Inference of horizontal temperature gradients using passive radiometric methods
Date
1989-08
Authors
Olsson, Peter, author
Cox, Stephen K., author
Journal Title
Journal ISSN
Volume Title
Abstract
There exist many situations in nature where relatively strong horizontal temperature gradients are present in the boundary layer. The purpose of this work is to investigate the impact of horizontal temperature gradients on the infrared radiance properties c the boundary layer and devise a scheme for inferring the gradient magnitude from these radiance properties. The temperature and spectral dependence of the radiance of various atmospheric constituents are examined and them portion of the spectrum 500 cm-1 v 800cm-1 shown to be most sensitive to temperature induced radiance changes. The two important radiating gases at these wavenumbers are CO2 and H2O. The spectral radiative properties of these constituents are discussed. The variability of the water vapor mixing ratio is shown to be an important factor in this remote sensing application. A model is discussed which numerically estimates the radiance of the boundary layer in the presence of a horizontal temperature gradient. The results of this model demonstrate the possibility of estimation the gradient magnitude from narrow band azimuthally scanned radiance measurements Two parameters, the attenuation length and the centered normalized radiance, introduced and their relationship to the gradient magnitude is explored. Using the parameters, a method is developed which permits the inference of temperature gradient magnitude from infrared radiance measurements and local pressure, temperature and mixing ratio values. The success of this technique is demonstrated by the accurate recovery of gradient magnitudes from calculated radiance data. Finally, consideration is given sources of error and uncertainty in the measurement process and the impact of these on the inference of the gradient magnitude.
Description
August 1989.
Also issued as Peter Olsson's thesis (M.S.) -- Colorado State University, 1989.
Also issued as Peter Olsson's thesis (M.S.) -- Colorado State University, 1989.
Rights Access
Subject
Atmospheric temperature -- Measurement
Atmospheric radiation -- Measurement
Boundary layer (Meteorology)