The AVHRR-and-VIIRS CoastWatch SST products supply users with
operational satellite data, processed using TeraScan software and CoastWatch
utilities. All data are contained
in subdirectories named according to the date, time (UTC), satellite,
and ground station for the satellite pass. Each directory contains a
number of files:
.hdf
CoastWatch product data in Hierarchical Data Format (HDF).
Large files approximately 40-60 Mb are full pass swath projection
data, and are mainly for use by research personnel at NOAA. Smaller
files approximately 1-10 Mb in size are mapped projection data.
These are the standard CoastWatch product files viewable in
CDAT.
.jpg
JPEG browse image for the full pass swath projection.
.log
Data processing log file showing details on ingest, automatic
navigation, SST equations and coefficients, and so on.
.inf
Information file containing pass parameters such as dimensions,
date, time, spacecraft attitude, and GCP mesh coordinates.
The mapped HDF data is divided into files for a number of CoastWatch
regions of interest, where each file contains multiple data variables.
Mapped HDF files may be downloaded and viewed using the CoastWatch
Utilities software, which includes the graphical CoastWatch Data
Analysis Tool (CDAT), available from:
Ground station where the data was captured:
mo = Monterey, CA
gc = Gilmore Creek, AK
wi = Wallops Island, VA
eb = Ewa Beach, HI
mi = Miami, FL
Data File Naming Conventions
Both mapped and swath HDF product files are named using the same
convention with the following template:
YYYY_DDD_HHMM_SSS_RR.FMT
where:
YYYY
Full year with century
DDD
Julian day [001-366]
HHMM
Hour and minute in Greenwich (UTC) time
SSS
Satellite code (see above for examples)
RR
CoastWatch region code
FMT
File format
The current CoastWatch region codes are as follows:
Region code
Region description
Projection type
Map projection
gc
Gilmore Creek, AK
swath
n/a
aa
Alaska Sitka
mapped
Polar stereographic
ax
Alaska south
mapped
Polar stereographic
ay
Alaska west
mapped
Polar stereographic
az
Alaska north
mapped
Polar stereographic
mi
Miami, FL
swath
n/a
ce
Caribbean east
mapped
Mercator
cw
Caribbean west
mapped
Mercator
mr
Gulf of Mexico
mapped
Mercator
wa
West Coast Acapulco
mapped
Mercator
wi
Wallops Island, VA
swath
n/a
er
East Coast north
mapped
Mercator
sr
East Coast south
mapped
Mercator
sb
East Coast Bermuda
mapped
Mercator
gr
Great Lakes regional
mapped
Mercator
eb
Ewa Beach, HI
swath
n/a
hr
Hawaii regional
mapped
Mercator
mo
Monterey, CA
swath
n/a
wj
West Coast Baja
mapped
Mercator
wn
West Coast north
mapped
Mercator
ws
West Coast south
mapped
Mercator
sl
Great Salt Lake
mapped
Mercator
Variable Naming Conventions
Each HDF data file contains multiple data variables stored using
the HDF Scientific Data Sets (SDS) model. Each variable is named
according to the data that it represents as follows:
avhrr_ch1
AVHRR channel 1 albedo (%)
avhrr_ch2
AVHRR channel 2 albedo (%)
avhrr_ch3a
AVHRR channel 3a albedo (%)
avhrr_ch3
AVHRR channel 3 brightness temperature (deg C)
avhrr_ch4
AVHRR channel 4 brightness temperature (deg C)
avhrr_ch5
AVHRR channel 5 brightness temperature (deg C)
sst
Moisture corrected sea-surface-temperature (deg C)
cloud
8-bit CLAVR ocean cloud mask:
Daytime
Bit 1: Reflective Gross Cloud Test
Bit 2: Reflectance Uniformity Test
Bit 3: Reflectance Ratio Cloud Test
Bit 4: Channel 3 Albedo Test
Bit 5: Thermal Uniformity Test
Bit 6: Four Minus Five Test
Bit 7: Thermal Gross Cloud Test
Nighttime
Bit 1: Thermal Gross Cloud Test
Bit 2: Thermal Uniformity Test
Bit 3: Uniform Low Stratus Test
Bit 4: Four Minus Five Test
Bit 5: Cirrus Test
Bit 6: Channel 3B Albedo Test
Bit 7: Channel 3B Albedo Uniformity Test
sat_zenith
Satellite zenith angle (degrees)
sun_zenith
Solar zenith angle (degrees)
rel_azimuth
Relative azimuth angle (degrees)
graphics
8-bit graphics layers:
Bit 1: Fill flag
Bit 2: Latitude/longitude grid
Bit 3: Coastline and political geography lines
Bit 4: Land/water flag
Bits 5-8: Unused
Feedback
For questions or comments regarding these products, please contact
Sheekela.Baker-Yeboah@noaa.gov.
