INSAT-3DS.
Live geostationary imagery from ISRO's latest meteorological satellite. Continuous scans every 15 minutes at 82°E — capturing what polar satellites miss.
How We Derive Real-Time AQI From ISRO Satellites.
While polar satellites (NASA MODIS / ESA Sentinel) only pass India twice a day, INSAT-3DS scans every 15–30 minutes. We invert optical depth into ground particulate concentrations using live boundary layer meteorology.
Every 30 minutes, ISRO MOSDAC publishes L2G AOD previews. We sample the exact equirectangular pixel at each monitoring centroid and reverse-match against the published MOSDAC color LUT.
Column AOD represents total sky particulates. Inverting to ground concentration requires dividing by the Planetary Boundary Layer Height (PBLH) and correcting for aerosol humidity swelling f(RH).
The resulting surface PM2.5 (µg/m³) is mapped through official CPCB piecewise linear breakpoints (Good: 0–30, Moderate: 61–90, Poor: 91–120, Very Poor: 121–250, Severe: 250+).
The Polar Blind Spot.
NASA polar satellites (MODIS/VIIRS) pass India at ~1:30 PM — missing the dusk biomass burning window. INSAT's geostationary orbit captures continuously.
Sentinel-5P & MODIS Cross-Calibration.
While ISRO INSAT-3DR provides continuous 15-minute cadence, Google Earth Engine serves as the high-resolution optical anchor, cross-calibrating thermal infrared channels using Copernicus Sentinel-5P TROPOMI Level-3 products.