Atmospheric rivers (ARs) are crucial pathways for atmospheric moisture transport into, and within, the polar regions. ARs significantly impact the Arctic climate system by enhancing atmospheric heat and moisture transport and altering the local energy budget. The development of AR detection tools (ARDT) is critical, and yet challenging. While most ARDTs are designed for global and/or mid-latitude applications, there are some ARDTs that are specifically tailored for the polar regions. This study evaluates 11 ARDTs in the Arctic to assess their performance in representing atmospheric heat (represented by moist static energy, MSE) and moisture (integrated vapor transport, IVT) transport, as well as surface downward longwave radiation (LWD) impacts, spanning 2000 to 2019 using ERA5 reanalysis.

AR occurrence frequency in the Arctic varies widely, from less than 1% to over 13%, depending on the ARDT. This variability leads to differences in contributions to poleward atmospheric heat (< 1% - 33%) and moisture (<1% - 49%) transport. The highest AR frequency, and corresponding contributions to atmospheric heat and moisture transport, occurs over the Atlantic sector during non-summer seasons for most ARDTs. This region aligns with the primary poleward moisture pathway and the end of climatological mid-latitude storm tracks, highlighting strong connections between Arctic ARs and mid-latitude storms. ARs induce significant LWD anomalies, with the largest in winter and smallest in summer. Global ARDTs, which detect fewer ARs in the Arctic, show greater anomalies (>100 W m^-2 in higher Arctic), but their integrated contribution to seasonal climatological LWD is much smaller (<1%). In contrast, polar-specific ARDTs detect higher AR occurrences and account for 10-15% of seasonal LWD. This suggests that algorithms emphasizing extreme events with large LWD anomalies do not necessarily indicate a large overall radiative climate impact. This work advances the understanding of Arctic ARs, their effects on the climate system, and the variability in the results based on the selected ARDT.