International workshop on global databases

International workshop on global databases

32 package for automatic processing of three line-Stereo images, With the first version of this software digital terrain models of regions in Austral...

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package for automatic processing of three line-Stereo images, With the first version of this software digital terrain models of regions in Australia, Bolivia, Mexico and Ethiopia have been derived. The obtained point accuracy is in the order of one pixel (13.5 m) and is somewhat below the expected value. The reason for this fact can be found in the insufficient geometric calibration and the not quite precise information on the exterior orientation of the camera. So far only the forward- and backward-looking channels (13.5 m) have been used for stereoscopic evaluation. An improvement in point accuracy is expected by including the high-resolution nadir channel (4.5 m) in the evaluation process. With this high-resolution channel, J. Schiewe (University of Hannover) produced an 1 : 25,000 orthophoto map of an urban area with 4-m planimetric accuracy. Impressive was also a video produced by M. Lehner and W. Kornus (DLR) showing a flight simulation through the Bolivian Andes derived directly from MOMS-02/D2 data. The presented studies with MOMS stereo data have proved that digital evaluation of 3-line space images is feasible and leads to promising results. The thematic analysis of the multispectral imagery was coordinated by J. Bodechtel (University of Munich), The position of the MOMS spectral channels corresponds nearly to the visible and NIR channels of the Thematic Mapper, but the band widths are significantly smaller. By this means the differentiation of vegetation types should be improved. The applications for which MOMS data were used included forestry and land-use studies in tropical zones, geology and geomorphology of arid and sand desert areas as well as studies on coastal zones. Many speakers regarded the combination of the high-resolution channel (4.5 m) with the multispectral channels as very suitable for recognition and interpretation of objects. The high quality of the MOMS data was clearly demonstrated by H. Kaufmann’s (Geo Research Centre Potsdam) investigations on population statistics in Zimbabwe, which were based on the recognizability of single houses. The afternoon of the second day concentrated on the reflight of the MOMS-02 camera on the Russian PRIRODA mission and was mainly formed by presentations by Russian colleagues. Early 1996, PRIRODA will be docked to the Russian Space Station MIR, which circles around the earth in a 400-km orbit with 51.6” inclination. From this orbit the MOMS ground resolution will be 18 m and 6 m (high resolution). A high-precision navigation package consisting of an INS and GPS ensures synchronization between imagery and navigation data to 0.1 ms. The mission duration will be approx. 18 months. N. Armand (Academy of Science, Moscow), in his Position as scientific coordinator for PRIRODA, gave an overview on the mission objectives and instru-

ISPRS Journal of Photogrammety and Remote Sensing mentation. Beside MOMS, other sensors as well as a radar syste The field of applications planned wi Russian scientists comprises soil type and soil erosion mapping, snow and ice studies, hydrology of large river systems and geological mapping. The last day was occupied with future ca missions in space. Out of app’rox. 50 earth observation satellites planned for the next decade, only a few are dedicated to topographic mapping. SPOT-5 (year 2003) will be equipped with an along-track stereo capability of 5-m ground resolution. For the year 2001, Japan is planning the ALOS-satellite with a 2.5-m-resolution 3-line stereo imager. L. Fritz (ISPRS Secretary General) reported on the intentions of three US companies to commercialize earth observation satellites. One of these companies, Earth Watch, will launch the Early Bird satellite with a 3-m resolution stereo sensor as early as April 1996. A second satellite, Quick Bird, with a l-m resolution will follow in 1997. The prices for these satellite data will correspond to those of aerial photographs. There are also considerations in Germany for a commercialized MOMS mission from 1996 on. Therefore, the concluding panel discussion chaired by F Ackermann dealt with market perspectives of MOMS products in a competitive environment. The 18-months PRIRODA mission was regarded as very favourable for preparation of the market. The panellists agreed that the MOMS techniques, especially the 3-line stereo imaging method, will be appropriate in future commercial missions. The participants left the symposium with the certain impression that the next generation of space sensors with increased spatial resolution and with stereo capability will be launched in the near future and that the commercialization of satellite earth observation is growing. They can only hope that due to competition the prices will go down. Proceedings of the meeting will be published by EARSeL and can be requested from: EARSeL, 2, Avenue Rapp, 75340 Paris Cedex 07, France; fax: t.33 (1) 45567361. M. Schroeder (Wessling, Germany)

International Workshop on Global Databases June l-2, 1995, Boulder, Colorado, USA The sponsoring organizations were ISPRS WG IV/6 (chairman, Ryutaro Tateishi; co-chairman, Hiroshi Murakami) and the Japan Society of Photogrammetry and Remote Sensing. The workshop was jointly held with the Globa! Land One-km Base Elevation (GLOBE) meeting (chairman, David Hastings) which was held from June 1 to 2 at the National Geophysical Data Center,

order to identify problems and improve Therefore, the most im s of the works were the discussions o databases such as data requirements, legen harmonization of various projects. From this meeting it is clear that many agencies are cooperating in making basic global data or tee available. These include: - NOAA GDC (D. Hastings): making global-change data sets available. - Rutgers University (S. adry): providing hundreds of raster, vector and point- ta global maps in a single GIS format. - US Army CERL (R. Lozar): developing soil identification procedures based on EOS Pathfinder data sets. - CIESIN (Darrel Charache): socio-economic information for global change. - DMA (K. Littlefield): declassified topographic (and other) data sets. - University of Tokyo (D. Dye): developing a glo solar radiation set for photosynthetically active radiation (PAR), absorbed photosynthetically active radiation (APAR), and net ecosystem carbon exchange. - Chiba University (R. Tateishi): developing data sets from remote sensing and ground data for evapotranspiration (1994) and a 8-km Asian land cover data set (by 1996). - World Games Institute (A. Gabel): global socioeconomic-environmental data based on UN, WHO and World Bank reports. - US Geologic Survey EROS Center (J. Brown): developing a l-km global land cover based on AVHRR sensors, to be finished by October 1996. - University of Belgium (C. Vits): modelling tropical forests for Central Africa for estimation of forest biomass. R. Pielke (Colorado State University) discussed landuse resolution needs. A lo-km resolution is inadequate. Man’s land-use modifications (the biggest in the section of agricultural) result in CO2 modification equal to the CO2 impact on global climatic change. For the differ-

ital terrain ejev of the world (D

model. They are similar to the University of unning) models in that they remove climatic concerns from the remote sensing process. They are based on three canopy components: above-ground biomass; leaf longevity, and leaf type. The procedure results in seventeen mostly stable classes. Problem areas are numerous because so many e applications. users have different needs and ulti ller (University Geographic projections worried J.P of London) and R. Shibasaki (University of Tokyo). D is producing global data using the WGS84 standard, so how can we link all other maps available to the WGS84? Mean sea level is different in different areas of the world so how do you link them all up? Spectral decomposition cannot be done without projection distortion. In a discussion on land cover legend/categorizations, R. Tateishi found the user community to have diverse needs with respect to ground truth for the AVHRR sensing. The categorization must reflect the needs, but many different needs were expressed. A hierarchical system provides greater versatility and longevity. The UNEP/FAO has a contract with the Institute of Terrestrial Ecology in Great Britain to provide translations between systems. Data accuracy and quality goes down on a statistical error budget basis. A recent DMA document dedicates a chapter to the question of accuracy for both features and terrain. The group’s recommendation was that accuracy should be dependent on: (1) a minimum set of historical information; (2) the use of automated

34 software for reliable data manipulations; and (3) the adherence to the metadata standards accuracy component. The data availability group (Dr. Ojima) was concerned about access to published, unpublished (on the internet) data and copyrighted data (restrictions seem to be increasing). As an example, SPOT claims copyright to even value-added data so it is attempting to embed the company name directly into the data. It is clear that there will be many contributions from a variety of groups (Dr. Madry). These include data from the scientific, educational, commercial, and applications sectors. There will be a need for scalability (from


of Photogrammetry

and Remote Sensing

local to national to regional), for temporal c uation, for metadata and interoperability, an ancillary data (socio-demographic, energy, oceans, atmosphere, and better-defined political boundaries). The Report of the International Workshop on Global Databases (67 pages, in: International Archives of Photogrammetry and Remote Sensing, Vol. XXX, part is available from RIGS Books, Surveyor Court, Westwood Way, Conventry CV4 8JE, UK; fax: 3-44 (71) 334-3800. R. Tateishi (Chiba, Japan) R. Lozar (Champaign, IL, USA)