Transfer across the earth's surface and through the air above

Abstract

A new-comer to the subject of meteorology, browsing over its literature, particularly its dynamical and thermodynamical literature, might be excused for forming the opinion that the theoretical meteorologist was hoping to account for the evolution of the atmosphere in terms of adiabatic transformation of a frictionless system. Perhaps the meteorologist is able to make substantial progress in his study within these constricting limits. Certainly the less complex system is worthy of study before the more complex. But we all, of course, know that we should have no weather to study and that we should not be here to study anything if the atmosphere had no heat sources or sinks and were devoid of friction.The signs are in fact appearing that even in those fields where the adiabatic assumption has proved least restricting, as in the dynamical study of large-scale systems, models must begin to be more realistic thermodynamically, and to possess friction. Old problems, such as the general circulation, in which heat and momentum transfer are at the heart of the matter, are also now being treated afresh. I thought therefore that it would be opportune to consider the problem of the transfer of heat, momentum and matter in the atmosphere. I shall restrict myself to transfer in the vertical but even this problem is too large to be adequately discussed in the time available and I must ask your indulgence if I deal only with some aspects which have particularly interested me or about which I feel able to say something to the point. I shall start at the earth's surface but I hope to climb well into the atmosphere before I stop. My attitude will be unashamedly practical. The theory of transfer processes in the atmosphere is in the most rudimentary state, far more so than for example the dynamical theory of large-scale motions (themselves a part of the transfer problem), and were I to confine myself to well-argued theory I should have little to say. But I believe there is now a substantial body of knowledge on transfer which can be expressed in terms consistent with such theory as we possess, well tried in experience and therefore applicable. Man did not wait to fly until he had created a theory of flight, but, by flying encouraged the development of theory, with consequent feedback. Meteorology is a more difficult study than aeronautics but we too can try our wings and expect similar results. TRANSFER AT THE EARTH'S SURFACE

A model for computing small-scale wind variations over a water surface

“…Equation (12) is substituted in Equations (14) and ( 15) and the latter two equations are solved iteratively for the initial (Y and V. Smith and Banke (1975), Deacon (1962) and Sheppard (1958) have, among others, shown that the drag coefficient over water appears to increase with wind speed. The following formula is used here over water (approximately the average of Deacon's and Sheppard's, with V replaced by 0.7 V,):…”

On the Growth of the Spectrum of a Wind Generated Sea According to a Modified Miles-Phillips Mechanism

“…D In this study, the drag coefficient obtained by - Sheppard (1958) was used. where U 1 0 is the wind speed in meters per second at 10 w.…”

A Heat-Balance Study on Sørbreen, Jan Mayen

“…Utilizing two expressions given by Sheppard (1958), the latent and sensible heat transfers to the surface may be written as…”