Status of NCAR’s Data Assimilation Initiative (DAI) Report to NCAR Directors Committee 17 April, 2003 “DAI aims to create and lead a research community for data assimilation where individu- als benefit from sharing ideas, methodologies, and software tools as well as access to a data assimilation testbed.” “With a carefully controlled but rapid expansion of DAI, it should be possible for NCAR to be recognized as a leader in research data assimilation within 4 years (FY07).” Summary: On track, so far... /home/jla/dart/ncar_division_directors_mtg/presentation.fm April 18, 2003
History of DAI: Organization Nychka, Tribbia and Snyder formu- late DA plans Anderson on IPA to coordinate DAI Initiative Proposal prepared FY03 budget request and three year plan Sep. ‘01 Sep. ‘02 Sep. ‘03 /home/jla/dart/ncar_division_directors_mtg/presentation.fm April 18, 2003
History of DAI: Funding Anderson funded by NOAA FY01 Carryover, $67K FY02: $370K FY03: $700K Sep. ‘01 Sep. ‘02 Sep. ‘03 /home/jla/dart/ncar_division_directors_mtg/presentation.fm April 18, 2003
History of DAI: Personnel Nychka, Snyder, Tribbia (1/6) Anderson Tim Hoar (50%) Steve Aulenbach Dale Barker, Bill Skamarock,... (~25%) Kevin Raeder (80%) Alain Caya (new hire) Hui Liu (new hire) Sep. ‘01 Sep. ‘02 Sep. ‘03 /home/jla/dart/ncar_division_directors_mtg/presentation.fm April 18, 2003
Goals: DAI will provide: 1. A data assimilation community within NCAR to produce leading-edge research and to provide focus to disparate efforts; /home/jla/dart/ncar_division_directors_mtg/presentation.fm April 18, 2003
Goals: DAI will provide: 1. A data assimilation community within NCAR to produce leading-edge research and to provide focus to disparate efforts; 2. A software environment for supporting data assimilation research and evaluation; the Data Assimilation Research Testbed (DART); /home/jla/dart/ncar_division_directors_mtg/presentation.fm April 18, 2003
Goals: DAI will provide: 1. A data assimilation community within NCAR to produce leading-edge research and to provide focus to disparate efforts; 2. A software environment for supporting data assimilation research and evaluation; the Data Assimilation Research Testbed (DART); 3. A mechanism for data assimilation research collaboration with strategically selected partners from universities and government research labs; /home/jla/dart/ncar_division_directors_mtg/presentation.fm April 18, 2003
Goals: DAI will provide: 1. A data assimilation community within NCAR to produce leading-edge research and to provide focus to disparate efforts; 2. A software environment for supporting data assimilation research and evaluation; the Data Assimilation Research Testbed (DART); 3. A mechanism for data assimilation research collaboration with strategically selected partners from universities and government research labs; 4. Software tools for use in undergraduate and graduate education; /home/jla/dart/ncar_division_directors_mtg/presentation.fm April 18, 2003
Goals: DAI will provide: 1. A data assimilation community within NCAR to produce leading-edge research and to provide focus to disparate efforts; 2. A software environment for supporting data assimilation research and evaluation; the Data Assimilation Research Testbed (DART); 3. A mechanism for data assimilation research collaboration with strategically selected partners from universities and government research labs; 4. Software tools for use in undergraduate and graduate education; 5. Basic research and implementation support for ‘operational’ partners, both within NCAR and outside. /home/jla/dart/ncar_division_directors_mtg/presentation.fm April 18, 2003
Strategic Approach: Use DART (software infrastructure) to Focus Efforts 1. Cross-cutting initiatives in danger of becoming too diffuse (everything to everyone) 2. Strategy used successfully to coordinate modeling/dynamics groups (CCSM, MM5) /home/jla/dart/ncar_division_directors_mtg/presentation.fm April 18, 2003
Strategic Approach: Use DART (software infrastructure) to Focus Efforts 1. Cross-cutting initiatives in danger of becoming too diffuse (everything to everyone) 2. Strategy used successfully to coordinate modeling/dynamics groups (CCSM, MM5) What is DART? A. Allows combinations of assimilation algorithms, models, and observation sets B. Diagnostic tools for assimilation experimentation C. Set of compliant models, observational system designs, and observation sets /home/jla/dart/ncar_division_directors_mtg/presentation.fm April 18, 2003
Strategic Approach: Use DART (software infrastructure) to Focus Efforts 1. Cross-cutting initiatives in danger of becoming too diffuse (everything to everyone) 2. Strategy used successfully to coordinate modeling/dynamics groups (CCSM, MM5) What is DART? A. Allows combinations of assimilation algorithms, models, and observation sets B. Diagnostic tools for assimilation experimentation C. Set of compliant models, observational system designs, and observation sets Educational Applications D Basic Assimilation Research A R CAM, WRF, WACCM, .... T Universities, NCEP, labs /home/jla/dart/ncar_division_directors_mtg/presentation.fm April 18, 2003
Structure of Data CGD, CCSM MMM, WRF Ensemble Filter Development Assimilation Initiative for CAM Team, Ensemble Filter for WRF Affiliated Affiliated Scientist(s) Scientist(s) DAI Core Activities DAI Principal Scientists (Nychka, Snyder, Tribbia, Anderson) and Core Staff External Collaborator(s) External Collaborator(s) Goal: Identify set of meaningful MIT Atmos. NCEP, Devel. Sciences Division internal and exter- nal collaborations. Ensemble filter DA for Rotating Annulus for MRF /home/jla/dart/ncar_division_directors_mtg/presentation.fm April 18, 2003
DAI Provides: Expertise on Assim. Methodologies and Applications Software Infrastructure (DART) Basic Research Support Support for Core Scientists and Staff Collaborator Provides: Expertise on particular application Model or observational data sets Affiliated scientists with expertise on application /home/jla/dart/ncar_division_directors_mtg/presentation.fm April 18, 2003
DAI: Accomplishments and Plans 1. Data Assimilation Research Testbed (DART) Basic framework implemented Currently using GFDL FMS infrastructure Switch to ESMF infrastructure when available Primarily implementing ensemble (Kalman) filters Variational for low-order models only Plans MAY include a variational (4D-Var) capability DART compliant models (largest collection ever available with assim system) CGD’s CAM 2.0 GFDL FMS B-grid GCM incorporated and in use Many low-order models available MMM’s WRF model in process of being incorporated NCEP MRF being tested quasi-operationally in partial implementation GFDL MOM ocean model partially incorporated in earlier version /home/jla/dart/ncar_division_directors_mtg/presentation.fm April 18, 2003
DAI: Accomplishments and Plans 2. Supporting ASP Summer Colloquium on data assimilation DART will be used for student exercises 3. Hosting numerous data assimilation visitors Luc Fillion, Canadian Meteorological Center Jim Hansen, MIT Xiaolei Zou, FSU Ron Errico, NASA/DAO Shree Khare, Princeton Ryan Torn, U. Washington /home/jla/dart/ncar_division_directors_mtg/presentation.fm April 18, 2003
DAI: Accomplishments and Plans 4. An Ensemble Filter DA system for CGD’s CAM Testing underway at low resolution Standard T42 configuration also working Truth Ensemble Mean Analysis 8 8 260 260 7 7 Results from assimi- 250 6 6 lating only 1800 240 240 5 5 surface pressure 4 4 230 observations every 3 3 220 220 12 hours 2 2 1 1 5 10 15 5 10 15 Temperature at RMS ERROR = 0.61412 700mb shown 8 1 7 Mean error reduced 6 0 to about 0.6 C 5 4 3 −1 2 1 5 10 15 /home/jla/dart/ncar_division_directors_mtg/presentation.fm April 18, 2003
DAI: Accomplishments and Plans 5. DART filter being used for parallel tests in NCEP operational global model /home/jla/dart/ncar_division_directors_mtg/presentation.fm April 18, 2003
DAI: Accomplishments and Plans 6. Filter implemented for GFDL B-grid GCM Perfect model experi- ENSEMBLE MEAN PRIOR RMS TEMP ERROR (K) LEVEL 1 ment LEVEL 2 0.3 LEVEL 3 Assimilation of only LEVEL 4 LEVEL 5 surface pressure obser- 0.25 vations 0.2 RMS error for tempera- ture is plotted 0.15 Impact of increasing 0.1 observation frequency 0.05 1800 PS obs every 24 hours down to every 5 0 minutes 0 5 10 15 20 ASSIMILATION FREQUENCY, HOURS /home/jla/dart/ncar_division_directors_mtg/presentation.fm April 18, 2003
DAI: Accomplishments and Plans 7. Fundamental research on filtering data assimilation Ability to use limited observations Observation system simulations Localizing impact of observations (GSP Postdocs helping out here) 8. Incorporation of WRF into DART Compiling but untested Initial version available by summer 9. WRF / CAM integrated filter assimilation system Fundamental problem for regional models is boundary Use CAM assimilations for WRF boundaries Prototype for embedded regional models? Encourage CGD/MMM assimilation collaboration /home/jla/dart/ncar_division_directors_mtg/presentation.fm April 18, 2003
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