Looking beyond wildlife: Using remote cameras to evaluate accuracy of gridded snow data

Alexej P.K. Siren; Marcelo Somos-Valenzuela; Catherine Callahan; Jillian R. Kilborn; Timothy Duclos; Cassie Tragert; Toni Lyn Morelli

doi:10.1002/rse2.85

USGS · 70211494

Looking beyond wildlife: Using remote cameras to evaluate accuracy of gridded snow data

Alexej P.K. Siren·Marcelo Somos-Valenzuela·Catherine Callahan·Jillian R. Kilborn·Timothy Duclos·Cassie Tragert·Toni Lyn Morelli

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Abstract

The use of remote cameras is widespread in wildlife ecology, yet few examples exist of their utility for collecting environmental data. We used a novel camera trap method to evaluate the accuracy of gridded snow data in a mountainous region of the northeastern US. We were specifically interested in assessing (1) how snow depth observations from remote cameras compare with gridded climate data, (2) the sources of error associated with the gridded data and (3) the influence of spatial sampling on bias. We compared daily observations recorded by remote cameras with Snow Data Assimilation System (SNODAS ) gridded predictions using data from three winters (2014–2016). Snow depth observations were correlated with SNODAS predictions for sites ( R 2 = 0.20) and regions ( R 2 = 0.16), yet we detected factors associated with SNODAS bias at both scales. Specifically, SNODAS underpredicted depths at high elevations, at sites with higher solar radiation, and within conifer‐dominated forest. Depths were most underpredicted at highest elevations, up to 44 and 26 cm on average at the site and region scales, respectively. Bias was greatest when predictions were lowest, occasionally predicting snow absence when depths were >100 cm at camera sites. We also detected breakdowns in accuracy when certain environmental conditions varied within the 1 km 2 SNODAS grid cells. For example, underprediction was greatest when the solar radiation values of camera stations increased relative to the mean of the SNODAS grid cells. This relationship was most prominent in mountainous regions, suggesting that factors which influence solar radiation (e.g. topographic complexity) contribute to SNODAS inaccuracy. We caution using gridded snow data for ecological studies when bias is unknown. We suggest increased sampling to adjust for errors associated with gridded data products that arise from factors, such as forest cover and topographic variability. Increasing resolution and accuracy of climate data will improve predictions of species’ responses to climate change.

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Remote Sensing in Ecology and Conservation Article

Source-reported bounding extent: 43.01268088642034° to 45.29421101337773° latitude; -72.432861328125° to -70.9222412109375° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

Alexej P.K. Siren, Marcelo Somos-Valenzuela, Catherine Callahan, Jillian R. Kilborn, Timothy Duclos, Cassie Tragert, Toni Lyn Morelli. 2018-06-11. Looking beyond wildlife: Using remote cameras to evaluate accuracy of gridded snow data. https://doi.org/10.1002/rse2.85

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