Prominent impacts of snow–hydrological processes on near-surface temperature variability over Western Siberia

Abstract

Snow–hydrological processes have a major contribution to climate variability over the northern latitudes. While previous studies have investigated the remote influence of atmospheric circulation on the Eurasian climate, the impacts of snow–hydrological processes on near-surface temperature over the snow-sensitive regions have not been fully understood and require further investigation. In the present study, we examined the role of snow–hydrological processes on near-surface temperature variability over the Eurasian continent during the period 1980–2020. Results from Liang–Kleeman information flow analysis revealed that a region of strong snow water equivalent–soil moisture–temperature coupling (called cold spot) is located over the Western Siberia in June, where fluctuations in snow water equivalent and soil moisture tend to modulate near-surface temperature significantly. A composite analysis indicated that a significant decrease (increase) in soil moisture by ∼ 12 % (∼10 %) in response to a decrease (increase) in snow water equivalent by ∼ 6 mm (∼5 mm) during June tends to enhance warm (cold) temperature anomalies over Western Siberia by ∼ 2–3 °C (∼2 °C) through the modulation of surface energy partitioning. In addition, persistent high (low) pressure anomalies, anticyclonic (cyclonic) circulation anomalies, and clear sky (cloudy) conditions associated with the so-called British–Baikal Corridor pattern further favour to maintain the extremely hot (cold) temperature conditions over Western Siberia through land–atmosphere feedback processes.