Drivers and projections of ice phenology in mountain lakes in the western United States

Timothy J Caldwell; Sudeep Chandra; Thomas Albright; Adrian Harpold; Thomas Dills; Jonathan Greenberg; Steven Sadro; Michael D. Dettinger

doi:10.1002/lno.11656

USGS · 70221833

Drivers and projections of ice phenology in mountain lakes in the western United States

Timothy J Caldwell·Sudeep Chandra·Thomas Albright·Adrian Harpold·Thomas Dills·Jonathan Greenberg·Steven Sadro·Michael D. Dettinger

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Abstract

Climate change is causing rapid warming and altered precipitation patterns in mountain watersheds, both of which influence the timing of ice breakup in mountain lakes. To enable predictions of ice breakup in the future, we analyzed a dataset of mountain lake ice breakup dates derived from remote sensing and historical downscaled climate data. We evaluated drivers of ice breakup, constructed a predictive statistical model, and developed projections of mountain lake ice breakup date with global climate models. Using Random Forest analysis, we determined that winter and spring cumulative snow fraction (portion of precipitation falling as snow) and air temperature are the strongest predictors of ice breakup on mountain lakes. Interactions between precipitation, cumulative winter air temperature and lake surface area indicate that shifts in air temperature and precipitation affect smaller lakes (< 2 km 2 ) more than larger lakes (> 2–10 km 2 ). A linear mixed effects model (RMSE of 18 d), applied with an ensemble of 15 global climate models, projected that end-of-century ice breakup in mountain lakes will be earlier by 25 ± 4 and 61 ± 5 (mean ± SE) days for representative concentration pathways 4.5 and 8.5, respectively.

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Limnology and Oceanography Article

Source-reported bounding extent: 35.47856499535729° to 49.01625665778159° latitude; -123.1787109375° to -116.114501953125° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Timothy J Caldwell, Sudeep Chandra, Thomas Albright, Adrian Harpold, Thomas Dills, Jonathan Greenberg, Steven Sadro, Michael D. Dettinger. 2020-11-27. Drivers and projections of ice phenology in mountain lakes in the western United States. https://doi.org/10.1002/lno.11656

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