The purpose of this study is to investigate variation in water export and instream temperatures throughout the open water season in a beaded Arctic stream, consisting of small pools connected by shallow chutes. The goals are to better understand heat and mass movement through these systems, how this may impact chemical and biological processes, and the resulting shifts with changes in climate. This is accomplished by first examining the extent and variability of water storage and export through qualitative analysis of observational data. Further, heat fate and transport is examined through development of an instream temperature model. The model formulation, a simple approach to model calibration and validation, and information regarding residence and characteristic times of different pool layers are presented. Using temperatures measured at high spatial resolution within the pools and surrounding bed sediments as well as other supporting data (e.g., instream flow, specific conductivity, weather data, and bathymetry), various types of storage within the pools, banks, and marshy areas within the riparian zone, including subsurface flow paths that connect the pools, were found. Additionally, data illustrated that some pools will stay stratified during higher flow periods under certain weather conditions. Through modeling efforts, the dominant heat sources were found to vary between stratified layers. It was also found that potential increases in thaw depths surrounding these pools can shift stratification and mixing patterns. These shifts can further influence mass export dynamics and instream water quality. Given the amount and different types of storage within these systems and the influence of stratification patterns on the residence times in the pools, Imnavait Basin and similar beaded Arctic watersheds will likely experience delayed export of nutrients that are limiting in most Arctic systems.

The hydrological regime in Arctic catchments is being altered as an effect of climate change. To be able to project future changes in Arctic hydrology and hydrogeology, the mechanisms and drivers affecting runoff generation needs to be understood. This thesis aims to investigate and compare rainfall-runoff processes in three hillslope subcatchments, one glacierized and one non-glacierized catchment, in the Arctic. By estimating catchment response parameters and using recession analysis it was found that soil layer extent, rather than catchment size, explained differences in catchment response. The character of the rainfall events was a dominant factor affecting catchment response in both the glacierized and non-glacierized catchment. Saturation excess overland flow was a runoff-generating process in all catchments. Furthermore, permafrost and glacier presence, as well as meltwater contribution to the streams, were suggested to result in a larger variability in catchment response and storage contribution along the hillslopes and the glacierized catchment. Meanwhile, the wetness of the non-glacierized catchment was suggested to influence the storage-discharge dynamics in the non-linearized catchment. Water height recession analysis was not considered reliable to characterize aquifer properties in the catchments. However, it was able to describe the changes in storage-discharge relations over time in Arctic catchments.