Introduction to development for practical applications of multi-satellite data including Geostationary Ocean Color Imager to maritime issues

Abstract

Geostationary Ocean Color Imager (GOCI) was serviced from April 2011 to March 2021. GOCI-II, in service since April 2021, produced tremendous outcomes in Korea in terms of data support for practical applications and scientific research. We are investigating eight application modules for practical use to maritime issues using various ocean monitoring satellite data, including GOCI, to provide products applicable to maritime information service organizations. The practical techniques we have chosen are to detect floating algae, marine fog, harmful algal blooms, fine aerosol particles, low sea surface salinity water, detect and forecast abnormal sea surface temperature, derive ocean water quality parameters, and primary productivity. Several practical candidate techniques are included. The application development process consists of three phases: performance targeting, development, and verification. Target performance for each technique is decided based on a user requirement survey and expert advice. We consider accuracy, target region, and temporal-spatial resolutions to cover specific issues from the user's point of view. We will improve the detection(prediction) accuracy over the performance of the GOCI output. Each practical application technique is established as an independent processing module. We prepare the algorithm verification procedure document to test the processing module and verify the result with verification data to meet the performance goal. A separate verification will be performed to increase the reliability of the module. We develop a prototype module and compare the results with high-resolution satellite data or reliable in-situ data. In the floating algae case, GOCI-based and OLI results are compared. While the targets of the hit rate and the false alarm rate are 80% and 20%, the verification results show the hit rate is 84.82%, and the false alarm rate is 0.1%. Comparisons will be made on techniques that have advanced a lot, such as marine fog, fine aerosol particles. Also, we are developing an integrated satellite information service system that incorporates eight processing modules and includes functions to display and analyze the satellite-derived products. We expect technology transfers to users for reliable and mature applications. These will contribute to societal benefits by adding multi-satellite-based information to the decision-making process.