Weathering Heights: India Launches INSAT-3D Meteorological Satellite


On July 26, 2013 India’s dedicated meteorological satellite INSAT-3D was successfully launched into a Geosynchronous Transfer Orbit (GTO) by Ariane-5 VA-214 launch vehicle from Kourou, French Guiana. This satellite has been designed and developed by India Space Research Organization (ISRO). The process of orbit raising maneuvers is under progress to place it in the 36,000 km high Geostationary Orbit. Even though the satellite was launched by a French rocket it is also important to note that after initial injection into the transfer orbit (GTO) by the French rocket the satellite itself performs the further maneuvering to reach to the Geostationary Orbit. The satellite’s own propulsion system is being used for this purpose. To conduct this orbit raising activity the satellite had carried more than 1000 kg of propellant. Finally, the satellite would be placed at 82 deg East orbital slot and is expected to become operation with a week’s time after the launch.


India already has two operational meteorological satellites (MetSats) called KALPANA and INSAT-3A in space. They are providing cloud imageries in various categories. INSAT-3D offers significant amount of improvements over these predecessors. It offers far better cloud imagery in respect of weather phenomena like low clouds and fog which are usually difficult to judge in normal satellite imagery. This new satellite would also offer estimation of Sea Surface Temperature (SST) with much better accuracy. These inputs are essential for various purposes like they help in forecasting of monsoon, forecasting of tropical cyclones and of utility for the fishery industry because presence of fish in particular portion of sea depends on the temperature conductions at the sea.


The INSAT-3D is expected to add a new dimension to weather monitoring through its Atmospheric Sounding System, which provides vertical profiles of temperature (40 levels from surface to ~ 70 km), humidity (21 levels from surface to ~ 15 km) and integrated ozone from surface to top of the atmosphere. The satellite also has a data relay transponder onboard which would collect the weather observations from automatic weather stations located at inaccessible area in desserts, mountains and water bodies. Meanwhile, the IMD and ISRO have already established over 1,800 data collection platforms at various remote places of India. Another key payload of this system is the search and rescue unit which will pick up distress beacons from users on land, sea and in air during emergencies. India’s neighbors and islands in Indian Ocean region could also get benefit from this system.


INSAT-3D is an advanced weather satellite configured with improved imaging System and Atmospheric Sounder. India being an agricultural economy has significant amount of dependence on weather conditions. Weather inputs play an important role for forecasting and monitoring the progress of Indian monsoon. India being a peninsula is regularly affected by tropical cyclonic storms particularly during summers and early winter period. The weather department has significant dependence on satellite imageries for this purpose.


In regards to natural disasters, India could be viewed as a victim of its geography. The Himalayan mountain range which is located at the northern and eastern parts of the country is prone to earthquakes, landslides, flash floods, glacier lake outburst floods (GLOFs), Artificial Glacier Lake Outburst (AGLO) and glacier melting. In recent past India has witnessed devastating natural disasters like tsunamis, earthquakes, cyclones and floods etc. Recently the Uttarakhand region in the northern parts of India had witnessed a major natural disaster. The flash floods following the 16-18 June, 2013 heavy rains had forced the Indian government to launch one of the biggest reliefs and rescue operation in recent times. This disaster had killed thousands and an estimated 100,000 people were rescued by the India’s security forces, civil rescue workers and disaster management agency. The mammoth physical effort put-up by these agencies was supported by appropriate weather nowcasting and short range forecasting.This became possible due to variety of factors including the actual inputs received from the disaster area about weather and topographic conductions, inputs received from radars and satellites and usage of Geographical Information Systems (GIS) tools.


Over last few years India has merged as new hub for making investments in the business sector globally. Various multinational agencies are found making increasing investments in various projects in India including infrastructure projects. For the execution of these projects timely and accurate weather inputs are essential. Water scarcity is rapidly becoming the cause of concern in various parts of India. For effective implementation of water resources management, meteorological inputs are essential. Tourism sector is another sector which is significantly dependent on climatic conditions. Particularly the increase in the aviation activity demands reliable and timely weather forecasts.


India and the subcontinent have already been witnessing severe climate change induced disasters and erratic weather phenomenon. To cope with climate change including above mentioned requirements, the launch of weather satellites INSAT-3D should be viewed as a timely and much needed step.

Author Note
Ajey Lele (Ph.D.) is Research Fellow at the Institute for Defence Studies and Analyses, New Delhi