气候变化领域集成服务门户(CCPortal): Towards a webcam-based snow cover monitoring network: Methodology and evaluation

CCPortal

DOI	10.5194/tc-14-1409-2020
	Towards a webcam-based snow cover monitoring network: Methodology and evaluation
	Portenier C.; Hüsler F.; Härer S.; Wunderle S.
发表日期	2020
ISSN	19940416
起始页码	1409
结束页码	1423
卷号	14 期号:4
英文摘要	Snow cover variability has a significant impact on climate and the environment and is of great socioeconomic importance for the European Alps. Terrestrial photography offers a high potential to monitor snow cover variability, but its application is often limited to small catchment scales. Here, we present a semiautomatic procedure to derive snow cover maps from publicly available webcam images in the Swiss Alps and propose a procedure for the georectification and snow classification of such images. In order to avoid the effort of manually setting ground control points (GCPs) for each webcam, we implement a novel registration approach that automatically resolves camera parameters (camera orientation; principal point; field of view, FOV) by using an estimate of the webcams' positions and a high-resolution digital elevation model (DEM). Furthermore, we propose an automatic image-to-image alignment to correct small changes in camera orientation and compare and analyze two recent snow classification methods. The resulting snow cover maps indicate whether a DEM grid is snow-covered, snow-free, or not visible from webcams' positions. GCPs are used to evaluate our novel automatic image registration approach. The evaluation reveals a root mean square error (RMSE) of 14.1 m for standard lens webcams (FOV<48ĝˆ) and a RMSE of 36.3 m for wide-angle lens webcams (FOV≥48ĝˆ). In addition, we discuss projection uncertainties caused by the mapping of low-resolution webcam images onto the high-resolution DEM. Overall, our results highlight the potential of our method to build up a webcam-based snow cover monitoring network. © Author(s) 2020. This work is distributed under the Creative Commons Attribution 4.0 License.
英文关键词	climate effect; digital elevation model; environmental monitoring; Internet; mapping method; methodology; parameter estimation; photography; snow cover; Alps; Switzerland
语种	英语
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202183
作者单位	Institute of Geography and Oeschger, Centre for Climate Change Research, University of Bern, Bern, Switzerland; Federal Office for the Environment (FOEN), Ittigen, Switzerland; Professorship Ecoclimatology, Technical University of Munich, Freising, Germany
推荐引用方式 GB/T 7714	Portenier C.,Hüsler F.,Härer S.,et al. Towards a webcam-based snow cover monitoring network: Methodology and evaluation[J],2020,14(4).
APA	Portenier C.,Hüsler F.,Härer S.,&Wunderle S..(2020).Towards a webcam-based snow cover monitoring network: Methodology and evaluation.Cryosphere,14(4).
MLA	Portenier C.,et al."Towards a webcam-based snow cover monitoring network: Methodology and evaluation".Cryosphere 14.4(2020).