CFS reanalysis design

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Design and Execution of the 30-year NCEP CFSRR
T382L64 Global Reanalysis and T126L64 Seasonal
Reforecast Project(1979-2008)
Suru Saha and Hua-Lu Pan, EMC/NCEP With Input
from Stephen Lord, Mark Iredell, Shrinivas
Moorthi, David Behringer, Ken Mitchell, Bob
Kistler, Jack Woollen, Huug van den Dool,
Catherine Thiaw and many others
Updated 15 Jan 2008
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• CFSRR Advisory Board Members
• Chair Jeff Anderson (NCAR)
• Saki Uppala (ECMWF)
• Gabriel Lau (GFDL/NOAA)
• Eric Wood (U Princeton)
• Gil Compo (CDC/NOAA)
• Mark Serreze (U Colorado)
• Rick Rosen (CPO/NOAA)
• Huug van den Dool (CPC/NCEP)
• Jim Carton (U Maryland)
• Lars Peter Riishojgaard (JCSDA/NCEP)

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For a new Climate Forecast System (CFS)
implementation Two essential components A new
Reanalysis of the atmosphere, ocean, seaice and
land over the 31-year period (1979-2009) is
required to provide consistent initial conditions
for A complete Reforecast of the new CFS over
the 28-year period (1982-2009), in order to
provide stable calibration and skill estimates of
the new system, for operational seasonal
prediction at NCEP
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• For a new CFS implementation (contd)
• Analysis Systems Operational GDAS Atmosphe
  ric (GADAS)-GSI Ocean-ice (GODAS)
  and Land (GLDAS)
• 2. Atmospheric Model Operational GFS
• 3. Ocean Model New MOM4 Ocean
• 4. Land Model Operational Noah Land Model
• 5. Sea Ice Model New Sea Ice Model

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• An upgrade to the coupled atmosphere-ocean-seaice-
  land
• NCEP Climate Forecast System (CFS) is being
  planned for 2010.
• This upgrade involves changes to all components
  of the CFS, namely
• improvements to the data assimilation of the
  atmosphere with the new NCEP Gridded Statistical
  Interpolation Scheme (GSI) and major improvements
  to the physics and dynamics of operational NCEP
  Global Forecast System (GFS)
• improvements to the data assimilation of the
  ocean and ice with the NCEP Global Ocean Data
  Assimilation System, (GODAS) and a new GFDL MOM4
  Ocean Model
• improvements to the data assimilation of the land
  with the NCEP Global Land Data Assimilation
  System, (GLDAS) and a new NCEP Noah Land model

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• For a new CFS implementation (contd)
• An atmosphere at high horizontal resolution
  (spectral T382, 38 km) and high vertical
  resolution (64 sigma-pressure hybrid levels)
• An interactive ocean with 40 levels in the
  vertical, to a depth of 4737 m, and high
  horizontal resolution of 0.25 degree at the
  tropics, tapering to a global resolution of 0.5
  degree northwards and southwards of 10N and 10S
  respectively
• An interactive sea-ice model
• An interactive land model with 4 soil levels

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• There are three main differences with the earlier
  two NCEP Global Reanalysis efforts
• Much higher horizontal and vertical resolution
  (T382L64) of the atmosphere (earlier efforts were
  made with T62L28 resolution)
• The guess forecast will be generated from a
  coupled atmosphere ocean seaice - land
  system
• Radiance measurements from the historical
  satellites will be assimilated in this Reanalysis
• To conduct a Reanalysis with the atmosphere,
  ocean, seaice and land coupled to each other will
  be a novelty, and will hopefully address
  important issues, such as the correlations
  between sea surface temperatures and
  precipitation in the global tropics, etc.

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UPGRADES TO THE ATMOSHERIC MODEL

• Hybrid vertical coordinate (sigma-pressure)
• Noah Land Model 4 soil levels. Improved
  treatment of snow and frozen soil
• Sea Ice Model Fractional ice cover and depth
  allowed
• Sub grid scale mountain blocking
• Reduced vertical diffusion
• RRTM long wave radiation
• ESMF (3.0)

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UPGRADES TO THE ATMOSHERIC MODEL

• Enthalpy
• AER RRTM Shortwave Radiation
• New Aerosol Treatment
• Inclusion of historical CO2, solar cycle and
  volcanic aerosols

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• 6 Simultaneous Streams
• Jan 1979 Dec 1985 7 years
• Nov 1985 Feb 1989 3 years
• Jan 1989 Feb 1994 5 years
• Jan 1994 Dec 1998 5 years
• Apr 1998 Dec 2004 6 years
• Apr 2004 Dec 2009 5 years
• Overlap for ocean and land spin ups
• Reanalysis to cover 31 years (1979-2009)

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ONE DAY OF REANALYSIS
12Z GSI
18Z GSI
0Z GSI
6Z GSI
0Z GLDAS
12Z GODAS
18Z GODAS
0Z GODAS
6Z GODAS
9-hr coupled T382L64 forecast guess (GFS MOM4
Noah)
1 Jan 0Z
2 Jan 0Z
3 Jan 0Z
4 Jan 0Z
5 Jan 0Z
5-day T126L64 coupled forecast ( GFS MOM4
Noah )
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ONE DAY OF REANALYSIS

• Atmospheric T382L64 (GSI) Analysis at 0,6,12 and
  18Z, using radiance data from satellites, as well
  as all conventional data
• Ocean and Sea Ice Analysis (GODAS) at 0,6,12 and
  18Z
• From each of the 4 cycles, a 9-hour coupled
  guess forecast (GFS at T382L64) is made with
  hourly coupling to the ocean (MOM4 at 1/4o
  equatorial, 1/2o global)
• Land (GLDAS) Analysis using observed
  precipitation with Noah Land Model at 0Z
• Coupled 5-day forecast from initial conditions
  from every 0Z cycle, will be made with the
  T126L64 GFS with hourly coupling to the ocean
  (MOM4 at 1/4o equatorial, 1/2o global) for sanity
  check.

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T382L64 CFS REANALYSIS AND 5-day T126L64 FORECASTS
IBM Power 5
Approximately 7 days of T382L64 Reanalysis, including a 5-day T126L64 forecast every cycle, for each of the 6 simultaneous streams 40 CFSR days in 1 calendar day with 82 nodes Will take 1 calendar year to complete 34 years (on HAZE upgrade)
Total Disk Space 104 TB
Total Mass Store (HPSS) Space 1.5 PB
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Collaborators

• NOAA/CPC is actively involved in the monitoring
  of the Reanalysis
• NOAA/NCDC is actively involved in the design of
  the data distribution of the Reanalysis

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37 Pressure (hPa) Levels pgb, egy and diab
(atmosphere) 1000 975 950 925 900 875 850 825 800
775 750 700 650 600 550 500 450 400 350 300 250
225 200 175 150 125 100 70 50 30 20 10 7 5 3 2
1 40 Levels (depth in meters) ocn (ocean) 4478
3972 3483 3016 2579 2174 1807 1479 1193 949 747
584 459 366 303 262 238 225 215 205 195 185 175
165 155 145 135 125 115105 95 85 75 65 55 45 35
25 15 5 16 Isentropic Levels (K) ipv 270 280
290 300 310 320 330 350 400 450 550 650 850 1000
1250 1500
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CDAS (R1) GFS AM (OPR)
Vertical coordinate Sigma Sigma/pressure
Spectral resolution T62 T382
Horizontal resolution 210 km 35 km
Vertical layers 28 64
Top level pressure 3 hPa 0.266 hPa
Layers above 100 hPa 7 24
Layers below 850 hPa 6 13
Lowest layer thickness 40 m 20 m
Analysis scheme SSI GSI
Satellite data NESDIS temperature retrievals Radiances
Moorthi, Nov 2007
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• DATA STUDIES
• We have made 20 data impact studies (using T62L64
  atmospheric-only data assimilation system)
• We have tested SSU, ERS winds, JMA reprocessed
  cloud track winds, and PAOBS
• We have tested the new Reynolds ¼ degree SST for
  the GODAS
• We have tested the new 0.5 degree global CPC
  precipitation product for the GLDAS
• We have updated snow and sea ice
• We have collected tropical storm information from
  ERA40 and from our own archive
• We have done several satellite radiance bias spin
  up experiments and are continuing to do them

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• MONITORING
• Monitoring Web site has been built
• The CPC team has done an outstanding job of
  monitoring the
• Stratosphere
• Troposphere
• Surface
• Ocean
• EMC monitoring of data usage and verification of
  the 5-day short range forecasts is also underway

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OPR
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CFSR
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OPR
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CFSR
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5 day scores in CFSRR are better in NH than in SH
in 1979.
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Increasing satellite data in later years have
made the scores in NH and SH more comparable
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A QBO Problem
10 hPa ZONAL WIND RAWINDSONDE AT SINGAPORE OBS
(red), ANALYSIS (green) GUESS (blue)
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After changes to the background error covariances
10 hPa ZONAL WIND RAWINDSONDE OBS AT SINGAPORE
(red), ANALYSIS (green) GUESS (blue)
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SOME PROBLEMS FACED DURING THE SPIN UP PHASE OF
CFSR

• MANY BUG FIXES IN CODES AND SCRIPTS
• ADEQUATE COMPUTER RESOURCES NOT RECEIVED UNTIL
  JULY 1.
• ADEQUATE FUNDING NOT RECEIVED UNTIL JULY 1.
• DUE TO THIS, CFSR DELIVERY DATE HAS SLIPPED
• A QUARTER OF THE PROJECT IS DONE

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THE HUMAN FACE OF CFSR
Diane Stokes Hui-ya Chuang Mark Iredell Jesse
Meng Ken Mitchell Russ Treadon Daryl Kliest Glenn
White Yu-Tai Hou Steve Lord Helin Wei Bob
Grumbine George Gayno Jun Wang Paul van Delst
Suru Saha Xingren Wu Jiande Wang Patrick
Tripp Sudhir Nadiga
CPC/EMC MONITORING
Hua-Lu Pan Shrinivas Moorthi Bob Kistler Jack
Woollen Haixia Liu Dave Behringer
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CPC/EMC SCIENTISTS MONITORING CFSR
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Issues

• Integrated Earth System Analysis
• Aerosol is in the plan for the operational data
  assimilation system and will be available at the
  next CFSRR
• CO2 changes are already built in the current CFS
  Reanalysis
• 20-century type of CMIP runs indicates that the
  CFS in the CFSRR system is capable of responding
  to the CO2 changes
• How can we accelerate the future CFSRR?
• Data assimilation combine satellite radiance
  usage with the earth system modeling to address
  atmosphere, ocean, land, ice, and biosphere
• Improving both weather and climate signals in the
  fully coupled models
• Resource needed to do both

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Email cfs_at_noaa.gov Website
http//cfs.ncep.noaa.gov