A Case Study of the Physical Processes Associated with the Atmospheric River Initial-Condition Sensitivity from an Adjoint Model
Abstract
Analysis of a strong landfalling atmospheric river is presented that compares the evolution of a control simulation with that of an adjoint-derived perturbed simulation using the Coupled Ocean–Atmosphere Mesoscale Prediction System. The initial-condition sensitivities are optimized for all state variables to maximize the accumulated precipitation within the majority of California. The water vapor transport is found to be substantially enhanced at the California coast in the perturbed simulation during the time of peak precipitation, demonstrating a strengthened role of the orographic precipitation forcing. Similarly, moisture convergence and vertical velocities derived from the transverse circulation are found to be substantially enhanced during the time of peak precipitation, also demonstrating a strengthened role of the dynamic component of the precipitation.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 01, 2020
- Source ID
- 10.1175/jas-d-19-0155.1
Entities
People
- A. Michaelis
- Carolyn A. Reynolds
- F. Martin Ralph
- James D. Doyle
- Joel R. Norris
- Reuben Demirdjian
Organizations
- United States Army Corps of Engineers
- United States Naval Research Laboratory
- University of California