1. Provided by Eric P. Chassignet, COAPS, Florida State University HYCOM High Resolution Modeling

2. HYCOM with Tides HYCOM with Tides  Includes tidal forcing and slightly increased interfacial diffusion  7/2003 – 06/2008  8 largest constituents (M2, S2, K1, O1, N2, P1, K2, Q1) forward tides  Whole domain daily averaged files  Hourly 3-D archive files, Global: May 2004 Small subdomains: 08/2005 – 06/2008 Twin 1/12  Global HYCOM Simulations HYCOM without Tides HYCOM without Tides  Climatological spin-up: 1979-2002 2 nd ECMWF Reanalysis scaled to QuikSCAT wind speed  Then 01/2003 – 06/2008 3-hourly 0.5° NOGAPS forcing scaled to QuikSCAT  KPP mixed layer  Advect T & S  Daily global 3-D archive files Arbic, Wallcraft, and Metzger

3. Sea Surface Elevation Error in HYCOM with Winds and Tides ConstituentSignal (cm)Error (cm)% Variance Q1Q1 1.62 0.6882.1 O1O1 7.76 2.4889.7 P1P1 3.62 0.7995.2 K1K1 11.26 2.4895.1 N1N1 6.86 1.4095.9 M2M2 33.22 8.2693.8 S2S2 12.62 5.1783.2 K2K2 3.43 1.6576.9 RSS39.0410.6392.6 Computed with standard set of 102 pelagic tide gauges (Shum et al. 1997)

4. Eddy Resolving Global Prediction With Tides Hourly steric SSHHourly non-steric SSH Internal tidal signature seen in the steric SSH signal Propagation of tides is consistent with Robertson and Ffield (2008) Eight largest tidal constituents in a 32-layer.08° global HYCOM simulation with NOGAPS atmospheric forcing

5. Difference in Steric SSH Over 6 Hours June 30 2006: 06Z – 00Z -10 -5 0 5 10 (cm)

6. Climatological spin-up: Start from January GDEM3 climatologyStart from January GDEM3 climatology 1979-2002 ERA-40 scaled to QuikSCAT wind speed1979-2002 ERA-40 scaled to QuikSCAT wind speed KPP mixed layerKPP mixed layer Improvements over earlier 1/12  simulations:Improvements over earlier 1/12  simulations: Equation of state quadratic (vs linear) in salinity Equation of state quadratic (vs linear) in salinity More accurate thermobaric correction More accurate thermobaric correction More accurate vertical remapping of layers More accurate vertical remapping of layers Also run a 1/12  exact twin Also run a 1/12  exact twin Both have run for 5 model years Both have run for 5 model years Zamudio, Metzger, Wallcraft Initial 1/25° Global HYCOM Simulation

7. Gulf Stream Sea Surface Height Variability a)Along-track from four satellite altimeters (Hurlburt and Hogan, 2008) b) 1/12  global model year 3 c) 1/25  global model year 3 (a) (c)(b)