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Samanthi W. Durage Lina Kattan S. C. Wirasinghe Janaka Y. Ruwanpura 《Natural Hazards》2014,71(3):1495-1517
With increasing concerns over the possibility of tornadoes in highly populated areas in Canada, emergency managers are looking into ways to mitigate the impacts of tornadoes. Given that tornadoes can cause enormous destruction, early warnings and proper evacuation actions are critically important in helping save lives. In this paper, a survey was conducted to analyse the evacuation behaviour of households and drivers during a hypothetical tornado warning situation in the city of Calgary, Alberta. Nearly 500 Calgarians took part in the online survey and provided information on how they would respond to tornado warnings after receiving them. This paper presents the results of the survey. Using probit models, the factors influencing these evacuation decisions are identified and discussed in detail. The results of the household evacuation model show the importance of improving awareness about the safest locations during a tornado. It further highlights the need for targeting the population under the age of 30, who are more likely to take unsafe evacuation actions. The model for evacuation of drivers shows that several factors, such as knowing the difference between a watch and a warning, awareness of safe cover, receipt of warnings through natural environmental cues and the level of education, trigger evacuation actions in avoiding a tornado threat. 相似文献
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A combination of stable isotopes (18O and 2H) and hydrochemistry has been applied to investigate storage processes in relation to aquifer storage and recovery (ASR) of the shallow alluvial Quaternary aquifer in Damascus basin. The stored water, entirely taken from the Figeh springs during flood periods, was injected in a single well having a brackish groundwater. Water samples were collected from four observation wells drilled in the Damascus University Campus (DUC) site during a 3‐year period (2006–2008). The injectant water, which deviates in its chemical and isotopic signatures from that of the ambient groundwater, shows that the stored water plume remains within close proximity to the injection well (IW) (<≈ 100 m). Thus, only two wells (W13 and W14) located at a distance less than 80 m from the injection point were affected by this injection. The observation wells located at longer distances from the IW (≈145 m and ≈ 600 m for wells W15 and WHz, respectively) were completely unaffected by the injection. Although most of the chemical and isotopic parameters usefully reflected the mixing process that occurs between the injectant water and ambient groundwater, the stable isotope (18O) and chloride (Cl−) were the most sensitive parameters that quickly reflect this signature. Using a simple mass balance, the calculated proportion of injectant water reaching the well W13 was in the range of 50–90%. This proportion was even lower (30–55%) in the case of well W14. Although the drought event prevailing during this study did not much help to inject further amounts of water, higher than the injected volume (0·2416 M m3) and also not favourable to better evaluate the fate and subsurface hydrological processes, these findings offer encouragement to continue the ASR activities, as an alternative way for better management of water resources in this basin facing intensive problems. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Z. Kattan 《Journal of Arid Environments》1997,35(4):601-615
Waters from a network of rainfall collection covering nine meteorological stations distributed mainly in the western part of Syria have been assayed using chemical and environmental isotope techniques for a period of 5 months from Dec 1989 to Apr 1990. The chemistry of rain waters falling over the mountainous stations shows a low solute concentration (20–105 mg−1/L) compared with those falling over the coastal and anterior stations (50–210 mg−1/L). The rain waters are generally characterized by a high deuterium excess (d = 19 ‰) compared with that of typical global meteoric waters (d = 10 ‰). The estimated deuterium excess is lower than that for the eastern Mediterranean meteoric waters (d = 22 ‰). The altitude effect is shown up by a depletion of heavy stable isotopes of about −0·23 ‰ and −1·65 ‰ per 100 m elevation of δ18O and δD, respectively. The spatial distribution pattern of tritium contents shows a gradual build up with increasing distance from the Syrian coast. The weighted mean tritium content in rain waters falling over the country is estimated to amount to 9·5 tritium units (TU) during the period of observation. 相似文献
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Zuhair B. Hafi 《Journal of African Earth Sciences》1998,26(4):643-648
Chemical analyses of more than 80 water wells penetrating the first aquifer in the coastal areas east of Tripoli indicate three different hydrochemical facies. Sodium chloride type water is mainly related to the encroachment of sea water as a result of excessive abstraction. The chemical interaction between groundwater and the aquifer materials led to the formation of calcium bicarbonate type water. Calcium chloride type is developed when the intruded sea water, very rich in Na ions, forced through the aquifer materials, and part of these cations replaced the Ca at the exchange sites of the clay minerals.Plotted against chloride, the concentrations of the Na, K, Ca, Mg, sulphate and bicarbonate species deviate considerably from the ideal mixing curves of fresh groundwater and sea water. Sulphate and bicarbonate enrichments are strongly related to the oxidation of sulphides and dissolution of calcite minerals present in the aquifer materials. Sea water intrusion and reverse cation exchanges reactions are the most important phenomena in the chemical evolution of the salinised groundwater. 相似文献
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Grant M. Cox Christopher J. Lewis Alan S. Collins Galen P. Halverson Fred Jourdan John Foden David Nettle Fayek Kattan 《Gondwana Research》2012,21(2-3):341-352
The Ad Dawadimi Terrane is an Ediacaran basin of the Arabian Nubian Shield (ANS), Saudi Arabia. This basin terrane is situated in the far eastern part of the ANS and represents the youngest accretion event of the exposed ANS. Therefore, the timing of events within the basin is key to understanding both the closure of the Mozambique Ocean and the amalgamation of Gondwana along the northern East African Orogen. Here we present U/Pb detrital zircon data for the Abt Formation, the principle basin sediments of the Ad Dawadimi Terrane, along with 40Ar/39Ar ages on muscovite and whole rock Sm/Nd data. These data indicate that deep-water deposition in the Abt Basin did not end until after ca. 620 Ma and that deformation and greenschist-facies metamorphism of the Abt Formation occurred at 620 ± 3 (2σ) Ma along an active margin. This is the youngest terrane amalgamation event reported so far in the Arabian–Nubian Shield, but we suggest even younger sutures lie further east beneath the Phanerozoic cover of eastern Saudi Arabia. Our results suggest that the Ediacaran basins of the eastern ANS were not part of the Huqf basin in Oman, which was instead part of a passive margin of Neoproterozoic India, separated from the active margin of Africa by the Mozambique Ocean that probably did not close until the late Ediacaran or early Cambrian. 相似文献
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Y. Al Ali M. Hrairi I. Al Kattan 《International Journal of Environmental Science and Technology》2012,9(3):495-502
In order to reduce the level of atmospheric pollution caused by vehicle engine emissions, application of a novel technique based on fuel magnetization has been tested in this study aiming at improving fuel efficiency and reducing the rate of gas emissions into the environment. Two experiments were conducted, each using a different type of magnetic device. The first type of magnetic device is installed within the fuel tank and the second is installed onto the fuel line. Each experiment was performed on ten separate vehicles from the Dubai Taxi Corporation fleet. When compared to the baseline data, reductions of 70?% for both hydrocarbon and carbon monoxide emissions, and 68?% for oxides of nitrogen were recorded. Results also demonstrated an average fuel consumption reduction of 18?%. These results clearly indicate that the introduction of magnetic field within the fuel supply of engine enhances the combustion process, thereby economizing fuel consumption and reducing the environmentally harmful emissions. 相似文献
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Characterization of surface water and groundwater in the Damascus Ghotta basin: hydrochemical and environmental isotopes approaches 总被引：1，自引：0，他引：1
Zuhair Kattan 《Environmental Geology》2006,51(2):173-201
The hydrochemistry of major ions and environmental isotope compositions (18O, 2H and tritium) of water samples have been used to investigate the characteristics of rainfalls, surface water and groundwater in the Damascus Ghotta basin. The groundwater salinity in the Damascus Ghotta basin gradually increases, as the groundwater moves from western to south-eastern and north-eastern parts of the basin. A strong relationship exists between the Barada river and the surrounded groundwaters, mainly in terms of recharge by infiltration of surface waters. The groundwater quality in the Adra region has clearly become less saline as a result of establishment of the sewage-water-treatment station in this area since 1997. The uncommon depleted stable isotope concentrations in the vicinity of Al-Ateibeh Lake and Adra valley could be interpreted as a result of sub-flow recharge from the Cenomanian–Turonian aquifer, mostly prolonged along the Damascus Fault, which forms direct contact between this complex and the Quaternary alluvium aquifers. The extensive exploitation of water from the Cenomanian–Turonian aquifer for drinking water supply would shortly be reflected by a gradual decline of the groundwater table in the Damascus Ghotta basin. Amelioration of water quality in the Damascus basin still requires further management strategies and efforts to be taken within the forthcoming years. 相似文献
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Zuhair Kattan 《Hydrogeology Journal》2002,10(4):495-508
Groundwater from the Palaeogene aquifer system in north-eastern Syria has been studied using chemical and isotopic methods
to determine the effects of carbonate dissolution, sulphate reduction and geogenic CO2 incorporation in the dilution of 14C activity, and later to correct the conventional 14C water ages. The reason for this non-classical approach of correction is because the groundwater in this karstified and Nummulitic
carbonate aquifer occurs under confined and partly confined conditions, and is located in an area very close to deep faults
and fractures. Furthermore, the interconnection with the Upper Cretaceous formations, which commonly contain gypsum and hydrocarbons,
can facilitate the processes of sulphate reduction and geogenic CO2 incorporation, which should not be excluded. The dilution factor related to carbonate dissolution was estimated to be about
0.60–0.75. The dilution factor associated with sulphate reduction, which only depends on H2S content, was rather low (about 0.95). However, as a result of the local tectonic setting in this area, the influence of
geogenic CO2 incorporation was clearly high. The dilution factor associated with this effect ranges between 0.24–0.64. Consequently, the
corrected 14C ages are considerably reduced compared with those determined by classical models. Accordingly, the groundwater in the study
area can be divided into three main groups: (1) fresh, shallow and cold water of less than 1 ka age; (2) brackish, deep and
thermal water of rather old age (10.9–12.3 ka B.P.); and (3) an admixed groundwater of intermediate quality and age (1.9–6.7 ka B.P.).
Electronic Publication 相似文献