CALIBRATION OF AN OCS AND A PROGRAM OF RFMOTE SENSING
FROM SATELLITES OVER THE ADRIATIC AND LIGURIAN SEA
R. Frassetto - C.N.R., Laboratorio per lo Studio della Dinamica delle
Grandi Masse - San Polo 1364, 30125 Venezia, Italy
An Italian research program is underway, in the Northern Adriatic Sea
and in the Ligurian Sea which has for objective the testing and possible
use of the techniques of remote sensing to study and monitor the quality
of the sea surface waters and their dynamics.
The synoptic images of temperature (from NOAA 5) of colour (from Nim-
bus G) and of the active and passive microwave sensors (from Seasat A) are
expected to offer an attractive tool which, supplemented by discrete sea
truth measurements and mathematical models may lead to a better understand-
ing and a more precise description of the various local and regional scale
mechanisms as well as to predictions of future local conditions in connec-
tion with weather and climate variation.
The program is planned for a 5 year development. New instruments
will be tested for sampling the ocean from the surface skin to the thermo-
cline, for determining the optical characteristics of the different mate-
rials and physical and chemical properties, and to describe the dynamics
of the local sea surface.
Algorithms are being studied starting from the existing programs, to
improve the methods for correction of atmospheric effects and for the inter-
pretation of remote sensing data over coastal waters and offshore.
A calibration exercise was conducted on 25 Sept. 1977 flying an OCS 3,
11,000 meters high on a DFVLR Falcon jet plane over the North-West coastal
area of the Adriatic Sea, from Venice to Rimini (fig. 1).
Quick-look images indicate strong gradients of reflectance in all
channels of the OCS. The data, which are of good quality, supplemented
by a set of sea-truth measurements are under evaluation, in preparation
for the test of Nimbus G data. Nimbus G in fact may be operative from
25 September 1978.
Two, of a series of cruises planned, have been conducted also in the
Ligurian Sea. During the third cruise, in September-October 1978, it is
expected to make the first actual test of NimbusG data, following the ex-
perience acquired in the calibration exercises of the OCS (Fig. 2).
