First ISCCP Regional Experiment (FIRE) Cirrus Phase II University of North Dakota Citation Aircraft Microphysical Data

The First ISCCP Regional Experiments have been designed to improve data products and cloud/radiation parameterizations used in general circulation models (GCMs). Specifically, the goals of FIRE are (1) to improve basic understanding of the interaction of physical processes in determining life cycles of cirrus and marine stratocumulus systems and the radiative properties of these clouds during their life cycles and (2) to investigate the interrelationships between the ISCCP data, GCM parameterizations, and higher space and time resolution cloud data.To-date, four intensive field-observation periods were planned and executed: a cirrus IFO (October 13-November 2, 1986); a marine stratocumulus IFO off the southwestern coast of California (June 29-July 20, 1987); a second cirrus IFO in southeastern Kansas (November 13-December 7, 1991); and a second marine stratocumulus IFO in the eastern North Atlantic Ocean (June 1-June 28, 1992). Each mission combined coordinated satellite, airborne, and surface observations with modeling studies to investigate the cloud properties and physical processes of the cloud systems. The University of North Dakota owns and operates a Cessna Citation II aircraft (N77ND) for the purpose of atmospheric research. This aircraft type has a number of design and performance characteristics which make it an ideal platform for a wide range of atmospheric studies. A series of structural modifications have been made to the basic airplane. These include the following: pylons under the wing tips for a variety of probes in the undisturbed air flow away from the fuselage; a nose boom for wind measurement; a heated radome to prevent ice accumulation on the nose area; special mounts for upward and downward looking radiometers; side-facing camera mounts for time-lapse cameras; optically-flat glass windows for photography; and an air inlet port for air sampling inside the pressurized cabin. The research instrumentation available on the Citation for the second Cirrus IFO is described below. For more information about the UND Citation see http://cumulus.atmos.und.edu/ Cloud microphysical measurements were derived from data taken by the University of North Dakota Citation aircraft PMS 2D-C and 2D-P probes during the FIRE Cirrus IFO - II. Following are a list of parameters collected: VARIABLE DESCRIPTION UNITS ------------------------------------------------------------------------------- IT1,IT2 MEASUREMENT TIME INTERVAL HH/MM/SS PS STATIC PRESSURE mb TEMP AMBIENT TEMPERATURES degrees C ALT PRESSURE ALTITUDE m USTAR VERTICAL VELOCITY NEEDED TO KEEP THE cm/s RELATIVE HUMIDITY CONSTANT DBARM MEDIAN PARTICLE MASS WEIGHTED DIAMETER cm DMAX MAXIMUM PARTICLE DIAMETER cm W1 DIFFUSIONAL GROWTH RATE IN CHANNEL 1 g/sec W2 DIFFUSIONAL GROWTH RATE IN CHANNEL 2 g/sec W3 DIFFUSIONAL GROWTH RATE IN CHANNEL 3 g/sec W4 DIFFUSIONAL GROWTH RATE IN CHANNEL 4 g/sec WTOT TOTAL DIFFUSTIONAL GROWTH RATE g/sec DT8 DEPLETION TIME (8 micron droplets) sec DT12 DEPLETION TIME (12 micron droplets) sec TMASS1 IWC IN CHANNEL 1 g/m^3 TMASS2 IWC IN CHANNEL 2 g/m^3 DPTC DEW POINT TEMPERATURE (EG&G) degreesC RH RELATIVE HUMIDITY (EG&G) % RIWC ICE WATER CONTENT g/m^3 XM1 ICE WATER CONTENT BASED ON SNOW HABIT g/m^3 XM2 ICE WATER CONTENT BASED ON SMALL SNOW g/m^3 HABIT XM3 ICE WATER CONTENT BASED ON LARGE SNOW g/m^3 HABIT R PRECIPITATION RATE mm/hr DBZ RADAR REFLECTIVITY FACTOR decibels VBAR MEAN REFLECTIVITY WEIGHTED WITH THE cm/s TERMINAL VELOCITY TTCONC TOTAL PARTICLE CONCENTRATION #/L CBIN1 PARTICLE CONCENTRATION WITHIN THE RANGE LE 200 #/L CBIN2 PARTICLE CONCENTRATION WITHIN 200-500 #/L THE RANGE CBIN3 PARTICLE CONCENTRATION WITHIN THE 500-800 #/L RANGE CBIN4 PARTICLE CONCENTRATION WITHIN THE #/L RANGE GT 800 CE8 COLLECTION EFFICIENCY (8 micron none droplets) CE12 COLLECTION EFFICIENCY (12 micron none droplets) TMASS3 IWC IN CHANNEL 3 g/m^3 TMASS4 IWC IN CHANNEL 4 g/m^3 TIMP # OF CRYSTAL-CRYSTAL COLUMNS sec^(1-) RHORH WATER VAPOR DENSITY g/cm^3 SI SUPERSATURATION WITH RESPECT TO ICE % SW SUPERSATURATION WITH RESPECT TO WATER % LAMBDA COEFFICIENTS USED TO FIT THE EQUATION #/cm^3 NZERO N=N0*EXP(-LAMBDA*D) #/L/mm RSQ COEFFICIENT OF THE FIT none ICP PROBE TYPE (C OR P) none

Tags: earth-science-altitude-atmosphere-barometric-altitude, earth-science-atmospheric-pressure-atmosphere-static-pressure, earth-science-atmospheric-temperature-atmosphere-surface-temperature-air-temperature, earth-science-atmospheric-water-vapor-atmosphere-water-vapor-indicators-dew-point-temperature, earth-science-atmospheric-water-vapor-atmosphere-water-vapor-indicators-humidity, earth-science-atmospheric-water-vapor-atmosphere-water-vapor-indicators-water-vapor, earth-science-atmospheric-winds-atmosphere-wind-dynamics-vertical-wind-velocity-speed, earth-science-clouds-atmosphere-cloud-microphysics-cloud-droplet-concentration-size, earth-science-clouds-atmosphere-cloud-microphysics-cloud-liquid-water-ice, earth-science-precipitation-atmosphere-precipitation-rate, earth-science-radar-spectral-engineering-radar-reflectivity
Organization: National Aeronautics and Space Administration