Scripps Satellite Oceanography Facility TirosN/NOAA Level 0 Telemetry Data

The primary earth environmental sensors on the TirosN/NOAA
satellites are:

* TIROS Operational Vertical Sounder (TOVS). TOVS is a three
instrument system consisting of:

High Resolution Infrared Radiation Sounder (HIRS/2). This
sensor is a 20 channel instrument that measures primarily
infrared radiation. It is designed to provide information on
the temperature profile of the lower atmosphere, water vapor
content and ozone concentrations. It is a passive sensor with
a 42km along track resolution and an instantaneous field of view
(IFOV) of 1.2 degrees that corresponds to 17.4km resolution at
nadir with a total scan field of view of +/- 49.5 degrees from
nadir (approximately 2240km swath width).

Stratospheric Sounding Unit (SSU). The SSU measures the radiation
emitted by carbon dioxide gas at three different levels in the
upper atmosphere. Weighting functions are determined from
these measurements and used along with HIRS/2 and MSU
measurements to determine the temperature profile of the
upper atmosphere (25-50km). The 10 degree IFOV is equivalent
to 147km at nadir. A scan line is a composed of eight
individual 4 second steps, 32 seconds total, which result in
an underlap of 62km at nadir for this sensor. The total field
of view is +/- 35 degrees from nadir for a swath width of
approximately 1474km.

Microwave Sounding Unit (MSU). The MSU is a four channel
sensor that passively measures radiation in the 5.5mm oxygen
region. The sensor has an IFOV of 7.5 degrees or 109km at
nadir. A scan has 11 steps with a 9.47 degree scan angle
between steps and a total field of view of +/- 47.4 degrees
from nadir giving a swath width of approximately 2358km.

* Advanced Very High Resolution Radiometer (AVHRR).
The primary objective of the AVHRR instrument is to provide cloud top and sea
surface temperatures through passively measured visible, near infrared and
infrared spectral radiation bands. NOAA-6, 8, 10 and TirosN AVHRR sensors
measured in 4 spectral bands, while the NOAA 7 and 9 AVHRR instruments
measured in 5.
The AVHRR sensors has an instantaneous field of view (IFOV) that corresponds
to a ground resolution of about 1.1km at nadir, and a total scan field of view
(FOV) of +/- 55.4 degrees from nadir (approximately 2240km). The four
spectral bands (TirosN,NOAA-6,8,10) measured are; Channel 1, visible .58-.68
microns, Channel 2, near infrared, .725-1.10 microns, Channel 3, infrared,
3.55-3.99 microns and Channel 4, thermal infrared, 10.2-11.5 microns.
The five spectral bands (NOAA-7,9) measured are; Channel 1, visible .58-.68
microns, Channel 2, near infrared, .725-1.10 microns, Channel 3, infrared,
3.55-3.93 microns, Channel 4, thermal infrared, 10.2-11.3 microns and Channel
5, a second thermal infrared channel at 11.5-12.5 microns.
Measurements made by the sensor have a 10 bit precision and the data itself is
available as a Level 1b data product from National Environmental
Satellite Data and Information Services, Satellite and Data Services
Division (NESDIS/SDSD) in Suitland, Maryland.
The Data Collection and Location System, (DCS), is designed to obtain
environmental data and location from fixed or moving platforms. Its
operation is a function of user subscription to the ARGOS system of the
Centre National D'Etudes Spatiales (CNES) in France.
Integrated with the data generated by the sensors described
above is synchronization, identification, and time code information
provided by the TIROS Information Processor (TIP). Formating of the
low data rate TOVS data is accomplished by TIP where as a high data
rate processor, the Manipulated Information Rate Processor (MIRP),
formats the data generated by the AVHRR sensors.
All spacecraft instrument data is downlinked via High
Resolution Picture Transmission (HRPT). HRPT output consists of low
data rate systems or TIP output multiplexed with MIRP AVHRR output.
The TIP output includes the three instruments of the TOVS system, the
SEM output, DCS data and spacecraft telemetry.

The Scripps archive contains unprocessed, LEVEL 0 data from NIMBUS7
CZCS and NOAA series AVHRR which are identical to West Coast Time Series in
spatial and temporal coverage.
The West Coast Time Series (WCTS) project generated a time series of
coregistered sea surface temperatures (from AVHRR) and pigment
concentrations (from CZCS). Operational data coverage for the TIROSN and
the NOAA series satellites is from October 19, 1978 until the present .
Temporal resolution is 360 scans per minute with a satellite revisit time of
twice daily. Spatial coverage is over the region from 20N - 55N and
from 105W - 140W.
A note about the NOAA series satellites;
they are designed to carry near identical instrument packages and to provide
coverage of the same latitude/longitude coordinates. The planned
obsolescence feature of the series provides one or more satellites being
operational at any one time, with a replacement for the most aged satellite
being put into orbit before the retirement date of that satellite.

Operational History of the TirosN/NOAA Satellites:
start date end date
__________ ________
TirosN 1978-10-19 1980-01-20
NOAA-6 1979-06-27 1985-09-03
NOAA-7 1987-06-23 1984-12-05
NOAA-8 1981-06-23 1984-12-05
NOAA-9 1985-01-22 present
NOAA-10 1986-09-17 present

Related data sets: WCTS NIMBUS7 CZCS Pigment Concentrations.