I5PR5
UNISPACE III - ISPRS/EARSeL Workshop on
“Remote Sensing for the Detection, Monitoring
and Mitigation of Natural Disasters”
2:30-5:30 pm, 22 July 1999, VIC Room B
Vienna, Austria
Traditionally, volcanoes are best monitored by using geophysical
instruments, so-called seismometers, which record the seismic
events very often associated with volcanic underground
movements. Remote sensing methods are suitable to observe the
surface processes of volcanic eruptions (CHOROWICZ, J et al
1992). These include also processes that precede a volcanic
emption: thermal remote sensing of volcanic lakes or fumarole
fields (ROTHERY, D.A. et al.1988; OPPENHEIMER, C. et al
1993; URAI, M. 1996; BANNERT, D. 1998), topographic
changes like bulging and collapse of the volcanic edifice could be
observed in optical and radar data, including interferometric data.
Gas emissions are monitored from ground stations in order to
detect changes in the gas composition, which could indicate a
change in the behaviour of a volcano. New instruments on
LANDSAT-7 and on the EO-1 polar platform to be launched at
the end of this century by NASA and NASDA will provide
thermal multispectral sensors with a foot-print of 60m X 60m
on the ground. They will be much more capable of thermal
mapping than the current thermal sensors on NO A A and other
weather satellites.
To assess tire local impact of a volcanic emption, radar and
optical sensors have been proven to be very cost-effective,
especially when combined with digital terrain models (DAAG, A.
&C. VANWESTEN 1996 ;).
Volcanic hazard prediction includes the application of the above
mentioned sensors, as well as precise digital terrain models in
order to predict possible emption centres and tire possible
distribution of volcanic products downhill.
3.4 Active faults and earthquakes
The delineation of active faults becomes an urgent necessity.
Many damsites in tire world have been constructed on active
faults and the knowledge of the distribution of such faults,
especially w'hen they are associated with earthquake hypo-and
epi-centres might help to mitigate larger losses due to dam
collapses and landslides, as well as by direct earthquake damage.
Active faults in many cases can be delineated on remotely sensed
optical, thermal (TRONIN, A. A. 1996) and radar images. They
occur in regionally different patterns, and the knowledge of these
patterns, the reconstruction of the kind of movements along the
faults, and their connection with active volcanoes will greatly
help in the assessment of geological hazards.
4. THE ROLE OF UNESCO/IUGS GARS-PROGRAM IN
NATURAL HAZARDS PREDICTION AND
MONITORING
The GARS- (Geological Application of Remote Sensing)
Program (LEROI, E. et al 1995) is an international co-operation
programme jointly sponsored by UNESCO and IUGS. It had
been initiated 1983 with the aims
1) to demonstrate the use of adv anced remote sensing techniques
for the solution of key geological questions
2) to ensure the transfer of information and technology through
co-operative research in the field in combination with educational
programmes
3) to ensure wide dissemination of results
The project is currently in its tliird pliase.
The objectives of Phase 1 were
- to develop new methods for the integration of multisensor data
to improve lithologic mapping in tropical environments (East-
Airica)
The objectives of Phase 2 were
- landslide mapping using GIS teclmology based on satellite data
and new Radar information on test sites in Colombia
The objectives of Phase 3 are
- to demonstrate the use of remote sensing, SAR in particular,
for the analysis of volcanic and associate hazards in the
Philippines
UNESCO and IUGS science policy asks for the promotion of
new techniques in the field of earth sciences and to involve
scientists from developing countries by co-operative research,
training and technology transfer. Usually, research programs are
initiated between two or more partners at key geological or
geological / environmental problems.
Phase 1, the multisensor data for lithologic mapping in Eastern
Africa is now in the technology transfer phase, during which the
Royal Museum for Central Africa is introducing the PANGIS hard-
and software programme in 13 African institutes, mostly national
geological surveys.
Phase 2. the landslide project is now in its world-wide application
phase. A training programme lias been developed by ITC, called
GISSIZ (Geograpliic Information Systems in Slope Instability
Zonation, VAN WESTER C. J. 1993). ITC with funding from the
European Union developed and distributes this training package
world-wide. The GISSIZ includes besides Geological
information, DTM, based on SPOT-stereo and ERS-radar data,
and rainfall data.
Phase 3 is currently in its final period. Main emphasis of the program
lies on the application of radar data for terrain modelling in the
Philippines. However, the interpretation of various image products,
like SPOT-VHR and PAN data and others is still a main constituent
of the research of various groups. Currently, thermal data is gathered
International Archives of Photogrammetry and Remote Sensing. Vol. XXXII Part 7C2, UNISPACE III, Vienna, 1999
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