Monitoring 'Drought' with Satellites

Development of 'Hybrid' Technology for Satellite-Measured Soil Moisture Data
Overcoming Spatiotemporal Limitations Enables Near Real-Time Drought Monitoring

[Asia Economy Reporter Junho Hwang] A technology that can monitor drought in near real-time has been developed. This technology predicts the likelihood of drought occurrence by combining soil moisture levels observed by satellites with computer simulation data. The research team expects it to help predict crop yields and proactively identify the potential for large-scale wildfires.

Dr. Eun-Kyo Seo of the Department of Urban Environmental Engineering at Ulsan National Institute of Science and Technology (currently a researcher at George Mason University) and Professor Myung-In Lee's research team announced on the 28th that, together with NASA, they developed a technology that improves the accuracy of soil moisture information observed by satellites and rapidly processes large-scale global data to monitor drought in near real-time.

The research team enhanced the accuracy of soil moisture information by assimilating (data assimilation) satellite-observed soil moisture data with model simulation data. The model simulation comprehensively considers variables such as precipitation, radiation heat, surface temperature, and wind to provide information on the total soil moisture content of the Earth, including the root zone. By integrating this with locally observed soil moisture data from satellites, it is possible to predict soil moisture information over a wider area.

Dr. Eun-Kyo Seo, the first author, explained, "We used the 'Local Ensemble Transform Kalman Filtering technique' for data assimilation," adding, "This allows us to quickly and accurately find the optimal data 'mixing ratio' to produce highly accurate soil moisture information." Professor Myung-In Lee expressed hope, saying, "This research can be used not only for drought monitoring but also for developing technology to predict drought in the mid to long term."

The results of this study were recently published in the international journal in the field of remote sensing, Remote Sensing of Environment.

Performance Comparison of Soil Moisture Variables Produced by the Data Assimilation System