New Satellite Method Rivals NASA’s CERES for Radiation Measurement

A team of researchers from Sun Yat-sen University and the National Satellite Meteorological Center published a study in the Journal of Remote Sensing on April 1st, 2025. The study presents an advanced algorithm that utilizes data from the Fengyun-3F satellite's Earth Radiation Measurement-II (ERM-II) sensor.

The Earth's radiation budget, which balances incoming solar energy and outgoing radiation, plays a crucial role in regulating climate, ocean currents, and biological processes. Accurate assessment of shortwave radiation components is essential for climate models, but traditional methods face challenges due to atmospheric complexities and sensor limitations.

These challenges have led to the development of more precise and efficient algorithms that can improve radiation estimations under varying atmospheric conditions.

This new approach successfully measures radiation data under all-sky conditions, overcoming issues such as diverse scene types and atmospheric unpredictability. It uses a look-up table (LUT) structure that enables the simultaneous calculation of top-of-atmosphere (TOA) albedo, shortwave downward radiation (SWDR), and photosynthetically active radiation (PAR) with high accuracy.

The system achieves strong correlation coefficients—0.87 for TOA albedo, 0.89 for SWDR, and 0.83 for PAR—while eliminating the need for complex supplementary data. Its precision is comparable to NASA's CERES products and reduces bias in SWDR calculation, setting a new benchmark for satellite-based radiation measurement.

The team used MODTRAN 6, a radiative transfer model, to simulate various atmospheric and surface conditions, creating a reliable LUT for accurate estimations. The method was validated using real-world data from 21 ground stations and large simulated datasets.

The results showed strong consistency with radiative transfer simulations, with R² values of 0.98 for TOA albedo, 0.96 for SWDR, and 0.96 for PAR. Advanced atmospheric classification and correction methods were also applied to address long-standing issues, such as cloud-snow misclassification and adjacency effects.

This algorithm represents a significant step forward in satellite-based radiation monitoring. By enhancing the accuracy of shortwave radiation estimates, we can improve our understanding of climate dynamics and provide crucial data for environmental decision-making. The implications for climate modeling, solar energy forecasting, and even agricultural applications are profound.

Dr. Tianxing Wang, Study Lead Researcher, Sun Yat-sen University

Beyond its impact on climate research, the new algorithm has significant potential for practical applications. More accurate radiation data could refine climate models, improve solar energy predictions, and support global climate change efforts.

Future work will focus on enhancing the algorithm's performance on high-reflectance surfaces and expanding its ability to differentiate between direct and diffuse radiation components. As the need for precise climate monitoring increases, this technology could transform how scientists measure and understand the Earth's radiation budget.

Journal Reference:

‌Yan, X., et al. (2025). The First Estimation of Multiple Shortwave Radiation Components from the Chinese New-Generation Broadband Sensor (Earth Radiation Measurement-II) Onboard Fengyun-3F Satellite. Journal of Remote Sensing. doi.org/10.34133/remotesensing.0486.