Moisture transport axes: a unifying definition for tropical moisture exports, atmospheric rivers, and warm moist intrusions

Spensberger, Clemens; Konstali, Kjersti; Spengler, Thomas

doi:https://doi.org/10.5194/wcd-6-431-2025

Articles | Volume 6, issue 2

https://doi.org/10.5194/wcd-6-431-2025

© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/wcd-6-431-2025

© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 6, issue 2

Research article

|

17 Apr 2025

Research article |

| 17 Apr 2025

Moisture transport axes: a unifying definition for tropical moisture exports, atmospheric rivers, and warm moist intrusions

Clemens Spensberger, Kjersti Konstali, and Thomas Spengler

Supplement

https://doi.org/10.5194/wcd-6-431-2025-supplement

Data sets

ARTMIP Tier 2 Catalogues ERA5 Reanalysis Atmospheric River Tracking Method Intercomparison Project https://doi.org/10.26024/rawv-yx53

ERA5 hourly data on pressure levels from 1940 to present Hans Hersbach et al. https://doi.org/10.24381/cds.bd0915c6

ERA5 hourly data on single levels from 1940 to present Hans Hersbach et al. https://doi.org/10.24381/cds.adbb2d47

ERA5 moisture transport axis detections Clemens Spensberger https://doi.org/10.11582/2024.00178

ERA5 normalised moisture transport axis detections Clemens Spensberger https://doi.org/10.11582/2025.00001

Model code and software

Dynlib: A library of diagnostics, feature detection algorithms, plotting and convenience functions for dynamic meteorology Clemens Spensberger https://doi.org/10.5281/zenodo.10471187

Short summary

The transport of moisture from warmer and moister to colder and drier regions mainly occurs in brief and narrow bursts. In the mid-latitudes, such bursts are generally referred to as atmospheric rivers; in the Arctic they are often referred to as warm moist intrusions. We introduce a new definition to identify such bursts which is based primarily on their elongated structure. With this more general definition, we show that bursts in moisture transport occur frequently across all climate zones.