The Indian Space Research Organisation (Isro) has told the Commission for Air Quality Management in NCR and Adjoining Areas (CAQM) that farm fire data currently extracted from different satellites may not be present ground reality, and that it will develop in-house algorithms to analyse foreign satellite data to get accurate counts.
The space agency’s response to farm fires in the country was shared by CAQM with the Supreme Court in an affidavit Thursday after the apex court’s latest directions to procure data from geostationary satellites instead of from Nasa’s polar-orbiting satellites and to make it available for states to take prompt action.
On Monday, the Supreme Court was informed that there could be an undercount in the data on farm fires collected through the polar-orbiting Nasa satellite. A senior Nasa scientist’s recent claim on X that farmers are evading satellite detection due to its limited capacity to capture farm fire events between 10.30 am and 1.30 pm was brought to the attention of the apex body. The apex court was also informed that data from GEO-KOMPSAT 2A, the geostationary Korean satellite, had picked up fires after Nasa’s polar-orbiting had passed, raising questions over the count of farm fires.
In its letter to CAQM, Isro has said the Supreme Court’s concerns are valid, and that efforts are on to get an accurate estimate. The pollution control and monitoring body has submitted Isro’s response in the affidavit it submitted to the Supreme Court.
Speaking about the different satellites available in the afternoon or evening, the affidavit said INSAT-3DR, Geo-Kompsat 2-AMI, Meteosat-9, Feng Yun-4A/4B, HIMAWARI-8 from India, South Korea, European Union, China and Japan, respectively, are inadequate to give an accurate farm fire count.
Government agencies, including the Indian Agricultural Research Institute (IARI) and various state remote sensing centres, at present, use data from the Nasa satellites Suomi NPP, Terra MODIS, and Aqua MODIS.
However, Isro said using data from the available satellites is still insufficient. Coarse-resolution, the need for the development of specific algorithms to process the raw data, lack of validation over India, and lack of evaluation of the accuracy of the data and its analysis were cited as as reasons by the space agency for its reluctance to use the satellites’ data.
“Data processing and fire detection algorithms for foreign geostationary satellite data are developed by respective agencies and are not validated over India…The active fire products from current geostationary platforms are sub-optimal for operational use for crop fire monitoring over Punjab and Haryana regions,” said Isro.
It said INSAT-3DR, the Indian satellite with a 30-minute observation frequency, cannot be used to accurately detect farm fire counts yet, because the images generated by it are of coarser resolution compared to Aqua MODIS. The number of fires, hence, detected using this satellite is far less, especially in Punjab and Haryana. Isro said it may upgrade the fire algorithms of the latest INSAT-3DS within six weeks.
The space agency has said it will complete the data evaluation of Meteosat-9 and GK2 satellites in a month, and that it is yet to evaluate the usability of data set from another two sets of satellites (GK-2 and FY-2G/2H satellites) over the Indian region.
“In-house development of algorithms for analysing the satellite data from foreign satellites for fire products generation and validation over Area of Interest requires considerable efforts. However, ISRO will continue to work on it,” the space agency said.
