Experimental Observation and Assessment of Yellow River Ice Conditions with UAV Remote Sensing System

Due to the geographical location and regional climate, ice jams occur in Yellow River and its tributaries almost every spring while river ice is thawing. Ice jams can cause embankment burst and severe flood resulting in great property damage and human casualty. Therefore, there is an urgent need to timely carry out observation of ice conditions and make risk assessment. Field observation is most reliable but usually too expensive and time-consuming, as combined with remote sensing techniques is a promising approach. Owing to the factors of timeliness, image resolution, human safety, and cost, satellite or manned aerial remote sensing cannot fully meet the requirements of ice jam observation. With the advantages of low cost, flexible launch and landing manners, safety, and hyperspatial image resolution, UAV remote sensing system seems more suitable for collection of ice jamimagery. In this paper, one Inner-Mongolia segment of Yellow River was chosen as the experimental area to demonstrate key technologies and specific procedures of observation and assessment of ice-jam with UAV system. UAV remote sensing system and its components were first introduced: The procedures of UAV operation and imagery acquisition were then illustrated. The methodologies of image preprocessing and ice information extraction were described in detail. Finally, the ice conditions were analyzed and assessed based on resulting panoramic imagery. Our experiment has proved the feasibility and effectiveness of applying the fixed-wing UAV system to rapid observation and risk assessment for ice-jam occurrence in Yellow River under the weather conditions of low temperature and strong wind.