the simplicity of the proposed model is partially obscured. 
5. CONCLUDING REMARKS 
The radiative field in the atmosphere, considered as an absorbing and 
emitting medium, is determined. Being the radiative phenomena mainly restricted 
to the troposphere, the atmosphere is modelled by assuming the volumetric absor- 
ption coefficient and the temperature to depend on altitude exponentially and 
linearly, respectively. The model is so described by four parameters : two of 
them can be easily measured at ground level, the other ones can be obtained by 
using real or estimated meteorological data. A preliminary statistical control 
of the exponential law hypothesis on the basis of real meteorological data 
seems to prove a good adequacy of the proposed model. Some deviations which 
occur in the first two kilometers of the atmosphere are due to local perturba- 
tions of the thermodynamic parameters, that cannot be taken into account by the 
present simplified model. An improvement of accuracy can be obtained by simply 
applying the method twice to two distinct layers of the troposphere, but this 
procedure partially obscures the simplicity of the proposed method. 
REFERENCES 
1.- LEE S.S. et al. :"Remote Sensing Applied to Thermal Pollution" - Remote 
Sensing, 303-334, 1975 
2.- VETRELLA S. et al. :"Spectral, Morphological and Textural Data Integration 
for Remote Sensing Applications" - 14th Congr. Int. Soc. Photogr., Hambura 
1980 
3.- PRABHAKARA C. et al. :"Estimation of Sea Surface Temperature from Remote 
Sensing in the 11-to-13 um Window Region" - Journ. Geoph. Res. 20, 5039- 
5044, 1974 
4.- BECKER F. et al. :"Measurement and Mapping of the Absolute Surface Tempera- 
ture of Water Surfaces by Remote Sensing" - XII Int. Conf. Remote Sensing, 
Ann Arbor, 1979 
5.- BERARDI.P.G., VANOLI, R. :"The Radiative Field in Solar Ponds" - II Int. 
Symp. Energie non Convenzionali, Int. Centre Theor. Physics, Trieste,1981 
6.- NIEUWENHUIS G.J.A. :"Influence of the Atmosphere on Thermal Infrared Radia- 
tion" - Tellus New Letter, 14, 1980. 
334 
INFL 
SUR 
RESU 
étud 
logi 
des 
indi 
rais: 
préc 
—-"COI 
un 
= Col 
pei 
infli 
des [ 
est € 
ABSTI 
situe 
ciolc 
ring 
know 
follc