Abstract
Catalogs of atmospheric rivers (ARs) are vital resources to advance AR science. However, identification of ARs at a global scale comes along with substantial challenges caused by regionally and temporally varying weather systems. Most available AR catalogs have regional extent, although only global AR catalogs can record large-scale heterogeneities in AR transport. Here, we introduce the PIK Atmospheric River Trajectories (PIKART) catalog, a global and comprehensive compilation of AR activity covering 84 years (1940 to 2023) with a high spatiotemporal resolution of 0.5° and 6 hours. PIKART identifies ARs by exploiting their anomalous moisture transport characteristics and is, therefore, threshold-free. Moreover, it tracks ARs prioritizing large and strong features, and allowing for physically-sound temporal gaps, ultimately improving the representation of long-lived ARs. PIKART substantially extends the scope of previous catalogs by providing secondary AR properties such as a novel index of inland penetration, land-intersecting locations, and AR levels. Available as a compilation of AR conditions and AR trajectories, PIKART facilitates the study of ARs from both the Eulerian and Lagrangian perspective. As a first overview of the catalog’s scope, we use PIKART to reveal i) additional hotspots of AR activity, particularly in the tropics, ii) exposure to considerable AR impacts in less-studied continents (e.g., South/East Asia and Oceania), iii) inland penetration of ARs into less-studied regions (e.g., north-western Africa), and iv) a poleward shift of southern hemispheric ARs and a global intensification of AR moisture transport. The PIKART catalog constitutes a valuable resource for future studies in AR science.
