Atmospheric Rivers Research and Applications

CW3E will work toward effective, efficient, integrated monitoring of the state of the atmosphere, ocean surface, and land surface and subsurface to support decision-makers and stakeholders, and to answer key research questions that will increase forecasting accuracy for high-impact events at all relevant lead times.

Key Objectives:

A C-130 “Hurricane Hunter” on an AR Recon mission.

  1. Produce scientific publications that further understanding of AR dynamics from micro to synoptic scales.
  2. Enhance global AR monitoring through a transformative modernization of atmospheric measurements over the Pacific, in order to improve predictability and understanding of ARs and associated impacts.
  3. Produce forecasting and decision support tools that support the needs of western U.S. forecasters, resource managers, and emergency managers.

Challenges and solutions:

Enhanced knowledge of AR dynamics at all scales is critical to predicting total precipitation, precipitation rates, temperature profiles, and wind strength. Microscale processes help determine the type and rate of precipitation, while mesoscale processes can affect precipitation totals by influencing vapor transport intensity and duration, as well as by producing lift. Larger synoptic-scale processes can influence the direction and storm track of ARs. CW3E uses a variety of observations and models to examine how these processes interact, which helps us better understand the fundamental characteristics of ARs, their predictability, and their importance to precipitation in the West.

CW3E is leading the collection, processing, and dissemination of crucial observations of ARs and their impacts. The void of data over the Pacific Ocean has been a consistent challenge—one that CW3E is filling through targeted observations at the ocean surface and in the atmosphere. Intensive monitoring after landfall provides data to evaluate the AR as it interacts with the land. Hydrologic observations of streams and soils before AR landfall are also important, as these conditions modulate impacts. Thus, a well-developed network to observe the full water cycle is essential to progress in AR science and better prediction of weather and water extremes.

As AR science produces new results, CW3E will incorporate these results into applications for forecasters and managers throughout the West. A previous example is the incorporation of AR direction into CW3E’s landfall tool. Possible future examples include tools associated with the Advanced Quantitative Precipitation Information (AQPI) radar system in the San Francisco Bay area.

For more information on ARs visit the AR FAQs.