Thermal radiant exitance model performance: Soils and forests

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:10103370

Balick, L K ^[1]; Smith, J A ^[2]

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1. EG&G Energy Measurements Inc., Las Vegas, NV (United States)
2. NASA/Goddard Space Flight Center, Greenbelt, MD (United States). Lab. for Terrestrial Physics

Models of surface temperatures of two land surface types based on their energy budgets were developed to simulate the effects of environmental factors on thermal radiant exitance. The performance of these models is examined in detail. One model solves the non-linear differential equation for heat diffusion in solids using a set of submodels for surface energy budget components. The model performance is examined under three desert conditions thought to be a strong test of the submodels. The accuracy of the temperature predictions and submodels is described. The accuracy of the model is generally good but some discrepancies between some of the submodels and measurements are noted. The sensitivity of the submodels is examined and is seen to be strongly controlled by interaction and feedback among energy components that are a function of surface temperature. The second model simulates vegetation canopies with detailed effects of surface geometry on radiant transfer in the canopy. Foliage solar absorption coefficients are calculated using a radiosity approach for a three layer canopy and long wave fluxes are modeled using a view factor matrix. Sensible and latent heat transfer through the canopy are also simulated using, nearby meteorological data but heat storage in the canopy is not included. Simulations for a coniferous forest canopy are presented and the sensitivity of the model to environmental inputs is discussed.

• Research Organization: EG and G Energy Measurements, Inc., Las Vegas, NV (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC08-93NV11265
• OSTI ID: 10103370
• Report Number(s): EGG--11265-1075; CONF-9409265--1; ON: DE95003619
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140100
54 ENVIRONMENTAL SCIENCES
540240
COMPARATIVE EVALUATIONS
FORESTS
HEAT STORAGE
MATHEMATICAL MODELS
RADIANT HEAT TRANSFER
RESOURCES AND AVAILABILITY
SENSITIVITY ANALYSIS
SOILS
SURFACE ENERGY
THERMAL EFFLUENTS MONITORING AND TRANSPORT
THERMAL RADIATION