Running the GFS Parallel System

Hybrid GSI/EnKF on Zeus NOAA/NWS/NCEP/EMC

This presentation contains…

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Overview of Hybrid GDAS structure Running an experiment on Zeus w/ Hybrid (DEMO)   New variables in configuration file New model input   Submitting jobs with the Hybrid EnKF New model output Suggestions for running experiments with the Hybrid EnKF

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Documentation & Help

Website: http://www.emc.ncep.noaa.gov/GFS/exp.php

Listserv (Glopara Support): [email protected]

In Person: Stop by my cube next to the 2 nd breakroom, I don’t bite  floor

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Hybrid Var-EnKF

 What’s

hybrid

in the hybrid GDAS?

J 

x

 f  J , 

α

   Augment fixed background error with    β   1 2 f 

H

  

x

 f   1 2 1 T 

y

 

B

   1

x

T   

R

t tropical winds

B

f  1 f   1    T β

H x

 t

R

  1  1 2

y

  n N    1

x



   

 fit to bkg  fit to obs   fits to observations

where

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t  

x

 f  N  

α

cool season CONUS precipitation n 

x

e n   ens fcst

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prep echk eobs GDAS Hybrid Var-EnKF Flow Chart anal angu fcst post arch echk vrfy eomn eupd ecen efmn epos eomg01 eomg02 eomg03 eomg04 eomg05 eomg06 eomg07 eomg08 eomg09 eomg10 efcs01 efcs02 efcs03 efcs04 efcs05 efcs06 efcs07 efcs08 efcs09 efcs10 earc

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EnKF job steps

(start to update)  echk  check file availability  eobs  select observations used in ensemble innovations   eomn  submit and monitor ensemble innovation jobs eomg01,…, eomg10  compute ensemble innovations (8 members/job)  eupd  compute ensemble analyses (EnKF update code)

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EnKF job steps

(re-center to archive)  ecen  recenter ensemble analyses about hires analysis   efmn  submit and monitor ensemble forecast jobs efcs01,…, efcs10  run ens fcst (8 members/job)  epos  compute ensemble mean  spectrally smooth ens fcst  earc  save data & cleanup

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WARNING!!!

 Hybrid GDAS generates a LOT of output  80 member T254L64 ensemble  1316 files / cycle  90.8 Gbytes / cycle

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Alternatives

 Ask yourself - Do I really need to run hybrid GDAS?

 Can I use a lower resolution?

 T382 hires, T190 ensemble  T254 hires, T126 ensemble  Can I just run the GFS long forecast?

 Use ICs from Hybrid EnKF control runs

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GFS Hybrid EnKF Experiment (DEMO)

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New variables in configuration file 2.

New model input 3.

Submitting jobs with the Hybrid EnKF 4.

New model output Demo matches Zeus control prhy2s: /NCEPDEV/hpssuser/g01/wx24kh/Zeus/para_gfs/prhy2s

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Demo time…

Needed files:  Config file & rlist: /scratch2/portfolios/NCEPDEV/global/save/Kate.Howard/TUTORIAL/prhy2s  Input/output in COMROT: /scratch2/portfolios/NCEPDEV/global/noscrub/Kate.Howard/TUTORIAL/prhy2s

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Demo time…

Experiment prhy2s:  CDATE = 2012072512  CDUMP = gdas  CSTEP = fcst1  gfs_cyc = 1 (run only 00z GFS)  DOENKF & DOHYBVAR = YES (Hybrid EnKF DA)  EDATE = 2012072600  EDUMP = gdas  ESTEP = prep

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Configuration File – New Variables

 To turn the Hybrid EnKF on:  DOHYBVAR=YES  Tells analysis to use ensemble product  DOENKF=YES  Turns on ensemble process scripts

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Initial Conditions in $COMROT

Acquire initial condition files and place in $COMROT: 1.

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biascr.$CDUMP.$CDATE satang.$CDUMP.$CDATE sfcanl.$CDUMP.$CDATE siganl.$CDUMP.$CDATE sfcanl_$CDATE_mem$MEM ($MEM = member # 1-80) siganl_$CDATE_mem$MEM Where do I find Hybrid EnKF ICs?

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Where to find ICs

Places to acquire Hybrid EnKF control ICs for Zeus: 

prhy2s

- Summer 2012 control (July – September)  HPSS: /NCEPDEV/hpssuser/g01/wx24kh/Zeus/para_gfs/prhy2s 

Tutorial input

 HPSS: /NCEPDEV/hpssuser/g01/wx24kh/Zeus/TUTORIAL/prhy2s

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Submitting the GFS w/ Hybrid EnKF

While in $EXPDIR, using the psub script from config file, type the following on the command line:

$PSUB $CONFIG $CDATE gdas fcst1 $PSUB $CONFIG $CDATE gdas efmn

post prep anal echk eobs eomn eomg## eupd angu echk ecen fcst efmn efcs## epos arch vrfy earc

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GFS Output - Dayfiles

Text output files containing details of run, as well as error messages for troubleshooting, found in $COMROT Naming convention:

$PSLOT$CDATE$CDUMP$CSTEP.dayfile

New Hybrid EnKF CSTEPs: • • • • •

echk* eobs eomn eomg## eupd

• • • • •

ecen efmn efcs## epos earc

* echk = epre

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GFS Output – New Hybrid EnKF Data

http://www.emc.ncep.noaa.gov/GFS/exp.php#All_files

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Documentation & Help

Website: http://www.emc.ncep.noaa.gov/GFS/exp.php

Listserv (Glopara Support): [email protected]

In Person: Stop by my cube next to the 2 nd breakroom  floor

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Questions?

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