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17
2004: Calibration of multi-satellite observations for climatic studies: Microwave sounding unit (MSU
- J. Geophys. Res
"... [1] The Microwave Sounding Units (MSU) aboard the NOAA series of polar orbiting satellites has been used by three groups to monitor the very small trend in the global tropospheric temperature over the 25-year satellite record. To obtain a homogeneous data set, each group made different calibration c ..."
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[1] The Microwave Sounding Units (MSU) aboard the NOAA series of polar orbiting satellites has been used by three groups to monitor the very small trend in the global tropospheric temperature over the 25-year satellite record. To obtain a homogeneous data set, each group made different calibration corrections of the MSUs in the form of fixed biases, and in some cases temperature-dependent adjustments, to each of the nine satellite instruments using data during the overlap periods. Up until now, however, the adjustments are empirically based. To improve the accuracy as well as our understanding of the error sources, this paper develops an alternate, physical approach for intercalibrating the MSU instruments. The paper develops a calibration model for the MSU instrument that includes the errors in the cold space and warm target measurements, as well as the nonlinear factor. Corrections for these calibration errors are estimated using a least squares minimization where the predictors are the differences between all 12 overlapping satellite measurements at low and high latitudes. After applying the calibration corrections, the zonally averaged differences between satellite instruments are no larger than 0.03 K, independent of latitude. It is also found that the tropospheric temperature trend derived
An assessment of microwave absorption models and retrievals of cloud liquid water using clearsky data,”
- J. Geophys. Res.,
, 2003
"... [1] Passive microwave radiometers have a long history in the remote sensing of atmospheric liquid and water vapor. Retrievals of these quantities are sensitive to variations in pressure and temperature of the liquid and water vapor. Rather than use a statistical or climatological approach to accoun ..."
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Cited by 5 (2 self)
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[1] Passive microwave radiometers have a long history in the remote sensing of atmospheric liquid and water vapor. Retrievals of these quantities are sensitive to variations in pressure and temperature of the liquid and water vapor. Rather than use a statistical or climatological approach to account for the natural variability in atmospheric pressure and temperature, additional information on the atmospheric profile at the time of the radiometer measurements can be directly incorporated into the retrieval process. Such an approach has been referred to in the literature as a ''physical-iterative'' solution. This paper presents an assessment of the accuracy of the column liquid water path that can be expected using such an iterative technique as a result of uncertainties in the microwave emissions from oxygen and water vapor. It is shown that the retrieval accuracy is influenced by the accuracy of the instrument measurements and the quality of the atmospheric profiles of temperature and pressure, as one would expect. However, also critical is the uncertainty in the absorption coefficients used in the underlying microwave radiative transfer model. The uncertainty in the absorption coefficients is particularly problematic in that it may well bias the liquid water retrieval. The differences between three absorption models examined in this paper are equivalent to a bias of 15 to 30 g/m 2 , depending on the total column water vapor. An examination of typical liquid water paths from the Southern Great Plains region of the United States shows that errors of this magnitude have significant implications for shortwave radiation and retrievals of cloud effective particle size. Citation: Marchand, R., T. Ackerman, E. R. Westwater, S. A. Clough, K. Cady-Pereira, and J. C. Liljegren, An assessment of microwave absorption models and retrievals of cloud liquid water using clear-sky data,
2005. Determination of an Amazon Hot Reference Target for the On-Orbit Calibration of Microwave Radiometers
"... A physically based model is developed to determine hot calibration reference brightness temperatures (TBs) over depolarized regions in the Amazon rain forest. The model can be used to evaluate the end-to-end calibration of any satellite microwave radiometer operating at a frequency between 18 and 40 ..."
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Cited by 4 (0 self)
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A physically based model is developed to determine hot calibration reference brightness temperatures (TBs) over depolarized regions in the Amazon rain forest. The model can be used to evaluate the end-to-end calibration of any satellite microwave radiometer operating at a frequency between 18 and 40 GHz and angle of incidence between nadir and 55°. The model is constrained by Special Sensor Microwave Imager (SSM/I) TBs measured at 19.35, 22.2, and 37.0 GHz at a 53 ° angle of incidence and extrapolates/interpolates those measurements to other frequencies and incidence angles. The rms uncertainty in the physically based model is estimated to be 0.57 K. For instances in which coincident SSM/I measurements are not available, an empirical formula has been fit to the physical model to provide hot reference brightness temperature as a function of frequency, incidence angle, time of day, and day of year. The empirical formula has a 0.1-K rms deviation from the physically based model for annual averaged measurements and at most a 0.6-K deviation from the model for any specific time of day or day of year. 1.
Design and Development of an Airborne Microwave Radiometer for Atmospheric Sensing
, 2011
"... Senior, MIT Lincoln abo tory visp!-C ertified by................................... ..."
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Senior, MIT Lincoln abo tory visp!-C ertified by...................................
Atmospheric Measurement Techniques
, 2012
"... First middle-atmospheric zonal wind profile measurements with a new ground-based microwave Doppler-spectro-radiometer ..."
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First middle-atmospheric zonal wind profile measurements with a new ground-based microwave Doppler-spectro-radiometer
Microwave Radiometer Calibration
, 2014
"... This study presents a new method of calibrating an orbital cross-track scanning mi-crowave radiometer using a co-located radio occultation (RO) instrument with Global Navigation Satellite Systems (GNSS). The radiometer and RO receiver periodically observe the same volume of atmosphere near the earth ..."
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This study presents a new method of calibrating an orbital cross-track scanning mi-crowave radiometer using a co-located radio occultation (RO) instrument with Global Navigation Satellite Systems (GNSS). The radiometer and RO receiver periodically observe the same volume of atmosphere near the earth's limb, allowing for overlap-ping, or collocated, measurements that can be used to calibrate the radiometer. This method leverages the benefits of both remote sensing techniques to strengthen the science returned with the goal of achieving dense geospatial sampling and highly accurate calibration. Performance analyses show that the technique is particularly well-suited for implementation on a low-cost CubeSat hosting both radiometer and RO receiver systems on the same spacecraft. We describe a validation platform for this calibration method, the Microwave Radiometer Technology Acceleration (MiRaTA)
unknown title
, 2014
"... doi:10.5194/amt-7-1619-2014 © Author(s) 2014. CC Attribution 3.0 License. An integrated approach toward the incorporation of clouds in the temperature retrievals from microwave measurements ..."
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doi:10.5194/amt-7-1619-2014 © Author(s) 2014. CC Attribution 3.0 License. An integrated approach toward the incorporation of clouds in the temperature retrievals from microwave measurements
Chalmers Publication Library Microwave
, 2013
"... radiometer to retrieve temperature profiles from the surface to the stratopause This document has been downloaded from Chalmers Publication Library (CPL). It is the author´s version of a work that was accepted for publication in: Atmospheric Measurement Techniques (ISSN: 1867-8548) Citation for the ..."
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radiometer to retrieve temperature profiles from the surface to the stratopause This document has been downloaded from Chalmers Publication Library (CPL). It is the author´s version of a work that was accepted for publication in: Atmospheric Measurement Techniques (ISSN: 1867-8548) Citation for the published paper:
CORRECTING FOR PRECIPITATION EFFECTS IN SATELLITE-BASED PASSIVE MICROWAVE TROPICAL CYCLONE INTENSITY ESTIMATES
, 2005
"... Public reporting burden for this collection of Information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments ..."
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Public reporting burden for this collection of Information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this
