Fusion of Landsat 8 Operational LandImager and Geostationary Ocean Color Imager for hourly monitoring surface morphology of lake ice with high resolution in Chagan Lake of Northeast China

The surface morphology of lake ice remarkably changes under the combined influence of thermal and me-chanical forces. However, research on the surface morphol-ogy of lake ice and its interaction with climate is scarce. A large-scale linear structure has repeatedly appeared on satel-lite images of Chagan Lake in recent years. The Geostation-ary Ocean Color Imager (GOCI), with a 1 h revisit, and Land-sat 8 Operational Land Imager (OLI), with a spatial resolu-tion of 30 m, provide the possibility for the study of hourly changes in the large-scale linear structure. We merged the Landsat and GOCI images, using an Enhanced Spatial and Temporal Adaptive Reflectance Fusion Model (ESTARFM), and extracted the lengths and angles of the linear structure. We monitored the hourly changes in the surface morphol-ogy during the cold season from 2018 to 2019. The average length of the linear structure in the completely frozen period was 21141.57 +/- 68.36 m. The average azimuth angle was 335.48 +/- 0.23?, nearly perpendicular to the domain wind in winter. Through two field investigations during the two re-cent cold seasons, we verified the linear structure as being ice fractures and ridges. The evolution of surface morphology is closely associated with air temperature, wind, and shoreline geometry.