Winds thin-film thickness

The effect of wind velocity on (a) thin-film thickness and (b) piston velocity. The solid line represents results obtained from measurements made in wind tunnels. In situ measurements were made from distributions of the naturally occurring radioisotopes of carbon and radon. Source From (a) Broecker, W. S., and T.-H. Peng (1982). Tracers in the Sea. Lamont-Doherty Geological Observatory, p. 128, and (b) Bigg, G. R. (1996). The Oceans and Climate. Cambridge University Press, p. 85. 

Implicit in this model is the assumption that molecular diffusivity and Henry s Law constant are directly and inversely proportional, respectively, to the gas flux across the atmosphere-water interface. Molecular diffusion coefficients typically range from 1 x 10-5 to 4 x 10-5 cm2 s-1 and typically increase with temperature and decreasing molecular weight (table 5.3). Other factors such as thickness of the thin layer and wind also have important effects on gas flux. For example, wind creates shear that results in a decrease in the thickness of the thin layer. The sea surface microlayer has been shown to consist of films 50-100 pm in thickness (Libes, 1992). Other work has referred to this layer as the mass boundary layer (MBL) where a similar range of film thicknesses has been... 

Let us further specialize to the case of a thin niobium film deposited on 1/2 mil Mylar. Although g of niobium has been reported as high as 8 kilo-oersteds, a more conservative estimate is to take B kilo-oersteds for this hard superconductor. This magnet would then produce 90 kilo- oersteds with a current of 3.0 amp per centimeter of length at zero power dissipation. K it is assumed that one could obtain a winding density of 1600 turns per inch of radius, the windings would have a radial thickness of 15 in. this means that the physical size of the magnet would be very reasonable. 

Similar to the widely adopted model of air-water exchange (Schwarzenbach et ah, 2003), the mass transfer from the snow pack-air interface to the bulk atmosphere is usually interpreted as occurring by molecular diffusion across a thin stagnant boundary layer film. Because the thickness of this boundary layer is unknown, some approaches (Wania, 1997 Daly and Wania, 2004) simply treat few as a constant. In particular, it is assumed that febi adopts values similar to a typical MTC for the boundary layer above soil (e.g., 0.14cms or 5mh Mackay and Stiver, 1991). In a more realistic approach, Hansen et al. (2006) allow for the influence of variable wind speed on febi, which they expressed as ... 

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