zoltan toth environmental modeling center noaa/nws/ncep acknowledgements:
DESCRIPTION
Zoltan Toth Environmental Modeling Center NOAA/NWS/NCEP Acknowledgements: Aimee Devaris, Sreela Nandi, Fred Toepfer, Marty Ralph, John Gaynor, Paul Hirschberg, Yuejian Zhu http://wwwt.emc.ncep.noaa.gov/gmb/ens/index.html. - PowerPoint PPT PresentationTRANSCRIPT
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PLANS FOR PROBABILISTIC GUIDANCE PRODUCTS FOR HIGH IMPACT EVENTS &
CORRESPONDING PERFORMANCE MEASURES
Zoltan Toth
Environmental Modeling CenterNOAA/NWS/NCEP
Acknowledgements:Aimee Devaris, Sreela Nandi, Fred Toepfer, Marty Ralph, John
Gaynor, Paul Hirschberg, Yuejian Zhu
http://wwwt.emc.ncep.noaa.gov/gmb/ens/index.html
NOAA PLANNING, PROGRAMMING, BUDGETING AND EXECUTION SYSTEM (PPBES FY2010-14)
PROBABILISTIC NUMERICAL GUIDANCE FOR HIGH IMPACT EVENTS
• Goal: Provide highest quality, coordinated, and seamless probabilistic automated guidance products, including information on forecast uncertainty
• Deliverable: Comprehensive suite of ensemble forecast systems (“forecast engine”) that facilitate the generation of automated forecast guidance as a basis for high impact event forecasting for NOAA operations regarding high impact events
• Range of use: All high impact weather, water, and climate forecast applications
• Motivation: Need unified approach for ease of implementation, maintenance, and use, where scientifically possible / justified; THORPEX concepts generalized in NFUSE process; linked with NUOPC
• Supporting programs: STI & EMP
PROGRAM DESCRIPTION (PNGHIE)
• Time/spatial scales: All spatial and time scales, including – Now-casting (6-12 hrs, local scale modeling)– Short range (up to 3 days, regional modeling)– Medium- and extended range (up to 15 days, global modeling)– Sub-seasonal (10-60 days, coupled global ocean / land surface /
atmosphere modeling)– Seasonal (2-12 months, coupled global OLA modeling)
• New aspects of forecast process– Integrated from observations to user applications– Focused on high impact events– Probabilistic to capture forecast uncertainty– Seamless guidance from minutes to seasons– Adaptive to provide best case dependent info– User controllable to cater to users’ needs
PROGRAM DESCRIPTION (PNGHIE)
• Scope / participants:– Applied research - External community: THORPEX AOs, OAR Labs
– Transition to operations - NCEP/EMP
– Operations - NCEP/NCO, NCDC
PROGRAM ACTIVITIES (PNGHIE)
• Design of observing system for high impact events– Development of observing instruments/platforms to fill gaps in current system
– Optimal design of satellite & in-situ observing network
– Adaptive collection and processing of observations
• Advanced data assimilation techniques– Ensemble-based forecast error covariance
– Initial ensemble perturbations
• Numerical modeling for high impact events– Ensemble techniques for high impact applications
• Air quality/dispersion, tropical cyclones, extra-tropical storms, fire weather, etc
– Model-related uncertainties in ensemble forecasting
– Variable-resolution modeling for high impact events
• Socio-economic applications– Statistical bias correction (lead time dependent errors)
– Downscaling (fine resolution information)
– Combination of all forecast information
– Product generation
– User applications (Decision Support Systems)
DRIVERS
• External– National Research Council (NRC) Report
• Completing the Forecast: Characterizing and Communicating Uncertainty for Better Decisions Using Weather and Climate Forecasts
– Recommendation for NOAA/NWS to become leader in the development and use of probabilistic and ensemble forecast methods within weather/water/climate enterprise
– National Unified Operational Prediction Capability (NUOPC)• Tri-agency (NOAA, US Navy, US Air Force) effort at unified probabilistic global
prediction capability– Multi-center ensemble forecasts at its core (extension of NAEFS, linked with TIGGE / GIFS)
• Internal– NOAA AGM FY2010-14 PRIORITIES
• Twelve references to improved and extended ensemble, probabilistic numerical guidance for high impact events
– NWS Forecast Uncertainty Service Evolution (NFUSE) Team• Probabilistic Numerical Guidance is one of three major areas coordinated under
NFUSE:– “Human factor” – How numerical forecasts are improved and communicated by human
forecasters
– Outreach – What products the external user community needs, and how they use them
COORDINATION WITH OTHER PROGRAMS• NWS Forecast Uncertainty Service Evolution (NFUSE) Steering Team
– Probabilistic Guidance for high impact events will be communicated to, and modified by human forecasters; final, official numerical ensemble guidance will be made available for use by general public and special users
• W&W – LFW– Distribution, manipulation, display, depository, verification of ensemble forecast
data, training of forecasters
• W&W – STI– Provides: Observing instruments and platforms, decision support tools, outreach
to external users
– Receives: Probabilistic/ensemble guidance for HMT demo projects
• Water resources - Hydrology • Climate Goal – Predictions and Projections Program
– Weather-Climate connections, Sub-seasonal and seasonal forecasting
• Climate Goal - Climate Observations and Analysis (COA) Program– Archive and distributed web services access to ensemble forecasts though the
NOAA National Operational Model Archive and Distribution System (NOMADS)
• Building Community Resilience in the Face of Coastal Hazards – Provides: Critical application area for probabilistic forecast activities
– Receives: Early numerical warning for high impact events
PERFORMANCE MEASURES FOR NEWPROBABILISTIC GUIDANCE
• No official NWS requirement exists for probabilistic products– In practice, isolated examples within NWS– NFUSE will coordinate proposed change in official requirements to include
forecast uncertainty / probabilistic information?• Consider NRC recommendations, along with examples within & outside NWS• Draft in half year, full proposal in a year?
• Technical question of what measures to use for assessing skill associated with new requirements– Consider broad literature, existing practice within/outside NWS
• Draw on technical expertise within NWS & NOAA– Half year effort, can be done after or along development of requirements
• Plan for systematic introduction of “Probabilistic numerical guidance for high impact events”– POP under EMP, to be coordinated within NFUSE
• How to define performance measures?– Use more general language now, refer to plan for developing detailed requirements and
associated measures?
PERFORMANCE METRICS DISCUSSION
• Start discussion for planning period FY2010-14– Performance measures for numerical guidance must be also relevant for LFW
• Bridge / connecting point between EMP & LFW
• What needs to be done?– Design new products, define corresponding measures– Identify “legacy” scores with long record
• Procedure– Select type of products to be highlighted in performance measures– Discuss probabilistic measures
• Need metric that measures both– Statistical reliability
» Related to systematic errors– Statistical resolution
» Related to random errors
– Define details later for both products & metrics
• Application– Evaluation of bias corrected ensemble-based numerical guidance on model grid– Evaluation of downscaled probabilistic numerical guidance on NDFD grid
PROPOSED NEW / LEGACY PRODUCTS TO BE MONITORED• Possible new probabilistic guidance products for high impact events
– Hydrometeorology• Extreme hydro-meteorological events, incl. dry and wet spells (CONUS)• Quantitative extreme river flow forecasting (OCONUS)
– Tropical / winter storm prediction• Extreme surface wind speed• Extreme precipitation (related to wet spells)• Storm surges
– Aviation forecasting• Flight restriction• Icing, visibility, fog, clear air turbulence
– Health and public safety• Hot and cold spells
• “Legacy” internal probabilistic scores to assess long-term progress• With years of existing archive and/or • Can be easily recomputed
– General circulation• Probabilistic 1000 & 500 hPa height forecasts
– Tropical storm • Strike probability for track• Probability of intensity (central pressure or wind-based)