.com/science/article/B6V6V-4K427VX-1/2/d8f9855bc59ae8233e2ee9b111252701) Abstract: The remote sensing community puts major efforts into calibration and validation of sensors, measurements, and derived products to quantify and reduce uncertainties. Given recent advances in instrument design, radiometric calibration, atmospheric correction, algorithm development, product development, validation, and delivery, the lack of standardization of reflectance terminology and products becomes a considerable source of error. This article provides full access to the basic concept and definitions of reflectance quantities, as given by Nicodemus et al. [Nicodemus, F.E., Richmond, J.C., Hsia, J.J., Ginsberg, I.W., and Limperis, T. (1977). Geometrical Considerations and Nomenclature for Reflectance. In: National Bureau of Standards, US Department of Commerce, Washington, D.C. URL: http://physics.nist.gov/Divisions/Div844/facilities/specphoto/pdf/geoConsid.pdf.] and Martonchik et al. [Martonchik, J.V., Bruegge, C.J., and Strahler, A. (2000). A review of reflectance nomenclature used in remote sensing. Remote Sensing Reviews, 19, 9-20.]. Reflectance terms such as BRDF, HDRF, BRF, BHR, DHR, black-sky albedo, white-sky albedo, and blue-sky albedo are defined, explained, and exemplified, while separating conceptual from measurable quantities. We use selected examples from the peer-reviewed literature to demonstrate that very often the current use of reflectance terminology does not fulfill physical standards and can lead to systematic errors. Secondly, the paper highlights the importance of a proper usage of definitions through quantitative comparison of different reflectance products with special emphasis on wavelength dependent effects. Reflectance quantities acquired under hemispherical illumination conditions (i.e., all outdoor measurements) depend not only on the scattering properties of the observed surface, but as well on atmospheric conditions, the object's surroundings, and the topography, with distinct expression of these effects in different wavelengths. We exemplify differences between the hemispherical and directional illumination quantities, based on observations (i.e., MISR), and on reflectance simulations of natural surfaces (i.e., vegetation canopy and snow cover). In order to improve the current situation of frequent ambiguous usage of reflectance terms and quantities, we suggest standardizing the terminology in reflectance product descriptions and that the community carefully utilizes the proposed reflectance terminology in scientific publications. Keywords: Reflectance; Terminology; Definition; Nomenclature; BRDF; Spectrodirectional; Vegetation; Snow
(http://www.sciencedirect.com/science/article/B8H4J-4NRF347-D/2/6f3accb919aabfa1b4cf8b91fe53fcf2) Abstract: Cortically lesioned, intact, and hippocampally lesioned albino rats were given posttrial injections of strychnine sulphate (1 mg/kg or .33 mg/kg) or saline. Animals with hippocampal lesions showed deficits in Lashley III maze-habit acquisition but not simultaneous visual discrimination. No retention deficits of post-operatively learned maze habits were observed even after long intervals. Hyperactivity in Ss with hippocampal lesions could not adequately account for deficits in maze performance. Posttrial injection of strychnine had no effect on learning. The data suggest that hippocampus is involved in formation, but not storage, of memory traces. Consolidation of traces was neither facilitated nor attenuated by strychnine. (PsycINFO Database Record (c) 2006 APA, all rights reserved) Keywords: RAT/DRUG EFFECTS IN, STRYCHNINE &; HIPPOCAMPAL LESIONS &; MAZE BEHAVIOR, RAT; MEMORY/SHORT TERM, HIPPOCAMPAL LESIONS &; STRYCHNINE &; MAZE BEHAVIOR, RAT; LEARNING/MAZE, HIPPOCAMPAL LESIONS &; STRYCHNINE, RAT
(http://www.sciencedirect.com/science/article/B6VS0-4FTGCHK-N/2/ab5f019ab081d134419be9827383cc92) P. Ehrenfreund, N. Peter, K.U. Schrogl, J.M. Logsdon, Cross-cultural management supporting global space exploration, Acta Astronautica, Volume 66, Issues 1-2, January-February 2010, Pages 245-256, ISSN 0094-5765, DOI: 10.1016/j.actaastro.2009.05.030. (http://www.sciencedirect.com/science/article/B6V1N-4WXXV49-1/2/fb0b4c7a4121f877b8e7c1c74a77ab2b) Abstract: A new era of space exploration has begun that may soon expand into a global endeavor mainly driven by socio-economic motives. Currently the main space powers, namely the United States, Russia, Europe, Japan, Canada as well as new rising space powers China and India, are pursuing national exploration programs to explore robotically and later with humans the Earth-Moon-Mars space. New axes of partnerships and cooperation mechanisms have emerged in the last decades. However, in order to achieve highly ambitious goals such as establishing human bases on the Moon, journeys to Mars and the construction of new infrastructures in space, international space cooperation has to be optimized to reduce costs and reap the benefits of worldwide expertise. Future ambitious space exploration endeavors are a long-term undertaking that could influence countries to look beyond their own interests and see the advantages that a larger program can bring. This paper provides new concepts for managing global space exploration in the framework of cross-cultural management, an element often neglected in the planning of future partnerships. Keywords: Cross-cultural management; Space policy; Space exploration; International cooperation; Cultural dimension
(http://www.sciencedirect.com/science/article/B6V6V-4NKJ1K0-1/2/29e421e7954752424d9bfbf9b697ca68) Abstract: This article describes the algorithmic principles used to generate LAI, fAPAR and fCover estimates from VEGETATION observations. These biophysical variables are produced globally at 10 days temporal sampling interval under lat-lon projection at 1/112[degree sign] spatial resolution. After a brief description of the VEGETATION sensors, radiometric calibration process, based on vicarious desertic targets is first presented. The cloud screening algorithm was then fine tuned using a global network of cloudiness observations. Atmospheric correction is then achieved using the SMAC code with inputs coming from meteorological values of pressure, ozone and water vapour. Aerosol optical thickness is derived from MODIS climatology assuming continental aerosol type. The Roujean BRDF model is then adjusted for red, near infrared and short wave infrared bands used to the remaining cloud free observations collected over a time window of +/- 15 days. Outliers due to possible cloud contamination or residual atmospheric correction are iteratively eliminated and prior information is used to get more robust estimates of the three BRDF kernel coefficients. Nadir viewing top of canopy reflectance in the three bands is input to the biophysical algorithm to compute the products at 10 days sampling interval. This algorithm is based on training neural networks over SAIL + PROPSPECT radiative transfer model simulations for each biophysical variable. Details on the way the training data base was generated and the neural network designed and calibrated are presented. Finally, theoretical performances are discussed. Validation over ground measurement data sets and inter-comparison with other similar biophysical products are presented and discussed in a companion paper. The CYCLOPES products and associated detailed documentation are available at http://postel.mediasfrance.org. Keywords: LAI; fAPAR; fCover; Biophysical variables; Global products; BRDF; Cloud; Radiative transfer; Neural network
(http://www.sciencedirect.com/science/article/B8CWG-4P188SP-5/2/f9a1226e5c84bfa37fcc1b3e477413e8) Ingrid Puillat, Roland Person, Claude Leveque, Jean-Francois Drogou, Michael Diepenbroek, Pierre Garreau, Christoph Waldmann, Yves Auffret, Standardization prospective in ESONET NoE and a possible implementation on the ANTARES Site, Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Volume 602, Issue 1, Proceedings of the 3rd International Workshop on a Very Large Volume Neutrino Telescope for the Mediterranean Sea, 11 April 2009, Pages 240-245, ISSN 0168-9002, DOI: 10.1016/j.nima.2008.12.242. (http://www.sciencedirect.com/science/article/B6TJM-4VDY7VG-2/2/68574f7f65345401ec9b3c5bc8a2bf80) Abstract: ESONET is a Multidisciplinary European Network of Excellence (NoE) associating 50 partners from 14 countries and more than 300 scientists and engineers and dedicated to the lasting integration of research and development in deep sea observatories in Europe. Amongst other actions, it works at establishing seafloor infrastructure that will provide platforms for instrumentation deployed throughout the water column and the geosphere below in a standard manner. Those platforms will provide power for instruments and real-time two-way data communications. This preparatory phase of observatory implementation is intended to select the most suitable standards in order to develop observatories that are interoperable between themselves and which would be able to benefit from the common sharing of facilities. After the ESONET Best Practices Workshop held in Bremen at the end of January 2008, the state of art has been set and some groups working on key standardization topics have been constituted to manage standardization plans. Some outputs are presented hereafter. Those plans will be implemented and tested in the recently-selected four so-called ESONET Demonstration Missions. The ANTARES Site as an ESONET regional node offers some facilities for the next call for demonstration missions. Scientific interest is briefly explained, with a specific focus on needs for oceanography. The technical possibility of new instrument implementation via a secondary junction box is then presented. Keywords: Deep sea observatories; Junction box; Data management; Standardization; Sensor registry; Northern current; Ligurian sea
(http://www.sciencedirect.com/science/article/B6V3S-4XC57NJ-1/2/468158c39902c99ead41e9d7f7d6607a) Abstract: DORIS is one of the four geodetic space techniques participating to the Global Geodetic Observing System (GGOS). Since the early development of this system, the Institut Geographique National played a specific and active role. Within, the International DORIS Service (IDS), IGN is in a particular position. While it is responsible for the installation and the maintenance of the DORIS ground tracking stations, it also handles one of the two IDS data center delivering DORIS data and products and has been an IDS Analysis Center for years, providing all possible IDS products, in particular the latest ignwd08 time series in preparation of ITRF2008. This paper explains the different aspects of the IGN contribution to IDS from an historical point of view, presents current activities and scientific results and provides a perspective for future activities. Recent DORIS results show a 10 mm precision or better when more than four DORIS satellites are available. Comparisons between recent DORIS solutions (ign07d02 and ign09d02) and past ITRF realizations show that errors are shared between the DORIS and the ITRF realizations. Some problems related to DORIS data processing are also discussed and possible ways to solve them in the future are discussed. In particular, we can now reject the tropospheric origin of the problem detected in the Envisat data after the software upload of October 12, 2004. A few applications in geodesy (terrestrial reference frame, Earth's polar motion) and geophysics are also discussed as a natural extension of these service-type activities. Keywords: DORIS; Geodesy; Geophysics; Analysis center; Global data center
(http://www.sciencedirect.com/science/article/B9636-4SY6CH0-N3/2/85b10ad0325c41db39a29dc216f2518f) Abstract: Satellite remote sensing instruments provide a unique perspective on the state and dynamic changes occurring in land, coastal, and oceanic ecosystems. They also provide detailed global observations of both natural and anthropogenically induced changes in land surface, atmospheric and climatic drivers that often determine ecological health, sustainability, and dislocations. Together with more specific in situ observations, space-based remote sensing of the global environment enables the investigation of the interplay between the different components of the earth/climate system as also the interaction between local and global processes. Moreover, these data facilitate the construction of numerical models that attempt to capture the dynamics of changes to and impacts on global ecology. Time series of observations and advanced visualization tools enhance our understanding of global ecological processes, several examples of which are presented here. This article is not intended to be a treatise on ecology or on the technological details of satellite remote sensing instruments. Rather, we hope it provides the reader with a sense of the current capabilities of satellite remote sensing methods as it applies to the monitoring of the global biosphere. For additional detail, the reader is pointed to a list of comprehensive references in the form of published papers as well as Internet web sites. While extensive use is made of readily available `public domain' material and data from NASA's Earth Observing System series of satellites and predecessor space-based platforms, it is underscored that many other space agencies of other countries and regions increasingly have advanced capabilities to monitor the global biosphere from space. Keywords: Biosphere; Climate change; Coastal ecosystems; Ecosystem disturbances; Ecosystems; Environment; Global ecology; Global observations; Global warming; Land cover change; Large-scale impacts; Oceanic ecosystems; Phytoplankton blooms; Remote sensing; Satellite instruments; Satellite monitoring; Satellite sensors; Vegetation
(http://www.sciencedirect.com/science/article/B6V2J-47S62YX-3/2/5f403272317d254a6028b11e23405452) Yola Georgiadou, Jantien Stoter, Studying the use of geo-information in government - A conceptual framework, Computers, Environment and Urban Systems, Volume 34, Issue 1, January 2010, Pages 70-78, ISSN 0198-9715, DOI: 10.1016/j.compenvurbsys.2009.04.002. (http://www.sciencedirect.com/science/article/B6V9K-4WH6KD2-1/2/be5b21066887b29c5e607ab6c78716d8) Abstract: The aim of this paper is to develop a conceptual framework for studying the use of geo-information and associated technology in government. We first review how geo-information, geo-information technology and people--notions central to geo-information use--are conceptualized in the literature and show that authors view these notions through two contrasting lenses, a market and a polis lens. We then present a people-centered conceptual framework for the study of geo-information use in government. The framework encompasses people's values, people's practices and the rules that people are expected to follow to optimize the use of geo-information. We show how the market and polis lenses illuminate the study of values, practices and rules in different ways resulting in radically different insights. Finally, we illustrate the usefulness of the conceptual framework with preliminary findings from a longitudinal empirical study in the Netherlands. Yüklə 411,35 Kb. Dostları ilə paylaş:
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