The Houston Environmental Aerosol Thunderstorm (HEAT) Project: 2005

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The Houston Environmental Aerosol Thunderstorm
(HEAT) Project 2005
http//www.met.tamu.edu/ciams/heat/index.html
Richard (Dick) Orville with John Nielsen-Gammon,
Renyi Zhang, Don Collins and Amy Stuart Dept. of
Atmospheric Sciences Texas AM
University College Station, TX Email
rorville_at_tamu.edu March 15, 2004
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Introduction Houston, the Lightning Capital of
Texas

• National Lightning Detection Network (NLDN)
  analyzed climatological data (Orville et al.
  2001) have indicated a significant CG lightning
  enhancement (60) over and near the city of
  Houston, Texas (pop. 5 million).
• The hypothesized causes include
• The urban heat island effect enhancing convection
• The petroleum refining operations (49 of the USA
  capacity)
• The sea breeze circulation system and increased
  CCN/IN concentrations from the multitude of
  pollution sources in the Houston region.

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Intracloud Lightning
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• Cloud-to-ground lightning

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Data and Methods

• The National Lightning Detection Network (NLDN)
• Detects only CG flashes
• 106 sensors (DF/TOA) across the U. S.
• Since 1994, the resolution is 500 m, and
  detection efficiency is 85
• Created and analyzed lightning flash density maps
  for different season and time periods

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E60
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Sea Heat Island Breeze

• From MM5 simulations Orville et al., 2001,
  enhanced low-level convergence does not occur
  without the city.
• The main effect is increased thunderstorm
  initiation directly over the city.
• Greater warm season daytime enhancement gives
  support for this.

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Pollution

• Houston atmosphere is polluted due to the oil
  refineries and automobiles
• Hypothesis Effect of CCN concentrations on
  lightning
• Higher CCN
• Mean drop radius decreased
• More small supercooled droplets above 0o C level
• Greater volume of mixed phase (ice and
  supercooled water)
• More charge separation
• More lightning!

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Proposed Research

• Houston has a significant lightning enhancement
  during all seasons, but highest in the summer.
• Field experiments (CCN/IN, cloud droplet size
  distributions over Houston), and modeling
  (separate effects from city, bay, and pollution)
  should help in determining the relative
  importance of each factor.
• HEAT Project is needed with measurements of total
  lightning (both cloud-to-ground and intracloud
  lightning), polarimetric radars, and aircraft
  sampling of clouds.

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Houston Environmental Aerosol Thunderstorm (HEAT)
Project 2005

• Houston Environmental AerosolThunderstorm
  Project(HEAT)
•                     DRAFT                   
  
• Scientific Overview Operational Plan for
  HEAT-2004/2005
• Table of Contents     Download PDF
• Abstract 1. Introduction    1.1 Primary Goals
  of HEAT          Pollution Effects         
  Urban Heat Island Dynamics          The Effect
  of a Complex Coastline          Atmospheric
  Chemistry           Lightning 2. Project
  Overview 3. Scientific Objectives    3.1
  Pollution Effects    3.2 Urban Heat Island
  Dynamics    3.3 The Effect of a Complex
  Coastline    3.4 Atmospheric Chemistry    3.5
  Lightning 4. Operation Plan Daily Schedule and
  Conduct of Operations    4.1 Briefings    4.2
  Conduct of Field Operations and the Operations
  Center          4.2.1 Operations Center
  Team          4.2.2 Chief Coordinators and
  Representatives for the                   Major
  Components and Observing Systems    4.3
  Operations Center Layout  

• http//www.met.tamu.edu/ciams/heat/index.html

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Primary Goals of the HEAT Project

• Evaluate the pollution effects (small aerosols)
  and precipitation suppression
• Evaluate the urban heat island (UHI) dynamics
  (e.g. Huff and Changnon 1972)
• Evaluate the effect of a complex coastline
• Low level convergence
• Interaction of sea breeze with UHI
• Effect of sea breeze on convection intensity

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• Atmospheric Chemistry
• Thunderstorms are efficient in transporting
  planetary boundary air to higher levels. Flux of
  certain atmospheric constituents (CO, CO2, O3,
  HC, NOx and aerosols) will be measured by
  aircraft observations into and out of storms.
• Lightning Total lightning (IC and CG) will be
  measured. Why a 58 enhancement (CG) over urban
  area?

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Scientific objectives

• Lightning
• Measure the total lightning over Houston
• Determine the lightning polarity over Houston
• Obtain thunderstorm electric field profiles over
  Houston and over non-urban environments.

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(cont)

• Cloud microphysics
• Objective M1 Mixed-phase region
• Objective M2 Cloud droplet spectra
• Objective M3 Precipitation drop-size
  distributions
• Objective M4 Pollution effects in the
  early-storm stages

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(cont)

• Urban heat island dynamics
• Objective U1 Urban heat island thermodynamics
• Objective U2 Urban wind modification
• Objective U3 Urban updraft enhancement
• Objective U4 Urban effects on convective storm
  mergers and lightning production

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(cont)

• The effect of a complex coastline
• Objective C1 Sea breeze modification low level
  convergence field associated with a complex
  coastline and its effects on convective
  initiation
• Objective C2 Sea breeze interaction with the
  Houston heat island
• Objective C3 Intensity of sea breeze convection

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(cont)

• Atmospheric chemistry
• Objective A1 NOx production by lightning
• Objective A2 Transport and fate of pollutants in
  thunderstorms
• Objective A3 Effect of urban thunderstorms on
  upper tropospheric chemistry

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Project Overview Approximate locations of
CSU-CHILL polarimetric radar, S-Pol polarimetric
radar, NWS WSR-88D radar, upper air sites, TAOS
sites, and wind profiler sites. The Houston
metro area is outlined in red.
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Total (CG plus IC) Lightning and Polarimetric
Radar Measurements
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Note that the sensor spacing is closer in the
middle of the network and farther apart on the
outside of Houston. Green stars airports with
the exception of the green star in the center of
Houston.
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Radar Systems

• NCAR S-Pol radar
• CSU-CHILL Research radar
• NWS WSR-88D Operational weather radar
• Texas AM, NSSL, OU, Texas Tech mobile C- band
  radars (2)

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Aircraft Systems

• University of Wyoming King Air
• WMI Lear Jet
• North Dakota Citation
• Airborne chemistry instrumentation (Baylor)
• HIAPER

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Balloon Sounding Units

• MGLASS Units (2)
• Mobile electrical sounding units (2)
• TAOS units
• Upper air sounding station

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Lightning Detection

• National Lightning Detection Network (NLDN) for
  CG lightning (in place since 1989)
• Lightning Detection and Ranging (LDAR II) network
  (Funded September 2003 NSF) to detect total
  lightning (IC and CG)

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Conclusions

• Field observing systems in HEAT (2005) will
  include
• Radar systems
• Surface mesonet systems
• Aircraft
• Balloon sounding units
• Lightning detection and mapping arrays
• All lightning discharges are detected
• Cloud-to-ground
• Intracloud
• Up to several thousand locations for an
  individual flash
• Location accuracy of 50 to 100 meters
• Charge layers can be identified
• Flash type can be identified

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The Beginning!
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Time of Arrival Lightning Mapping System (LDAR
II)
Radiation occurs at time t, at location (x, y, z)

• Measure time RF pulse arrives at multiple
  stations
• Determine position and time of source
• Locate hundreds to thousands of sources per flash

Radiation arrives at station i at time ti,
location (xi, yi, zi)
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Layout of LDAR II Plots
Altitude vs. Time (Color Coded)
Number of LDAR II Points vs. Height
Altitude vs. x
Plan View (x vs. y)
Altitude vs. y
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LDAR II Image of an airplane avoiding thunderstorm
s 20 Minutes of Data Plane Flying 400 MPH
at 30,000 ft
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Intra-Cloud Lightning
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Cloud-to-Ground Lightning
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LDAR-II Antenna FAA Facility in Texas Ground
Mount
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LDAR-II Antenna -Roof of DFWAirport
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Note that the sensor spacing is closer in the
middle of the network and farther apart on the
outside of Houston. Green stars airports with
the exception of the green star in the center of
Houston.
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3D/2D Lightning Mapping - LDAR II

• Most advanced lightning detection capability in
  the world
• In 1997, GAI and NASA entered into a technology
  transfer agreement (NASA had been using VHF
  lightning detection for many years)
• In 1999, GAI and NMT began a collaboration that
  lead to the future commercialization of LDAR II
  (NMT had developed a similar VHF lightning
  detection sensor with slightly different
  technology)
• 3-Dimensional mapping within network perimeter
• 100-200 meter or better location accuracy
• Greater than 95 expected flash detection
  efficiency
• Reduces to 2-dimensional mapping well outside of
  the network (150 km)
• 2 km or better location accuracy
• Greater than 90 expected flash detection
  efficiency

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Conclusions

• Field observing systems in HEAT (2005) will
  include
• Radar systems
• Surface mesonet systems
• Aircraft
• Balloon sounding units
• Lightning detection and mapping arrays
• All lightning discharges are detected
• Cloud-to-ground
• Intracloud
• Up to several thousand locations for an
  individual flash
• Location accuracy of 50 to 100 meters
• Charge layers can be identified
• Flash type can be identified

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The Beginning!
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• Lightning sensor for cloud-to-ground lightning
• Installation for experimental use at Texas AM

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Option I No Storm/Before Storm Initiation/Before
Storm Enters Domain (including Sea Breeze)

• Goals Document ambient pollution levels,
  vertical atmospheric thermodynamic structure and
  E-fields
• Instruments King air, T-28, MGLASS, mobile
  electrical sounding units

Harris County
Sea Breeze Front
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Option IIIsolated Urban Storm

• Goals Document storm cloud droplet spectra, ice
  nuclei content, and amount of supercooled water
  E-field measurements inside/outside of storm
• Instruments T-28, mobile electrical sounding
  units

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Option IIIIsolated Environmental and Urban
Storms in Coexistence

• Goals Document cloud droplet spectra, ice nuclei
  content, amount of supercooled water, and
  E-fields in/near convective cores for an urban
  and one environmental storm.
• Instruments T-28, mobile electrical sounding
  units

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Option IVStorm System Transgressing Study Area
(i.e., squall line)

• Goals Document cloud droplet spectra, ice nuclei
  content, amount of supercooled water, and
  E-fields in/near convective cores for urban and
  environmental portions of the system. Sample
  before, during, and after propagating through
  Houston.
• Instruments T-28, mobile electrical sounding
  units

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Title The Houston Environmental Aerosol
Thunderstorm (HEAT) Project Principal
Investigators Richard Orville, John
Nielsen-Gammon, Renyi Zhang, and Don Collins
(Texas AM University) Proposed Co-investigators
Danny Rosenfeld (Hebrew University), William
Woodley (Woodley, Inc.), Earle Williams (MIT),
John Helsdon and Andy Detwiler (South Dakota
Tech), Steve Rutledge (Colorado State), Paul
Krehbiel (New Mexico Tech), Maribeth Stolzenburg
and Tom Marshall (U. of Mississippi), Walt Lyons
(FMA, Inc.), Ron Holle, Ken Cummins, and Nick
Demetriades (Global Atmospherics, Inc.), David
Rust and Don MacGorman (National Severe Storms
Laboratory), Bill Read and Steve Allen (National
Weather Service, Houston), Daewon Byun
(University of Houston), J. G. Hudson (Desert
Research Institute, Nevada), J. Marshall Shepherd
(NASA-Goddard), Gary Huffines (U.S. Air Force),
NCAR-MMM personnel to be determined, Lead
Institutions Texas AM University and the
National Center for Atmospheric Research
(NCAR) Project Period Four years (2003-2007)
field program (summer 2005)