The Arctic Ocean in CMIP5 Simulations Yanni Ding1, James Carton1, and Gennady Chepurin1 (& Mike Steele & Sirpa H.) 1Dept. Atmospheric and Ocean Science, UMD FAMOS 2013 11/21/2018 ERS-2/Envisat tandem flight (from pictures kindly provided by ESA)

Historical ensembles full forcing Models Historical ensembles full forcing 1860-2005 Model Name Model Center Ocean resolution Grid 1 CanESM2 Canadian Centre for Climate Modelling and Analysis 1.4⁰x0.9⁰x40lev regular 2 CCSM4* National Center for Atmospheric Research 1.1⁰x(0.27⁰-0.54⁰)x60lev displaced 3 CNRM-CM5 CNRM, France 1⁰x(1/3⁰-1⁰)x42lev tripolar 4 CSIRO-Mk3.6.0 CSIRO, Austrilia 1.875⁰x0.9375⁰x31lev 5 GFDL-CM3 Geophysical Fluid Dynamics Laboratory 1⁰x(1/3⁰-1⁰)x50lev 6 GFDL-ESM2M 7 GFDL-ESM2G 8 GISS-E2-H NASA Goddard Institute for Space Studies 1⁰x1.25⁰x32lev 9 GISS-E2-R 1⁰x~1⁰x32lev 10 HadCM3 Met Office Hadley Centre, U.K. 1.25⁰x1.25⁰x20lev 11 HadGEM2-ES* 1⁰x(1/3⁰-1⁰)x40lev 12 IPSL-CM5A-MR Institut Pierre-Simon Laplace, France 2⁰x2⁰x39lev 13 MPI-ESM-LR* Max Planck Institute for Meteorology, Germany 1.5⁰x1.5⁰x40lev 14 MRI-CGCM3* Meteorological Research Institute, Japan 1⁰x0.5⁰x50lev 15 NorESM1-M Norwegian Climate Centre 1⁰x1⁰x70lev *Wang and Overland (2012) approved

Annual Sea Level Pressure 1860-2004 L L H H L L HadSLP2 L Siberian & Beaufort High, Aleutian and Icelandic lows H L (Allan and Ansell 2006) Unit: mb

Fresh Water storage (for Andrey) 1950-2005 Observation Fresh water is defined as the the salinity less than the mean SSS to the north of 75N (Serreze et al. 2006) Unit: m

Mean ocean volume transport {still checking this} Obs CanESM2 GISS-E2-H HadGEM2-ES Bering Strait 0.96Sv 0.16Sv 0.66Sv Greenland-Iceland -5.97 -4.16 -7.84 East of Iceland 5.02 4.08 7.72 West of Greenland -0.01 -0.2 -0.67 0.8Sv 7-7.2Sv Gfdl cm3 has +2Sv through CAA -1.8-2.2Sv

Salinity (colors), Temperature (contours) at 150m depth Annual climatology TEMPERATURE SALINITY (Carton et al. 2011)

Differences in Atlantic water along 68N Salinity (colors), Temperature (contours) along 68N -0.1 0.1

AW variability

AW Temperature anomalies CCSM4 AW Temperature anomalies GFDL-CM3

Temperature/Salinity relationship for GFDL-CM3

Advection: lag correlation between SST’ and AW SST’ HadCM3 Run # 5 3 1 Local net surface heating rate vs heat storage anomalies 4 2 4

NAO Forcing OBSERVED (Dickson et al., 2000)

NAO index vs heat content for HadCM3 [NAO index : 1st PC of winter SLP’] HC’ NAO

Arctic Ocean HC changes: 1986-2005mean – 1861-1880mean (e.g. Boe et al. 2009)

Some Points for Discussion Time mean Time mean states ~ in line with observations but transports are different. ‘Atlantic Water’ is present, although its T/S characteristics vary Seasonal {see poster} Variability Active AW variability. Both interactions with the atmosphere (e.g. surface heating) and exchanges with the Atlantic subpolar gyre are involved. NAO in all models but its centers are displaced. NAO not driving most AW variability. The way heating is being distributed in the Arctic on centennial timescales varies(we’re just beginning to look at this). We’d be interested in a group organizing some comparative analysis of the CMIP5 results