global systems for sharing natural disaster information,
especially maps and data generated by remote and
land-based sensors)
In a similar way, the synergetic impact of remote sensing
and the Gl will be the major theme of the ISPRS Congress
in Amsterdam, selecting the motto “Geoinformation for
All". Commission VII proposed its technical session related
to this Congress theme be entitled "Resource and envi-
ronmental monitoring — local, regional, global" with key-
words data availability, accessibility, application-oriented
data requirements, interoperability, spatial data infrastruc-
tures, remote sensing applications, Agenda 21, UN Inter-
national Decade for Natural Disaster Mitigation.
Fundamental Research and Development on Physical
Measurements and Signatures in Remote Sensing
The widest range of results in the fundamental research
and development on physical measurements and signa-
tures in remote sensing were highlighted and discussed
under the ISPRS logo at the last Courchevel international
conference organised by CNES, and JRC SAI of the Euro-
pean Commission. The topics included physical modelling
for data simulation and sensitivity studies (e.g. in agricul-
ture, recovering surface temperature and emissivity from
thermal infrared multispectral data), inversion methods
(used e.g. in satellite measurements and vegetation mod-
els for carbon cycle studies). In data pre-processing
mostly the AVHRR, SPOT, ERS data were handled, also
paying attention to the atmospheric influences on field
spectrometry (i.e. the observed relationship between
spectral irradiance and the variance in spectral
reflectance). The atmospheric correction for short-wave
sensors (e.g. MODIS, POLDER, VEGETATION, MERIS)
have also been investigated. The physical modelling using
experimental test areas for calibration of satellite sensors
focused on coupling ground, airborne and Earth observa-
tion data. Investigations were mostly related to agriculture,
highlighted by leading laboratories such as INRA, USDA
RSRL, JRC SAI and CESBIO. As examples, assessment
directional properties of emissivity and radiative tempera-
ture of vegetal covers, use of stochastical model for deter-
mination of leaf properties in the optical range, bi-direc-
tional measurements of leaf reflectance and transmittance
as far as different land cover types and surface compo-
nents to standardise vegetation indices or analysis of
model sensitivity due to the impact of spatial and tempo-
ral variability of canopy and soil characteristics can be
mentioned. The use of 3-D plant modelling and measure-
ment in remote sensing was also introduced. The estima-
tion of bio- and geo-physical/chemical variables was
reviewed in depth. The application-oriented developments
include land-use classification with the aid of neural net-
works, land subsidence mapping by differential SAR inter-
ferometry and modelling and characterisation of soil salin-
ity in irrigation systems, as well as monitoring urbanisation
and de-forestation using remotely sensed data. Using
AVIRIS data-based algorithm, about 1 million reflectance
spectra have been analysed, showing a range of spectral
characteristics indicative of vegetation species. The "leaf
water parameter" has been derived, which is shown to be
strong indicator of leaf thickness and canopy spectra. Due
to the fact that monitoring agricultural crops and estimat-
ing yields has become an issue of great importance, both
for economic planners and for agribusiness, assimilation
198— ——
of satellite data in crop monitoring and yield prediction has
also been targeted. The technology has also been devel-
oped in small countries (such as Hungary, where - based
on a 20 years R+TD with 300 man-year investment at
FOMI RSC - crop monitoring and yield estimation by mul-
tiplatform satellite remote sensing is operationally used
and has been serving the decision-makers since 1997).
The opportunities for, and limitations of remote sensing in
precision farming were recalled by S. Moran at al describ-
ing four major requirements as follows:
- Real-time information for on-the-go management
- Information on seasonally stable conditions (mapping
long-term variability)
- Information on seasonally variable conditions (mapping
short-term variability), and
- Information required to determine cause of variability
and develop a management strategy.
Another field of investigations was the remote sensing-
based impact assessments of environmental change, with
targets estimating the status of terrestrial vegetation and
with special emphasis on the tropical forests, the monitor-
ing of urbanisation and analysis of enhanced plant growth
in the high latitudes of the Northern Hemisphere. The VEG-
ETATION potential for desertification monitoring, simula-
tion of sand movement detection in Northern Africa, syn-
ergistic use of passive and active microwaves over
semi-arid and peri-artic regions, as well as discrimination
of wetland and non-wetland community types with multi-
spectral, multi-angle polarised POLDER data were high-
lighted and discussed.
Instruments Introduced in Application-oriented
Environment at ISPRS Commission VII Related
Conferences and Symposia
The most widely used sensors include AVHRR, Landsat,
SPOT, IRS, ERS, JERS, METEOSAT, RADARSAT, MOMS-
Priroda, KVR-1000 and SPIN-2. The ISPRS-CNES-JRC
Courchevel conference and ISPRS-ISSSR symposia high-
lighted the following airborne or space remote sensing
instruments:
- AVIRIS NASAs airborne visible/infrared imaging spec-
trometer (used in spectral reflectance studies by R.
Green of NASA JPL and D. Roberts of UCSB)
- J|RSUTE - a minisatellite project for land surface fluxes
estimation using hi-spatial resolution thermal infrared
(introduced by B. Seguin at al, of INRA, LSIIT-ENSPS
and CNES)
- MERIS - medium resolution imaging spectrometer (intro-
duced by ESA HQ and ESA/ESTEC, as well as by Jan
G.P.W. Clevers of Wageningen University, Co-chair of
ISPRS WG VII/1)
- SARinterferometry and its use (M. Zink et al of DLR)
- HSSL (Hot-Spot Search Light) using active illumination
and multi-directional detection that would allow hotspot
angular distribution measurements from space in a
searchlight mode in order to retrieve leaf size and
canopy height (introduced by A. Gerstl of Los Alamos
Nat. Lab.)
- Positive Systems's HYDICE hyperspectral push-broom
sensor (introduced by R. Pollina et al of Bechtel Nevada)
- Operational Hyperspectral Imager (introduced by
Dornier-GeoFZ-CCRS)
- COIS (NEMO) and Warfighter (OrbView-4) and Hyperion
- International Archives of Photogrammerty and Remote Sensing. Vol. XXXIII, Part A. Amsterdam 2000.
