Studies of the thermal regime of water in the unglaciated Arctic Fuglebekken catchment were carried out from 2005 to 2022 on Spitsbergen (Svalbard) using in-situ measurements and simulation results of two types of models.

The goal was to explain the variation of water temperature with an hourly step over the indicated period. For this purpose, two types of models were used: a stochastic transition function and supervised machine learning. Different sets of input variables needed to simulate hourly step water temperature were tested.

It was found that ground temperature at a depth of 20 cm and total solar radiation are the variables that explain most of the variation in water temperature. The developed models were used to reconstruct the thermal regime in the June-September period from 2005-2022 and to estimate changes. The results of both models show similar trends of change, an increase in water temperature throughout the summer period. The largest increase, about 6.0°C between 2005 and 2022, was recorded in the second half of June.

The results of the study demonstrate that the thermal regime of the Fuglebekken catchment is sensitive to ongoing climate change. The authors plan to extend their analysis with data from other rivers in the PSP Hornsund area.

We invite you to read the paper using the following link:
https://www.sciencedirect.com/science/article/pii/S0048969724014372?via%3Dihub