Excerpts from an article contributed to excite commerce graduate students

 ABSTRACT

The new dictum for development is sustainability such that the natural resources are utilized most efficiently with no/almost-nil adverse impact on environment. This thinking on sustainable development, obviously, requires adequate legal & executive enforcement procedures supported by robust and dependable observational systems and analysis tools. From the vantage point in space, satellite platforms have great advantage in providing increased satisfaction for observational and communication support to this requirement. Very significant progress has been achieved in India in utilizing satellite technology for national development.

 Introduction:

Throughout recorded history, the exploitation of natural resources has been given primary focus for economic development. Unfortunately, the same has been the source of greatest disputes among nations and states, since environment and distribution of natural resources on earth have no national/state boundaries. An unhindered and un-thoughtful exploitation of the same has also resulted in large scale depletion for future availability of these resources. The possibility that the earth will be irreparably damaged due to these actions has finally dawned upon the global leaders resulting in the first Earth Summit in 1992 at Rio-de-Janario in Brazil; whereupon, there has been a global agreement under UN aegis that all developmental activities henceforth will be subjected to “sustainability such that our future generations have un-compromised rights in terms of availability of these resources”. This concept of sustainability has been framed in terms of the famed Agenda 21 adopted at this Earth Summit. It has also been recognized during these deliberations that the global environment has an intimate connection with the development efforts and damage to it will not only be a local issue but will also be global. There have been numerous frame work conventions and protocols since then to formulate procedures for an environmental friendly development and cleaner living conditions for the 8-billion plus inhabitants of the earth.

The design for sustainability is not very easy, since it requires at all stages compatible technological support, observation systems for key parameters, information and dissemination systems to share information across board, economic projection models to determine viability of the project, societal impact analysis to determine its acceptance, legal & executive framework to deter abrasions and education and awareness creation for all stake holders. The information creation and dissemination system have largely been supported by satellite technologies. The legal and procedural support to decision making has been possible using international frameworks and protocols and almost all nations of the world have agreed to setup Green Tribunals and Authorities. (One such initiative has been taken by India in April 2015). Simultaneously, the scientists and mathematicians have been adding teeth to data analysis techniques to provide real time information. The economy, which earlier used to be presumptive planning, is now becoming more predictable (or rather objective).

The information gathering and its dissemination to users has been exemplary supported by advances in communication technology, information analysis techniques, observation support from satellite based remote sensing, query based uploading and downloading of data from unsupervised system, very fast computing systems, extremely large data bank and newer and efficient analysis tools and software development. These have formed basic brickwork for supporting decision for all aspect of design and execution/operational management for development. Space observations provide synoptic and repetitive coverage whilst the in-situ observations, though sparse and limited, support remote observations in terms of assuring the quality and validity.

• Applications of satellite observations for development
• Mapping and estimate of natural resources:

1. Environmental monitoring:
   1. Pollution dispersal: The atmospheric boundary layer winds, temperature, humidity, stream water temperature, water colour, sediments, currents can be measured and forecast using satellite data and numerical models. A regular monitoring of concentration of pollutants can be made by autonomous stations relaying information to remote analysis systems enabling modeling, estimate and forecast of pollution dispersal in terms of air and water quality indices.
   2. Weather forecast: The most successful endeavor of satellite technology has been demonstrated in the field of weather forecasting, right from instant weather observation to the forecast of dry & wet spells, heat & cold waves, frost, precipitation & snow fall etc. The marine state forecasts support the shipping industry. High altitude forecasts for snow and avalanches are also facilitated by satellite observations. Instant floods can be easily forecast using high resolution geostationary satellites.
   3. monsoon forecast: Satellite data have unique property of providing synoptic information on larger spatial scale. Therefore, is most ideal for forecasting and monitoring progress of monsoon, the rainfall and events of scanty and heavy rainfall to support decision making and mitigation efforts at the farming level.
   4. Climate forecast: Large scale droughts, frequent water logging, seasonal concentration of vectors bearing serious diseases likes dengue etc., can be monitored using satellite observations. The changes in climate can be estimated and plans can be prepared to mitigate the situation.
2. Natural resources: Most satellite images in multi-band can be interpreted in terms of estimates for natural resources like minerals, water, forests, fisheries and agricultural output.
   1. water quality: The quality of available potable and commercial water can be estimated and monitored using satellite data in consonant in-situ observations.
   2. Off-shore oil & Gas, and mineral exploration: The production of offshore oil and gas is rapidly expanding. It has been estimated that the largest reserves lie in much deeper water at great distances from shore. The environmental data upon which to base design of extraction systems, management and operations decisions are available relatively easily from satellite observations supported by relayed data from data platforms.
   3. Genetic diversity and pharmaceuticals: The living resources especially in coastal regions provide an ample scope for extraction of drugs and chemicals for medicinal and other purposes. Biodiversity mapping and its transgression has been demonstrated to a high order of acceptance using satellite data.
   4. Energy: Apart from mineralized fuel supplies from coal, gas and crude oil for power generation, alternate sources of power, non-polluting and sustainable, can be found and potential estimated using satellite observations specially for solar energy harnessing, energy from ocean waves, tides, and thermal structures, coastal and in land winds for wind energy.
3. Defense,  security and disaster management:
   1. Ship detection: The ship on movement produce a distinct wake which can be easily seen using a Doppler filter on a SAR image. The Doppler shift can provide the speed and direction of the ship. This information is very useful for open sea policing purposes.
   2. Underwater operations: Satellite oceanography provides a very potent tool for mapping Sub-surface Ocean features facilitating operation of underwater equipment for exploration and defense applications.
   3. Support to aviation: High resolution numerical weather forecast models incorporating satellite and autonomous weather station inputs are providing very useful information for aviation both civilian and defense.
   4.  Oil spill and environmental monitoring: Due to the oil spill, the ocean surface roughness will change quite drastically. Hence, an image of SAR will provide clues to this by comparison of the surface roughness signatures.
   5. Tropical cyclones: The intensity and movement of tropical cyclones can be monitored through continuous monitoring from geostationary satellites supported by low orbiting satellites to provide estimates for storm surge are being done routinely to provide support for disaster management.
4.  Other support:
   1. Transportation and trade: Surface transport still remains the cheapest means of transporting the cargo across nations. Trains, trucks, ships, particularly oil tankers and container ships, have become progressively larger to reduce unit cost in transportation. These larger units, now require increasingly support from satellite GPS for navigation, instant weather and forecast of efficient route for pilot health, service quality and time management.
   2. Urban & rural planning: The increasing population and requirements for increasing commercial activities are putting strain on existing infrastructures. Therefore, there is an increasing need to setup new urban centres. The lesser availability of land area for this purpose is mounting pressure to adopt more efficient planning. The government of India has taken very definitive steps in this direction by introducing the concept of medium scale smart cities. Satellites play major supportive role in this planning.

waste disposal: For all urban and rural centres, the major hurdle for development is waste disposal. The present centralized waste-treatment is turning out very expensive and technologically inefficient. The  de-centralized system requires synoptic pattern of waste generation, waste classification and possibilities for de-centralized waste treatment to reduce volume and get utilizable bio and energy resources as bye product.

1. Space-borne sensors used in environmental and resource planning:All space-borne sensors use some part of the electromagnetic (EM) energy, either naturally emitted from sun or earth (passive mode) or artificially radiated using a LIDAR or RADAR (active mode). Atmosphere is an all-pervading medium through which observation of any oceanic process from a space platform needs to be carried out.  The part of EM spectrum for which atmosphere is transparent is treated as atmospheric windows for operation of sensors and provides the most useful coverage of earth surface. However, for these window sections of EM spectrum, one of the major limitations arises due to cloud cover. The microwave part of EM spectrum is relatively transparent to presence of clouds; therefore, the fourth generation satellite information systems integrate all parts of EM for observations in terms of a system of satellites.

   Level of information from satellites