NASA Satellite Data Enhances Monsoon Forecasting Accuracy Across India: Study

Reported By Akshata Pawar
Pune, 17th June 2025: A new scientific study has confirmed that NASA’s latest satellite rainfall product, IMERG (Integrated Multi-satellitE Retrievals for GPM), offers significantly improved accuracy in estimating monsoon rainfall across India compared to the earlier TMPA algorithm. The findings could mark a major breakthrough in weather forecasting, agricultural planning, and flood preparedness.

Published in the Journal of the Indian Society of Remote Sensing, the study titled “Evaluation of IMERG and TMPA Precipitation Products Over India During Summer Monsoon Season Using IMD‑GIS Rainfall Data” was conducted by researchers M. Venkatrami Reddy and K. Niranjan Kumar. Using high-resolution rain gauge data from the India Meteorological Department (IMD), the researchers evaluated the performance of both satellite algorithms during the critical monsoon season from June to September.

Key Findings:
-Higher Accuracy: IMERG demonstrated significantly better agreement with IMD’s ground-based rainfall data, especially in topographically complex regions like the Western Ghats and Northeast India.
-Better Detection of Extremes: The algorithm more accurately detected both intense downpours and lighter rainfall events, crucial for flood alerts and farming decisions.
-Improved Spatial Consistency: IMERG showed reduced systematic bias across India’s diverse landscapes, from coastal belts to mountainous terrain.

Importance of this Study:
With over 70% of India’s annual rainfall occurring during the monsoon, reliable precipitation estimates are vital for:
-Timely flood forecasting
-Efficient irrigation and crop planning
-Water resource management across dams and reservoirs

“This advancement is critical for better monsoon monitoring and water resource management,” the researchers noted, adding that enhanced satellite detection tools like IMERG are especially relevant as climate change makes India’s monsoon patterns more erratic.

The study underscores the importance of incorporating IMERG data into India’s official weather forecasting and disaster preparedness systems, while also calling for further enhancements to improve the detection of light rainfall and short-duration precipitation events.