Geomorphological Characterization of Rivers Using Virtual Globes and Digital Elevation Data: A Case Study from the Naryn River in Kyrgyzstan

Abstract

In recent years, fluvial geomorphology included a range of new technologies for the characterization of riverine landscapes in the pool of methods. LIDAR, the analysis of drone imagery or satellite remote sensing improved the ability to analyze river systems in manifold ways. However, the high demand for (often expensive) data and processing skills limit the application commonly to smaller study reaches or to regions where data is already available. In contrast, a range of conceptual frameworks for the geomorphological characterization of river systems highlights the relevance of integrating the catchment scale context. Against this background, virtual globes such as Google Earth are cost-efficient alternatives as they make high resolution satellite imagery available almost worldwide. Merging the information mapped from virtual globes with digital elevation data allows the interpretation of riverscape attributes in the context of the longitudinal profile. In our study, we present the geomorphological mapping of the more than 600 km long Naryn River in Kyrgyzstan based on different virtual globes and the SRTM-1 digital elevation model. The experience from this mapping exercise suggests that the combination of virtual globe imagery and elevation data is a powerful and cost-efficient approach for river research and application in the context of data-scarce river corridors.