Diagnosis of an Intense Atmospheric River Impacting the Pacific Northwest: Storm Summary and Offshore Vertical Structure Observed with COSMIC Satellite Retrievals

Abstract This study uses the new satellite-based Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) mission to retrieve tropospheric profiles of temperature and moisture over the data-sparse eastern Pacific Ocean. The COSMIC retrievals, which employ a global positioning system radio occultation technique combined with “first-guess” information from numerical weather prediction model analyses, are evaluated through the diagnosis of an intense atmospheric river (AR; i.e., a narrow plume of strong water vapor flux) that devastated the Pacific Northwest with flooding rains in early November 2006. A detailed analysis of this AR is presented first using conventional datasets and highlights the fact that ARs are critical contributors to West Coast extreme precipitation and flooding events. Then, the COSMIC evaluation is provided. Offshore composite COSMIC soundings north of, within, and south of this AR exhibited vertical structures that are meteorologically consistent with satellit...

[1]  Ying-Hwa Kuo,et al.  Satellite constellation monitors global and space weather , 2006 .

[2]  F. Martin Ralph,et al.  An Automated Brightband Height Detection Algorithm for Use with Doppler Radar Spectral Moments , 2002 .

[3]  P. Knippertz.  Tropical-extratropical interactions related to upper-level troughs at low latitudes , 2007 .

[4]  P. Neiman,et al.  The statistical relationship between upslope flow and rainfall in California's coastal mountains: Observations during CALJET , 2002 .

[5]  H. S. Muench,et al.  Observation of a Cold Front With Rope Cloud , 1985 .

[6]  R. Rotunno,et al.  Mechanisms of Intense Alpine Rainfall , 2001 .

[7]  J. Schofield,et al.  Observing Earth's atmosphere with radio occultation measurements using the Global Positioning System , 1997 .

[8]  Toby N. Carlson,et al.  Mid-Latitude Weather Systems , 1991 .

[9]  M. Falvey,et al.  Wintertime Precipitation Episodes in Central Chile: Associated Meteorological Conditions and Orographic Influences , 2007 .

[10]  Ying-Hwa Kuo,et al.  Intercomparison of integrated water vapor retrievals from SSM/I and COSMIC , 2008 .

[11]  M. Dettinger,et al.  Flooding on California's Russian River: Role of atmospheric rivers , 2006 .

[12]  Richard E. Carbone,et al.  Characteristics through the Melting Layer of Stratiform Clouds. , 1984 .

[13]  W. Emery,et al.  Atmospheric water vapour over oceans from SSM/I measurements , 1990 .

[14]  M. Gorbunov,et al.  Comparative analysis of radio occultation processing approaches based on Fourier integral operators , 2004 .

[15]  J. Bao,et al.  Interpretation of Enhanced Integrated Water Vapor Bands Associated with Extratropical Cyclones: Their Formation and Connection to Tropical Moisture , 2006 .

[16]  Rolf König,et al.  Atmosphere sounding by GPS radio occultation: First results from CHAMP , 2001 .

[17]  Christian Rocken,et al.  COSMIC System Description , 2000 .

[18]  F. Martin Ralph,et al.  Meteorological Characteristics and Overland Precipitation Impacts of Atmospheric Rivers Affecting the West Coast of North America Based on Eight Years of SSM/I Satellite Observations , 2008 .

[19]  M. Watkins,et al.  The gravity recovery and climate experiment: Mission overview and early results , 2004 .

[20]  J. Lundquist,et al.  Rain versus Snow in the Sierra Nevada, California: Comparing Doppler Profiling Radar and Surface Observations of Melting Level , 2008 .

[21]  James P. Hollinger,et al.  SSM/I instrument evaluation , 1990 .

[22]  R. Reynolds,et al.  The NCEP/NCAR 40-Year Reanalysis Project , 1996, Renewable Energy.

[23]  D. Cayan,et al.  Precipitation structure in the Sierra Nevada of California during winter , 1999 .

[24]  D. Durran,et al.  On the Effects of Moisture on the Brunt-Väisälä Frequency. , 1982 .

[25]  B. Chao,et al.  A Constellation of Microsatellites Promises to Help in a Range of Geoscience Research , 1999 .

[26]  Roy Rasmussen,et al.  Improvement of Microphysical Parameterization through Observational Verification Experiment , 2003 .

[27]  Martyn P. Clark,et al.  Rain-on-Snow Events in the Western United States , 2007 .

[28]  Christian Rocken,et al.  The COSMIC/FORMOSAT-3 Mission: Early Results , 2008 .

[29]  F. Martin Ralph,et al.  Improving Short-Term (0–48 h) Cool-Season Quantitative Precipitation Forecasting: Recommendations from a USWRP Workshop , 2005 .

[30]  Ying-Hwa Kuo,et al.  Assimilation of GPS radio occultation data for numerical weather prediction , 2000 .

[31]  J. O. Rhea.  Orographic Precipitation Model for Hydrometeorological Use. , 1977 .

[32]  Yong Zhu,et al.  A Proposed Algorithm for Moisture Fluxes from Atmospheric Rivers , 1998 .

[33]  G. Wick,et al.  Wintertime Nonbrightband Rain in California and Oregon during CALJET and PACJET: Geographic, Interannual, and Synoptic Variability , 2005 .

[34]  R. E. Hart,et al.  Use of Normalized Anomaly Fields to Anticipate Extreme Rainfall in the Mountains of Northern California , 2008 .

[35]  G. Kiladis.  Observations of Rossby waves linked to convection over the eastern tropical Pacific , 1998 .

[36]  F. Martin Ralph,et al.  Dropsonde Observations in Low-Level Jets over the Northeastern Pacific Ocean from CALJET-1998 and PACJET-2001: Mean Vertical-Profile and Atmospheric-River Characteristics , 2005 .

[37]  R. Meentemeyer,et al.  Climatologically Aided Mapping of Daily Precipitation and Temperature , 2005 .

[38]  N. Bond,et al.  Research aircraft observations of the mesoscale and microscale structure of a cold front over the eastern Pacific Ocean , 1991 .

[39]  Ronald B. Smith.  The Influence of Mountains on the Atmosphere , 1979 .

[40]  Ying-Hwa Kuo,et al.  Monitoring the atmospheric boundary layer by GPS radio occultation signals recorded in the open‐loop mode , 2006 .

[41]  C. Daly,et al.  A Statistical-Topographic Model for Mapping Climatological Precipitation over Mountainous Terrain , 1994 .

[42]  A. Stohl,et al.  Remote sources of water vapor forming precipitation on the Norwegian west coast at 60°N–a tale of hurricanes and an atmospheric river , 2008 .

[43]  Christian Rocken,et al.  Inversion and error estimation of GPS radio occultation Data , 2004 .

[44]  F. Martin Ralph,et al.  The Impact of a Prominent Rain Shadow on Flooding in California's Santa Cruz Mountains: A CALJET Case Study , 2002 .

[45]  Keith A. Browning,et al.  Organization of Clouds and Precipitation in Extratropical Cyclones , 1990 .

[46]  J. Peixoto,et al.  Physics of climate , 1992 .

[47]  G. Wick,et al.  Satellite and CALJET Aircraft Observations of Atmospheric Rivers over the Eastern North Pacific Ocean during the Winter of 1997/98 , 2004 .