Instrument:  Cloud Particle Imager

PI:  Paul Lawson, SPEC, Inc.  Boulder  Colorado, USA

Platform:  NCAR C-130

The data are located at:  SPEC, Incorporated
		          5401 Western Ave.  Suite B
			  Boulder, Colorado  80301
			  (970)-449-1105

The contact person is:   Paul Lawson
			 plawson@specinc.com 

Instrument description: The CPI captures high-resolution (2.3 micron) images of 
particles as they pass through the instrument sample tube.  Two intersecting 
laser beams upstream of the sample volume precisely define the depth-of-field 
so that at least one particle per frame is almost always in focus.  These beams 
make up the Particle Detection System (PDS).  As a particle enters the PDS, an 
imaging laser is triggered to freeze the motion of the particle and cast an 
image on a one-million pixel CCD camera.  The PDS continues to count the number 
of particles entering it while the computer system is busy processing the frame.

Date of observations: The CPI was active on all FIRE.ACE missions except for 
RF12 (21 July 1998).

Raw Data:  High-resolution images of "Regions of Interest" or ROIs within a 
frame, length and width dimensions of ROIs, and number of particles passing 
through PDS while system was processing frames (called total strobes).  Data 
are stored in a binary format that requires the CPIview software for reading 
the format.

Resolution of data:  The CPI can record up to 40 frames and process an 
approximate maximum of 1000 particles per second.  The resolution of the data 
is asynchronous and dependent on the cloud particle density.  Reduced data 
resolution will be at 1 Hz.

Reduced data (or derived products):
Table 1 lists the data parameters to be archived in the LaRC DAAC.  
Category 2 data for a portion of each flight will be archived by March 1999 
(see times in Analysis Status section).  The remainder of Category 2 data is 
expected to be archived by December 1999.  Category 3 data will be archived in 
the year 2000.

Table 1.  Resolution and Category of CPI Parameters 
          to be archived in the NASA LaRC DAAC.

Parameters				Resolution	Category
Total Concentration			1 Hz		2
Concentration of Water Drops		1 Hz		2
Concentration of Ice Particles	        1 Hz		2
Liquid Water Content			1 Hz		2
Ice Water Content			1 Hz		2
Water Drop Size Distribution		1 Hz		2
Ice Particle Size Distribution		1 Hz		2
Total Mean Particle Diameter		1 Hz		3
Mean Water Drop Diameter		1 Hz		3
Mean Ice Particle Diameter		1 Hz		3
Total Median Volume Diameter		1 Hz		3
Median Water Volume Diameter		1 Hz		3
Median Ice Volume Diameter		1 Hz		3
Total Effective Radius			1 Hz		3
Water Drop Effective Radius		1 Hz		3
Ice Particle Effective Radius		1 Hz		3
Phase Function				1 Hz		3
Images					TBD		3

Analysis Status:  The images taken during the following times have been manually 
categorized as either water or ice.  Category 2 products for these data will be 
archived before April 1999.  The images themselves and particle size 
distributions without artifact rejection are available in TIFF format from SPEC.


Flight   Start   Stop
RF01     23:18   23:20
RF01 	 23:54   23:58
RF02     23:27   23:29
RF03     22:40   22:42
RF04     21:52   21:54
RF05     23:02   23:04
RF06     19:20   19:22
RF07     19:03   19:05
RF08     23:37   23:39
RF09     21:57   21:59
RF10     21:50   21:52
RF11     22:54   22:56
RF12     na      na
RF13     22:40   22:42
RF14     23:22   23:24
RF15     22:22   22:24
RF16     22:45   22:47