Summary: | This study examines the dynamics of instream temperatures in Imnavait Creek, a beaded Arctic stream consisting of small pools connected by shallow chutes located north of the Brooks Range in Alaska. High resolution temperature data were collected vertically within the water column of two small pools and surrounding bed sediments during stratified conditions. These temperature and other supporting data (e.g., instream flow, weather data, and bathymetry) have been used to investigate dominant heat sources and sinks through the development of an instream temperature model. This model includes advective, surface, and bed conduction fluxes, simplified vertical exchange between stratified layers, and attenuation of shortwave radiation within a pool. We present the model formulation, data collection methods used in support of model development and population, and the approach to model calibration and validation. We found that the dominant heat sources vary between stratified layers and, through some simple model scenarios, that potential increases in thaw depths surrounding these pools can shift stratification and mixing patterns. This shift results in influences on instream temperatures and nutrient export dynamics.
|