Understanding and tracking Atmospheric Rivers

Atmospheric rivers (ARs) are long, narrow, filamentary structures that transport substantial moisture poleward, typically out of the tropics and into higher latitudes. They are often associated with extratropical cyclones and are an important part of the hydrological cycle, synthesizing weather and climate. In regions such as the western U.S., ARs are the dominant phenomenon leading to extreme precipitation and damaging flooding, which can be either beneficial, lifting drought-stricken areas out of water deficits, or devasting, depending on antecedent land surface conditions and water sector preparedness.

NCAR’s CATALYST group (http://www.cgd.ucar.edu/projects/catalyst/) is working to understand these phenomena, and how they may change in a future climate, by co-leading ARTMIP, the Atmospheric River Tracking Method Intercomparsion Project (http://www.cgd.ucar.edu/projects/artmip). The goal of ARTMIP is to quantify and understand uncertainties in AR science, and specifically, to disentangle the many ways ARs are defined and identified in the research community.


  • Shields, et al. "Atmospheric River Tracking Method Intercomparison Project (ARTMIP): project goals and experimental design", Geosci. Model Dev., 11, 2455-2474, https://doi.org/10.5194/gmd-11-2455-2018, 2018.
  • Rutz et. al., "The Atmospheric River Tracking Method Intercomparison Project (ARTMIP): Quantifying Uncertainties in Atmospheric River Climatology", in final revisions, JGR-A, 2019.