CESM/RACM/RASM Update

May 15, 2012

Since Nov, 2011

• ccsm4_0_racm28:racm29:racm30– vic parallelization– vic netcdf files– vic coupling mods and “273.15” fixes– wrf update to remove u* averaging– new datm forcing for pop/cice “H” cases– update racm utilities (post-processing tools)

RACM Component Model Performance

• racm29+, parallel vic, wr50a_ar9v4, raptor, out-of-box I/O, 10 day tests, no restarts

0 0.5 1 1.5 2 2.5 3 3.50

50

100

150

200

250

300

350

400

450

500

wrfviccicepop

sec/model_day

processors

1 10 100 1000

CCSM pe layouts• For science, surface fluxes must be computed with latest atm state. So

land (in land), sea ice (in ice), and ocean flux calculation (in coupler) must be run sequentially with the atm model.

land

ice

ocean

atm

coupler

land ice

oceanatm

couplerland ice ocean

atm

coupler

sequential hybridconcurrent

hybridconcurrent “2”

RACM Throughputtotal pes throughput

(model years / wall day)

cost (pe-hrs/model year)

atm pes

lnd pes

ice pes

ocn pes

layout

256 0.30* 20200 256 1 256 256 seq

336 0.54 14900 272 16 256 64 hyb conc

432 0.66 15800 336 16 320 96 hyb conc

512 0.71 17400 512 16 512 512 seq

656 0.83 19800 528 16 512 128 hyb conc

1040 0.97 25700 656 16 1024 384 hyb conc2

* old setup with faster cice

Ongoing RASM Work• RACM version

– Continued scientific validation– vic exact restart testing

• RASM version of the model based on CESM1.1– New features

• Supports gregorian calendar• Updated vector mapping over pole• Other features like pio

– WRF/CLM “PK, PF” cases running– WRF/VIC/POP/CICE wr50a_ar9v4 “RB” next then

• datm/pop/cice “H”• WRF/CLM/?• CISM configurations?• runoff?

– Testing and validation

NCAR/CESM1.1 update

• target CESM1.1 version due out late-2011 or mid-2012 late 2012

• WRF now part of CESM1.1 development version for internal NCAR testing (wrf will NOT be part of CESM1.1 community release)

• WRF coupling in CESM validation continues within NCAR• Runoff may become separate component in summer 2012• Still need to address

– CESM vs WRF repositories/compatability/relationship– WRF integration in CESM (build, namelist generation, I/O unit

numbers, file name convention, restart validation, limitiations on input file streaming, etc)

Performance

• time in seconds/model day (vic on 1 pe)• Limited by vic running on 1 pe, should be solved soon.• Next slowest component is wrf.

– time steps are expensive– scaling fine to about O(100) gridcells/pe, that’s O(500) pes for wr50a

resolution– standard weather case are run O(days), we want to run O(years)

• pop and cice scaling not currently an issue.

pes wrf vic pop cice cpl64 550 335 288 215 22128 307 332 114 104 11256 190 334 56 54 6512 137 332 29 27 3

Overview of RACM version

• based on CCSM4.0 (released April 2010)– add wrf as atm component– add vic as lnd component– extend pop/cice to allow distinct coupling grid– coupling non-identical regional grids– no changes to coupling fields relative to ccsm4

• lives in NPS repository• raptor, garnet, chugach primary compute platforms• other users• wrf coupling being reviewed at NCAR

RACM Configurations

• Compsets– H = datm, slnd, pop, cice– RB = wrf, vic, pop, cice– RI = datm, vic, socn, sice– RJ = wrf, dlnd, pop, cice– RK = wrf, vic, docn, dice– RL = wrf, dlnd, docn, dice

• Grids– wr50a, w5a = wrf 50 km grid (205x275)– ar9v3, a93 = ocean/ice RACM 9 km grid (1280x720)– ar9v4, a94 = extended ocn/ice RACM grid (1560x1080)

RACM Regional Non-Uniform Gridspop/cice extended region values

specified from observations, set inside pop and cice at top level coupling interface

3 regions• blue: standard atm/ocn

2-way coupling• pink: atm + extended

ocean (atm needs forcing, ocean does not forcing but it exists)

• purple: no atm + extended ocn (coupling unimportant)

pop/cice (extended)

wrf/vic

pop/cice