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Trevor J McDougall Rainer Feistel 《Deep Sea Research Part I: Oceanographic Research Papers》2003,50(12):1523-1535
The adiabatic lapse rate is commonly explained as being proportional to the work done on a fluid parcel as its volume changes in response to an increase in pressure. According to this explanation the adiabatic lapse rate would increase with both pressure and the fluid's compressibility, but this is not the case. Rather, the adiabatic lapse rate is proportional to the thermal expansion coefficient and is independent of the fluid's compressibility. Here we show that the adiabatic lapse rate is independent of the increase in the internal energy that a parcel experiences when it is compressed. We explain what is missing from the traditional explanation of the adiabatic lapse rate and we explore the thermodynamic cause of the adiabatic lapse rate. In particular, we seek to explain how the adiabatic lapse rate can be negative in cool fresh water. 相似文献
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Trevor Barnes 《Geoforum》2008,39(6):1807-1810
A response to Johnston et al.’s criticisms of my earlier paper about the Cold War and geography’s quantitative revolution that I am overly deterministic and fail to prove my case. 相似文献
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An evaluation of trace metal distribution, enrichment factors and risk in sediments of a coastal lagoon (Ria de Aveiro, Portugal) 总被引:1,自引:1,他引:0
M. Ramiro Pastorinho Trevor C. Telfer António J. A. Nogueira Amadeu M. V. M. Soares James F. Ranville 《Environmental Earth Sciences》2012,67(7):2043-2052
This paper describes a sediment survey undertaken to unravel patterns of distribution and dispersion of trace metals in an Iberian Peninsula northwestern coastal lagoon (Ria de Aveiro). Cadmium, lead, chromium, copper and zinc were analyzed in bottom sediments. Geochemical normalization is performed and two different regression models for each metal versus aluminum are tested and compared using the respective enrichment factors (EF), an estimation of the relative importance of anthropogenic contributions to the studied sediments. Mean sediment quality guideline quotients (mSQGQ) are used to evaluate sediment quality and associated potential risk to biota with effects range low as empirical sediment quality guideline (SQG) in the basis for mSQGQ calculation. Additionally, the geoaccumulation index is calculated to compare studied sediment levels to global baseline levels. The application of SQGs revealed insufficient characterization capability, especially when contrasted to EF calculated from the regression methods. These pointed a mildly enriched system with localized ??hot spot?? areas. Therefore, it can be considered that bottom sediments in the Ria de Aveiro system are in their majority unpolluted, zinc being the only metal of concern, presenting enrichment in all four main channels. The major rivers outlets (Caster, Antu?, and Vouga) constitute point sources, thus presenting potential risk for biota. Yet, the strong tidal influence creates a damping effect by efficiently redistributing sediment bound metals. 相似文献
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Trevor D. Ford 《Geology Today》2002,18(3):100-107
Among the late 18th-century pioneers of geological science was John Whitehurst. He set the scene for the early Derbyshire geologists, White Watson and John Farey, whose books were not published until 1811, long after Whitehurst's death. But Whitehurst's ideas went beyond Derbyshire; he looked at the global situation in his book An Inquiry into the Original State & Formation of the Earth (1778, 1786). Whitehurst was a founder member of the influential Lunar Society and a close friend of many philosophers of the period. 相似文献