Spreading the benefits of space technology.

The UNISPACE 82 Conference discussed how all States could take advantage of space technology for economic and social development and benefit from using satellite remote sensing systems to develop and monitor their natural resources and the environment.

In the short term at least, access by all countries to the full range of space activities would require co-operation between developed and developing countries, the Conference stated, recommending that technologically advanced countries with facilities for launching satellites, conducting experimental activities in space, operating remote sensing systems or manufacturing advanced components or systems should make these facilities accessible to developing countries.

The study (A/AC.105/339 and Add.1)--"Assistance to Countries in Studying their Remote Sensing Needs and Assessing Appropriate Systems for Meeting such Needs'--was prepared by a group of experts from 11 nations: Argentina, Austria, Burkina Faso, Chile, China, Egypt, France, German Democratic Republic, Netherlands, Philippines and USSR.

Among the various possible approaches to international co-operation in remote sensing might be a simple, low-cost, internationally owned satellite data system that could make information obtained from space readily available to all nations on earth. Such a system could be based on technology of proven reliability and would be able to make data available to all countries through relatively simple national or regional ground stations. The system could be launched at a significantly lower cost than the experimental satellites that individual nations would continue to operate.

A first step towards its establishment could be creation of a group of interested countries, both space powers and major users of satellite information, to discuss organizational and financial arrangements of the system.

By the mid-1990s, if remote sensing activities were pursued nationally and co-operatively in a vigourous manner, the techology would be firmly established. Plans are alread under way for a second-generation of regionally and nationally owned remote sensing satellite systems to be in place by the mid-1990s.

Preparations for a third-generation high resolution remote sensing satellite system for use in the late 1990s or during the first decade of the 21st century should be undertaken now, taking into consideration identified needs and existing and planned satellite systems.

The report also recommended:

* Consideration of a proposal for a three-year United Nations project to define remote sensing systems to satisfy developing country needs, possibly followed by establishment of an international consortium to build and operate remote sensing systems.

* Compiling a regularly updated catalogue on how satellite remote sensing is being used, including such information as project description, sponsors and major results, which could form a part of the United Nations directory of space information and data services;

* Creating a world-wide or regional archive for remote sensing data for research in developing countries.

* Setting up "centres of excellence" in nations or regions to advise scientists and institutions in developing countries on processing, application, distribution and verification of remote sensing data;

* Offering courses at the "centres of excellence", organized by United Nations agencies, to inform regional scientists on advances made in remote sensing, to train users in depth in applications of remote sensing techniques and data to solve regional problems, and to organize, with local users, ground truth campaigns and research projects;

* Nomination by Member States of outstanding scientists and technicians for teaching and research at these centres.

International co-operation: For the next several years, at least, remote sensing systems will remain national undertakings, designed, built, financed and operated by one country that sets terms for making data or ground station agreements available to others.

Proposals have been made to establish a broad-based organization to coordinate or even own and operate remote sensing satellites, which could be modelled on such organizations as the World Meteorological Organization (WMO), which co-orindates activities of nationally-owned and operated weather satellities, or the International Telecommunications Satellite Organization (INTELSAT), which operates its own communication satellites. INTELSAT members contribute to the capital expenses of its system by paying in proportion to use, and users pay commercial fees for services.

If user countries want a satellite system able to meet their needs continually, a forum for voluntary co-ordination is not sufficient. An international organization to design and operate the satellites would be required, as well as a global network of national or regional ground stations, with financial participation of all countries wishing a voice in the decision-making process. With wide participation, such a satellite system could provide assurances of continuity even if individual countries joined or withdrew.

The organization could be set up as a subsidized public service, rather than a commercial fee-for-service operation like INTELSAT. Expensive satellite technology would prevent such an organization from covering expenses by selling its product--information--for reasonable fees. If, for example, the satellite system cost $100 million annually to build, launch and operate, and if the demand for data were 100,000 scenes per year--somewhat higher than current global demand--the cost per scene would be a prohibitive $1,000.

A subsidized public service organization could take as a model the participation of European countries in the European Space Agency (ESA) and the newly-created European Meteorological Satellite Organization. The international remote sensing satellite system would be made up of countries agreeing on a common programme, a common budget and the division of expenses among themselves. All nations could be welcome to join, while staffing of the organization and contracting of work could accord with the financial share of each member.

There seems to be little advantage to organizing an integrated global network of ground stations. Informal international co-operation between regionally or nationally owned and operated stations would suffice.

Other proposals: Countries could share remote sensing technology and information by involving technicians from developing countries in specific projects so they can gain practical experience; establishing bilateral and multilateral partnerships for assistance in introducing and advanced methods of interpreting satellite data; and creating national depositories of satellite information, a world index of space imagery and a system to exchange these data through a global network of computer terminals.

Uses of data

The term "remote sensing" usually refers to acquisition of information, including photographic images, about the earth's surface from instruments aboard airplanes or satellites orbiting the planet. These data are then used to make maps, survey disasters, inventory resources and monitor environmental events.

Remote sensing data can be used, the report states, in increasing economic productivity of both renewable resources, notably crops and timber, and non-renewable resources such as oil and minerals; in national or regional planning with the goal of long-term economic and social development; and in monitoring the environment to improve the quality of life.

Land observation satellites are currently operated by the United States (Landsat, SIR), USSR (Soyuz, Salyut, Cosmos, Meteor), India (Bhaskara), and the ESA (Spacelab). Projects are under development by France (SPOT), India (IRS), Japan (JERS), ESA (ERS-2), and the Netherlands and Indonesia (Tropical Earth Resource Satellite).

Only the United States currently has launched marine observation satellites (Seasat, Nimbus-7); such systems are being developed by Japan (MOS-1), ESA (ERS-1) and Canada (Radarsat).

Two co-ordinating groups have been set up--one for land observation satellites (United States, France, India), the other for ocean observation satellites (United States, ESA, Japan)--to exchange information and consider ways to maximize the compatibility of various space missions. However, there is to date no group in which "purely user countries" can express their views.

Oil and mining industries--which need to observe vast tracts of the earth for geological exploration and which have the finances and technical expertise needed to make use of the technology--are the major users of satellite data for non-renewable resources.

In the area of renewable resources, remote sensing is used to manage forest resources, assess current or potential land use and survey soil and landforms, determine distribution and marketing plans for harvests, and make regional or global crop estimates. Experiments on assessing and monitoring agricultural drought, soil moisture and crop conditions are under way.

The technology may also be used in major building projects such as construction of roads or pipelines. Ocean-monitoring satellites may contribute to improved fisheries production by pin-pointing food-rich zones that attract fish; or assist in ship routing, to improve the efficiency of commercial shipping.

An obstacle in making crop estimates is cloud cover interference with satellite data collection, particularly in countries with a long rainy season. To be useful, crop estimates must be based on information frequently supplied and speedily distributed. Furthermore, a reliable network for disseminating data and an organized data base integrated into national farm distribution and marketing systems must exist.

Remote sensing can be helpful in arid and semi-arid regions for tracking brush fires, identifying areas damaged by overgrazing, monitoring range conditions, and studying problems related to desertification.

The technology can help monitor air and water quality, identify sources of pollution and elements of climate systems and desertification processes, and provide information on flood water advance and retreat and data for mapping of flood plains.

Costs: Most nations now buy data in the form of photographs or computer tapes; some operate ground stations, thus receiving information directly for processing; a few others operate entire systems, including launching satellites, data collection, processing, analysis and distribution.

Costs range from as low as a few thousand dollars annually for the purchase of imagery to about $100 million yearly for assembling and operating an entire system. Operatio of a ground station runs to several million dollars a year.

Prices for data may rise significantly in years to come, and the implications for applications and for demand should be considered. Price increases, especially for data that need frequent updating, could discourage use of remote sensing by developing countries.

A ground station receiving information from Landsat-4 and 5, two American satellites, could receive about 1,500 useful scenes a year. If amortization of capital expenses, operation of the station and user fees amounted to about $3 million a year, the cost-per-useful-scene would amount to $2,000. Using the French SPOT satellite, the same station could obtain about 8,000 useful scenes per year for $400 per-useful-scene.

The cost-per-image varies with the number of times the average scene is reproduced. In 1981, the 11 ground stations operating outside the United States distributed about 22,000 scenes of Landsat data, an average of 2,000 scenes per ground station. At prices set by ground stations, the data cost $2.4 million--about $220,000 per ground station. Given the present level of demand for data, ground stations cannot cover capital and operating costs through data sales.

Systems to analyze and interpret satellite information range from homebuilt light boxes with tracing paper and coloured pencils to large computer systems. Some countries may wish to develop their own analyzing capabilities either out of a desire to be self-reliant or because establishing dependable contacts with outside suppliers is difficult. Operating maintaining and repairing image analysis equipment is difficult, and in many cases, equipment lies unused because the difficulty of using it outweighs its practical use.

The capabilities of image processing systems have rapidly improved in recent years, while cost has declined. Once costing about $1 million, systems today are available from $50,000 to $300,000.

Assessing Needs: Countries planning to make use of remote sensing need to consider such problems as distribution of the satellite data, training of personnel to run a system, and financing.

The extent to which use is made of remote sensing data depends on ease of access to the data and availability of processing and interpreting facilities. It is often most economical to establish a central complex for expensive operations along with simple, decentralized facilities in the agencies which actually use the information.

A first step in establishing a central facility would be creation of a national satellite data library with a photography laboratory for reproducing imagery as needed by users.