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901.
Reports
1990 Watershed Management Symposium Durango, Colorado, USA 相似文献902.
Summary Some important principles of remote sensing using synthetic aperture radar data (SAR data) from the first European Remote Sensing Satellite ERS-1 are explained. Examples illustrate the potential applications of satellite radar information. The possibility of using near-on-line processed remote information for operational purposes is discussed in particular.The satellite information used was received, processed and presented to the visitors of the exhibition which took place as part of the 1992 International Space Year (ISY) at the Bonn offices of the EEC. The BSH and DLR co-operated with DARA and TELEKOM. The intention was to familiarize a broader public with the potential of remote sensing and to stress the necessity of using space technology in combatting environmental problems.
Zum Nutzungspotential von ERS-1-AAR-Daten in naher Echtzeit
Zusammenfassung Im vorliegenden Beitrag werden einige wichtige Grundlagen der Fernerkundung mit SAR-Daten des Ersten Europäischen Fernerkundungssatelliten ERS-1 erläutert und anhand einiger ausgewählter Beispiele Möglichkeiten der Nutzanwendung von Radar-Daten aufgezeigt. Dabei werden besonders die Möglichkeiten eines Nahe-Echtzeit-Einsatzes unter operationellen Gesichtspunkten aufgegriffen und diskutiert.Die verwendeten Daten wurden während einer Präsentation in der Vertretung der Kommission der Europäischen Gemeinschaft in Bonn anläßlich einer Veranstaltung zum Internationalen Weltraumjahr 1992 (ISY) von der BDDN-Fast-Delivery-Station des Bundesamts für Seeschiffahrt und Hydrographie (BSH) in Zusammenarbeit mit der Deutschen Forschungsanstalt für Luft- und Raumfahrt (DLR) und der TELEKOM aufgezeichnet, digital verarbeitet und den Besuchern der Ausstellung vorgestellt. Im Vordergrund stand, das Potential der Fernerkundung einer breiteren Öffentlichkeit zugänglich zu machen und die Notwendigkeit der Raumfahrt zur Erkundung unserer Umwelt zu bekräftigen.
Le potentiel d'application des données ERS-1 SAR en utilisation presqueimmédiate
Résumé Des propriétés importantes du radar d'ouverture synthétique du premier satellite européen ERS-1 d'observation de la Terre sont présentées. Des exemples choisis illustrent les possibilités d'utilisation appliquée de l'information radar. La possibilité d'une exploitation en temps très légèrement différé sous des aspects opérationnels est démontrée.L'information du satellite ERS-1 a été reçue, traitée et archivée lors d'une présentation à la Commission de la Communauté Européene à Bonn. À l'occasion de la manifestation de l'année internationale de l'espace 1992 (ISY), avec le concours de l'Agence Maritime et Hydrographique Fédérale (BSH), en coopération avec le Centre Allemand de Recherches Aérospatiales (DLR) et les TELEKOM. Le but était de présenter au public les possibilités de la télédétection et de montrer la nécessité de l'usage de la technologie pour aider à résoudre les problèmes de l'environment.相似文献
903.
A deterministic, validated, one-dimensional, unsteady-state lake water quality model was linked to a daily weather data base to simulate daily water temperature profiles in lakes over a period of twenty-five (1955–79) years. Twenty seven classes of lakes which are characteristic for the north-central U.S. were investigated. Output from a global climate model (GISS) was used to modify the weather data base to account for a doubling of atmospheric CO2. The simulations predict that, after climate change, epilimnetic temperatures will be higher but increase less than air temperature, hypolimnetic temperatures in seasonally stratified dimictic lakes will be largely unchanged or even lower than at present, evaporative water loss will be increased by as much as 300 mm for the season, onset of stratification will occur earlier and overturn later in the season, and overall lake stability will become greater in spring and summer. 相似文献
904.
Carbon leakage is central to the discussion on how to mitigate climate change. The current carbon leakage literature focuses largely on industrial production, and less attention has been given to carbon leakage from the electricity sector (the largest source of carbon emissions in China). Moreover, very few studies have examined in detail electricity regulation in the Chinese national emissions trading system (which leads, for example, to double counting) or addressed its implications for potential linkage between the EU and Chinese emissions trading systems (ETSs). This article seeks to fill this gap by analysing the problem of ‘carbon leakage’ from the electricity sector under the China ETS. Specifically, a Law & Economics approach is applied to scrutinize legal documents on electricity/carbon regulation and examine the economic incentive structures of stakeholders in the inter-/intra-regional electricity markets. Two forms of ‘electricity carbon leakage’ are identified and further supported by legal evidence and practical cases. Moreover, the article assesses the environmental and economic implications for the EU of potential linkage between the world’s two largest ETSs. In response, policy suggestions are proposed to address electricity carbon leakage, differentiating leakage according to its sources.
Key policy insights
Electricity carbon leakage in China remains a serious issue that has yet to receive sufficient attention.
Such leakage arises from the current electricity/carbon regulatory framework in China and jeopardizes mitigation efforts.
With the US retreat on climate efforts, evidence suggests that EU officials are looking to China and expect an expanded carbon market to reinforce EU global climate leadership.
Given that the Chinese ETS will be twice the size of the EU ETS, a small amount of carbon leakage in China could have significant repercussions. Electricity carbon leakage should thus be considered in any future EU–China linking negotiations.
905.
Jasim?Al-KhalidiEmail author Mihai?Dima Sabina?Stefan 《Theoretical and Applied Climatology》2018,133(1-2):179-190
The impact of large-scale modes on Iraq climate is investigated here based on winter and spring fields of temperature and precipitation. The temperature data (1971–2010) was recorded at 8 stations whereas the precipitation fields (1981–2010) were recorded at 18 locations. Empirical orthogonal function analyses were performed in order to characterize the spatial variability of the Iraq climatological parameters. The relationships between the global sea surface temperature, sea level pressure, and geopotential height fields with the dominant modes of Iraq temperature and precipitation were also investigated. Correlation and regression maps emphasize links between Iraq climate and large-scale modes, like the Atlantic Multidecadal Oscillation and the El Niño Southern Oscillation phenomenon. 相似文献
906.
Octoradiate Spiral Organisms in the Ediacaran of South China 总被引:11,自引:0,他引:11
TANG Feng YIN Chongyu Stefan Bengtson LIU Pengju WANG Ziqiang GAO Linzhi 《《地质学报》英文版》2008,82(1):27-34
Shales of the Ediacaran Doushantuo Formation of South China contain a new disc-shaped macrofossil, Eoandromeda octobrachiata, characterized by eight spiral arms that were probably housed within an outer membrane. Although the presence of eight radiating structures entails a resemblance to cnidarian octocorals as well as to ctenophores, direct homologies with these extant groups are unlikely. Instead we bring attention to the helicospiral morphology of newly reported embryos from the Doushantuo Formation, suggesting that the long-sought adults of the Ediacaran embryonic metazoans have finally been found. 相似文献
907.
908.
CODE’s five-system orbit and clock solution—the challenges of multi-GNSS data analysis 总被引:1,自引:1,他引:0
Lars Prange Etienne Orliac Rolf Dach Daniel Arnold Gerhard Beutler Stefan Schaer Adrian Jäggi 《Journal of Geodesy》2017,91(4):345-360
This article describes the processing strategy and the validation results of CODE’s MGEX (COM) orbit and satellite clock solution, including the satellite systems GPS, GLONASS, Galileo, BeiDou, and QZSS. The validation with orbit misclosures and SLR residuals shows that the orbits of the new systems Galileo, BeiDou, and QZSS are affected by modelling deficiencies with impact on the orbit scale (e.g., antenna calibration, Earth albedo, and transmitter antenna thrust). Another weakness is the attitude and solar radiation pressure (SRP) modelling of satellites moving in the orbit normal mode—which is not yet correctly considered in the COM solution. Due to these issues, we consider the current state COM solution as preliminary. We, however, use the long-time series of COM products for identifying the challenges and for the assessment of model-improvements. The latter is demonstrated on the example of the solar radiation pressure (SRP) model, which has been replaced by a more generalized model. The SLR validation shows that the new SRP model significantly improves the orbit determination of Galileo and QZSS satellites at times when the satellite’s attitude is maintained by yaw-steering. The impact of this orbit improvement is also visible in the estimated satellite clocks—demonstrating the potential use of the new generation satellite clocks for orbit validation. Finally, we point out further challenges and open issues affecting multi-GNSS data processing that deserves dedicated studies. 相似文献
909.
Zieger Stefan Greenslade Diana J. M. Aijaz Saima Kepert Jeffrey D. Burton Andrew 《Ocean Dynamics》2021,71(5):559-588
Ocean Dynamics - This paper describes a series of hindcast simulations of 17 tropical cyclones over the northwest shelf region of Australia. Tropical cyclone track and vortex details were obtained... 相似文献
910.
Harald Milsch Ronny Giese Mathias Poser Stefan Kranz Elvira Feldbusch Simona Regenspurg 《Environmental Earth Sciences》2013,70(8):3459-3463
A versatile fluid–chemical monitoring unit has been developed in the framework of the geothermal research platform Groß Schönebeck, Germany. It enables selective online and in situ measurements of various physico-chemical parameters at different surface locations of a geothermal fluid loop. Sensors are provided for pressure, temperature, volumetric flow rate, density, pH-value, redox potential, oxygen content, and electrical conductivity. In addition, the apparatus features two fluid samplers to manually collect fluid under in situ conditions and ultimately analyze the solution composition. All devices are mounted on a rack allowing easy transfer of the apparatus to other geothermal plants. The maximum operating pressure and temperature of the unit are 15 bar and 150 °C, respectively. The scientific and technical purpose of the system is to monitor a compositional variability of the produced fluid and chemical processes potentially occurring within the plant. These may result from reactions between the fluid and the surrounding materials, e.g., corrosion. Also, mineral precipitation as a consequence of temperature and/or pressure decrease or oxygen contamination may occur. This information is of paramount importance as so induced reactions might lead to failure of plant components or may damage the geothermal reservoir upon fluid reinjection and thus decrease injectivity. 相似文献