Advanced Hurricane Prediction

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Advanced Hurricane Prediction A plan for research
and development


Naomi Surgi February, 2005
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Requirements Process

• Societal Impacts
• More people living along coastal areas takes
  longer to evacuate
• Evacuations are costly 1M per mile of
  coastline evacuated
• Evacuation numbers depend on hurricane size and
  intensity
• More hurricane related fatalities now due to
  inland flooding

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Stakeholder Requirements

• Improved track forecast skill where and when?
• Extend track forecasts out to 5 days
• Improved hurricane intensity forecasts
• intensity at landfall how strong?
• onset of gale force winds at coastline
  (structure) how big when?
• Skillful heavy rainfall forecasts out to 3 days
  in advance

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Operational TC Forecast Issues

• Continued advancement of TC track forecasts
• Improved TC intensity prediction (genesis and
  rapid intensification)
• Improved prediction of TC surface wind
  distribution (structure)
• Improved rainfall forecasts
• TC waves, storm surge

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TPC Atlantic 72-hr Track Forecast Errors
With the exception of erratically moving
storms, while hurricane track prediction has
shown remarkable progress, skill in predicting
intensity/ structure changes is still poor. It is
expected that high resolution, advanced NWP
modeling systems may continue to improve track
as well as intensity, structure predictions.
Hurricane WRF is the next step towards this goal.

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Lowest track errors on record for GFS, GFDL
models and TPC!
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How NOAA Improved Track Forecasts
Three components of modeling system

• HIGH QUALITY OBSERVATIONS (large scale
  environment surrounding hurricane, e.g.
  satellite, aircraft)
• MADE BETTER USE OF OBSERVATIONS IN HURRICANE
  MODELS (advances in data assimilation)
• IMPROVED HURRICANE MODELS (improved numerical
  techniques and representation of physical
  processes)

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Advanced Data Platforms for Hurricanes

• Environment (Winds, Moisture, Temperature) to
  define steering currents
• Satellite Advanced Satellite Instruments
• (AMSU, GOES, NPOESS etc.)
• In-situ Aircraft (dropsondes)

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NCEP Global Forecast System 6 hr Forecast and WV
Imagery
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Jung and Zapotocny JCSDA Funded by NPOESS IPO
Satellite data 10-15 impact
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Synoptic Surveillance Pattern
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Impact Of Dropsondes On NCEP Global Model Track
Forecasts
Note Improved skill at all forecast times in
2002 and 2003
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Intensity Guidance
Most skill
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Charley deepened From 964 mb to 941 mb in 4 h 35
min near landfall NIGHTMARE!
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Science Issues to address Intensity/Structure

• ENVIRONMENTAL FORCING
• good vs. bad trough interactions
• SST changes (including ocean subsurface)
• CONVECTIVE SCALE PROCESSES
• total rainfall organization of convection,
  eyewall vs. Stratiform
• MICROPHYSICS LIQUID VS. ICE
• INNER CORE REGION
• scale interaction feedback between vortex
  dynamics, convective physics and environment
• triggering and adjustment processes eyewall
  replacement cycles, eyewall mixing

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Science Issues cont

• AIR SEA INTERACTION OCEANIC/ATMOSPHERE BOUNDARY
  LAYER)
• Air sea fluxes under disturbed conditions (sea
  spray)
• Turbulence and subgrid scale mixing
• Coupled atm/ocean model coupled wind-wave model
• UPPER OCEAN PROCESSES
• SST changes depth of warm layer (accounts for
  turbulent mixing, horizontal advection)
  e.g. Gulf Stream and loop currents, warm core
  eddies, cold wakes
• LAND SURFACE PROCESSES
• PBL fluxes storm structure -- coupling to
  hydrologic processes

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To advance TRACK forecasts AND improve INTENSITY,
STRUCTURE and RAIN Forecasts

• Need high quality hurricane core and
  environmental observations
• Need advanced data assimilation techniques for
  environment and hurricane core
• Need advanced modeling system
• Need a disciplined approach for transition from
  research to operations, e.g. JHT, JCSDA

critical observations for intensity/structure
and rain problem
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Advanced Observation Platforms for Hurricanes

• Environment (Winds, Moisture, Temp.)
• In-situ G-IV, UAVs, Driftsondes
• Satellite ADVANCED MICROWAVE INSTRUMENTS
• Hurricane Core (Winds from 12 km to surface)
• G-IV, WP-3D airborne Doppler radars
• 88-D Level II data
• Upper Ocean (SSTs, wave height, mixed layer
  info)
• AXBTs, Altimeter, ARGOS, Current Meter, Buoys

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Required Data Assimilation Development

• Advanced Data Assimilation Techniques
• Environmental flow in progress (some success)
• Hurricane Interior - substantial RD
  necessary
• Ocean data assimilation new effort (GODAS)
• EMC is developing scale-dependent covariances

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• Hurricane WRF (HWRF) Prediction System
• Community based next generation hurricane
  prediction system
• Will replace the GFDL in 2007
• Coupled air-sea-land prediction system
• Advanced data assimilation for hurricane vortex
• Advanced physics for high resolution
• Land surface coupled to hydrology/inundation
• Nested wave prediction
• Coupling to dynamic storm surge (in planning)

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TRANSITIONING TO HURRICANE WRF
02 03 04 05 06 07
Mesoscale Data Assimilation for Hurricane Core
GFDL frozen HWRF TE
Continue upgrades
GFDL
Begin Physics Upgrades
HWRF Operational
Transition to HWRF
MM5

HWRF TE
Preliminary Test HWRF
physics
HWRF
Begin RD
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• Pre-Implementation Strategy for HWRF
• INCREASE RESOLUTION
• UPGRADE GFDL PHYSICS WITH GFS PHYSICS
• IMPLEMENT MICROPHYSICS, SFC. PHYSICS
• PUT PHYSICS IN WRF FRAMEWORK
• MIGRATE ALL PHYSICS TO NMM, e.g. HWRF
• CARRY OUT TEST EVALUATION ON UPGRADED GFDL
  SYSTEM (GFDL FROZEN 05-06)
• PERFORM EXTENSIVE COMPARISONS BETWEEN GFDL AND
  HWRF FOR MULTIPLE SEASONS AND STORMS

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• DEVELOPMENT OF THE HWRF SYSTEM
• Movable, nested grid (configuration, domain)
• Advancement of physics (wheel of pain)
• Initialization (development of DA for hurricane
  vortex) (LONG TERM EFFORT)
• Coupling to HYCOM
• Coupling to WAVEWATCH III ( multi-scale model)
• Coupling to LSM
• Development/Upgrade of hurricane verification
  system (PPT, STRUCTURE)
• Coupling to storm surge-wave coupled model
  (planning stage)
• HWRF ensembles

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THE PHYSICS WHEEL OF PAIN
Compliments of Dr. Jaiyu Zhou (NOAA/OST)
Direct Physical Interaction of Clouds

• - Hydrometeor type (phase)
• - Cloud optical properties
• - Cloud overlap (merging Cu, grid-scale
  cloudiness)
• - Cloud fractions
• - Precipitation
• - Sfc energy fluxes
• 4. - Convection, PBL evolution, precipitation

Radiation
Cu Scheme
Sfc PBL
Grid Scale Microphysics
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Hurricane-Wave-Ocean-Surge-Inundation Coupled
Models
NOS land and coastal waters
NCEP Atmosphere and Ocean
HWRF
NOAH LSM
runoff
High resolution Coastal, Bay Estuarine
hydrodynamic model
surge inundation
fluxes
Atmosphere/oceanic Boundary Layer
radiative fluxes
winds air temp.
other fluxes
elevations currents 3D salinities
temperatures
SST currents
HYCOM 3D ocean circulation model
wave spectra
WAVEWATCH III Spectral wave model
wave fluxes
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HYCOM Expt Hurricane Isabel

• MODEL
• HYCOM Mercator North Atlantic 1/12 degrees (?x
  7 km).
• 26 vertical coordinates.
• Vertical viscosity and mixing GISS.
• FORCING 6-h NCEP (GFS analysis).
• INITIAL CONDITIONS from near-real time North
  Atlantic system (NRL RSMAS) (O.M. Smedstad).
• PERIOD Sept. 3-30, 2003

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SSH and cross section positioning
?H30 cm
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Temperature cross sections for Sept 11, 15-21, 30
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GFDL Coupled Model
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C-BLAST BUOYS DURING FRANCES
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Hurricane Frances impact of coupling
Blue- GFDL operational coupled model Red- GFDL
uncoupled model
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The Future
Deep ocean model resolution dictated by GFS model
Higher coastal model resolution dictated by model
economy
Highest model resolution in areas of special
interest
Hurricane nests moving with storm(s) like GFDL
and HWRF
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Technology Infusion
Joint Hurricane Testbed Mission Statement The
mission of the JHT is to transfer more rapidly
and smoothly new technology, research results,
observational and model advances into improved
tropical cyclone analyses and prediction at
operational hurricane forecast centers.