EARSeL Newsletter - EARSeL, European Association of Remote ...

EARSeL Newsletter September 2002 - Number 51
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ters on the US DMSP (Defence Meteorological
Satellite Programme) satellites up to F-
14, launched in April 1997.
In the opinion of the reviewer, the most interesting
part of the book is the final chapter,
dealing with "microwave observations
of processes in the ocean-atmosphere system".
It presents results of experiments carried
out from ships and aircraft, of the
phenomena previously dealt with. Internal
waves were studied in a cruise on the Indian
Sea (1981), with a radiometer-scatterometer
at 37 GHz (vertical polarisation) and a
radiometer at 1.7 GHz (horizontal polarisation)
operated at an angle of incidence of
75º. Another experiment was carried out
with a 37 GHz radiometer (vertical polarisation)
and a high-resolution echo-sounder
recording internal solitons in the Sea of
Japan (1981). Still other experiments were
carried out in the Atlantic Ocean (near
Long Island) in a Joint USA / Russia Internal
Wave Remote Sensing Experiment
(JUSREX, 1992) with the "aircraft laboratory
Tupolev-134" equipped with a real-aperture
radar at 13 GHz and radiometers at
1.6, 3.9, 20 and 37 GHz. Rather convincing
results are presented and commented on.
One section deals with the surface effect of
rain. Rain changes both the surface salinity
and occasionally also its temperature,
which changes the ripple structure on the
ocean surface and thereby the microwave
thermal emission. Examples show that the
effect is limited in time to an hour or so.
Ship-borne measurements (1984) with a radiometer
system at 48, 37, 34 and 20 GHz, all
vertical polarisation, and another channel at
37 GHz, horizontal polarisation, reveal the
rather surprising result that the "relic rain" is
observed at all frequencies except 20 and 37
GHz, vertical polarisation.
The author spends a few pages discussing
the reason for the observation that the effect
is seen on one frequency and not another,
only 3 GHz away – unfortunately not very
convincingly. In contrast, a so-called tropical
shower (20 mm/h) may be seen on all
frequencies and polarisations: at 34 GHz,
horizontal polarisation the brightness temperature
increases by more that 100 K.
Similarly, a frontal zone was detected by
the ship-borne radiometer / scatterometer
at 37 GHz in the Pacific Ocean (1983), revealing
strong ‘signatures’ of more than 20
K and 10 dB in one case, and about 3 dB in
another. An oceanic synoptic ring was
recorded from a radiometer on a TU-134 research
aircraft at 37 and 48 GHz, but not at
20 and 75 GHz (1990). The cyclone Warren
(1984) gave surface effects that were observed
at 48 and 34 GHz, but not on 20 and
37 GHz (all vertical polarisation). Finally,
SMM/I data (1997) revealed an interesting
signature in a 600 kilometres long area
along the continental break in the northern
part of Norwegian Sea.
In some of the cases presented, the observations
are supported by simultaneous oceanic
and meteorological data. In other cases
they are discussed in the context of oceanic
research in the area in question, often carried
out by Russian research vessels.
This interesting but specialised book is a revision
of a previously published book
(1994, in Russian) with some additions of
which the SMM/I data are worth mentioning.
The observations presented are thoroughly
discussed in an oceanic context,
referring to a great number of relevant research
papers. In fact, the extensive list of
references (over 275) is a valuable source of
information about oceanic and meteorological
research carried out in Russia, many of
which have been translated into English.
The book has some shortcomings, in that
the language is rather elaborate; at few
places sentences (apparently interpreted
from Russian) are difficult to understand
by another foreigner.
5.2 Book: study of Kara Sea, Russian
Arctic
Polar Seas Oceanography: An Integrated Case
Study of the Kara Sea. Authors: Vladimir A.
Volkov, Ola M. Johannessen, Victor E.
Borodachev, Gennadiy N. Voinov, Lasse H.
Pettersson, Leonid P. Bobylev and Alexei V.
Kouraev. May 2002. Praxis Publishing Ltd.
496 pp., including 12-page colour section.
ISBN: 3-54042-969-7. List price: 104.50 Euros.
The Kara Sea of the Russian Arctic, with its
unique oceanographic regime, is a site of