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Title: Albedo change from snow algae blooms can contribute substantially to snow melt in the North Cascades, USA
Abstract Snow algae are ubiquitous in the Pacific Northwest cryosphere in the summer where snowmelt is an important contribution to regional watersheds. However, less attention has been given to biological impurities as drivers of snowmelt compared to inorganic light-absorbing particles. Here we map snow algae near Mt. Baker with a multispectral camera on an uncrewed aerial vehicle using (1) principal components and (2) spectral indexing. The two approaches are tested under differing bloom states and verified with coincident algal pigment and cell count data. During high bloom intensity we found an average instantaneous radiative forcing of 237 W m−2with a maximum of 360 W m−2. This translated to 1,508 ± 536 m3of melted snow water equivalent in the 0.1 km2basin. These results demonstrate snow algae contribute to snowmelt at mid-latitudes and the potential for uncrewed autonomous vehicles to map snow algae over expansive areas of the cryosphere.  more » « less
Award ID(s):
2046240
PAR ID:
10490587
Author(s) / Creator(s):
;
Publisher / Repository:
Nature Communications Earth and Environment
Date Published:
Journal Name:
Communications Earth & Environment
Volume:
4
Issue:
1
ISSN:
2662-4435
Subject(s) / Keyword(s):
Cryosphere snow algae albedo snowmelt radiative forcing UAVs multi-spectral imagery
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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