How INSAT Analysis Weather

Source: The post how INSAT system help in weather analysis has been created, based on the article “How satellites track the weather” published in “The Hindu” on 19th January 2024.

UPSC Syllabus Topic: GS paper 3- Science and Technology- Awareness in the fields of Space.

News: The article discusses how India’s INSAT satellites, including INSAT 3D and 3DR, help in weather forecasting. It explains how these satellites use different wavelengths to analyze clouds, snow, and other weather phenomena, and mentions upcoming satellite launches by India for enhanced weather monitoring. How INSAT Analysis Weather?

How Indian National Satellite (INSAT) System Help in Weather Analysis?

Advanced Imaging: INSAT satellites like 3D and 3DR use red-green-blue (RGB) imagers. These help in identifying different weather phenomena by analyzing solar reflectance and brightness temperature at various wavelengths.

INSAT 3D and 3DR’s strategic geostationary orbits ensure consistent monitoring over India, crucial for real-time weather analysis.

Day and Night Monitoring: With ‘day microphysics’ and ‘night microphysics’ components, these satellites effectively track weather changes both during day and night. This dual capability allows for more comprehensive monitoring.

Snow and Cloud Differentiation: The satellites differentiate between snow and clouds by their reflectance in different parts of the spectrum, crucial for accurate weather predictions.

Enhanced Weather Predictions: By combining day and night data, scientists can track cyclone formation and thunderstorm predictions, enhancing early warning systems.

Advanced Radiometers: Upgraded radiometers on satellites like 3DR provide better spatial resolution and functionality compared to earlier models like Kalpana 1 and INSAT 3A.

Atmospheric Sounders: These measure temperature, humidity, and water vapor, providing detailed atmospheric profiles essential for weather analysis.

Continual Improvement: Each new satellite in the series offers improved technology, like INSAT 3DR’s upgraded VHRR, sounder, and additional transponders, enhancing India’s weather monitoring capabilities.

How Satellites Analysis Color and Snow

Color Determination: Satellites like INSAT 3D use RGB imaging; colors depend on solar reflectance and brightness temperature. For instance, the strength of visible, shortwave infrared, and thermal infrared signals determine the amounts of green, red, and blue colors.

Tracking Snow: Snow has a unique signature. It reflects similarly to clouds in the visible spectrum but absorbs shortwave infrared radiation strongly. This absorption weakens the red component in the RGB scheme, allowing satellites to differentiate snow from clouds.

Type of Weather Satellites India have

Kalpana 1: Launched in 2002, was positioned in a geostationary orbit. It was equipped with an early version of the Very High-Resolution Radiometer (VHRR) and a data-relay transponder. It was deactivated in September 2017 after 15 years of service.

INSAT 3A: Launched in 2003, it carried a three-channel VHRR for meteorological observations with different resolutions for visible, thermal infrared, and water vapor bands.

INSAT 3D and 3DR: Both are stationed in geostationary orbits, at 82 degrees and 74 degrees east longitudes respectively. These satellites use upgraded VHRRs for improved spatial resolution and functionality. They also carry atmospheric sounders for measuring temperature, humidity, and water vapor.

Upcoming INSAT 3DS: Scheduled for launch in February 2024 by the Indian Space Research Organisation using the GSLV Mk II launch vehicle. The “3DS” in its name stands for “3D second repeat”, indicating it’s a subsequent iteration following the INSAT 3D and 3DR series.

Question for practice:

Examine how INSAT satellites, such as INSAT 3D and 3DR, contribute to India’s weather forecasting capabilities.