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Ralph, MF, Wilson AM, Shulgina T, Kawzenuk B, Sellars S, Rutz JJ, Lamjiri MA, Barnes EA, Gershunov A, Guan B, Nardi KM, Osborne T, Wick GA.  2018.  ARTMIP-Early start comparison of atmospheric river detection tools: How many atmospheric rivers hit northern California’s Russian River Watershed? Climate Dynamics.  
Shields, CA, Rutz JJ, Leung L-Y, Ralph FM, Wehner M, Kawzenuk B, Lora JM, McClenny E, Osborne T, Payne AE, Ullrich P, Gershunov A, Goldenson N, Guan B, Qian Y, Ramos AM, Sarangi C, Sellars S, Gorodetskaya I, Kashinath K, Kurlin V, Mahoney K, Muszynski G, Pierce R, Subramanian AC, Tome R, Waliser D, Walton D, Wick G, Wilson AM, Lavers D, Prabhat, Collow A, Krishnan H, Magnusdottir G, Nguyen P.  2018.  Atmospheric River Tracking Method Intercomparison Project (ARTMIP): Project goals and experimental design. Geoscientific Model Development. 11:2455-2474.  
Wilson, AM, Barros AP.  2017.  Orographic land-atmosphere interactions and the diurnal cycle of low-level clouds and fog. Journal of Hydrometeorology. 18:1513-1533.   10.1175/jhm-d-16-0186.1   AbstractWebsite

Previous work illuminated landform controls on moisture convergence in the southern Appalachian Mountains (SAM) promoting heterogeneity in the vertical structure of low-level clouds (LLC) and seeder-feeder interactions (SFI) that significantly impact warm season precipitation. Here, the focus is on elucidating orographic land-atmosphere interactions associated with the observed diurnal cycle of LLC and fog in the region. Three distinct hydrometeorological regimes during the Integrated Precipitation and Hydrology Experiment (IPHEx) are examined using the Weather Research and Forecasting Model. Sensitivity to the choice of planetary boundary layer parameterization was investigated in the light of IPHEx observations. Simulations using the Mellor-Yamada-Nakanishi-Niino scheme exhibit LLC and fog patterns most consistent with observations, albeit without capturing SFI. Independently of synoptic regime, the simulations reveal two distinct modes of orographic controls on atmospheric moisture convergence patterns that explain the diurnal cycle of LLC and fog. First, a stationary nocturnal mode at the meso-alpha scale associated with an extended flow separation zone supports low-level pooling and trapping of cold, moist, stable air in the inner mountain on the lee side of the western topographic divide. Second, a dynamic daytime mode that results from the coorganization of ridge-valley circulations at the meso-gamma scale and Rayleigh-Benard convection at the meso-beta scale is associated with widespread low-level instability below the envelope orography. Orographic decoupling results in the formation of a shallow stagnation zone between the western and eastern topographic divides at night that contracts westward during daytime. Predominantly easterly and southeasterly low-level moisture convergence patterns support early afternoon LLC formation in the inner SAM.

Cannon, F, Ralph FM, Wilson AM, Lettenmaier DP.  2017.  GPM satellite radar measurements of precipitation and freezing level in atmospheric rivers: Comparison with ground-based radars and reanalyses. Journal of Geophysical Research: Atmospheres.   10.1002/2017JD027355  
Williams, CR, Bringi VN, Carey L, Chandrasekar V, Gatlin P, Haddad ZS, Munchak SJ, Petersen WA, Meneghini R, Nesbitt SW, Tanelli S, Tokay A, Wilson A, Wolff D.  2014.  Describing the shape of raindrop size distributions using uncorrelated raindrop mass spectrum parameters. Journal of Applied Meteorology and Climatology. 53:1282-1296.