Description:
Rising global air temperatures are altering thermal regimes of streams
with major implications for physical, chemical and biological processes
(Hannah & Garner, 2015; Michel et al., 2022; Van Vliet & Zwolsman,
2008) Stream water temperature increases in high latitude regions are
more pronounced and rapid than anywhere else in the world (Post et al.,
2019), hence thermal regimes in polar streams are currently undergoing
rapid perturbations that require urgent study (Blaen et al., 2013;
Docherty et al., 2019; Park et al., 2017).
Technological advances in high-resolution monitoring offer tools to
improve processes understanding, feed hydrological-thermal models and
guide more targeted management strategies (Ouellet et al., 2020). The
development of Distributed Temperature Sensing (DTS) allows
high-resolution spatial (centimeter to meter scale) and temporal
(minutes to hours) continuous measurement of water temperature to enable
identification of patterns and processes at finer-scales than possible
previously (Matheswaran et al., 2014; Mohamed et al., 2021). However,
the use of DTS to explore in-stream temperature dynamics in
high-latitude regions over seasonal scales has been poorly documented to
date. Ploum et al. (2018) visualized DTS data in a boreal stream, where
the stream thermal regime was heavily influenced by an upstream lake. In
this article, for the first time, we visualize spatially resolved DTS
measurements of water temperature changes across the melt season in a
subarctic stream.