Multi-year, spatially extensive, watershed scale synoptic stream chemistry and water quality conditions for six permafrost-underlain Arctic watersheds

Abstract. Repeated sampling of spatially distributed river chemistry can be used to assess the location, scale, and stability of carbon and nutrient contributions to watershed-scale exports. Here, we provide a comprehensive set of water chemistry measurements and secondary ecosystem metrics describing the biogeochemical conditions of permafrost-affected Arctic watershed networks. These data were collected in watershed-wide repeated synoptic campaigns across six rivers across northern Alaska. Three watersheds are associated with the Arctic Long-Term Ecological Research (ARC LTER) site at Toolik Field Station (TFS), which were sampled seasonally each June and August from 2016 to 2018. Three watersheds were associated with the National Park Service (NPS) of Alaska and the US. Geological Survey (USGS), and were sampled annually from 2015 to 2019. Extensive water chemistry characterization included carbon species, dissolved nutrients, and anions and cations. The objective of the sampling designs and data acquisition was to generate a dataset to support the estimation of ecosystem metrics that describe the dominant location, scale, and overall stability of ecosystem processes in the Arctic. These metrics are: (1) subcatchment leverage, (2) variance collapse, and (3) spatial stability. Both water chemistry concentrations and secondary metrics are available at the National Park Service Integrated Resource Management Application portal ( https://doi.org/10.5066/P9SBK2DZ ) and within the Environmental Data Initiative LTER Data Portal ( https://doi.org/10.6073/pasta/258a44fb9055163dd4dd4371b9dce945 ).