Positive surface air temperature trends in a subarctic region: Analyzing the changes in dominant periodic components and energy budget

Abstract

Over the past few decades, global warming has significantly impacted permafrost regions, reflecting the amplification in Arctic temperature changes. To better understand climate variability and the changes in permafrost regions, in this study, we examined the changes in the surface air temperature (SAT) in the Republic of Sakha (Yakutia, Russia) from 1971 to 2022. The data from 18 meteorological stations were considered to assess the SAT trends, percentage change (PC), and dominant periodic components across the region. Additionally, the trends of the snow depth (SD) and energy budget components (EBCs), including the net radiation (NR) and latent and sensible heat (LH and SH, respectively), were investigated to elucidate the possible reasons for the SAT trends. The results confirmed a significant increase in the SAT at all stations at both the monthly and seasonal timescales. The monthly SAT trends ranged from 0.002 °C/month to 0.007 °C/month, with considerable variations in the autumn and spring seasons. The dominant periodicity components that affected the SAT monthly trends were the 16- and 32-month across all the stations. For individual seasons, the 4- and 8-year periodic components were identified as the most dominant periodic components to affect the SAT, EBC, and SD trends. Our study can serve as a foundation for future investigations on the changes in dominant periodic components and energy budgets in subarctic regions due to global warming, thereby supporting the ongoing efforts toward climate change mitigation.