Deposition Velocity-
Deposition velocity in atmospheric chemistry: The ratio of flux density of a substance at a sink surface to its concentration in the atmosphere. While the units of this ratio are clearly those of velocity, the ratio is not a flow velocity in the normal sense of the word.
Delta Eddington-
An approximate technique for handling the complexity of shortwave radiative transfer in anisotropically scattering atmospheres. The approximate is fairly accurate for transmitted and reflected irradiance provided the optical depth of the medium is greater than radiation computations in cloudy atmospheres.
Drag Coefficients-
A dimensionless ratio of the component of force parallel to the direction of flow (drag) exerted on a body by a fluid to the kinetic energy of the fluid multiplied by a characteristic surface area of the body.
Dynamic Initialization-
A procedure that adjusts the initial conditions of and NWP (numerical weather prediction) model so that unwanted high-frequency oscillations are removed. The procedure requires that the NWP model be integrated forward and backward around the initial time using a heavily damped finite-difference equation.
