Climate Reanalysis Task Force Technical Workshop
NOAA Climate Reanalysis Task Force Technical Workshop
NCWCP Conference Center
5830 University Research Court
College Park, Maryland
Organizers: Jim Carton, Gilbert Compo, Arun Kumar, Suru Saha, Heather Archambault
Workshop Report (OAR Technical Report)
Agenda & Presentations || Participants || Logistics
The goal of retrospective data assimilation or “reanalysis” is to combine disparate observations into physically consistent estimates of the past state of the Earth system and its components, e.g., ocean, atmosphere, waves, land, cryosphere, and ionosphere, with quantified uncertainties. Reanalyses spanning the instrumental record of each component are an important requirement for climate monitoring and advancing predictive understanding, whether for determining the effects of changing boundary conditions and composition, or for providing initial conditions for retrospective forecasts. For almost 40 years, the availability of reanalyses has led to advances in understanding and predicting weather and climate variability, from extreme events to centennial trends. NOAA has been and continues to be an important contributor in the progress towards this goal.
Recent developments across NOAA, in partnership with universities and international agencies, are accelerating improvements to achieve this goal. The NOAA Climate Reanalysis Task Force (NCRTF) is charged with coordinating relevant research activities funded by the Climate Program Office and is focused on advancing reanalysis towards monitoring and understanding of climate variability. Additionally, NOAA advances in prediction from minutes to seasons require reanalyses spanning many years to serve as initial conditions and verifications for reforecasts that help quantify predictability and improve forecast skill.
As part of the weather and climate prediction enterprise, research improving models, data assimilation systems, and historical observational databases leads to improved reanalysis datasets generated regularly with increasing fidelity for all of the Earth System components. The NCRTF workshop will highlight advancements in these areas across NOAA, university and international efforts, identify gaps, and improve coordination of future activities to meet the requirements of the diverse array of users of reanalyses. Multiple strategies and a hierarchy of reanalysis datasets may be needed to maximize fidelity for specific requirements. Discussion of such strategies will also be a focus of the workshop. A two day series of presentations and vigorous discussion of NCRTF activities, related developments in NCEP weather and climate forecasting systems, and international efforts in these areas will strengthen NOAA’s and partner organizations’ development and utilization of these important datasets. A NOAA OAR Technical Report summarizing discussions and ways forward will be produced.
Proposed discussion areas:
- Identify the various requirements for reanalysis products.
- Identify gaps in NOAA and international reanalysis plans, algorithm development, and coordination in meeting these requirements.
- Exchange approaches, algorithms, and techniques currently in use and under development.
- Determine observational needs and gaps, and identify areas for national and international coordination.
- Determine strategies and overlaps for national and international reanalysis efforts based on scientific drivers for climate and weather research.
- Discuss advantages and disadvantages of a single reanalysis meeting multiple requirements.
- Outline algorithms and techniques for ways to meet multiple requirements, such as a hierarchy or “family” of reanalyses.
- Discuss techniques for addressing outstanding issues in the reanalysis efforts, e.g., presence of spurious discontinuities and trends, coupling of Earth System components, inclusion of new areas such as aerosols and atmospheric chemistry.