WMOD00399

• Title: WMO Training Workshop on Weather Modification for Meteorologists - Lecture Notes
• Date: 12/1/1979
• Weather Modification - Doc Type: Report

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2.4 Overall, the use of satellite data in support of weather modification is increasing
at a rapid rate. As the satel I ite techniques and analysis methods continue to improve much
of the research of yesterday is now able to be transferred to the operational: sector.
Beginning in 1979 al I possible PEP sites are being covered with high resolution (time and
space) satel I ite data. In addition, a sufficient archive of quantitative sa~el I ite data
are avai lable for cl imatology studies over nearly al I areas. i

2.5 At present the hardware and software capabi lities to efficiently carryout major'
design and evaluation studies are limited to a few research groups. However" natural
collaboration and training activities wi I I result in broader based capabi I ity, in the years
to come. As noted above, the technology transfer from research to operations is presently
moving very wel I.

3. THE SATELLITE OBSERVING SYSTEMS

3.1 Perhaps a bit more than radar, because of the diversity of satel I ite instruments.
appl ication of satell ite data requires the user to master basic fundamentals and provides
a large body of knowledge for the attention of the aspiring special ist. To meet these
needs universities and government groups have already establ ished courses and training
programs. The WMO is presently considering more satell ite training activity.

3.2 The scope of the present paper cannot repl icate such detai led traini'ng courses.
It will note the present satellite systems and suggest an approach to the mo~e detailed
training for weather modification appl ication.

3.3 Figure I shows four-fifths of the WWW geostationary satel I ite netwo~k now a key
part of the 1979 Global Weather Experiment. The fifth satel I ite to cover the Indian Ocean
sector is presently a US SMS/GOES on temporary assignment. Figure 2 is the averal I
METEOSAT mission with its many capabi I ities. In addition to images from the :satel lites,
their ability to serve as communication platforms to collect data from remote sites and
to transmit weather charts (WEFAX) are important aspects for weather modification appl ica-
tions. At Colorado State University, research in combining the sate I I ite imagery and Data
Collection Platform (DCP) data is underway.

3.4 Figure 3 displays the METEOSAT radiometer as shown in the User's Gui:de avai lable
from the European Space Agency. This instrument and its satel I ite are typical of the
present type fly i ng in geostati onary orb it. Its pr i mary measu rements are in 'the vis i b Ie
and the I I ~m infrared window regions. From a 40,000 KM orbit the effective Iground resolu-
tion is 2.5 KM in the visible and 5 KM in the infrared. A special third channel measures
upper tropospheric water vapor by use of 6.7 ~m infrared date.

3.5 Channel spectral response, atmospheric transmission effects, the me~surement of
clouds at these wavelengths, as wel I as time and space sampl ing strategies arie important
data presented in the User Guide and in training courses. Regarding the latter, the
normal time sampl ing (or time between successive images) is 30 MIN. This ca~ often be
shortened by special request for experiment coverage.

3.6 The nearl y polar orbiting satel I ites such as the METEOR and NOAA sy~tems also
provide images of high resolution as wel I as temperature and moisture soundi~g data. The
WMO has a ser.ies of information reports avai lable about these satell ites and ,their data.
See Hil Iger a~d Vonder Haar [1977.1979] for examples of use of .the sounding data at the
mesoscale.

3.7 Satel I ite display and analysis apparatus is a research area in itselif. Products
range from photofacsimi Ie devices to produce a hardcopy image, through CRT arid laser devices
for images. to man-interactive computer systems which display, mix and analyze quantitative
satell ite images, soundings and data collected from ground platforms. These1later devices
are of the CSU ADVISAR types (see Figure 4~next sections of this paper and ANNEX A to it).
Fortunately, research on field versions of the ADVISAR is now underway and the PEP should
benefit from it.