FILE_USAGE_NCDF.TXT

The SNOE data files have passed through five steps of processing in order
to reach their final state. Levels 3 and 4 are being made available to the
science community through this dataset. The contents and layout of those
files are described in this document.

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PRODUCT: Nitric Oxide Volume Density (molecules/cm^3)
	 Level Three Data

DESCRIPTION: Orbit average files containing latitude, altitude, and
longitude resolution. The file is named 'SNOE_l3_t.ncdf', where 't' is the
type of the file, either 'geo' or 'mag' depending on the coordinate system
used to bin the data.

RESOLUTION: 5 degrees latitude, 3.3 km altitude, 24 degrees longitude

FILE CONTENTS: The NCDF file contains the following variables and
attributes:

YYYYDDD         LONG      Array[935]
LATITUDE        INT       Array[37]
LONGITUDE       INT       Array[37, 15, 935]
ALTITUDE        FLOAT     Array[17]
ORBIT           LONG      Array[15, 935]
UTC             LONG      Array[37, 15, 935]
NO              FLOAT     Array[37, 17, 15, 935]

YYYYDDD:
    type = long integer array of 935 elements
    content = date in year-day-of-year format
    units = none
latitude:
    type = integer array of 37 elements
    content = latitude center of each lat bin (Geographic)
    units = degrees
longitude:
    type = integer array of 37*15*935 elements
    content = average longitude for latitude bin
    units = degrees
    no_data = -999
altitude:
    type = float array of 17 elements
    content = Altitude scale for latitude bin profile
    units = Kilometers
orbit:
    type = long integer array of 15*935 elements
    content = orbit number of mission
    units = none
UTC:
    type = long integer array of 37*15*935 elements
    content = UTC seconds into day
    units = seconds
    no_data = -999
NO:
    type = float array of 37*17*15*935 elements
    content = volume density of nitric oxide
    units = molecules per cubic centimeter
    no_data = 0

______________________________________________________________________________
PRODUCT: Daily Averages of Nitric Oxide Density (molecules/cm^3)
	 Level Four Data

DESCRIPTION: Daily average files containing latitude and altitude binned
data.  The file is named 'SNOE_l4_t.ncdf, where 't' is the type of the
file, either 'geo' or 'mag' depending on the coordinate system used to bin
the data.

RESOLUTION: 5 degrees latitude, 3.3 km altitude.

FILE CONTENTS: The NCDF file contains the following variables and
attributes:

YYYYDDD         LONG      Array[935]
LATITUDE        INT       Array[37]
ALTITUDE        FLOAT     Array[17]
NO              FLOAT     Array[37, 17, 935]

YYYYDDD:
    type = long integer array of 935 elements
    content = date in year-day-of-year format
    units = none
latitude:
    type = integer array of 37 elements
    content = latitude center of each lat bin (Geographic)
    units = degrees
altitude:
    type = float array of 17 elements
    content = Altitude scale for latitude bin profile
    units = Kilometers
NO:
    type = float array of 37*17*935 elements
    content = volume density of nitric oxide
    units = molecules per cubic centimeter
    no_data = 0