Measured discharge, hydrochemical parameters and computed fluxes (DOC, DN, solutes, suspended sediment) of a small Low Arctic watershed on Herschel Island (2014-2016)

• Main Authors: Coch, Caroline, Lamoureux, Scott F, Knoblauch, Christian, Eischeid, Isabell, Fritz, Michael, Obu, Jaroslav, Lantuit, Hugues
• Format: Dataset
• Language: English
• Published: PANGAEA 2018
• Subjects: Automatic water sampler (ISCO 3700); AWI_PerDyn; AWS_ISCO; Herschel Island; Yukon Territory; Canada; Ice_Creek_West; Permafrost Research (Periglacial Dynamics) @ AWI; Arctic; Yukon; Climate change; Herschel; permafrost
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.888180; https://doi.org/10.1594/PANGAEA.888180

Coastal ecosystems in the Arctic are affected by climate change. As summer rainfall frequency and intensity are projected to increase in the future, more organic matter, nutrients and sediment could be mobilized and transported into the coastal nearshore zones. However, knowledge of current processes and future changes is limited. We investigated streamflow dynamics and the impacts of summer rainfall on lateral fluxes in a small coastal catchment on Herschel Island in the western Canadian Arctic. For the summer monitoring periods of 2014-16, mean dissolved organic matter (DOM) flux over 17 days amounted to 82.7 ± 30.7 kg km**-2 and mean total dissolved solids flux to 5252 ± 1224 kg km-2. Flux of suspended sediment (SS) were 7245 kg km**-2 in 2015, and 369 kg km**-2 in 2016. We found that 2.0 % of SS was composed of particulate organic carbon. Data and hysteresis analysis suggests a limited supply of sediments; their interannual variability is most likely caused by short-lived localized disturbances. In contrast, our results imply that DOC is widely available throughout the catchment and exhibits positive linear relationship with runoff. We hypothesize that increased projected rainfall in the future will result in a similar increase of DOC fluxes.