CTB computer resources / CFSRR project

1. CTB computer resources /CFSRR project Hua-Lu Pan

2. Computer resource for the CTB - 2007 • 30% of the NCEP component of the NOAA R & D computer is dedicated to the CTB • This comes to 400 processors (IBM power 5) • In 2007, only two externally funded projects used the CTB computer • CTB internal Transition Project Team made use of the rest of the CTB computing resource

3. Computer resource plan for 2008 and future • It is envisioned that more and more of the future CTB computer resource will be dedicated to the externally funded CTB projects • In 2008, there will be a few more externally funded projects on the CTB computer • A special project for 2008

4. To accelerate the implementation of the next CFS • Most of the funded CTB work will likely contribute to the n+1 version of the CFS • EMC is requesting 224-240 of the 400 processors for the CFSRR project. This will provide 20 percent of the needed resource to run the CFSRR. The rest of the computing resource will be from NCEP CCS • There should be sufficient processors left for the externally funded CTB projects upon review of the LOIs • This is for 2008 only.

5. Design 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 others

6. An upgrade to the coupled atmosphere-ocean-seaice-land • NCEP Climate Forecast System (CFS) is being planned for Jan 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 Landmodel

7. 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 29-year period (1981-2009), in order to provide stable calibration and skill estimates of the new system, for operational seasonal prediction at NCEP

8. For a new CFS implementation (contd) • Analysis Systems : Operational DAS: Atmospheric (GSI) Ocean (GODAS) and Land (GLDAS) • 2. Atmospheric Model : Operational GFS • New Noah Land Model • 3. Ocean Model : New MOM4 Ocean Model • New SEA ICE Model

9. For a new CFS implementation (contd) • An atmosphere at high horizontal resolution (spectral T382, ~35 km) and high vertical resolution (64 sigma-pressure hybrid levels) • An interactive ocean with 40 levels in the vertical, to a depth of 4737 km, 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

10. 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.

11. Current plan • Begin the reanalysis in January 2008 and complete in one year • 2. We plan to use four streams with six-month overlap • 3. Computer resource is an issue. Currently making internal NCEP resource request due to a delay in the upgrade of the NOAA R&D computer • 4. Working with NCDC to provide data to users

12. NCDC Archive for CFSRR • Dataset Volume: • Approaching 400TB. • Limited resources. • Prioritization of archive data sets in process. • Access: NOMADS Data Distribution System • NCDC and NCEP planning for access via NOMADS Web Services using a Services Orientated architecture. Similar experiences servicing NARR, Global Reanalysis. • National Academies BASC recommends advancing NOMADS for “…ensembles and reforecast…” datasets. • Contributing to TIGGE-1 , candidate Phase-II archive. • Community Meeting: • NCEP, NCDC, NASA, COLA, CPO et al., to discuss data input and process for CFSRR and subsequent reanalysis. G. Rutledge NCDC

13. 4 Simultaneous Streams • Oct 1978 – Sep 1986 8 years • Apr 1986 – Oct 1993 7 1/2 years • Apr 1993 – Oct 2000 7 1/2 years • Apr 2000 – Dec 2009 10 years 6 month overlap for ocean and land spin ups Total of 31 years (1979-2009) + 21 overlap months

14. Current Plan PROPOSED TIME LINE FOR COMPLETION OF CFSRR • January to December 2008: Begin and complete Production and Evaluation of the CFS Reanalysis for the full period from 1979 to 2008 (30 years) • January to December 2008: Running and evaluating CFS Retrospective Forecasts for 2 initial months: October and April, and evaluate the monthly forecasts as well as the seasonal winter (Lead-1 DJF) and summer (Lead-1 JJA) forecasts. • January to October 2009: Continue running the CFS Reforecasts (for the rest of the 10 calendar months) • November 2009: Begin computing calibration statistics for CFS daily, monthly and seasonal forecasts. • January 2010: Operational implementation of the next CFS monthly and seasonal forecast suite.