Chapter 2
Passive Microwave Remote Sensing
of the Ocean: An Overview
Chelle L. Gentemann, Frank J. Wentz, Marty Brewer,
Kyle Hilburn, and Deborah Smith
2.1 Introduction
Global geophysical measurements from passive microwave radiometers provide key
variables for scientists and forecasters. The daily measurements of Sea Surface
Temperature (SST), wind speed, water vapor, cloud liquid water, rain rate, and,
in the future, Sea Surface Salinity (SSS) over the oceans has provided data sets
used to significantly improve our understanding of the Earth system. The data are
used extensively in numerical weather prediction, hurricane forecasting, climate
monitoring, ecosystem forecasting and fisheries; as well as for climate, weather,
oceanographic, metorological and ecosystem research. The measurement accuracy
is tied to the evolution of both the calibration methods and retrieval algorithms.
2.2 Background
Designed to measure rainfall, the first Passive MicroWave (PMW) radiometer
was launched in December 1972 on the Nimbus-5 satellite. After a short gap,
PMW radiometers have been continuously observing the oceans since the launch
of Nimbus-7 in 1978. This instrument was followed by the Special Sensing
Microwave Imager (SSM/I) series. More recently, several other PMW radiometers
have been launched on National Aeronautics and Space Administration (NASA),
Japan Aerospace eXploration Agency (JAXA), and European Space Agency (ESA)
satellites (Table 2.1).
The Electrically Scanning Microwave Radiometer (ESMR) on Nimbus-5 had
only one channel at 19.35 GHz and was capable of measuring both rainfall and sea
ice detection.
From October 1978 to July 1987, the Nimbus-7 Scanning Multi-channel
Microwave Radiometer (SMMR) measured at 6.6, 10.7, 18.0, 21.0, and 37 GHz in
C.L. Gentemann (B)
Remote Sensing Systems, Santa Rosa, CA 95401, USA
e-mail: gentemann@remss.com
13
V. Barale et al. (eds.), Oceanography from Space,
DOI 10.1007/978-90-481-8681-5_2, C
Springer Science+Business Media B.V. 2010
Passive Microwave Remote Sensing
of the Ocean: An Overview
Chelle L. Gentemann, Frank J. Wentz, Marty Brewer,
Kyle Hilburn, and Deborah Smith
2.1 Introduction
Global geophysical measurements from passive microwave radiometers provide key
variables for scientists and forecasters. The daily measurements of Sea Surface
Temperature (SST), wind speed, water vapor, cloud liquid water, rain rate, and,
in the future, Sea Surface Salinity (SSS) over the oceans has provided data sets
used to significantly improve our understanding of the Earth system. The data are
used extensively in numerical weather prediction, hurricane forecasting, climate
monitoring, ecosystem forecasting and fisheries; as well as for climate, weather,
oceanographic, metorological and ecosystem research. The measurement accuracy
is tied to the evolution of both the calibration methods and retrieval algorithms.
2.2 Background
Designed to measure rainfall, the first Passive MicroWave (PMW) radiometer
was launched in December 1972 on the Nimbus-5 satellite. After a short gap,
PMW radiometers have been continuously observing the oceans since the launch
of Nimbus-7 in 1978. This instrument was followed by the Special Sensing
Microwave Imager (SSM/I) series. More recently, several other PMW radiometers
have been launched on National Aeronautics and Space Administration (NASA),
Japan Aerospace eXploration Agency (JAXA), and European Space Agency (ESA)
satellites (Table 2.1).
The Electrically Scanning Microwave Radiometer (ESMR) on Nimbus-5 had
only one channel at 19.35 GHz and was capable of measuring both rainfall and sea
ice detection.
From October 1978 to July 1987, the Nimbus-7 Scanning Multi-channel
Microwave Radiometer (SMMR) measured at 6.6, 10.7, 18.0, 21.0, and 37 GHz in
C.L. Gentemann (B)
Remote Sensing Systems, Santa Rosa, CA 95401, USA
e-mail: gentemann@remss.com
13
V. Barale et al. (eds.), Oceanography from Space,
DOI 10.1007/978-90-481-8681-5_2, C
Springer Science+Business Media B.V. 2010