Accession Number : ADA268598


Title :   A Surface Energy Budget Model Modifying Heat Flow by Foliage Effects


Descriptive Note : Final rept.


Corporate Author : ARMY RESEARCH LAB WHITE SANDS MISSILE RANGE NM


Personal Author(s) : Tofsted, David H


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a268598.pdf


Report Date : Jul 1993


Pagination or Media Count : 88


Abstract : Propagation of energy (either acoustic or electromagnetic energy) through the region of the atmosphere close to the earth's surface depends on estimates of the vertical structure of wind, pressure, temperature, humidity, and refractive index near the earth's surface. To help predict these vertical structures, the TGRAD model has been developed. The model is based on flux- profile methods, requiring simple meteorological inputs as functions of time. The model's original purpose was to predict the vertical temperature gradient profile, hence the name TGRAD. The TGRAD model has been compared against a predecessor model (the Deardorff model) and has proven to characterize the near- surface atmosphere much better under foliated conditions. It characterizes the daytime atmosphere well under all conditions studied. It characterizes the nocturnal atmosphere well until the critical Richardson number is reached. For stronger nocturnal inversions an approach is discussed that may be capable of treating these conditions. The principal improvement provided by this model is the development of sensible and latent heat flux equations that more accurately account for a surface layer partially covered by foliage.... Boundary layer, Surface energy, Budget, Foliage sensible heat


Descriptors :   *MODELS , *BUDGETS , *HEAT FLUX , *SURFACE ENERGY , *FOLIAGE , PROPAGATION , LAYERS , ELECTROMAGNETIC PROPERTIES , ENERGY , STRUCTURES , WIND , REFRACTIVE INDEX , BOUNDARY LAYER , ESTIMATES , PROFILES , TEMPERATURE GRADIENTS , LATENT HEAT , VERTICAL ORIENTATION , PRESSURE , METEOROLOGY , DAY , RICHARDSON NUMBER , HUMIDITY , ATMOSPHERES , EARTH(PLANET) , ACOUSTICS , INVERSION


Subject Categories : Meteorology
      Acoustics
      Electricity and Magnetism
      Thermodynamics


Distribution Statement : APPROVED FOR PUBLIC RELEASE