NEMO Modelling NSERC – CCAR Projects VITALS Geotraces Photo courtesy Department of Fisheries and...
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Transcript of NEMO Modelling NSERC – CCAR Projects VITALS Geotraces Photo courtesy Department of Fisheries and...
NEMO Modelling
NSERC – CCAR Projects
• VITALS• Geotraces
Photo courtesy Department of Fisheries and Oceans
Paul G. Myers, Xianmin Hu, Amber M. Holdsworth, Clark Pennelly, Laura Castro de la Guardia, Laura Gillard, Jingfan Sun, Margaret Campbell, Peggy Courtois, Nathan Grivault, Yarisbel GarciaDepartment of Earth and Atmospheric SciencesUniversity of Alberta
Model ConfigurationModel Configuration
km
ANHA: Arctic and Northern Hemisphere Atlantic
ANHA12
Model : NEMO 3.4 LIM2 + EVP
Mesh : 1632 x 2400 50 levels
Resolution : 1/12 degree
LS : ~ 5 km
CAA : ~ 4 km
Experiment SetupExperiment Setup
Initialization:
Atmospheric forcing (CGRF, hourly):
NO temperature & salinity restoring
Jan 2002 – 2008 -- > 2010
3D T, S, U and V (GLORYS1v1, Jan02)
Sea Ice
Snow: CORE2 (IA)
Runoff: Dai and Trenberth climatology
T2, Q2, U10, V10 Precipitation Radiation (SW & LW)
CGRF: CMC GDPS reforecasts CMC: Canadian Meteorological Centre
GDPS: Global Deterministic Prediction System GLORYS: GLobal Ocean ReanalYses and Simulations
OBC: U, V, T and S (GLORYS1v1)
Labrador Sea in ANHA12
Sea Ice Concentration
Velocity magnitude averaged over top 55 m
Mixed Layer Depth
Sea Ice Thickness
Also: animations (2003-2008) at http://knossos.eas.ualberta.ca/myers/NEMO.html
CAA in ANHA12
Sea Ice Concentration
Sea Ice Thickness
Also: animations (2003-2008) at http://knossos.eas.ualberta.ca/myers/NEMO.html
West Lancaster Sound Fluxes
GLORYS 2v3 vs GLORYS1v1(volume flux through Bering Strait and Lancaster Sound)
NEMO Updates
Compute snow fall from total precipitation based on 2-m air temperature
Fixed a discontinuity “line” in wind stress field
Update runoff with a new interpolation approach
CICE with NEMO3.4 (workable but not tested for long simulation)
NEMO Updates
compute snow fall from total precipitation based on 2-m air temperature
fixed a discontinuity “line” in wind stress field
update runoff with a new interpolation approach
CICE with NEMO3.4 (workable but not tested for long simulation)
RUNOFF UpdateDai and Trenberth 1o x 1o gridded data
Distribute gridded runoff
into “coast-buffer-zones”
volume volume conservedconserved
salinity changes in top 50m
MLD
changes
Planned RUNs
solid line: finished runsdash/dotted: planned simulation/re-run with updated dataorange text: finished or expected finish timetime schedule for simulation with CGRF after 2010 is still not known
Sea Ice Model Comparison
Select Ice Thickness Validation
Accumulated Winter Thermodynamic & Dynamic Ice Thickness Change
unit: m
AGRIF: Adaptive Grid Refinement In Fortran1
X:240
Y:29
0
X:724
Y:87
4
AGRIF0.25
0.20
0.15
0.10
0.05
0.00
5
4
3
2
1
0
A
B
1Debreu, Laurent, Christophe Vouland, and Eric Blayo. "AGRIF: Adaptive grid refinement in Fortran." Computers & Geosciences 34.1 (2008): 8-13.
1/12°
AGRIF
Transformation(1:3 Horiz. ratio)
ControlGrid Box
1/4°1/12°
1/12
°
1/4°
AGRIF1/12°
X:814
Y:54
4
ANHA4: ¼° resolution (parent)
•High resolution nest: better resolving skill•Simulation runs alongside parent•AGRIF forced by separate set of data•AGRIF boundaries supplied by parent•Computational expense: 2-4 X
Ice
velo
city
[m/s
]Ic
e Th
ickn
ess
[m]
AGRIF Grid Boxes
X:270
Y:18
0
04/18/23
Effect of enhanced melt from Greenland Ice sheet?
Warming of our climate is melting Greenland glaciers
Deep convection in the Labrador
Sea
Sea level rise
Increase freshwater input in Baffin Bay
Feedbacks?Hydrography? Circulation?Exchanges?
Greenland ice sheet mass loss trend 2003-2008
(237km3/yr)
Experiments 1 to 9:Exp. 1 Control run
Exp. 2- 9 enhance melt from west Greenland, between 158- 1580 km3/yr
17
Freshwater Pathways into the North Atlantic from the Canadian
Arctic Archipelago and the Greenland Ice Sheet
• Understand pathways of freshwater into the North Atlantic Ocean
• Fluxes through Fury and Hecla Strait • Relative role compared to other gateways through the
Canadian Arctic Archipelago. • Pathways for the freshwater discharged from major
tidewater glaciers around Greenland• Function of time and glacier location
• Pathways of Irminger Water to coastal Greenland
Laura C. Gillard and Paul G. MyersDepartment of Earth and Atmospheric Sciences
University of Alberta
Holloway and Proshutinsky 2007
ANHA 1/12⁰ Configuration
All questions will be examined by using output from a suite of ocean general circulation models (NEMO) at 1/4 ⁰ and 1/12⁰, as well as Lagrangian particle tracking tool for trajectory analysis
Fury and Hecla Strait
Probabilities from forward trajectories, run at 1/4 ⁰ resolution, initiated at Helheim Glacier