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this wavelangth band is that low noise equivalent temperatures 
may be atteined in radiometric measuroments since the terres- 
trial emission has its peak value in this spectrzl region (1). 
Field tests of the application of the infrared radiometer 
to the measurement of water surface temperctures have indicated 
that there is a significant difference betwe-n the reading of 
the the re‘iant temperature and the measurement made by some 
contact method (1),(2),(3),(4). Furthermore this difference 
doesn't seem to be const .nt but attributable to three main al- 
te-in, sources: i) atmospheric influence on the emerging radia- 
tion intensity; ii) atmosphere-sea surface interface, and iii) 
errors when considoring the instrumont afecting factors. The 
infrared rsdiomster messures tho brightness temperature of a 
very thin surface layer of the water at the air-uster interface 
(3), When the temperature gradient of the layer is strong, the 
‘reading corresponds to an intermidiate temperature between that 
of the surface waters and that of the deeper layers. On the 
other hand, a conventional contact thermometer reads the kinetic 
temperature of a layer which is generally not coincident with 
the surface layer. The difference betucen the two measurements 
may be cf great importance if the temperature cradient in the 
upper layers of the ocaan is strong. If conditions are such as 
to increase the temperature gradient in the surface layer, then 
tne difference betuean the tuo measurements decreases as it is 
shown in figure 1. Hence that the difference depends on tne 
heat and mzss transfer processes occurring at the interface. 
The present study does not offer any improvement in this respect 
The problem of correcting atmospheric degradation and the con- 
sileration of the error of calibration are, nowever, better re- 
solved in this study. 
It is a known Fact that radiant energy determined at flight 
level differs from that measured near the surface because of the 
attznuacicn by the intservoning atm sphere itself, The indicated 
temperature at flight level is then greater that, equal to or 
less than the surfacz value according to wether the temperature 
of the atmosphere is greater than, equal to or less than the sur 
face value. SAUNDERS (4) raports that for an altitude of 300 m 
differences due only to atmospheric effects may amount to + 0,5 
SC even in the window region. Other authors (5) give an accor- 
cance of 0.39C for a flight altitude of 400 meters , Or even of 
G.59C at other altitudes (6). A literature survey of the many 
methods used Lo minimize atmospheric influenca won't be given 
here since it may be found. elseuhere (7),(8),(5). In this paper 
a method for correcting atmospheric path disturbance is included 
in the global correction. The method is based on the solution 
of the radiative transfer squation under the assumption of a 
unity-valued emissivity of sea water for the 9.5 - 11.5 p yin- 
dou region. 
Thermal discontinuities do meander and undergo distortions 
with time due to the combined offects of turbulent motions with 
in in the water body, cloudiness and wind stress on the water 
surface, Thus that the radiometer has to be calibrated account 
ing all possible factors. that may influence its temperature rea