The Advanced Technology Microwave Sounder (ATMS) is a 22-channel scanning microwave radiometer for observation of the Earth's atmosphere and surface. It is the successor to the
Advanced Microwave Sounding Unit (AMSU) on
NOAA
The National Oceanic and Atmospheric Administration (abbreviated as NOAA ) is an United States scientific and regulatory agency within the United States Department of Commerce that forecasts weather, monitors oceanic and atmospheric conditio ...
weather satellites. ATMS units have been flown on the
Suomi NPP
The Suomi National Polar-orbiting Partnership (Suomi NPP), previously known as the National Polar-orbiting Operational Environmental Satellite System Preparatory Project (NPP) and NPP-Bridge, is a weather satellite operated by the United States ...
and on the
Joint Polar Satellite System
The Joint Polar Satellite System (JPSS) is the latest generation of U.S. polar-orbiting, non-geosynchronous, environmental satellites. JPSS will provide the global environmental data used in numerical weather prediction models for forecasts, and ...
.
Applications
ATMS measurements are assimilated into
numerical weather prediction
Numerical weather prediction (NWP) uses mathematical models of the atmosphere and oceans to predict the weather based on current weather conditions. Though first attempted in the 1920s, it was not until the advent of computer simulation in th ...
models
and
atmospheric profiles retrieved by the combination of ATMS and the
Cross-track Infrared Sounder on the same satellites are useful for
synoptic scale meteorology
The synoptic scale in meteorology (also known as large scale or cyclonic scale) is a horizontal length scale of the order of 1000 kilometers (about 620 miles) or more. This corresponds to a horizontal scale typical of mid-latitude depressions (e. ...
.
Also, ATMS continues the record from its predecessor instruments
MSU MSU may refer to:
Science and technology
*Microwave sounding unit, in atmospheric science
*Mid-stream urine, used in medicine to test for urinary tract infection
*Million service units, particularly in IBM mainframe computers
*Mobile stroke unit, ...
and
AMSU of measurements in the 5-mm band of oxygen for monitoring of atmospheric temperature trends.
Instrument characteristics
All of the channels are contained within one unit, unlike the AMSU which comprises two instruments (AMSU-A and AMSU-B).
The radiometer's antenna scans underneath the satellite through
nadir
The nadir (, ; ar, نظير, naẓīr, counterpart) is the direction pointing directly ''below'' a particular location; that is, it is one of two vertical directions at a specified location, orthogonal to a horizontal flat surface.
The direc ...
, and its polarization vector rotates with the scan angle.
The sampling rate satisfies the
Nyquist criterion for channels 1-16; thus, images produced from the data are not aliased.
However, ATMS images exhibit striping, attributed to receiver gain fluctuations (1/f noise),
which can be removed by filtering the data.
Table 1 lists some characteristics of the ATMS channels.
Table 1 ATMS Radiometric characteristics
Notes
*"Vertical polarization near nadir" (also known as quasi-vertical) means that for this cross-track scanning arrangement, the E-vector is parallel to the scan direction when the antenna views nadir; "horizontal polarization" means the orthogonal direction.
*The NEDT values were measured on the Suomi-NPP unit. Two subsequent units showed similar or slightly better noise performance.
References
{{Reflist
External links
* https://www.jpss.noaa.gov/atms.html
Spacecraft instruments
Atmospheric sounding satellite sensors