Abstract:
Within the cryosphere, glacier-fed streams exhibit distinctive thermal regimes due to glacier melt influences; accordingly, these streams host a unique coldwater ecosystem. The role of water temperature as a driver of various intra-ecosystem processes is particularly significant in glacierized basins due to the strong coupling and high sensitivity between atmospheric and in-stream processes. In this paper, we review studies of the temperature characteristics in glacier-fed river streams, the influencing factors, and the response in aquatic ecosystems. Previous analyses have shown that glacial rivers are characterized by low temperatures and remarkable spatiotemporal temperature variations. Influencing factors in glacial rivers can be summarized in four major categories: heat transfer at the air-water interface, heat transfer at the water-channel interface, runoff components, and climate change and human activity. The response of a glacial river thermal regime to its physicochemical properties results in changes to the river water quality and thermo-hydrological fluxes. While the response of the aquatic ecosystem changes the distribution and structure of aquatic system with changing glacial stream temperature, once a certain threshold is exceeded, the change will be irreversible.