- 1British Antarctic Survey, Cambridge, UK.
- 2School of Earth and Environment, University of Leeds, Leeds, UK.
- 3Application Laboratory, Japan Agency for Marine-Earth Science and Technology, Yokohama, Japan.
- 4College of Arts and Sciences, J. F. Oberlin University, Tokyo, Japan.
- 5School of Geosciences, University of Edinburgh, Edinburgh, UK.
In recent decades, the Arctic has warmed nearly four times faster than the global average, undergoing profound changes as a result. A key factor in this accelerated warming is the meridional transport of atmospheric water vapour. Particularly, intense intrusions of moisture and heat, so-called atmospheric rivers (ARs), are rare phenomena to reach the high latitudes, but can have severe impacts on the Arctic environment.
In this study, we examine an AR pair in April 2020 using a combination of Eulerian and Lagrangian methods alongside observational data from Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition. The event consisted of two distinct ARs that followed separate pathways - one across Siberia and the other across the Atlantic - before converging in the central Arctic within the span of one week. Large-scale atmospheric circulation patterns associated with these ARs show a combination of low and high pressure systems on the flanks of the ARs, channelling moisture and heat northward. Notably, our results show that the Siberian AR was linked to extreme heat anomalies, whereas the Atlantic AR primarily transported abundant moisture.
Backward air parcel trajectories calculated using LAGRANTO provide new insights into the complex dynamics of Arctic ARs, revealing details of their distinct pathways and moisture source regions. Analysis of these trajectories also uncovers a strong connection between the observed sea ice melt in the Barents-Kara Sea and the interaction of an AR with the ice edge, underscoring the significant influence of ARs on the Arctic climate system.
How to cite: Aviles Podgurski, L. E., Martineau, P., Lu, H., Yamamoto, A., Phillips, T., Bracegirdle, T., Maycock, A. C., Orr, A., Fleming, A., Hogg, A. E., and Muszynski, G.: Pathways of Atmospheric Rivers in the Arctic: Dynamics, Moisture Transport, and Impacts on Sea Ice during April 2020, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-15984, https://doi.org/10.5194/egusphere-egu25-15984, 2025.