NOAA Intensity Forecasting Experiment (IFEX)

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NOAA Intensity Forecasting Experiment (IFEX)
PDF available at AOML anonymous FTP
ftp.aoml.noaa.gov /pub/hrd/rogers/HFP/IFEX_framew
ork.pdf
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Motivation

• Significant improvement in track forecasts over
  past 30 years
• Much less improvement in intensity forecasts
  Why?
• gaps in our understanding of the physics of
  tropical cyclones and their interaction with the
  environment.
• deficiencies in routinely collecting data and
  assimilating it into the modeling system
• limitations in the numerical models themselves
• Accurate forecasts will rely heavily on the use
  of improved numerical modeling systems, which in
  turn will rely on accurate observational datasets
  for assimilation and validation.

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Overview of IFEX (15 July 30 Sept)

• HRDs efforts will work toward improving
  forecasts of tropical cyclone intensity and
  rainfall by providing data to improve the
  operational numerical modeling system (i.e.,
  HWRF) and by improving our understanding of the
  physics of intensity change and rainfall
• IFEX will focus on providing measurements of
  tropical cyclones at all stages of the tropical
  cyclone's life cycle, from pre-genesis to
  intensification and subsequent landfall or decay
  over water
• Will provide invaluable information from sparsely
  observed environments
• The ability to target multiple basins provides
  greater flexibility for observing tropical
  cyclones at different stages of their life cycle

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Proportion of HRD research flights stratified by
lifecycle stage in the P-3 era (1976-2004)
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Requirements and Recommendations

• Requirements High Priority
• Collect observations throughout the life cycle of
  a tropical cyclone for the development of 3-D
  variational assimilation of the hurricane core
  circulation.
• Collect observations of the atmosphere and ocean
  in and around the storm scale circulation that
  can be used to develop an evaluation and
  validation package for the high resolution HWRF.

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Requirements and Recommendations (cont.)

• Requirements High Priority
• Collect observations in a variety of
  atmospheric/oceanic conditions (e.g. atmospheric
  shear, warm core eddies) to assess the influence
  of these features on observed and model TC
  intensity and structure changes.
• Improve understanding and develop improved model
  representations of sea spray/surface flux effects
  on boundary layer structure and microphysics,
  especially in the core and rainbands. Develop
  techniques for evaluating ocean vertical mixing
  parameterizations against observed data.

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Requirements and Recommendations (cont.)

• Recommendations Medium Priority
• Improve the understanding of the phase changes of
  moisture.
• Determine the storm intensity and structure
  change during decay over cold water.

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Flight modules

• Tropical Cyclogenesis Module
• Investigate role of low- and mid-level vortex
  interactions in genesis (2 P-3s, 1 G-IV)
• Mature Storm Module
• Collect observations from the sub-surface to the
  upper atmosphere for a mature TC, from the inner
  core to the synoptic environment (2 P-3s, 1
  G-IV)
• Tropical Cyclone Wind Fields near Landfall Module
• Mapping of the TC kinematic and thermodynamic
  changes during landfall (2 P-3s)
• Saharan Air Layer Module
• Study the mechanisms by which the SALs embedded
  mineral dust, thermodynamic properties, and
  low-level wind surge affect Atlantic TC genesis
  and intensity change (1 G-IV)

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Partnering Experiments for 2005

• NASA TCSP (multiple P.I.s TBD)
• mid-June early August 2005
• NASA aircraft based in San Jose, Costa Rica
• Science team TBD by 1 January
• NSF RAINEX (Houze, Chen, Lee)
• August-September 2005
• Ground operations based in Miami, flights in
  Atlantic
• Proposal has been accepted
• Planning meeting 15-17 November in Miami (at
  RSMAS)
• NOAA Ocean Winds (Chang)
• Same as previous years

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Tropical Cyclone Life Cycle and Experiment
Coverage
IFEX (NOAA)
TCSP (NASA)
RAINEX (NSF)
Ocean Winds (NOAA)
time
tropical depression
tropical wave
tropical storm
hurricane
genesis
organization
mature
landfall/ decay