Meeting Notes
1. ASM workshop – 19-21 May 2008
- 50 people max
- suggestions for participants (international) – for new ideas
- Bromwich (Arctic reanalysis) involved
- social scientists – yes
- coupling experrts
2. IARC Summer School – tell my students!!
- social scientists??
Website:
http://www.iarc.uaf.edu/education_outreach/summer/
2008/
3. ASM planning
- involve coupling experts (IARC) postdocs in DOE project
- keeping modular structure is very important for scientific and also diplomatic reaasons
- Google group (sign up!):
arctic-system-model@googlegroups.com
http://groups.google.com/group/arctic-system-model
4. DOE project
- plan for group kick-off meeting?
- coupler – WRF and ROMS have been linked through NCAR coupler?
- physical feedbacks and future scenarios studies with sea-ice focus
5. Core coupler exchanges
- freshwater/salinity flux to ocean
6. Coupler advances
- temperature (heat flux) into ocean by rivers
- sediment transport (rivers to ocean)
- ecosystem/biology models
7. Other
(a) land ice, esp. Greenland. Can get fluxes to ocean already.
- model it? LANL w/NCAR is working on an ice-sheet model (Bill Lipscomb).
Can deal with other land ice. Working within CCSM framework – so amenable to our
approach.
(b) Run WRF for summer 2007 with (specified) and without (obs) sea-ice
(c) Does AO warming require input (lateral fluxes) via North Atlantic?
8. What does Anjuli need to promote her program?
- Outcomes along the way (e.g., summer 2007 run)
9. What does IARC & ARSC need to promote their programs?
- Give thanks for ARSC involvement already supporting our work
10. SciDAC/INCITE/ARSC resources – plans to optimize usage of resources
(a) resolution increases? What is of value for ocean, land, atmosphere?
(b) ensembles
(c) regional increases in resolution (nesting)
11. Wieslaw’s paper
- virtually no sensitivity to reasonable changes in size of relaxation time
- bigger issue in more general modeling: radiative fluxes from atmosphere
- get surface fluxes from Wieslaw’s different simulations to compare with what WRF
produces in stand-alone mode (including momentum exchanges)
- see also Rinke et al. paper from Wieslaw: influence on atmospheric simulation by
d(SST) and d(ice thickness)
12. Andrew – High Frequency Sea Ice Dynamics Component
- semi-diurnal (inertial) effects on sea ice
- implementation may require treating ice dynamics as an intrinsic part of ocean (i.e., can
not communicate via flux coupler)
13. WRF
(a) Mark – simulations to evaluate where we are with polar WRF. Long simulations to
evaluate drift & work to minimize errors.
Also – Ohio St. group will assist. OSU focused on weather prediction (strung together
into a continuous stream of output)
(b) esp. errors in radiation and clouds
(c) Dave Morrison (NCAR) – work on improving cloud microphysics
(d) prior MM5 experience – cloud problems in Antarctic + lessons learned from MM5
have been implemented into WRF (e.g., specified nuclei present for clouds).
(e) MSLP errors – similar to MM5 errors?
14. He & WRF coupling
(a) subroutine coupling vs. concurrent coupling
15. IT site
(a) web site
(b) data repository
(c) software archive with version control
16. Dennis + VIC + NOAH
(a) Dennis has VIC, NOAH and CLM in a system where they can all be run off line. We
can do tests where we supply WRF output to drive all three, esp. to understand how VIC
and NOAH will differ in behavior.
(b) Each model can supply fluxes in a data set that the coupler uses to drive the other
models “off line”. This would be a precursor to the full, interactive coupling.
17. Ice model
- Ready to couple
- Lots of validation: ocean and ice realistic
- Upgrading to POP 2.0, running a spin-up, coupled to LANL CICE
- CICE 4.0 will be the same code at NCAR and LANL
- multiple ice categories (fractional coverages)  better thermodynamics. Ice strength a
function of thinnest ice fraction.
- EVP or VP parameterization? Can be tested down the road.
18. Ocean model
- working great
- res. finer than 10 km? potential to resolve ocean eddies. Bering Sea power spectra:
similar down to about 100 km, then obs and model diverge – obs have higher energy.
Deformation radius is approx. 10 km – need to resolve it.
- tides: important contribution to barotropic flow. See esp. Barents Sea. (tides approx. 2
meters). May influence heat exchange with atmosphere. Residual tidal currents.
- Model already can compute surge of basin water against coast by persistent strong
winds (but not the significant waves, of course).
- Old coupler linking ocean and ice should be removable fairly readily, allowing for
implementation of cpl6.
Need:
1. Parallel development tasks (stand-alone diagnosis, coupler development, simulation
using coupler, etc.)
2. Priorities for coupler information flow
- what do we need to be passing to the coupler and to be receiving from coupler?
3. Planning for full science team (PIs, postdocs, grad students, invited guests) meeting
- just before/after ASM meeting? Boulder, Thursday/Friday before.
- invite Greg Newby, John W., Larry H., Don Bahls, Ed Kornkven
ARSC software engineer(s)?
Dave Bromwich or Keith Hines
Item 2 – coupler priorities
1. Homework assignment – who is working on it?
He, Jaromir, Mark S., Zhu
2. Components:
(a) WRF
OUT: State variables:
Lowest model level: Air T, wind speed/direction, specific humidity
Surface air pressure
Fluxes: Downwelling shortwave and longwave radiation,
frozen precipitation, non-frozen precipitation
IN:
Sensible, latent and momentum fluxes
Upwelling SW and LW radiative fluxes
(b) Ocean model
OUT: State variables: <nothing needed>
Fluxes: Air-ocean stress, air-ice stress, sensible & latent heat flux,
upwelling SW and LW radiative flux
IN:
Lowest atmospheric model level: Wind speed and direction, air T,
specific humidity, surface air pressure (or air density)
Atm Fluxes: SW down and LW down, precipitation
Land model: Runoff volume and temperature
(c) CICE
OUT: State variables: <nothing needed>
Fluxes: Air-ocean stress, air-ice stress, sensible & latent heat flux,
upwelling SW and LW radiative flux
IN:
Lowest atmospheric model level: Wind speed and direction, air T,
specific humidity, surface air pressure (or air density)
Atm Fluxes: SW down and LW down, frozen precipitation, non-frozen
precipitation
Further modifications to come, for ocean-ice interactions
(d) VIC
OUT: State variables: <none needed>
Fluxes: SW upward, LW upward, sensible and latent heat fluxes,
momentum flux, runoff volume and temperature
IN:
Lowest atmospheric model level: Wind speed, air T, specific humidity,
surface air pressure
Atm Fluxes: SW down and LW down, frozen precipitation, non-frozen
precipitation
Item 1 – Development lines – next 6 months
1. NPS
(a) New POP and CICE coupled to cpl6 coupler and steps toward getting appropriate
information flow for other components.
2. UWa
(a) VIC linked to cpl6. Test by repeating offline runs, with input going through coupler.
(b) Link VIC to WRF directly, as done with NOAH?
3. UCo
(a) Run stand-alone WRF for ARCMIP and pan-Arctic domains, to evaluate polar WRF.
(b) Evaluating model physics: clouds, radiation
(c) Follow WRF 3.0 development, especially when Mark goes to WRF workshop.
4. ISU
(a) Evaluation of circulation properties produced by WRF runs
(b) WRF tutorial – late June
5. IARC
He: Coupling of WRF with cpl6:
(a) Couple of WRF with data sets it used or generated in its own stand-alone simulations.
(b) “Couple” with other component models via data sets they produced in stand-alone
simulations.
(c) Couple WRF to other model components
Andrew: Coupling of ice and ocean
(e) Coming up to speed with Arctic-POP CICE code
(f) Intercomparisons with buoy data – focused on semi-diurnal oscillations
(g) Numerical procedures for coupling with barotropic mode