Quantifying snow controls on vegetation greenness

• DOI: 10.1002/ecs2.2309
• Publication Date: 2018-06-26T17:35:10Z
• Authors: Stine Højlund Ped...; Glen E. Liston; Mikkel P. Tamstorf; Jakob Abermann; Magnus Lund; Niels Martin Schmidt
• Keywords: Snowmelt; Elevation (ballistics)

Abstract Snow is a key driver for biotic processes in Arctic ecosystems. Yet, quantifying relationships between snow metrics and biological components challenging due to lack of temporally spatially distributed observations at ecologically relevant scales resolutions. In this study, we quantified snow, air temperature, vegetation greenness (using annual maximum normalized difference index [Max NDVI ] its timing _ DOY ]) from ground‐based remote‐sensing observations, combination with physically based models, across heterogeneous landscape high‐Arctic, northeast Greenland region. Across the 98‐km distance Ice Sheet (Gr IS ) coast, significant inland–coast gradients winter precipitation pre‐melt snow‐water‐equivalent [ SWE ]), snowmelt snow‐free day year [SnowFree_ ]). Near mean temperature was 4.5°C lower, 0.3 m greater, SnowFree_ 37 d later, than near Gr . The regional continentality gradient eight times stronger south‐to‐north air–temperature along east coast. strong gradient, greening‐up period (SnowFree_ ‐Max varied by 24–57 d. We non‐linear characteristics Max , growing degree‐days‐sums during (Greening_ GDD 16‐yr study (2000–2015). These demonstrated that metrics, both were more important drivers Greening_ within seasonally snow‐covered methodologies provided data are applicable any snow‐ vegetation‐covered area on Earth.