Data Assimilation Testbed Center (DATC)


  • About DATC
  • DATC Projects
  • References
  • Contacts

Welcome to the homepage for The Data Assimilation Testbed Center (DATC). The DATC was established within RAL's Joint Numerical Testbed in August 2006 to provide an environment for the objective testing and evaluation of state-of-the-art data assimilation techniques as applied in real-world numerical weather prediction applications. The DATC is also intended to complement the activities of the Developmental Testbed Center (DTC) by providing support, testing and evaluation of the data assimilation component of the Weather and Research Forecasting (WRF) modeling system.

The current scope of the DATC includes:

  • Data assimilation technique testing and evaluation (variational, ensemble, hybrid, nudging).
  • Data assimilation inter-comparison (GSI, WRF-Var, ...).
  • Observation System Experiments (OSEs).
  • Observation System Simulation Experiments (OSSEs).
  • Observation impact study.
  • Observation and background error estimation and tuning.
  • Data assimilation system maintenance and community support.
  • NWP system, including forecast and data assimilation system, pre-release/pre-operational extended testing.
  • NWP system sensitivity study (cycling vs cold-start, frequency, resolution, ...)
  • Data assimilation based validation and quality control.

The scope of the DATC is evolving as new applications appear.

An illustration of the role of the DATC as a bridge between WRF DA research and operational communities.

DATC Projects

The DATC was initiated as a joint collaboration between NCAR and the Air Force Weather Agency (AFWA) in 2006. Since then, the DATC has become an international effort supported by AFWA, NCAR's Antarctic Mesoscale Predictions System (AMPS), the Korean Meteorological Administration (KMA) and Taiwan Civil Aeronautics Administration (CAA). Testbeds have been built to test and evaluation data assimilation components in various applications.

    AFWA Testbed

    Given its unique mission, AFWA focuses on high-resolution, multi-theater and worldwide numerical weather predications. One emphasis of the DATC is to ensure AFWA's data assimilation and forecasting systems are thoroughly tested to match its unique set of requirements. In various domains, the DATC is conducting an extensive series of experiments to evaluate alternative data assimilation techniques (e.g. WRF-Var, GSI, Hybrid Ensember/Var, etc.) and forecast impacts of various observations (e.g. radio occultation observations, radiance data, etc.).

    AMPS Testbed

    The Antarctic Mesoscale Prediction System (AMPS) is an experimental, real-time, high-resolution numerical weather prediction capability for the United States Antarctic Program (USAP). It includes the WRF-ARW dynamic solver and the three-dimensional WRF-Var data assimilation (DA) system. The system is running in real-time at NCAR/MMM. The major goal of the DATC AMPS Testbed is to support data assimilation efforts in this system. The current work is as follows: (a) keeping the AMPS DA system up to date; (b) tuning the background error covariances for AMPS; and (c) evaluating and, therefore, ingesting of new satellite observations into AMPS.

    CAA Testbed

    The Taiwanese Civil Aeronautics Administration (CAA) Testbed is a pre-operational test-rig to evaluate the CAA WRF-ARW and WRF-Var system in Pacific applications. Major work includes studies of radio-occultation data impacts, radiance data assimilation tuning, and radiance data impacts on typhoon forecasts, etc. > more

    KMA Testbed

    The Korean Meteorological Administration (KMA) Testbed features embedded domains with10-km and 3.3-km horizontal resolutions. The major focus of the DATC work is to test the capabilities of the KMA WRF-ARW and WRF-Var system in extended runs, investigate high-impact weather DA (e.g., radar DA), and conduct DA configuration tuning (resolution, cycling vs cold-start mode of the system).

    Indian Domain Testbed

    The Indian Domain Testbed explores the use of WRF NMM dynamic solver with both the NCEP's operational GSI data assimilation system and the NCAR's WRF-Var data assimilation system for the forecast of tropical cycling track and intensity over Bay of Bengal.


  • Applications of WRF Data Assimilation System at the NCAR Data Assimilation Testbed Center, The 9th WRF Users' Workshop, June 24-27, 2008, Boulder, Colorado (pdf)

Related links

Forecast and Data Assimilation Systems: