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151.
The winter land breeze (WLB) was studied in an area with complex topography on the Swedish West Coast (58°N). Methods used were mapping directions of smoke plumes, temperature soundings by tethered balloon and helicopter, three years of monitoring temperature and wind at three levels on a suspension bridge and on a mast, and meteorological observations from three stations located at different distances from the coast. To initiate the development of the WLB, the necessary temperature difference between sea and land was 5°C, but the magnitude of the difference appeared to have little influence. The direction of the typical WLB was at an oblique angle to the coast. The WLB started with a sudden wind shift as a result of frictional decoupling from the prevailing synoptic wind caused by increased stability. The flow, with a depth of about 100 m, developed within the nocturnal inversion at the level of the plateau-shaped mountains and overrode the cold air in the valleys and followed the uplifted inversion over the city of Göteborg. The different layers in the inversion were tilted toward the sea with an inclination similar to the slope of the terrain. In a layer above the WLB but also within the inversion, there was an onshore wind that might be the return flow to the WLB. [Key words: winter land breeze (WLB), decoupling, overriding, urban heat island circulation (UHIC), high latitude, Sweden.] 相似文献
152.
Xavier Tunc Isabelle Faille Thierry Gallou?t Marie Christine Cacas Pascal Havé 《Computational Geosciences》2012,16(2):277-296
In this paper, we are interested in modeling single-phase flow in a porous medium with known faults seen as interfaces. We
mainly focus on how to handle non-matching grids problems arising from rock displacement along the fault. We describe a model
that can be extended to multi-phase flow where faults are treated as interfaces. The model is validated in an academic framework
and is then extended to 3D non K-orthogonal grids, and a realistic case is presented. 相似文献
153.
Anne Marie de Grosbois 《Environmental Earth Sciences》2012,65(7):2213-2218
Events
Upcoming international events 相似文献154.
Julie Sucharovà Ivan Suchara Marie Hola Sarka Marikova Clemens Reimann Rognvald Boyd Peter Filzmoser Peter Englmaier 《Applied Geochemistry》2012
High top-/bottom-soil ratios, or high values of “enrichment factors” (EFs), are used as a proof for major anthropogenic impact on the geochemistry of the Earth surface. The idea behind calculating such ratios is that soils taken at depth or “average crust” can provide the geochemical background for the soils collected at the Earth surface. However, a soil profile is not a closed system, element exchange between the different layers, depending on and varying with the chemical properties of the different elements, and their turnover in the biosphere is the essence of soil formation. High top-/bottom-soil ratios, or EFs, may thus highlight the geochemical de-coupling of the lithosphere from the biosphere rather than contamination. This is demonstrated by using regional data from 258 soil O- and B-horizon samples collected from the Czech Republic (76,800 km2). Results show no relationship between the ratios and the magnitude of anthropogenic emissions. The visible relationship between element concentrations and sources in a map of the spatial distribution of the elements is lost when maps for the top-/bottom-soil ratio or EFs are constructed. The value of the data lies in the spatial elemental distribution, and not in ratios calculated based on misconceptions. 相似文献
155.
Warren C. Jochem Kelly Sims Edward A. Bright Marie L. Urban Amy N. Rose Phillip R. Coleman Budhendra L. Bhaduri 《Natural Hazards》2013,68(3):1325-1342
In recent years, uses of high-resolution population distribution databases are increasing steadily for environmental, socioeconomic, public health, and disaster-related research and operations. With the development of daytime population distribution, temporal resolution of such databases has been improved. However, the lack of incorporation of transitional population, namely business and leisure travelers, leaves a significant population unaccounted for within the critical infrastructure networks, such as at transportation hubs. This paper presents two general methodologies for estimating passenger populations in airport and cruise port terminals at a high temporal resolution which can be incorporated into existing population distribution models. The methodologies are geographically scalable and are based on, and demonstrate how, two different transportation hubs with disparate temporal population dynamics can be modeled utilizing publicly available databases including novel data sources of flight activity from the Internet which are updated in near-real time. The airport population estimation model shows great potential for rapid implementation for a large collection of airports on a national scale, and the results suggest reasonable accuracy in the estimated passenger traffic. By incorporating population dynamics at high temporal resolutions into population distribution models, we hope to improve the estimates of populations exposed to or at risk to disasters, thereby improving emergency planning and response, and leading to more informed policy decisions. 相似文献
156.
157.
Marie Tharp 《Marine Geodesy》2013,36(1):63-65
Mixed layer depth (MLD) is an important parameter in the study of air‐sea interaction, acoustic propagation, and fisheries. With the onset of the southwest monsoon, a jetlike surface water flow develops from west to east along the equatorial Indian Ocean (EIO) creating an upward west to east sea surface slope. This in turn creates a slope in MLD in the opposing direction. In this paper, emphasis is placed on obtaining monthly coefficients between MLD and sea level for three regions across the EIO. Using these coefficients, MLD has been estimated from Geosat altimeter data. MLD in this region has been computed with an RMS error of 16 m, from altimeter data, as verified by TOGA in situ profiles. 相似文献
158.
Alina Marie Hasbi Mohammed Awad Momani Mohd Alauddin Mohd Ali Norbahiah Misran Kazuo Shiokawa Yuichi Otsuka Kiyohumi Yumoto 《Journal of Atmospheric and Solar》2009,71(17-18):1992-2005
This paper investigates the ionospheric and geomagnetic responses during the 28 March 2005 and 14 May 2005 Sumatran earthquakes using GPS and magnetometer stations located in the near zone of the epicenters. These events occurred during low solar and geomagnetic activity. TEC oscillations with periods of 5–10 min were observed about 10–24 min after the earthquakes and have horizontal propagation velocities of 922–1259 m/s. Ionospheric disturbances were observed at GPS stations located to the northeast of the epicenters, while no significant disturbances were seen relatively east and south of the epicenters. The magnetic field measurements show rapid fluctuations of 4–5 s shortly after the earthquake, followed by a Pc5 pulsation of 4.8 min about 11 min after the event. The correlation between the ionospheric and geomagnetic responses shows a good agreement in the period and time lag of the peak disturbance arrival, i.e. about 11–13 min after the earthquake. 相似文献
159.
The stability and structure of aqueous complexes formed by trivalent antimony (SbIII) with carboxylic acids (acetic, adipic, malonic, lactic, oxalic, tartaric, and citric acid), phenols (catechol), and amino acids (glycine) having O- and N-functional groups (carboxyl, alcoholic hydroxyl, phenolic hydroxyl and amine) typical of natural organic matter, were determined at 20 and 60 °C from solubility and X-ray absorption fine structure (XAFS) spectroscopy measurements. In organic-free aqueous solutions and in the presence of acetic, adipic, malonic acids and glycine, both spectroscopic and solubility data are consistent with the dominant formation of SbIII hydroxide species, , at strongly acid, acid-to-neutral and basic pH, respectively, demonstrating negligible complexing with mono-functional organic ligands (acetic) or those having non adjacent carboxylic groups (adipic, malonic). In contrast, in the presence of poly-functional carboxylic and hydroxy-carboxylic acids and catechol, SbIII forms stable 1:1 and 1:2 complexes with the studied organic ligands over a wide pH range typical of natural waters (3 < pH < 9). XAFS spectroscopy measurements show that in these species the central SbIII atom has a distorted pseudo-trigonal pyramidal geometry composed of the lone pair of 5s2 electrons of Sb and four oxygen atoms from two adjacent functional groups of the ligand (OC-OH and/or COH), forming a five-membered bidendate chelate cycle. Stability constants for these species, generated from Sb2O3 (rhomb.) solubility experiments, were used to model Sb complexing with natural humic acids possessing the same functional groups as those investigated in this study. Our predictions show that in an aqueous solution of pH between 2 and 10, containing 1 μg/L of Sb and 5 mg/L of dissolved organic carbon (DOC), up to 35% of total dissolved Sb binds to aqueous organic matter via carboxylic and hydroxy-carboxylic groups. This amount of complexed Sb for typical natural DOC concentrations is in agreement with that estimated from dialysis experiments performed with commercial humic acid in our work and those available in the literature for a range of standardized IHSS humic acids. Our results imply that a significant part of Sb is likely to be bound with humic acids via hydroxy-carboxylic moieties, in the form of bidendate complexes. However, following the strong chemical affinity of SbIII for reduced sulfur, some undefined fraction of SbIII might also be bound to the minor thiol-bearing moieties of humic acids; further studies are required to check this hypothesis. 相似文献
160.