The Experts below are selected from a list of 27 Experts worldwide ranked by ideXlab platform
A.e. Lipton - One of the best experts on this subject based on the ideXlab platform.
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Satellite Sounding Channel optimization in the microwave spectrum
IEEE Transactions on Geoscience and Remote Sensing, 2003Co-Authors: A.e. LiptonAbstract:A method is presented for creating a set of optimal Channels for microwave Sounding of the atmosphere. The method finds the combinations of center frequencies and bandwidths that provide optimal skill at retrieving a profile of atmospheric characteristics, such as the air temperature or water vapor concentration. The measure of optimality is a function of the degrees of freedom for the signal. The method is capable of considering several environmental regimes (e.g. latitude, season, surface type, scan angle) simultaneously while performing the optimization. Applications of the method are presented for satellite Sounding at frequencies near 60, 118, and 183 GHz. The optimized Channel sets compare favorably to Channel sets from planned operational sensors, in terms of optimality measures and retrieval performance. For tropospheric Sounding, optimal Channels have spectrally broader passbands than have typically been used in satellite Sounding instruments. For water vapor Sounding on the 183-GHz line, the number of Channels needed to achieve the full retrieval potential is shown to depend on the radiometer noise level and on the vertical structure of the water vapor profiles.
Fuzhong Weng - One of the best experts on this subject based on the ideXlab platform.
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cloud and precipitation features of super typhoon neoguri revealed from dual oxygen absorption band Sounding instruments on board fengyun 3c satellite
Geophysical Research Letters, 2015Co-Authors: Yang Han, Xiaolei Zou, Fuzhong WengAbstract:A new methodology is developed to detect the cloud structures at different vertical levels using the dual oxygen absorption bands located near 60 GHz and 118 GHz, respectively. Observations from Microwave Temperature Sounder (MWTS) and Microwave Humidity Sounder (MWHS) on board the recently launched Chinese FengYun-3C satellite are used to prove the concept. It is shown that a paired oxygen MWTS and MWHS Sounding Channel with the same peak weighting function altitude allows for detecting the vertically integrated cloud water path above that level. A cloud emission and scattering index (CESI) is defined using dual oxygen band measurements to indicate the amounts of cloud liquid and ice water paths. The CESI distributions from three paired Channels reveal unique three-dimensional structures of clouds and precipitation within Super Typhoon Neoguri that occurred in July 2014.
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Effects of Ice Decontamination on GOES-12 Imager Calibration
IEEE Transactions on Geoscience and Remote Sensing, 2013Co-Authors: Likun Wang, Fuzhong Weng, Mitch GoldbergAbstract:More precise and accurate geostationary measurements are highly needed for satellite applications. It was well known that the Geostationary Operational Environmental Satellite (GOES)-12 imager was susceptible to water-ice contamination, and thus, several decontamination efforts were carried out to remove built-up ice on the instrument during operation. The intercalibration results of GOES-12 with the Atmospheric Infrared (IR) Sounder (AIRS) and the Infrared Atmospheric Sounding Interferometer (IASI) indicate that the calibration accuracy of GOES-12 was impacted by the decontamination procedures. Relative to the AIRS and the IASI, the GOES-12 imager radiances or brightness temperatures increased in the CO2 Sounding Channel (Channel 6, 13.3 μm) and decreased in the water-vapor absorption Channel (Channel 3, 6.5 μm) but was less changed in the window Channel (Channel 4, 10.7 μm). A simple conceptual model is then proposed to give a physical explanation on the different behaviors of three IR Channels in response to the ice-removal procedures.
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introduction to suomi national polar orbiting partnership advanced technology microwave sounder for numerical weather prediction and tropical cyclone applications
Journal of Geophysical Research, 2012Co-Authors: Fuzhong Weng, Xiaolei Zou, Xing Wang, Suying Yang, M D GoldbergAbstract:[1] The Suomi National Polar-orbiting Partnership (NPP) satellite was successfully launched on 28 October 2011. On board the Suomi NPP, the Advanced Technology Microwave Sounder (ATMS) is a cross-track scanning instrument and has 22 Channels at frequencies ranging from 23 to 183 GHz which allows for probing the atmospheric temperature and moisture under clear and cloudy conditions. ATMS inherited most of the Sounding Channels from its predecessors: Advanced Microwave Sounding Unit-A (AMSU-A) and Microwave Humidity Sounder (MHS) onboard NOAA and MetOp satellites. However, ATMS has a wider scan swath and has no gaps between two consecutive orbits. It includes one new temperature Sounding Channel and two water vapor Sounding Channels and provides more details of thermal structures in lower troposphere, especially for the storm conditions such as tropical cyclones. While ATMS temperature Sounding Channels have shorter integration time and therefore higher noise than AMSU-A, the ATMS observations from their overlapping field of views are resampled to produce AMSU-A-like measurements.
T Leblanc - One of the best experts on this subject based on the ideXlab platform.
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analysis and characterization of the ssmis upper atmosphere Sounding Channel measurements
IEEE Transactions on Geoscience and Remote Sensing, 2008Co-Authors: S D Swadley, G A Poe, William Bell, Ye Hong, David Kunkee, I S Mcdermid, T LeblancAbstract:Analyses and results of the radiometric calibration accuracy and measurement characteristics of the first Defense Meteorological Satellite Program (DMSP)'s Special Sensor Microwave Imager/Sounder (SSMIS) upper atmosphere Sounding (UAS) Channels are presented herein. Launched on October 18, 2003, aboard the DMSP F-16 spacecraft in a sun-synchronous orbit, the SSMIS UAS Channels provide the first operational measurements of microwave radiation emitted by the Earth's atmosphere at mesospheric altitudes. The analysis of the SSMIS radiometer absolute calibration and stability is based upon extensive comparisons with a fully polarimetric radiative transfer model (RTM) that solves for all four Stokes parameters using coincident atmospheric temperature profiles derived from collocated Rayleigh lidar observations merged with the European Centre for Medium-Range Weather Forecasting temperature analyses and climatological data sets. The resulting merged profiles provide a physically consistent temperature profile from the surface to 100 km, as needed by the RTMs. The results presented herein of the SSMIS instrument show that significant hardware and scientific technical challenges arise from microwave temperature Sounding of the mesosphere. These include the following: 1) addressing the impact of large noise-equivalent temperature difference associated with narrow Channel bandwidths; 2) achieving high Channel center-frequency stability; 3) compensation of large spacecraft-induced Doppler shift; 4) better characterization of the Zeeman splitting of the oxygen absorption lines; 5) development of a fast polarimetric RTM; and 6) designing stable and accurate on-orbit radiometric calibration targets. Results to date show that the uncertainties of the calibration accuracy of the SSMIS UAS Channels are consistent and in agreement with the limits derived for the SSMIS UAS Channels and with the simulated radiances derived from the merged lidar profiles.
Mitch Goldberg - One of the best experts on this subject based on the ideXlab platform.
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Effects of Ice Decontamination on GOES-12 Imager Calibration
IEEE Transactions on Geoscience and Remote Sensing, 2013Co-Authors: Likun Wang, Fuzhong Weng, Mitch GoldbergAbstract:More precise and accurate geostationary measurements are highly needed for satellite applications. It was well known that the Geostationary Operational Environmental Satellite (GOES)-12 imager was susceptible to water-ice contamination, and thus, several decontamination efforts were carried out to remove built-up ice on the instrument during operation. The intercalibration results of GOES-12 with the Atmospheric Infrared (IR) Sounder (AIRS) and the Infrared Atmospheric Sounding Interferometer (IASI) indicate that the calibration accuracy of GOES-12 was impacted by the decontamination procedures. Relative to the AIRS and the IASI, the GOES-12 imager radiances or brightness temperatures increased in the CO2 Sounding Channel (Channel 6, 13.3 μm) and decreased in the water-vapor absorption Channel (Channel 3, 6.5 μm) but was less changed in the window Channel (Channel 4, 10.7 μm). A simple conceptual model is then proposed to give a physical explanation on the different behaviors of three IR Channels in response to the ice-removal procedures.
S D Swadley - One of the best experts on this subject based on the ideXlab platform.
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analysis and characterization of the ssmis upper atmosphere Sounding Channel measurements
IEEE Transactions on Geoscience and Remote Sensing, 2008Co-Authors: S D Swadley, G A Poe, William Bell, Ye Hong, David Kunkee, I S Mcdermid, T LeblancAbstract:Analyses and results of the radiometric calibration accuracy and measurement characteristics of the first Defense Meteorological Satellite Program (DMSP)'s Special Sensor Microwave Imager/Sounder (SSMIS) upper atmosphere Sounding (UAS) Channels are presented herein. Launched on October 18, 2003, aboard the DMSP F-16 spacecraft in a sun-synchronous orbit, the SSMIS UAS Channels provide the first operational measurements of microwave radiation emitted by the Earth's atmosphere at mesospheric altitudes. The analysis of the SSMIS radiometer absolute calibration and stability is based upon extensive comparisons with a fully polarimetric radiative transfer model (RTM) that solves for all four Stokes parameters using coincident atmospheric temperature profiles derived from collocated Rayleigh lidar observations merged with the European Centre for Medium-Range Weather Forecasting temperature analyses and climatological data sets. The resulting merged profiles provide a physically consistent temperature profile from the surface to 100 km, as needed by the RTMs. The results presented herein of the SSMIS instrument show that significant hardware and scientific technical challenges arise from microwave temperature Sounding of the mesosphere. These include the following: 1) addressing the impact of large noise-equivalent temperature difference associated with narrow Channel bandwidths; 2) achieving high Channel center-frequency stability; 3) compensation of large spacecraft-induced Doppler shift; 4) better characterization of the Zeeman splitting of the oxygen absorption lines; 5) development of a fast polarimetric RTM; and 6) designing stable and accurate on-orbit radiometric calibration targets. Results to date show that the uncertainties of the calibration accuracy of the SSMIS UAS Channels are consistent and in agreement with the limits derived for the SSMIS UAS Channels and with the simulated radiances derived from the merged lidar profiles.