Evaluating Atmospheric River Impacts on Energy and Moisture Transport in the Arctic Using Different Detection Algorithms

Journal Article · Sat Feb 28 00:00:00 EST 2026 · Journal of Geophysical Research (JGR): Atmospheres

DOI:https://doi.org/10.1029/2025jd043335· OSTI ID:3025712

Zhang, Chen; Cassano, John J; Seefeldt, Mark W; Tung, Wen‐wen; Mahesh, Ankur; Collins, William D

Abstract Atmospheric rivers (ARs) significantly impact the Arctic climate system by enhancing atmospheric heat and moisture transport and altering the local energy budget. Developing AR detection tools (ARDTs) is critical yet challenging. This study evaluates 12 ARDTs in the Arctic to assess their performance in representing atmospheric heat (represented by moist static energy) and moisture transport, as well as surface downward longwave radiation (LWD) and precipitation impacts, spanning 2000 to 2019 using ERA5 reanalysis. We find that 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 cyclones. ARs induce significant LWD anomalies, largest in winter, smallest in summer, and also substantially contribute to the seasonal precipitation. Global ARDTs detect fewer ARs with larger anomalies (>100 W m −2 in higher Arctic), but contribute <1% to seasonal climatological LWD and precipitation. In contrast, polar‐specific ARDTs detect higher AR occurrences and account for up to 16% of seasonal LWD and 41% precipitation. This suggests that algorithms emphasizing extreme events with large anomalies do not necessarily indicate a large climate radiative and precipitation impact. Plain Language Summary Atmospheric rivers (ARs) are long narrow filaments of intense water vapor transport in the lower atmosphere that play a significant role in the Arctic climate. They bring heat and moisture into the region, influencing the energy balance and potentially accelerating sea ice loss and Arctic warming. However, detecting ARs in the Arctic is challenging because most AR detection tools (ARDTs) are designed for global or mid‐latitudes, with few tailored for polar regions. This study evaluates 12 ARDTs to assess their ability to identify Arctic ARs and their contributions to heat, moisture transport, surface radiation, and precipitation impacts. Results show a wide range of AR detection frequencies, from less than 1% to over 13%, depending on the ARDT used. This variability significantly affects estimates of how much heat and moisture ARs transport into the Arctic. ARDTs designed/adapted for the Arctic detect more frequent ARs and show they contribute meaningfully to seasonal surface radiation and precipitation impacts. In contrast, global ARDTs, which focus on extreme moisture events in mid‐latitudes, detect fewer ARs with larger radiation and precipitation anomalies but have reduced cumulative climate effects. These results emphasize the limitations of using global ARDTs in the Arctic context and should be avoided. Key Points AR detection tools (ARDTs) vary widely, leading to differences in Arctic AR frequency and heat and moisture transport impacts Polar ARDTs detect more ARs, contributing up to 33% heat, 49% moisture transport, 16% surface longwave radiation, and 41% precipitation Global ARDTs focus on extreme events with large anomalies but contribute as low as 1% to heat, moisture, radiative and precipitation impacts

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: US Department of Energy; USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23), Climate and Environmental Sciences Division (SC-23.1 )
• Grant/Contract Number: AC02-05CH11231
• OSTI ID: 3025712
• Journal Information: Journal of Geophysical Research (JGR): Atmospheres, Journal Name: Journal of Geophysical Research (JGR): Atmospheres Journal Issue: 4 Vol. 131
• Country of Publication: United States
• Language: English