Articles | Volume 15, issue 17
Model description paper
 | Highlight paper
08 Sep 2022
Model description paper | Highlight paper |  | 08 Sep 2022

HORAYZON v1.2: an efficient and flexible ray-tracing algorithm to compute horizon and sky view factor

Christian R. Steger, Benjamin Steger, and Christoph Schär

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Executive editor
Finding the horizon is commonplace for humans, and evocative when imagining journeys on the coast, in the mountains, or in endless plains. This paper shows a way to optimize a machine's ability to complete the same task, with the goal of bettering our ability to understand nature and climate.
Short summary
Terrain horizon and sky view factor are crucial quantities for many geoscientific applications; e.g. they are used to account for effects of terrain on surface radiation in climate and land surface models. Because typical terrain horizon algorithms are inefficient for high-resolution (< 30 m) elevation data, we developed a new algorithm based on a ray-tracing library. A comparison with two conventional methods revealed both its high performance and its accuracy for complex terrain.