Air Quality Information Systems and geoss: Applications to India

Technical/Management Section

Background of Air Quality Monitoring in India

The Central Pollution Control Board (CPCB) and State Pollution Control Boards (SPCBs) are the government agencies responsible for managing air quality at national and state levels. The ground based monitoring networks in India include the National Ambient Monitoring Programme (NAMP) network operated under the guidelines of Central Pollution Control Board, state level air monitoring networks operated by respective State Pollution Control Boards, and other networks operated by the National Environmental Engineering Research Institute (NEERI), universities and research groups. Studies on the health impact of air pollution in India have been limited and the high pollution levels in a large number of cities with high population densities are a cause for concern. An example issue in need of improved decision support tools and technologies is the impact on crops due to ozone and climate change, including early warning systems and public service bulletins to targeted communities.

The NAMP network consists of 342 operating stations within 127 cities in 26 states and 4 Union Territories of the country. All these stations monitor sulfur dioxide (SO₂), nitrogen dioxide (NO₂), Respirable Suspended Particulate Matter (RSPM) and Suspended Particulate Matter (SPM) ), Ammonia and Hydrogen Sulphide on every third day. More than 100 continuous monitoring stations have been also commissioned by CPCB, SPCB’s and the Industry in cities of concern such as Mumbai, Delhi, Pune, etc. Periodically, heavy metals in PM and PAHs are also analyzed from many of these stations.

Major Issues with Air Quality Monitoring System

The present system of measurement does serve a purpose of providing city specific plan however, it has limited role in terms of understanding of little extended region around these cities. The point measurements from the monitoring stations are thus limited in their temporal frequency and geographic coverage, and lack the spatial continuity to provide a synoptic view of air quality in the region. The current monitoring network also lacks monitoring in rural areas that are impacted by pollution transport downwind of urban and industrialized areas. The other related problem is with regard to data of background against which the cities air quality can be compared. The background data points are very limited compared to urban centric or industrial clusters data from monitoring stations. With the addition of continuous monitoring stations is some cities, issue pertaining to inter-comparison of data within the cities as also across the country, becomes a major concern.

Responses needed

Additional modes of monitoring are needed to better assess air quality and recent developments in the earth observation (EO) systems provide an excellent opportunity to integrate satellite data with surface measurements to support the decision-making processes for effective air quality management. Presently, these data are not utilized to their full potential for air quality management in India, and are, for the most part, limited to the research community. The opportunity to find, access and understand air quality data from different sources for examining, processing, overlaying and displaying would offer an added dimension to the air quality management processes in the country.

The GEOSS vision provides a structure for environmental data to be easily available through an interoperability framework that allows them to be used via various subsets and combinations in support specific research and decision applications (Figure 1).

Figure 1: GEOSS connecting observation and modeling systems with decision processes

The use of data and their application for air quality achieved in GEOSS through web and data standards would allow disparate data to be accessible to a variety of decision support tools. The GEOSS Common Infrastructure (GCI) on one hand would provide a channel for data providers to register and catalog standards-based web service interfaces to satellite, surface and modeled data, and on the other hand, for data consumers to find and access those data.

The atmospheric composition over India is determined by the sources within India as well as by the contributions from neighboring regions. A full air quality characterization requires a multi-scale approach, consisting of global, regional/national and local perspectives as depicted in Figure 2. Global data, analyses and models provide the broad geographic and chemical pattern and visualize pollutant transport into and out of the Indian sub-continent. Surface observations are inherently local and the analysis of local conditions is necessary for the full understanding of air quality, particularly in mega-cities and industrial areas. Air quality monitoring networks managed by the Indian national agencies provide important observation data that can be augmented with satellite data and model results.

It is anticipated that a key contribution of the proposed project will be the India-scale characterization of air quality facilitated by the Indian and GEOSS Air Quality Communities of Practice (AQ CoPs). The regional/India-scale observations, analyses and modeling results can be synthesized from the combination of global observations provided by the GEO AQ CoP and national observations within India.

Figure 2. Multi-scale perspective needed for AQ characterization

This proposal focuses on strengthening and developing new capabilities for Indian air quality management activities, which has ample intellectual capacity to benefit from such infusion in a few key areas, and which could be expected to carry the program forward operationally on its own in approximately 3-4 years. This is a reasonable estimate for the development of a prototype system that is ready to be transitioned into an operational system for routine applications based on experience in related projects to develop air quality decision support systems in the U.S.