CAMEX-3

The CAMEX-3 field campaign was devoted to the study of hurricane tracking and intensification using NASA-funded aircraft with remote sensing instrumentation. The NASA ER-2 and DC-8 were utilized along with the University of North Dakota’s Cessna Citation II Research Aircraft.

The remote sensing instrumentation used by NASA during CAMEX-3 yielded high-resolution spatial and temporal information on hurricane structure, dynamics, and motion. These data, analyzed within the context of more traditional aircraft, satellite, and ground-based radar observations, provided additional insight to hurricane modelers and forecasters who continually strive to improve hurricane predictions. The ultimate goal of CAMEX-3 was to provide information which could someday assist in decreasing the size of coastal evacuation areas and increasing the warning time for those areas.

Study Dates	August - September, 1998
Region	Atlantic coast
Phenomena Studied	Hurricane tracking and intensification

ER-2 Instruments - Characteristics

Instrument Acronym	Instrument Type	Temporal Resolution	Spatial Resolution	Data Vol/Mission
AMPR	Scanning radiometer (10, 19, 37, 85 GHz)	One 50-element scan every 3 seconds	0.6 km at 85 GHz; 1.5 km at 37 GHz; 2.8 km at 10 19 GHz, (surface footprint)	20-30 MB
EDOP	Doppler Radar	2 Hz rate. (~100m along-track)	Vertical: 37.5 m; Horizontal: ~1.1 km at surface and ~0.55 km at 10 km	~3.5 GB
LIP	Electric Field Mills, Conductivity probe	10 Hz, continuous	~20m	30-50 MB
MAMS	Scanning visible/IR sensor	Continuous	100 m, at nadir (surface)	~1 GB
MAS	Scanning spectrometer	Continuous	50 m, at nadir	5-10 GB
MIR	Scanning radiometer (89, 150, 183, 220, 325 GHz)	One scan cycle every 3 seconds	~1-2 km at surface	20-25 MB
NAST-I	Scanning interferometer	Continuous	2.5 km at nadir	5-10 GB
NAST-MTS	Passive microwave radiometers	continuous scan, 6 sec period, 120 msec nominal integration time for raw data	2.6 km from 20-km altitude at nadir	< 100 MB

ER-2 Instruments - Science Objectives

Instrument Acronym	General Hurricane	Landfalling Hurricane	TRMM Science Cal/Val	Alternate Science
AMPR	Convection/storm intensity, relationships, eye wall structures, rain mapping	Rain mapping, changes of convection in landfalling storms; relationship of electrification to signal storm intensity changes	Validation of TMI TB and rain algorithms	Underflights of SSM/I and TMI
EDOP	Storm dynamics, eye wall structures, storm microphysics	See AMPR description	Vertical storm structure, validation of algorithms and PR vertical structure	-
LIP	Convection/Storm intensity relationships, eye wall structure, rain mapping, relationships of lightning/electrification to storm dynamics/microphysics	See AMPR description	CAL/VAL: validation of LIS and rain algorithms	Validation of Optical Transient Detector (OTD)
MAMS	Upper tropospheric humidity, water vapor and SST	-	Validations of VIRS	Validation of MODIS 6 micron channel
MAS	Cloud microphysics at high resolution	-	-	Cal/Val of MODIS on cross calibrations with NAST
MIR	Water vapor profiles, ice water path	See AMPR description	-	NOAA-K and DMSP underflights
NAST-I	Thermodynamic structure, eye subsidence/warm core, surface heat flux relationships	Thermal gradient, wind steering	Precipitation height from microwave validation	NOAA-K validation, AIRS spectroscopy and algorithm validation
NAST-MTS

ER-2 Instruments - Products

Instrument Acronym	Direct Products	PI-Derived Products	Potential Products
AMPR	Raster TB imagery; In-field: Calibrated TB	Lat/Lon gridded TB imagery	Precipitation rate, hydrometeor profiles
EDOP	Reflectivity, doppler velocity; In-field: Uncalibrated reflectivities & velocity for selected flights	Attenuation corrected reflectivity, hydrometeor vertical motions	Vertical velocities, horizontal flow, rainrate, path attention, surface backscatter cross section, air flow streamlines
LIP	Atmospheric conductivity, eletric field components, and aircraft charge In-field: Quick looks at direct products	Total lightning count and rates; lightning statistics; storm current output, storm charge structure	Quantified lightning related with precipitation, convective mass/ice flux, latent heat, storm current output
MAMS	Calibrated brightness temperature (IR) and radiance (Vis); In-field: Vis/IR images and line plots of nadir brightness temperatures	Total column water vapor; sea/land surface temperature	Cloud top height and temperature
MAS	Calibrated brightness temperatures (IR bands) and radiances, sub-sampled imagery; In-field: MAS quick look	Cloud particle phase, cloud height, cloud mask	Aerosol optical depth, cloud reflectance, precipitable water
MIR	Calibrated brightness temperatures, raster brightness images; In-field: water vapor profiles if temperature profiles available and brightness temperature images	Water vapor profiles (require temperature profiles)	-
NAST-I	Calibrated brightness temperature spectra IR	Atmospheric soundings, ocean surface temperatures, precipitation cell height, cloud height/radiative properties, cloud microphysical properties	Cloud properties
NAST-MTS	microwave brightness temperatures	Interpolated, microwave-only, clear-air temperature retrievals	Microwave-Infrared combined temperature and humidity and retrievals with cloud corrections.

ER-2 Instruments - Planning Needs

Instrument Acronym	Critical Science Data	Mission Planning Data Needs	In-field Products
AMPR	LIP, sondes, VIS/IR, passive microwave, radar, rain gage, microphysical	GOES, SSM/I, WWW access.	Calibrated TB images
EDOP	LIP, sondes, VIS/IR, passive microwave, radar, rain gage, microphysical	GOES, WSR-88D, NIDS, Web access	Uncalibrated reflectivities and velocity data for select periods of flight
LIP	Passive microwave, TRMM obs, NLDN/KFC lighting, radar	WSR-88D, GOES, NLDN, LDAR, RDI, TRMM, OTD, SSMI, satellite orbit predictions	Electric fields (and perhaps lightning)
MAMS	EHAD, LASE, MIR, GOES	-	VIS/IR images, Line plots of nadir TB
MAS	NAST-I, NAST-MTS, in situ microphysical MODIS	EOS-AM1 overpass information	MAS quick-look
MIR	EHAD, RAOB, MTS, NAST-MTS, HIS, lidar, radar	-	TB images, (Water vapor profiles if temp. profiles avail.)
NAST-I	MIR, MAS/MAMS, dropsondes, GOES, NOAA-K	GOES	SST
NAST-MTS	NAST-I, radiometers (MIR, AMPR), radiosondes	TBD	Raw data imagery, video images

ER-2 Instruments - Aircraft Maneuvers

Instrument Acronym	Preferred Maneuvers	Dropsondes	Unfavorable Maneuvers	Unfavorable WX Conditions
AMPR	Clear ocean level flight track for 5 minutes > 20 km altitude at start and end of mission	Two/flight. One at each preferred manuever	Non-level flight track. Require pitch/roll angle < 2 deg. with minimal variations	-
EDOP	Roll manuever of -5 to +5 degs. over ocean; 360 deg. turn at 7-10 deg. bank angle over clean ocean	Five per flight; some in or near eye wall; inner core and outflow regions	Non-level flight track. Require minimal pitch/roll/yaw	-
LIP	Level flight at 5, 10, 15 km for 10 minutes each once during the experiment	-	-	-
MAMS	-	2-3 per flight, 1 per hour, primarily clear sky	Roll angle > 15 degrees	Clouds
MAS	Straight and level flight	1-2 per flight in clear and transmissive cloud conditions	Roll angle > 3 deg.; pitch angle > 2 deg.	Intense sunlight
MIR	-	2-4 per flight over clear targets	-	-
NAST-I	Level flight, tracks over downwind environment, tracks across eye, flight over Andros Island	1-5 per flight	Roll ange > 3 deg., pitch angle > 2 deg.	-
NAST-MTS	-		-	-

DC-8 Instruments - Characteristics

Instrument Acronym	Instrument Type	Temporal Resolution	Spatial Resolution	Data Vol/Mission
AMMR	Radiometer (fixed) 10-92 GHz 45 deg upview: 21 and 37 GHz Nadir view: 18 and 37 GHz	1 second	~1-2 km @ surface
ARMAR	Doppler radar (13.8 GHz) (Thru-nadir scanning) (multi-polarization)	1.8 seconds/scan 10 MHz sample rate 5 kHz PRF	800 m at surface, 80 m range resolution (after averaging)	> 10 GB (raw), 200-600 MB (processed)
AVAPS	NCAR/GPS sonde	System can track 4 sondes simultaneously	10 m (vertical)	<50 KB per sonde release
CAPAC	FSSP300 aerosol/cloud partice spectrometer; 2D-Cloudprobe; 2D-Precipitation probe; 2D-Greyscale probe; Cloudscope	.1 Hz	2 km (at 200 m/sec aircraft speed)	< 1 GB
JPL SAW	Microhygrometer	TBD (up to 0.1 sec)	Single point measurement	10 MB
Laser Hygrometer	diode laser spectrometer	nominally 1 sec @ 10Hz, minimum .128 sec @ 8Hz.	Dependent on sampling rate. 25 meters minimum.	500 KB
LASE	Differential Absorption Lidar	3 seconds per profile; 2 min. (averaged)	Water profiles: 0.2 km (vert.), 5 km (horiz.), 100 m to tropopause Relative aerosol scattering profiles: 30 m (vert.), 200 m (horiz.), ground to 20 km	200 MB
MACAWS	Doppler lidar (side-scanning)	Depends on pulse repetition frequency, scanning pattern, signal processing parameters	Horizontal coverage 2-30 km; Horizontal resolution: Line of Sight winds 150-450m, Calculated wind vectors 1-3 km; Vertical coverage 4.2-10 km	500 MB
MMS	Rosemount probes	up to 5-Hz	40-m at 200 m/s airspeed	preliminary field data: 2-Mbyte high resolution data: 25-Mbyte
PSR	Passive microwave radiometer	Complete conical scan each 10 seconds, independent radiometric samples every 25 msec.	2.5x5 km footprints at 10.7 & 18.7 Ghz, 12 km altitude; 0.8x1.3 km footprints at 37& 89 Ghz, 12 km altitude;	30 Mbytes [raw data]

DC-8 Instruments - Science Objectives

Instrument Acronym	General Hurricane	Landfalling Hurricane	TRMM Science Cal/Val	Alternate Science
AMMR
ARMAR	Vertical velocity studies; Eyewall structure		Precipitation radar validation studies (clear air and rain); Rain type classification; Beamfilling studies
AVAPS	Incremental observational resolution of hurricane dynamic and thermodynamic structure	Impact of adaptive observations on intensification and tracking forecasts	Input to radiative transfer models	CAMEX-3 sensor validations
CAPAC	Cloud particle size distributions and condensate mass		Condensate mass to compare w/ remotely sensed values
JPL SAW
Laser Hygrometer
LASE	Characterize hurricane environment using water vapor, aerosol, & cloud measurements; Input to models & assimilation schemes; Fill in sonde data voids
LIP	Convection/Storm intensity relationships, eye wall structure, rain mapping, relationships of lightning/electrification to storm dynamics/microphysics	Rain mapping; changes of convection in; landfalling storms; relationship of electrification to; signal storm intensity changes	CAL/VAL: Validation of LIS and rain algorithms	Validation of Optical Transient Detector (OTD)
MACAWS	Eyewall dynamics, role of low-level inflow in rapid intensification	Impact of lidar adaptive observation on intensification & tracking forecasts	Relationship between wind environment and deep convection	Near-sea surface wind comparison w/ scatterometers; Satellite Doppler wind lidar performance simulations (incl. SPARCLE); Aerosol backscatter validation w/ MSFC Continuous Wave lidar; Angular dependence of sea surface scattering
MMS
PSR	Image precipitation bands and surface winds around eyewall; improve algorithms for wind, cloud, and rain retrieval; study high-resolution polarimetric signature structure within rain bands.	Improve passive microwave precipitation retrieval algorithms for near-shore areas;	Compare colocated TRMM/PSR polarimetric signals for consistency; study beam-filling effects using high-resolution passive microwave imagery; compare retrieved PSR products to peak TRMM products to determine level of bias in extreme parameter regions. Compare PSR raw observations and retrieved products with those of TMI and SSM/I.	Obtain first high-resolution multiband polarimetric conically-scanned imagery over strong convection and winds.

DC-8 Instruments - Products

Instrument Acronym	Direct Products	P.I. Derived Products	Potential Products
AMMR	Calibrated TB (18-37 GHz)	Water vapor profiles (requires temperature profiles)
ARMAR	In-field: Equiv. reflectivity factor Ze, Doppler velocity, Cross-polarization reflectivity, HH-VV correlation coefficient, HH-VV phase difference	Rain rate, Updraft velocity, Latent heating	Rain rate, Updraft velocity, Latent heating
AVAPS	Profiles of temperature, pressure, humidity, and wind velocity
CAPAC	In situ particle density, size, and shape (few um to 1.6 mm for 1st and 4th instrument; 0.2 um to 20 um for 2nd and 3rd instrument). In-field: above for a few periods	Cloud/aerosol part. size distrib. (0.2 um<D<1.6mm, Diameter); Condensed water volume
JPL SAW	In situ dewpoint/frostpoint, pressure, temperature (raw data). In-field: plots of dewpoint/frostpoint	In situ dewpoint/frostpoint, pressure, temperature (formatted data)
Laser Hygrometer	In-situ water vapor volume mixing ratio along the DC-8 flight track		intercomparisons with the other water vapor sensors on the DC-8; water vapor data will be utilized by the lidar teams and the modelling teams to define atmospheric conditions and analyze atmospheric dynamics
LASE	Profiles of water vapor mixing ratio and aerosol scattering. In-field: Color images of water vapor mixing ratio & relative aerosol scatttering cross sections	Cross sections of water vapor mixing ratios, relative humidities, total atmosphere scattering ratios, and aerosol backscattering coefficients	Total precipitation water; Aerosol extinct. profiles; Aerosol optical thickness; Cloud base/top height; Relative humidity profiles; Boundary layer height
LIP	Electric field components, aircraft charge. In-field: Quick looks at direct products	Total lightning count & rates, lightning statistics, storm current output, storm charge structure (last two in conjunction with ER-2 measurements)	Quantified Lightning; relationship with precipitation; convective mass/ice; flux, latent heat; storm current output
MACAWS	LOS wind velocities and relative backscatter as a function of location, range from aircraft, elevation angle, & azimuth angle. In-field: LOS velocity and relative backscatter with respect to time/height	Selected 2-D wind fields as a function of elevation angle with respect to aircraft	2D wind fields, kinematic quantities, fluxes, Richardson number
MMS	1-Hz data: time, pressure, temperature, theta horizontal wind (U,V), vertical wind (W), turbulence index 5-sec data: latitude, longitude, pressure-altitude, true-air-speed
PSR	Polarimetric, multiband, fore/aft conically scanned, and geolocated brightness temperature maps	Surface wind speed and wind direction, integrated cloud water content, near surface rain rate.	Improved P.I. derived products using rain radar data and integrated water vapor data.

DC-8 Instruments - Planning Needs

Instrument Acronym	Critical Science Data	Mission Planning Data Needs	In-field Products
AMMR
ARMAR	Radiometer, Other aircraft radars, Ground-based radars, Aircraft microphysics	Satellite VIS/IR, Ground-based radar	Reflectivity images
AVAPS	GPS constellation telemetry
CAPAC	MMS and DADS data		Time series of particle number, volume, and surface area, Size distribution @ particle shapes for a few selected time periods
JPL SAW			Time series plots of dewpoint/frostpoint
Laser Hygrometer	Pressure and Temperature from MMS (or equivalent) Comparisons with other H2O sensors are valuable	Pressure and Temperature	water vapor volume mixing ratio. Preliminary data within 1-23 hours of flight termination provided pressure and temperature data are available from MMS
LASE	Dropsonde winds & temperature; Scanning HIS temperature crosssections	GOES Imagery; Radar precipitation imagery; General meteorological observations; Hurricane forecasts	Color images of water vapor mixing ratio & relative aerosol scattering cross sections
LIP		WSR-88D, GOES; NLDN, LDAR, RDI; TRMM,OTD,SSM/I; satellite orbit; predictions	Electric fields and conductivity (perhaps lightning statistics)
MACAWS	MSFC Continuous Wave lidar	Hurricane intensity & tracking forecasts; VIS/IR/WV satellite images; Hurricane recon. observations	Line of Sight velocity time/height cross-section images, Selected 2-D wind field images Time/height cross-section images of relative backscatter
MMS
PSR	Particle size measurements, ARMAR radar data. SSM/I data, RADARSAT data; GOES IR imagery	Weather FAX on board DC-8 to provide near real-time picture of conditions.	Maps of wind speed and direction, surface rain rate, and cloud liquid water.

DC-8 Instruments - Aircraft Maneuvers

Instrument Acronym	Preferred Maneuvers	Dropsondes	Unfavorable Maneuvers	Unfavorable WX Conditions
ARMAR	Level flight lines; Some banking desired	One near data collection area (no rain/light rain)
AVAPS			Sharp turns	Heavy rain, large hydrometeors
CAPAC			Steep (>1000 feet per minute) descents and ascents
JPL SAW			Rapid descent from cold, dry conditions to warm, humid conditions	Rain
Laser Hygrometer			Sharp turns may affect optical alignment.	Rain on ground
LASE	Moderate to high altitude (> 25 kft)		Attitudes where zenith port axis is < 15 deg. relative to sun	Clouds (data collected between aircraft & clouds)
LIP	Straight, level flight paths; 1-2 Banking maneuvers required per experiment for calibration
MACAWS	Straight lines at constant altitudes of 1000 - 41000 ft; Spiral ascents/descents in optically-clear eye; Orbits of 5-30 km diameter over a ground point	1-2 per mission in relatively clear area	Frequent changes in heading or altitude; Exceeding ground speed of 450 kt; Drift angle < 10 degrees	Optically-dense clouds, precipitation, extremely clean air
MMS	Five sinusoidal pitching cycles, five sinusoidal yawing cycles, and square box pattern spanning 0-360 deg of heading. Once per flight in "calm" air at a specific MACH number for instrument calibration			cold wet cloud encounters
PSR	Straight and level flight at altitudes between 30,000' and 45,000' from at least two different non-orthogonal flight directions Brief 60o left rolls	3-5 per mission	None	None

Ground-Based Instruments - Characteristics

Instrument Acronym	Instrument Type	Temporal Resolution	Spatial Resolution	Data Vol/Mission
AERI	Interferometer	10 minutes	<300 m for z <3 km at 1.7 degree full angle zenith view	< 5 MB
Radiosonde	Radiosonde	2 seconds	~10 m	-
SRL	Scanning Lidar	30-60 seconds	10-300 m	10 - 20 MB

Ground-Based Instruments - Scientific Objectives

Instrument Acronym	General Hurricane	Landfalling Hurricane	TRMM Science Cal/Val	Alternate Science
AERI	Planetary boundary layer	Applicable	CERES surface budget validation	Spectroscopy validation for AIRS/NOAA/GOES sounders
Radiosonde	Applicable	Applicable	Applicable	Applicable
SRL	Applicable	Applicable	Cal/Val science with TRMM community	Cal/Val for CAMEX-3 water vapor sensors. Sub-tropical water vapor climatology.

Ground-Based Instruments - Products

Instrument Acronym	Direct Products	PI-Derived Products	Potential Products
AERI	PBL temperature and moisture profiles In-field: Downwelling spectral radiances	Boundary layer temperature and humidity profiles; Aerosol optical depth spectroscopic parameters	Infrared aerosol optical depth
Radiosonde	Atmospheric soundings of temperature, pressure, relative humidity, wind, altitude	Atmospheric soundings of temperature, pressure, relative humidity, wind, altitude	Mixing ratio, specific humidities, thermodynamic properties
SRL	Vertical profiles of water vapor mixing ratio In-field: Images of water vapor, mixing ratio, aerosol scatter, or extinct. vs. alt and time	Mixing ratio, aerosol scattering, aerosol backscatter and extinction vs altitude; precipitable water vs time	Relative humidity, precipitable water, optical thickness

Ground-Based Instruments - Planning Needs

Instrument Acronym	Critical Science Data	Mission Planning Data Needs	In-field Products
AERI	SRL, radiosonde NAST-I, LASE	GOES	Downwelling spectral radiances, planetary boundary layer temperature and moisture profiles
Radiosonde	lidar, airborne in situ moisture and temperature data	-
SRL	radiosonde, AERI, airborne instruments	WWW access	Images of water vapor, mixing ratio, aerosol scattering or extinction vs. altitude and time, precipitation water vapor

Ground-Based Instruments - Aircraft Maneuvers

Instrument Acronym	Preferred Maneuvers	Dropsondes	Unfavorable Maneuvers	Unfavorable Wx Conditions
AERI	ER-2 and DC-8 overflights	One per flight: over the ground facility	-	Rain
Radiosonde	-	-	-	High surface winds, Excessive precipitation
SRL	Regular overflights of the ground facility	One per flight: over the ground facility	-	Rain

The following links provide additional information about CAMEX-3.

Hurricane Research and Updates

Current hurricane status and information.

Aircraft Operations

Information about the aircraft that fly around, through, and over hurricanes.

Hurricane Hunters - Air Force Reserves

Hurricane Education

Informative facts, figures, tips, and trivia about hurricanes.

Hurricane Education Page - NASA Space Place

NASA Project Links

CAMEX-3 Logistics and Field Activities Page - Ames Research Center

Global Hydrometeorology Resource Center

Texas Florida Underflights Experiment - TEFLUN-A/B