Changes in the climatology, structure, and seasonality of northeast Pacific atmospheric rivers in CMIP5 climate simulations

AbstractThis paper describes changes in the climatology, structure, and seasonality of cool-season atmospheric rivers influencing the U.S. West Coast by examining the climate simulations from phase 5 of the Coupled Model Intercomparison Project (CMIP5) that are forced by the representative concentration pathway (RCP) 8.5 scenario. There are only slight changes in atmospheric river (AR) frequency and seasonality between historical (1970–99) and future (2070–99) periods considering the most extreme days (99th percentile) in integrated water vapor transport (IVT) along the U.S. West Coast. Changes in the 99th percentile of precipitation are only significant over the southern portion of the coast. In contrast, using the number of future days exceeding the historical 99th percentile IVT threshold produces statistically significant increases in the frequency of extreme IVT events for all winter months. The peak in future AR days appears to occur approximately one month earlier. The 10-model mean historical and ...

[1]  D. Stone,et al.  Testing the Clausius–Clapeyron constraint on changes in extreme precipitation under CO2 warming , 2007 .

[2]  L. Leung,et al.  A projection of changes in landfalling atmospheric river frequency and extreme precipitation over western North America from the Large Ensemble CESM simulations , 2016 .

[3]  Ying-Hwa Kuo,et al.  Diagnosis of an Intense Atmospheric River Impacting the Pacific Northwest: Storm Summary and Offshore Vertical Structure Observed with COSMIC Satellite Retrievals , 2008 .

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

[5]  G. Magnusdottir,et al.  An evaluation of atmospheric rivers over the North Pacific in CMIP5 and their response to warming under RCP 8.5 , 2015 .

[6]  H. L. Miller,et al.  Global climate projections , 2007 .

[7]  J. Kiehl,et al.  Simulating the Pineapple Express in the half degree Community Climate System Model, CCSM4 , 2016 .

[8]  J. Gyakum,et al.  Heavy Cold-Season Precipitation in the Northwestern United States: Synoptic Climatology and an Analysis of the Flood of 17-18 January 1986 , 1999 .

[9]  Clifford F. Mass,et al.  Estimates of Twenty-First-Century Flood Risk in the Pacific Northwest Based on Regional Climate Model Simulations , 2014 .

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

[11]  E. Barnes,et al.  All-Season Climatology and Variability of Atmospheric River Frequencies over the North Pacific , 2016 .

[12]  F. Martin Ralph,et al.  Climatological characteristics of atmospheric rivers and their inland penetration over the western united states , 2013 .

[13]  Eric J. Fetzer,et al.  Classification of atmospheric river events on the U.S. West Coast using a trajectory model , 2014 .

[14]  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 .

[15]  C. Mass,et al.  Wintertime Extreme Precipitation Events along the Pacific Northwest Coast: Climatology and Synoptic Evolution , 2012 .

[16]  E. Chang,et al.  CMIP5 multimodel ensemble projection of storm track change under global warming , 2012 .

[17]  Michael D. Dettinger,et al.  Observed Impacts of Duration and Seasonality of Atmospheric-River Landfalls on Soil Moisture and Runoff in Coastal Northern California , 2013 .

[18]  Clifford F. Mass,et al.  Extreme Precipitation over the West Coast of North America: Is There a Trend? , 2011 .

[19]  C. Mass,et al.  Changes in Winter Atmospheric Rivers along the North American West Coast in CMIP5 Climate Models , 2015 .

[20]  Harald Sodemann,et al.  Moisture Origin and Meridional Transport in Atmospheric Rivers and Their Association with Multiple Cyclones , 2013 .

[21]  Y. Qian,et al.  Dynamical and thermodynamical modulations on future changes of landfalling atmospheric rivers over western North America , 2015 .

[22]  F. Martin Ralph,et al.  Flooding in Western Washington: The Connection to Atmospheric Rivers* , 2011 .

[23]  F. Martin Ralph,et al.  Climate change intensification of horizontal water vapor transport in CMIP5 , 2015 .

[24]  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 .

[25]  Martin S. Singh,et al.  Upward Shift of the Atmospheric General Circulation under Global Warming: Theory and Simulations , 2012 .

[26]  Corinne Le Quéré,et al.  Climate Change 2013: The Physical Science Basis , 2013 .

[27]  M. Nuñez,et al.  Climatology of Winter Orographic Precipitation over the Subtropical Central Andes and Associated Synoptic and Regional Characteristics , 2011 .

[28]  Elizabeth A. Barnes,et al.  Response of the Midlatitude Jets, and of Their Variability, to Increased Greenhouse Gases in the CMIP5 Models , 2013 .

[29]  J. Kiehl,et al.  Atmospheric river landfall‐latitude changes in future climate simulations , 2016 .

[30]  Eric P. Salathe,et al.  Influences of a shift in North Pacific storm tracks on western North American precipitation under global warming , 2006 .

[31]  F. Martin Ralph,et al.  The Development and Evolution of Two Atmospheric Rivers in Proximity to Western North Pacific Tropical Cyclones in October 2010 , 2013 .

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

[33]  K. Browning,et al.  Structure of low‐level jet streams ahead of mid‐latitude cold fronts , 1973 .

[34]  Sarah M. Kang,et al.  Expansion of the Hadley Cell under Global Warming: Winter versus Summer , 2012 .

[35]  Gabriele Villarini,et al.  Future changes in atmospheric rivers and their implications for winter flooding in Britain , 2013 .

[36]  M. Dettinger Climate Change, Atmospheric Rivers, and Floods in California – A Multimodel Analysis of Storm Frequency and Magnitude Changes 1 , 2011 .