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The American Meteorological Society promotes the development and dissemination of information and education on the atmospheric and related oceanic and hydrologic sciences and the advancement of their professional applications. Founded in 1919, AMS has a membership of more than 14,000 professionals, ...
A method of describing the movement of trace species on the turbulent or subgrid scale. The theory relates the fluxes of the trace species to the gradient of the mean quantities via the eddy diffusivity (denoted K). See also turbulent flux.
Industry:Weather
A method of describing the movement of trace species on the turbulent or subgrid scale. The theory relates the fluxes of the trace species to the gradient of the mean quantities via the eddy diffusivity (denoted K). See also turbulent flux.
Industry:Weather
The amount of mechanical work necessary to raise the temperature of a given mass of water by 1 degree Celsius. In modern usage it is the heat capacity of water, which at room temperature is 4186 Joules kg−1.
Industry:Weather
The amount of mechanical work necessary to raise the temperature of a given mass of water by 1 degree Celsius. In modern usage it is the heat capacity of water, which at room temperature is 4186 Joules kg−1.
Industry:Weather
1. A system of coordinates by which fluid parcels are identified for all time by assigning them coordinates that do not vary with time. Examples of such coordinates are 1) the values of any properties of the fluid conserved in the motion; or 2) more generally, the positions in space of the parcels at some arbitrarily selected moment. Subsequent positions in space of the parcels are then the dependent variables, functions of time and of the Lagrangian coordinates. Few observations in meteorology are Lagrangian; this would require successive observations in time of the same air parcel. Exceptions are the constant- pressure balloon observation, which attempts to follow a parcel under the assumption that its pressure is conserved, and certain small-scale observations of diffusing particles. Compare Eulerian coordinates; see also Lagrangian equations. 2. Same as generalized coordinates.
Industry:Weather
1. A system of coordinates by which fluid parcels are identified for all time by assigning them coordinates that do not vary with time. Examples of such coordinates are 1) the values of any properties of the fluid conserved in the motion; or 2) more generally, the positions in space of the parcels at some arbitrarily selected moment. Subsequent positions in space of the parcels are then the dependent variables, functions of time and of the Lagrangian coordinates. Few observations in meteorology are Lagrangian; this would require successive observations in time of the same air parcel. Exceptions are the constant- pressure balloon observation, which attempts to follow a parcel under the assumption that its pressure is conserved, and certain small-scale observations of diffusing particles. Compare Eulerian coordinates; see also Lagrangian equations. 2. Same as generalized coordinates.
Industry:Weather
An old term for the interval of time at a particular location, between the transit (upper or lower) of the moon and the next semidiurnal high water. This varies slightly during a spring-neap tidal cycle. The interval at the times of full and new moon is called “high water full and change. ” See nonharmonic tidal analysis, cotidal hour.
Industry:Weather
Statements of the factors determining the transfer and dissipation of kinetic energy at the high wavenumber end of the spectrum of turbulence. Kolmogorov considers the large anisotropic eddies as the sources of energy, which is transferred down the size scale. At some point the eddies lose all structure; they become homogeneous and isotropic, that is, “similar. ” In this region, their energy is determined only by the rate of transfer from the larger eddies and the rate of dissipation by the smaller ones. Kolmogorov stated two similarity hypotheses:
At large Reynolds numbers the local average properties of the small- scale components of any turbulent motion are determined entirely by kinematic viscosity and average rate of dissipation per unit mass. There is an upper subrange (the inertial subrange) in this bandwidth of small eddies in which the local average properties are determined only by the rate of dissipation per unit mass. It is a consequence of these hypotheses that in the inertial subrange the energy is partitioned among the eddies in proportion to k−5/3, where k is the wavenumber.
Industry:Weather
A slow-moving, extensive cyclone that forms in subtropical latitudes during the winter season. See kona.
Industry:Weather
