COASTAL Act Challenges for
Post-Assessments of “Named Storms”
April 4, 2013
S. Lord (NWS/OST)
M. Bilder (NWS/OSPP)
M. Powell (OAR/AOML/HRD)
J. Feyen (NOS/OCS/CSDL/MMAP)
A. Westhuysen (NWS/NCEP/EMC)
T. Owen (NESDIS/NCDC)
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Presentation Topics
• Background summary
• Observations
• Challenges
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Background
Summary
• Consumer Option for an Alternative System to
Allocate Losses (COASTAL) Act signed 6 July
2012.
– Intended to lower costs to FEMA’s National Flood Insurance
Program
– Focus: improve determination of wind vs. water damage in
cases of “indeterminate losses” (or “slab cases”).
• NOAA required to produce
– Detailed “post-storm assessments” [analyses]
– Criteria for “named storms”
•
•
•
•
Defined surface circulation
Maximum winds of at least 39 miles per hour
Named as Tropical Storm or Hurricane by National Hurricane Center
Designated by NOAA and DHS as posing a “significant threat”
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Available Observations for Hurricane Irene
27 August 2011 10 UTC (1 h window)
Routine Conventional Observations
Max wind 82 kt; Cape Hatteras ASOS
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Available Observations for Hurricane Irene
27 August 2011 10 UTC (1 h window)
Routine Conventional Observations
Weather Flow and Texas Tech “Sticknet”
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Available Observations for Hurricane Irene
27 August 2011 10 UTC (1 h window)
Routine Conventional Observations
Weather Flow and Texas Tech “Sticknet”
Aircraft Recon (Doppler, flight level)
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The Challenges:
Observations and Analysis
• Observations
– Surface observation density not high enough to support wind analyses at
high accuracy
– Water level observation network also insufficiently dense
– Lack of required coverage and accuracy of bathymetric and topographic
data
• Software integration
– Transition of existing software, owned by various NOAA LOs, to integrated
system adapted for post-analysis
– Continued development and consolidation of current software capabilities
• Response capability
– Conducting post-storm assessments within 90 days at high level of impact
detail
– Any future requirements (e.g. extra-tropical storms)
• Computational resources
– System integration
– Testing on historical cases
– Continued development
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Supplementaries
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NSEM Software Candidates
• Wind
– H*Wind analysis
– Real-Time Mesoscale Analysis (RTMA)
– Hurricane WRF (HWRF)
• Storm Surge/Waves
– Advanced Circulation (ADCIRC) model
– Nearshore Wave Prediction System (NWPS, Wavewatch III)
– SLOSH
• Precipitation
– RTMA (NWS/RFC Stage II)
– Multiple-Radar Multiple Sensor (MRMS) analysis
• Riverine flooding/runoff
– NWS/OHD Hydrologic Engineering Center River Analysis System
(HEC-RAS from USACE)
– USACE Gridded Surface Subsurface Hydrologic Analysis (GSSHA)
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Background
NOAA Partners
•
NOAA Team
– NWS
•
Office of Science & Technology (OST, incl. Meteorological Develop Laboratory)
•
National Centers of Environmental Prediction (EMC)
•
Office of Hydrological Development (OHD)
•
Office of Climate, Weather & Water Services (OCWWS)
•
Office of Strategic Planning and Policy
– NOS
•
Office of Coast Survey
•
Coastal Services Center
•
Integrated Ocean Observing System Program
•
Policy, Planning & Analysis Division
– OAR
•
–
Atlantic Oceanographic & Meteorological Lab (Hurricane Research Division, HRD)
NESDIS
•
National Climatic Data Center (NCDC)
•
National Geophysical Data Center (NGDC)
– Also consulting with NOAA OGC and OLIA on legal and congressional matters.
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Background
Interagency Partners
• Office of the Federal Coordinator
– Joint Action Group for the COASTAL Act Post-Storm Analysis
(JAG/CAPSA, est. Sept. 2012 with multi-agency co-chairs)
•
Taking lead on drafting the data collection plan due to Congress in April 2013.
•
Mandated inventory of available observing systems and requirements (Oct. 2012)
•
Identified (through RFI) all Federal, state, private and academic efforts and systems capable of collecting
“covered data”, including private data suppliers (Jan. 2013)
• FEMA must develop the COASTAL Formula
– A standard recipe to determine and allocate wind losses and flood
losses for claims involving indeterminate losses
– Developed in consultation with NOAA
• NAS will evaluate the formula’s effectiveness
• GAO must audit NOAA’s data collection efforts, including the
cost-effectiveness of the approach
• Community-based Subject Matter Experts
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Named Storm Event Model (NSEM)
• Collection of separate, but interdependent, gridded products
– Provide time-dependent analyses of specific meteorological, oceanographic
and hydrodynamic factors contributing to indeterminate losses
– Analysis and hindcast gridded products derived from observations
• Products will cover 4 primary risk areas:
– Wind and surface pressure (including embedded severe/ convection
events)
– Storm Surge/Waves
– Precipitation (including impact on Riverine domain)
– Riverine Flooding/Runoff
• Input from highest resolution bathymetric and topographic data is
essential
• Validating accuracy (90% criterion from COASTAL Act)
– Meeting accuracy requirements will be a major challenge
– Bootstrapping technique is likely
– Considers variability and uncertainty of analysis verification and techniques
for analyses produced from
• Independent sub-samples of total observations and ratios of variability to mean
analyzed quantity (e.g. wind speed)
• Different techniques valid within the scope of current knowledge and practice
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Comments on NSEM Software
Development Strategy –
Major Components
• Wind
– None of the existing software candidates is fully capable of
meeting Coastal Act requirements
– Accuracy depends on
• Observation distribution (coverage and density)
• Processing (e.g. height adjustment)
• Analysis technique
• Surge/Wave
– Include tidal component
– Unstructured grid coupling under development
– Untested as coupled software package
• Precipitation and Riverine flooding
– Less frequent cause of indeterminate loss
– Less well developed at this time
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Comments on NSEM Software
Development Strategy –
Connecting the Pieces
• System integration and evaluation
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–
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Arbitrary domain for each storm (portability)
I/O dependencies (coupling the pieces)
Error propagation (wind  surge/wave)
Evaluation and “high bar” for accuracy
Transition from prediction (ops) to post-analysis
• Collaborative development process using
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–
–
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Common observations
Merged software capabilities
Ensemble techniques
Error analysis procedures
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