Climatological variations of moisture sources for precipitation of North Atlantic tropical cyclones linked to their tracks
Published in Atmospheric Research, 2023
Recommended citation: Pérez-Alarcón, A.; Coll-Hidalgo, P.; Fernández-Alvarez, J.C.; Trigo, R.M.; Nieto, R.; Gimeno, L. (2023). Climatological variations of moisture sources for precipitation of North Atlantic tropical cyclones linked to their tracks. Atmospheric Research, 290, 106778. https://doi.org/10.1016/j.atmosres.2023.106778
The tropical cyclones (TCs) trajectories are mainly controlled by the large-scale parameters related with the steering flow. We used the HURDAT2 database from 1980 to 2018 for grouping the tracks of TCs formed in the North Atlantic (NATL) main development region into straight moving (SM), recurving landfall (RCL) and recurving ocean (RCO). Based on this classification, we investigated the changes in the moisture sources’ contributions to the precipitation along the TCs trajectories for each track category by applying a Lagrangian moisture source diagnostic method to the air parcels pathways from the FLEXPART model. The highest moisture contribution occurred within 3-5° from the average TCs trajectories. The moisture supplied from the Gulf of Mexico represented 19.1% of humidity gained by SM but was negligible for recurving TCs. Likewise, the Caribbean Sea contributed 31.8% for SM, and its humidity support notably decreased for recurving storms to 0.9–8.3%. In addition, the moisture uptake from the tropical NATL was similar for all track types. The western NATL increased the moisture supply from 15.3% for SM to 31.1% for RCO and 42.6% for RCL, while the eastern subtropical NATL provided 3.1% of moisture to SM, 12.5% to RCL and 45.4% to RCO. It was also notable the moisture support from the terrestrial source southeastern United States (5.3%) for RCL tracks. Furthermore, we found that El Niño–Southern Oscillation, the North Atlantic Oscillation, the Atlantic Multidecadal Oscillation and the Atlantic Meridional Mode influence the moisture contributions variability from sources for each track type.