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1.
David P. Bacon Nash’at N. Ahmad Thomas J. Dunn Michael C. Monteith Ananthakrishna Sarma 《Natural Hazards》2008,44(3):317-327
By definition, a crisis is a situation that requires assistance to be managed. Hence, response to a crisis involves the merging
of local and non-local emergency response personnel. In this situation, it is critical that each participant: (1) know the
roles and responsibilities of each of the other participants; (2) know the capabilities of each of the participants; and (3)
have a common basis for action. For many types of natural disasters, this entails having a common operational picture of the unfolding events, including detailed information on the weather, both current and forecasted, that may impact on either
the emergency itself or on response activities. The Consequences Assessment Tool Set (CATS) is a comprehensive package of
hazard prediction models and casualty and damage assessment tools that provides a linkage between a modeled or observed effect
and the attendant consequences for populations, infrastructure, and resources, and, hence, provides the common operational
picture for emergency response. The Operational Multiscale Environment model with Grid Adaptivity (OMEGA) is an atmospheric
simulation system that links the latest methods in computational fluid dynamics and high-resolution gridding technologies
with numerical weather prediction to provide specific weather analysis and forecast capability that can be merged into the
geographic information system framework of CATS. This paper documents the problem of emergency response as an end-to-end system
and presents the integrated CATS–OMEGA system as a prototype of such a system that has been used successfully in a number
of different situations. 相似文献
2.
Penetration of a layer of fibre by wind reduces its effectiveness as a barrier to heat flow. In the literature, the dependence of coat or clothing insulation I(u) on windspeed u is usually described by a relation of the form I(u) = I(0) – au
1/2, where a is a constant. Re-analysis reveals that it is more appropriate to treat coat conductance (proportional to 1/I) as a linear function of windspeed. Vapour conductance can also be treated as a linear function of windspeed.On leave from Washington State University, Department of Agronomy and Soils. 相似文献
3.
The evaporitic Hessian Zechstein Basin is a sub‐basin of the Southern Zechstein Basin, situated at its southern margin. Twelve facies groups were identified in the Zechstein Limestone and Lower Werra Anhydrite in order to better understand the sequence‐stratigraphic evolution of this sub‐basin, which contains economically important potassium salts. Four different paleogeographic depositional areas were recognized based on the regional distribution of facies. Siliciclastic‐carbonate, carbonate, carbonate‐evaporite and evaporite shallowing‐upward successions are developed. These allow the establishment of parasequences and sequences, as well as correlation throughout the Hessian Basin and into the Southern Zechstein Basin. Two depositional sequences are distinguished, Zechstein sequence 1 and Zechstein sequence 2. The former comprises the succession from the Variscan basement up to the lowermost part of the Werra Anhydrite, including the Kupferschiefer as part of the transgressive systems tract. The highstand systems tract is defined by the Zechstein Limestone, in which two parasequences are developed. In large parts of the Hessian Basin, Zechstein sequence 1 is capped by a karstic, subaerial exposure surface, interpreted as recording a type‐1 sequence boundary that formed during a distinct brine level fall. Low‐lying central areas (Central Hessian Sub‐basin, Werra Sub‐basin), however, were not exposed and show a correlative conformity. Topography was minimal at the end of sequence 1. Widely developed perilittoral, sabkha and salina shallowing‐upward successions indicate a renewed rise of brine level (interpreted as a transgressive systems tract), because of inflow of preconcentrated brines from the Southern Zechstein Basin to the north. This marks the initiation of Zechstein sequence 2, which comprises most of the Lower Werra Anhydrite. In the Central Hessian Sub‐basin, situated proximal to the brine inflow and on the ridges within the Hessian Basin, physico‐chemical conditions were well suited for sulphate precipitation to form a thick cyclic succession. It consists of four parasequences that completely filled the increased accommodation space. In contrast, only minor sulphate accumulation occurred in the Werra Sub‐basin, situated further southwards and distal to the inflow. As a result of substantially different sulphate precipitation rates during increased accommodation, water depth in the region became more variable. The Werra Sub‐basin, characterized by very low sedimentation rates, became increasingly deeper through time, trapping dense halite brines and precipitating rock salt deposits (Werra Halite). This ‘self‐organization’ model for an evaporitic basin, in which depositional relief evolves with sedimentation and relief is filled by evaporite thereafter, contradicts earlier interpretations, that call upon the existence of a tectonic depression in the Werra area, which controlled sedimentation from the beginning of the Zechstein. 相似文献
4.
Resistance of a partially wet canopy: Whose equation fails? 总被引：2，自引：0，他引：2
J. L. Monteith 《Boundary-Layer Meteorology》1977,12(3):379-383
Shuttleworth's analysis of evaporation from partly wet canopies is appropriate only for the unrealistic case of dispersed, minute water droplets. When a more realistic model is used, the predicted range of canopy resistances is consistent with experimental estimates for a pine forest. 相似文献
5.
6.
S. S. Monteith J. M. Buttle P. W. Hazlett F. D. Beall R. G. Semkin D. S. Jeffries 《水文研究》2006,20(5):1095-1116
Impacts of forest harvesting on groundwater properties, water flowpaths and streamflow response were examined 4 years after the harvest using a paired‐basin approach during the 2001 snowmelt in a northern hardwood landscape in central Ontario. The ability of two metrics of basin topography (Beven and Kirkby's ln(a/tan β) topographic index (TI) and distance to stream channel) to explain intra‐basin variations in groundwater dynamics was also evaluated. Significant relationships between TI and depth to potentiometric surface for shallow groundwater emerged, although the occurrence of these relationships during the melt differed between harvested and control basins, possibly as a result of interbasin differences in upslope area contributing to piezometers used to monitor groundwater behaviour. Transmissivity feedback (rapid streamflow increases as the water table approaches the soil surface) governed streamflow generation in both basins, and the mean threshold depths at which rapid streamflow increases corresponded to small rises in water level were similar for harvested (0·41 ± 0·05 m) and forested (0·38 ± 0·04 m) basins. However, topographic properties provided inconsistent explanations of spatial variations in the relationship between streamflow and depth to water at a given piezometer for both basins. Streamflow from the harvested basin exceeded that from the forested basin during the 2001 melt, and hydrometric and geochemical tracer results indicated greater runoff from the harvested basin via surface and near‐surface pathways. These differences are not solely attributable to harvesting, since the difference in spring runoff from the harvested basin relative to the forested control was not consistently larger than under pre‐harvest conditions. Nevertheless, greater melt rates following harvesting appear to have increased the proportion of water delivery to the stream channel via surface and near‐surface pathways. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
7.
Daily mean values of the Priestley-Taylor coefficient, ¯, are derived from a simple model of the daily growth of a convective boundary layer. For a particular control set of driving environmental variables, ¯ is related to the prescribed bulk surface resistance, rS by 1/¯ = 1/0 + mrS for parameters 0 and m. The dependence of the parameters 0 and m on weather is explored and a potential use of this linear relation to provide information about regional values of rS is indicated. 相似文献
8.
R. J. Flower D. T. Monteith A. W. Mackay J. M. Chambers P. G. Appleby 《Journal of Paleolimnology》1995,14(2):101-111
The Baikal sediment box corer represents an innovation in design of the closing mechanism and involves a single, thin, and flexible stainless steel blade rather than closing jaws. With this light-weight box corer only a relatively small cross-sectional area is offered to the sediment, allowing easier penetration. The closure blade is propelled smoothly across the base of the box in a downwardly convex path by a set of constant force springs. Depending on choice of blade-release mechanisms, the corer can either be triggered immediately as the support cable slackens, after a delay of a few seconds, or immediately upon retrieval. The box corer has been used successfully to sample poorly consolidated sediments in freshwater lakes over a depth range of 8 to 1624 m. Cores of deep-water surficial sediment from Lake Baikal were tested for representativity and replicability by profiling natural and artificial radioisotopes and lithostratigraphic features. 相似文献
9.
The Cawthron Institute Culture Collection of Micro-algae (CICCM) is a unique, nationally and internationally significant collection of 450 strains of approximately 100 micro-algae and 50 cyanobacteria species, both living and cryopreserved. The collection comprises 13 taxonomic classes and underpins research into the ecology and taxonomy of the isolates and the biotoxins they produce and their toxicity. The CICCM expanded significantly in the 1990s after a major harmful algae bloom event in the Hauraki Gulf, New Zealand. Since 2000, it has underpinned development of molecular detection tools and enabled development of new chemical testing methods for biotoxins in seafood. The tropical collection allows research into potential issues for New Zealand as the oceans warm, for example, the risks of ciguatera fish poisoning and palytoxins in seafood. Research results generated from isolates in the cyanobacterial collection have assisted national risk management regarding drinking water and informed the development of the New Zealand guidelines for managing cyanobacteria in recreational fresh waters. The actual living and cryopreserved micro-algae and cyanobacteria collection (without infrastructure) has a current estimated value of NZ$1.6 million. 相似文献
10.
Summary Simple thermopiles formed by copper-plating a constantan wire were used to build a solarimeter and a net radiometer. Output was 5–10 mV per cal·cm–2·min–1, adequate to operate a small portable galvanometer for spot readings, a continuously recording potentiometer, or, for integration, a Siemens electrolytic meter. The net radiometer was unventilated, but when oscillated manually, output was independent of wind speed. With two solarimeters in a null-balance circuit, reflection and transmission coefficients of a field crop were read directly on a dial. A circuit was designed to integrate solarimeter output and the standard error of weekly readings was only ±40 cal·cm–2.
With 8 Figures 相似文献
Zusammenfassung Einfache, durch Verkupferung eines Konstantandrahts gebildete Thermosäulen wurden zum Bau eines Solarimeters und eines Strahlungsbilanzmessers verwendet. Die Thermospannung betrug 5–10 mV per cal·cm–2·min–1, was für Einzelablesungen an einem kleinen transportablen Galvanometer, für fortlaufende Registrierung mit einem Potentiometer und für Integration mit einem Elektrolytzähler von Siemens ausreichend ist. Der Bilanzmesser war nicht ventiliert; doch konnte die Anzeige durch Hin- und Herbewegen des Empfängers von der Windgeschwindigkeit unabhängig gemacht werden. Mit Hilfe von zwei kombinierten Solarimetern konnten Reflexions- und Transmissionskoeffizienten einer Pflanzung direkt abgelesen werden. Es wurde eine Schaltung zur Integration der Solarimeteranzeigen entwickelt, bei der der mittlere Fehler der Wochensummen nur ±40 cal cm–2 betrug.
Résumé L'auteur se sert de couples thermo-éléctriques faits de fils de constantan plaqués de cuivre pour construire un solarimètre et un appareil pour la mesure du bilan de radiation. La tension ainsi développée est de 5 à 10 mV par cal·cm–2·min–1. Ceci suffit aussi bien pour des lectures à un galvanomètre transportable, que pour l'enregistrement au moyen d'un potentiomètre ou pour l'intégration par un compteur électrolytique Siemens. Le bilanmètre n'était pas ventilé, mais on a aisément pu supprimer l'influence de la vitesse du vent en l'agitant de la main. Au moyen de la combinaison de deux solarimètres, on peut établir directement les coefficients de réflexion et de transmission d'une culture. On a enfin construit un circuit permettant d'intégrer les indications du solarimètre, circuit dont l'erreur moyenne de la somme hebdomadaire n'est que de ±40cal·cm–2.
With 8 Figures 相似文献