Assessing the U.S. Navy Coupled Ice-Ocean Model vs. Recent Arctic Observations David A. Hebert 1, Richard Allard 1, Pamela Posey 1, E. Joseph Metzger 1, Alan Wallcraft 1, Shelley Riedlinger 1, Steve Piacsek 1, Michael Phelps 2 1 Naval Research Lab, Stennis Space Center, MS 2 Jacobs Technology Inc., Stennis Space Center, MS

Motivation Observations and Models How well does our model do? Metrics? – Ice thickness, snow depth, T/S profiles Assimilation – Helps keep model on track. We only want to compare with non-assimilated data 24 OCT nd FAMOUS Meeting, Woods Hole, MA

ACNFS (Arctic Cap Nowcast/Forecast System) Domain: o N High resolution: 3.5 km at pole Assimilation of ocean and ice concentration 7 day forecast daily ACNFS consists of : – Ice Model – CICE V4.0 – Ocean Model – HYCOM – Data assimilation – NCODA – Forced with 0.5 o NOGAPS As of 28 AUG 2013, 0.5 o NAVGEM 24 OCT nd FAMOUS Meeting, Woods Hole, MA

Observations we looked at 1.Ice/Snow Thickness 1.Ice Bridge (NASA) 2.Ice Mass Balance Buoys (CRREL) 3.Beaufort Gyre Upward Looking Sonar (WHOI) 2.Ocean Data 1.Ice Tethered Profilers (T, S Profiles) (WHOI) 2.McLane Moored Profiles (T,S,U,V) (WHOI) 3.GDEM4 – Climatology T/S 24 OCT nd FAMOUS Meeting, Woods Hole, MA

Ice Bridge OCT nd FAMOUS Meeting, Woods Hole, MA 2013

Ice Bridge OCT nd FAMOUS Meeting, Woods Hole, MA 2013

Ice Bridge - Beaufort Sea meters meters 24 OCT nd FAMOUS Meeting, Woods Hole, MA

Ice Bridge - Canadian Archipelago meters meters 24 OCT nd FAMOUS Meeting, Woods Hole, MA

Ice Bridge - Central Arctic meters meters 24 OCT nd FAMOUS Meeting, Woods Hole, MA

IMBB Ice Thickness - CRREL 24 OCT 20132nd FAMOUS Meeting, Woods Hole, MA10 ACNFS IMBB

MMP/ULS - WHOI 24 OCT nd FAMOUS Meeting, Woods Hole, MA

ULS Ice Draft - WHOI Draft = 0.88 Ice thickness Aug 2011-Aug hour moving average Model too thick Model growth OK. Model Melt: not so much… RED = ULS BLACK = ACNFS Mooring D Mooring A 24 OCT nd FAMOUS Meeting, Woods Hole, MA

MMP - Temperature 24 OCT nd FAMOUS Meeting, Woods Hole, MA

MMP - Salinity 24 OCT nd FAMOUS Meeting, Woods Hole, MA

MMP – U velocity 24 OCT nd FAMOUS Meeting, Woods Hole, MA

MMP – V velocity 24 OCT nd FAMOUS Meeting, Woods Hole, MA

MMP vs. ACNFS Temp OCT nd FAMOUS Meeting, Woods Hole, MA

MMP vs. ACNFS Temp OCT nd FAMOUS Meeting, Woods Hole, MA MMPHYCOM

MMP vs. ACNFS Salinity OCT nd FAMOUS Meeting, Woods Hole, MA

MMP vs. ACNFS Salinity OCT nd FAMOUS Meeting, Woods Hole, MA MMPHYCOM

GDEM - ACNFS - MMP T 24 OCT 20132nd FAMOUS Meeting, Woods Hole, MA21 Summer GDEM4 MMP ACNFS Winter

GDEM - ACNFS - MMP S 24 OCT 20132nd FAMOUS Meeting, Woods Hole, MA22 Winter Summer GDEM4 MMP ACNFS

ITP41 – WHOI 24 OCT nd FAMOUS Meeting, Woods Hole, MA

ITP41- WHOI Weaker upper warm layer Cooler at depth Model too saline at surface 24 OCT nd FAMOUS Meeting, Woods Hole, MA

Summary Many observations used to compare with ACNFS – ITP, IMBB, MMP, ULS, Ice Bridge ACNFS too thick compared with Ice Bridge – Especially in Canadian Archipelago Ice growth rate good during freezing season Do not melt ice fast enough – Parameter tuning for albedo, melt ponds? – Ocean Mixed Layer? 24 OCT nd FAMOUS Meeting, Woods Hole, MA

Summary In Beaufort ACNFS has too strong upper ocean velocity ACNFS smooth upper ocean temp profile – Vertical resolution? ACNFS salinity good at depth, too saline at surface – Not enough fresh water flux from ice melt? – Brine rejection parameterization? (New start project this year) 24 OCT nd FAMOUS Meeting, Woods Hole, MA

MMP Mooring D – 4 seasons 24 OCT 20132nd FAMOUS Meeting, Woods Hole, MA27

Temp MMP, ACNFS, GDEM4 24 OCT 20132nd FAMOUS Meeting, Woods Hole, MA28 Cast ACNFS GDEM4

Assimilated T/S

Ice Thickness 2013 March 1, 2013April 1, 2013May 1, 2013