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51.
James B. Holt Jacqueline W. Miller Timothy S. Naimi Daniel Z. Sui 《Geographical review》2006,96(4):523-542
ABSTRACT. Levels of alcohol consumption are a major public health issue. This study aims to gain a better understanding of how geographical patterns of religious affiliation in the United States relate to geographical patterns of alcohol consumption. We explored state‐level correlations between alcohol consumption and religious adherence. Although we found no statistically significant correlation between overall religious adherence rates and current or binge drinking rates, states with higher adherence rates were significantly more likely to have high proportions of binge drinking among current drinkers. Yet, regionally, we found a strong inverse correlation in the Southeast and a strong positive correlation in the Midwest and Northeast between adherence rates and current and binge drinking rates. These geographical differences were largely explained after stratifying by major religious denominational groupings. States with high Catholic adherence rates tended to have higher drinking rates, whereas states with high Evangelical Protestant adherence rates tended to have lower drinking rates. These findings suggest that the relationship between religion and alcohol may be denomination‐specific and challenge the lay perception that religious adherence per se is associated with less alcohol consumption and less excessive drinking among those who drink. 相似文献
52.
Seasonal ichthyoplankton surveys were made in the lower Laguna Madre, Texas, to compare the relative utilization of various nursery habitats (shoal grass,Halodule wrightii; manatee grass,Syringodium filiforme; and unvegetated sand bottom) for both estuarine and offshore-spawned larvae. The species composition and abundance of fish larvae were determined for each habitat type at six locations in the bay. Pushnet ichthyoplankton sampling resulted in 296 total collections, yielding 107,463 fishes representing 55 species in 24 families. A broad spectrum of both the biotic and physical habitat parameters were examined to link the dispersion and distribution of both pre-settlement and postsettlement larvae to the utilization of shallow seagrass habitats. Sample sites were grouped by cluster analysis (Ward’s minimum variance method) according to the similarity of their fish assemblages and subsequently examined with a multiple discriminant function analysis to identify important environmental variables. Abiotic environmental factors were most influential in defining groups for samples dominated by early larvae, whereas measures of seagrass complexity defined groups dominated by older larvae and juveniles. Juvenile-stage individuals showed clear habitat preference, with the more shallowHalodule wrightii being the habitat of choice, whereas early larvae of most species were widely distributed over all habitats. As a result of the recent shift of dominance fromHalodule wrightii toSyringodium filiforme, overall reductions in the quality of nursery habitat for fishes in the lower Laguna Madre are projected. 相似文献
53.
Mid-latitude ionospheric perturbation associated with the Spacelab-2 plasma depletion experiment at Millstone Hill 总被引:1,自引:0,他引:1
Elevation scans across geomagnetic mid latitudes by the incoherent scatter radar at Millstone Hill captured the ionospheric response to the firing of the Space Shuttle Challenger OMS thrusters near the peak of the F layer on July 30, 1985. Details of the excitation of airglow and the formation of an ionospheric hole during this event have been reported in an earlier paper by Mendillo et al.. The depletion (factor 2) near the 320 km Shuttle orbital altitude persisted for 35 min and then recovered to near normal levels, while at 265 km the density was reduced by a factor of 6; this significant reduction in the bottomside F-region density persisted for more than 3 hours. Total electron content in the vicinity of the hole was reduced by more than a factor of 2, and an oscillation of the F-region densities with 40-min period ensued and persisted for several hours. Plasma vertical Doppler velocity varied quasi-periodically with a 80-min period, while magnetic field variations observed on the field line through the Shuttle-burn position exhibited a similar 80-min periodicity. An interval of magnetic field variations at hydromagnetic frequencies (95 s period) accompanied the ionospheric perturbations on this field line. Radar observations revealed a downward phase progression of the 40-min period density enhancements of -1.12° km–1, corresponding to a 320-km vertical wavelength. An auroral-latitude geomagnetic disturbance began near the time of the Spacelab-2 experiment and was associated with the imposition of a strong southward IMF Bz across the magnetosphere. This created an additional complication in the interpretation of the active ionospheric experiment. It cannot be determined uniquely whether the ionospheric oscillations, which followed the Spacelab-2 experiment, were related to the active experiment or were the result of a propagating ionospheric disturbance (TID) launched by the enhanced auroral activity. The most reasonable conclusion is that the ionospheric oscillations were a result of the coincident geomagnetic disturbance. The pronounced depletion of the bottomside ionosphere, however, accentuated the oscillatory behavior during the interval following the Shuttle OMS burn. 相似文献
54.
J.T. Holt S.A. Thorpe 《Deep Sea Research Part I: Oceanographic Research Papers》1997,44(12):2087-2116
The continental slope to the south of the Celtic Sea is an area of extremely rough topography and tidal currents of the order of 50cm/s (with components both along and across the slope). This is a region of intense and complicated internal wave and internal tide activity. Historical current meter data from moorings close to the shelf-break show bursts of high frequency, large amplitude internal waves occurring, on average, at either once or twice per M2 tidal cycle. Wave packets at 9 moorings along the shelf-break and further on-shelf are identified using conditional sampling. The paths travelled by these wave packets are calculated using their fluctuation orientation, linear wave theory and the low frequency current. The records are up to 60 days long, allowing the ensemble statistics of propagation direction and wave characteristics to be calculated for a large number of wave packets. This analysis shows that only a fraction of the observed wave packets have orientations consistent with generation by the across-slope barotropic tide. This mechanism accounts for 20% of the wave packets in the north-west Celtic Sea and 29% in the southeast Celtic sea. A similar fraction of the wave packets (23% in the north west and 27% in the south east) have orientations clearly consistent with generation by an along-slope flow over the rough topography on the slope. The remaining wave packets are attributed to generation by tidal flow over topography close to the moorings and possibly internal wave resonance within canyons. 相似文献
55.
Lucy R. Wyatt J. Jim Green Andrew Middleditch Mike D. Moorhead John Howarth Martin Holt Simon Keogh 《Oceanic Engineering, IEEE Journal of》2006,31(4):819-834
This paper presents results of a trial of a Pisces HF radar system aimed at assessing its use as a component of a wave-monitoring network being installed around the coasts of England and Wales. The radar system has been operating since December 2003 and the trial continued to June 2005. The data have been processed in near-real time and displayed on a website. Radar measurements of the directional spectrum and derived parameters are compared with those measured with a directional waverider and with products from the Met Office, United Kingdom, operational wave model. Radar measurements of currents and winds are also compared with Met Office model products and, in the case of winds, with the QuikSCAT scatterometer. Statistics on data availability and accuracy are presented. The results demonstrate that useful availability and accuracy in wave and wind parameters are obtained above a waveheight threshold of 2 m and at ranges up to 120 km at the radar operating frequencies (7-10 MHz) used. Waveheight measurements above about 1 m can be made with reasonable accuracy (e.g., mean difference of 2.5% during January-February 2004). Period and direction parameters in low seas are often contaminated by noise in the radar signal. The comparisons provide some evidence of wave model limitations in offshore wind and swell conditions 相似文献
56.
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58.
A marine system model applied to the North West European shelf seas is used to simulate the consequences of distinct CO(2) additions such as those that could arise from a failure of geological sequestration schemes. The choice of leak scenario is guided by only a small number of available observations and requires several assumptions; hence the simulations reported on are engineered to be worse case scenarios. The simulations indicate that only the most extreme scenarios are capable of producing perturbations that are likely to have environmental consequences beyond the locality of a leak event. Tidally driven mixing rather than air-sea exchange is identified as the primary mechanism for dispersal of added CO(2). We show that, given the available evidence, the environmental impact of a sequestration leak is likely to be insignificant when compared to the expected impact from continued non-mitigated atmospheric CO(2) emissions and the subsequent acidification of the marine system. We also conclude that more research, including both leak simulations and assessment of ecological impacts is necessary to fully understand the impact of CO(2) additions to the marine system. 相似文献
59.
Analysis of high frequency (20 Hz) turbulence data collected from low level flights by the National Center for Atmospheric Research (NCAR) Electra aircraft over the central Arabian Sea on 20 and 24 June, 1979 as part of MONEX 79 indicates the influence of the Somali Jet on boundary-layer turbulence. Different stages of monsoon development were evident on the two observation days from mean boundary-layer profiles. However, turbulence statistics of wind speed components and temperature in the monsoon boundary layer for both days are generally greater than those observed in laboratory experiments or tropical and trade wind boundary layers in which a strong jet was not present. Analysis of high frequency wind, temperature and humidity data was made to obtain fluxes of momentum and heat. Magnitudes of the sensible and latent heat fluxes are three to five times larger than the values observed over the monsoon boundary layer over the Bay of Bengal. The turbulent kinetic energy budget over the Arabian Sea for 24 June indicates the importance of buoyancy, and to a lesser extent shear as the dominant term. Dissipation serves as the primary sink term. 相似文献
60.
Abstract A pilot project concerning the measurement of rainfall by polarization diversity radar, conducted jointly by the Alberta Research Council and the University of Essex in the summer of 1989, is described. The objective of the experiment was to test the theory that differential propagation phase shift can give a better estimate of rainfall with high rain rates (about 30 mm h?1 and greater) than reflectivity measurements. The project comprised a field experiment that was conducted in central Alberta during the period 20 July to 2 August 1989. The field experiment involved observing storms within about a 70‐km radius from Red Deer with the ARC S‐band polarization diversity radar and measuring rainfall at the ground through a network of fixed, volunteer observers and a mobile storm‐chase operation. Theory describing how differential propagation phase may be extracted from the data recorded by the radar system is given. Data collected on three days during the experiment (27 July, 29 July and 2 August) have been analysed and the results are presented. A total of 31 samples of total rainfall amount were collected on these days. All but three of the 31 radar rainfall amount predictions obtained from the differential propagation phase are within a factor of 2 of the rainfall observed at the ground. In fact, the average ratio of the total rainfall amount predicted from the differential propagation phase to the total rainfall amount measured at the ground is 1.16 for the 31 samples. This suggests that, on average, the total rainfall amount predicted from the differential propagation phase is only 16% higher than that measured at the ground. Of the 31 events, over a third involved some contamination of the differential propagation phase measurement through hail. Furthermore, because the KDP technique does not rely on parameters dependent on precipitation characteristics or adjustment factors, the technique can be validated in a convenient location and then applied anywhere. On the other hand, the radar rainfall amount estimates derived from Z‐R relations represent, in general, a large overestimation of the rainfall amount observed at the ground, especially when hail is present. No attempt was made to adjust or calibrate the radar rainfall estimates with raingauge data. 相似文献