Nondispersive Drainage Direction Simulation Based on Flexible Triangular Facets

作者：Pengfei Wu, Jintao Liu, Xiaole Han, Zhongmin Liang, Yangyang Liu, Junyuan Fei · 发表于：Water Resources Research · 年份：2020 · DOI：10.1029/2019wr026507 · 被引用次数：7 · 研究领域：Hydrology and Watershed Management Studies、Flood Risk Assessment and Management、Cryospheric studies and observations

Abstract A new eight‐direction algorithm (iFAD8) for the simulation of drainage directions on grid digital elevation models (DEMs) is presented. In this algorithm, a flexible triangular facet construction technique (ND∞) is developed to provide local drainage directions ranging continuously from 0° to 360°. Subsequently, a flow aggregation technique using global deviations of local drainage directions is proposed to simplify the flow paths into a nondispersive format. Another algorithm (FAD8) accompanying the iFAD8 is also presented, which uses the D∞ directions as the local drainage directions. Then FAD8, iFAD8, and three existing algorithms are compared on 10 abstract terrains including nine basic terrains and a Himmelblau terrain. The algorithms are tested to reproduce exact slope lines and specific catchment areas derived from the terrain functions. The results show that iFAD8 has better performance than FAD8. Both iFAD8 and FAD8 outperform existing algorithms in most cases. The flow aggregation technique is shown to be an excellent choice for nondispersive drainage direction simulation based on infinite directions. The ND∞ direction based on flexible triangular facets is also an improvement to the local infinite direction of D∞. We conclude that the iFAD8 algorithm can provide better definitions of drainage directions.