B. Cairns - Academia.edu (original) (raw)
Papers by B. Cairns
Journal of the Atmospheric Sciences, 2002
Journal of Quantitative Spectroscopy and Radiative Transfer, 2009
Climatic Change, 1995
... Although efforts to measure integrated reflected solar and emitted thermal fluxes are underwa... more ... Although efforts to measure integrated reflected solar and emitted thermal fluxes are underway (Kandel, 1990), measurement of changes in the spectral distribution of the radiation are required to provide diagnostic information about causes of flux changes. Monitoring Rationale ...
Bulletin of the American Meteorological Society, 2007
The NASA Glory mission is intended to facilitate and improve upon long-term monitoring of two key... more The NASA Glory mission is intended to facilitate and improve upon long-term monitoring of two key forcings influencing global climate. One of the mission's principal objectives is to determine the global distribution of detailed aerosol and cloud properties with unprecedented accuracy, thereby facilitating the quantification of the aerosol direct and indirect radiative forcings. The other is to continue the 28-yr record of satellite-based measurements of total solar irradiance from which the effect of solar variability on the Earth's climate is quantified. These objectives will be met by flying two state-of-the-art science instruments on an Earth-orbiting platform. Based on a proven technique demonstrated with an aircraft-based prototype, the Aerosol Polarimetry Sensor (APS) will collect accurate multiangle photopolarimetric measurements of the Earth along the satellite ground track within a wide spectral range extending from the visible to the shortwave infrared. The Total ...
2004 IEEE Aerospace Conference Proceedings (IEEE Cat. No.04TH8720)
The scan mechanism of the HyperSpecTIR hyperspectral instrument has been modified to allow BRDF m... more The scan mechanism of the HyperSpecTIR hyperspectral instrument has been modified to allow BRDF measurements from an airborne platform. The HyperSpecTIR is a flexible, airborne hyperspectral imager capable of on-the-fly programmability. Such measurements afford the opportunity to study geometric and spectral properties of natural scenes such as fields and canopies, as well as man-made substances such as composite materials and
Optics Communications, 1987
SPIE Proceedings, 1997
It is shown that it is possible to retrieve aerosol properties using polarization measurements fr... more It is shown that it is possible to retrieve aerosol properties using polarization measurements from satellite, or aircraft even when the surface polarization is significant and unknown. This extends the domain for which it is possible to intercompare ground and aircraft/satellite estimates of aerosol properties and allows the retrieval of aerosol properties to be made above bare soil surfaces.
Algorithms and Technologies for Multispectral, Hyperspectral, and Ultraspectral Imagery VIII, 2002
The NASA Langley Research Center B200 aircraft which participated in the ARCTAS 2008 campaign car... more The NASA Langley Research Center B200 aircraft which participated in the ARCTAS 2008 campaign carried the passive Research Scanning Polarimeter (RSP) and the active High Spectral Resolution Lidar (HSRL) instrumentation during the summer deployment. These sensors have complementary retrieval capabilities, with the RSP measurements providing a detailed microphysics retrieval capability with limited sensitivity to the details of vertical structure, and the HSRL providing high resolution vertical profile information with a limited (5 pieces of information) microphysical capability. The ideal outcome of a retrieval is to provide the aerosol/cloud model (i.e., vertical distribution of properties) which fits the datasets best in a statistical sense. Within the Maximum A-posteriori Probability (MAP) method an a-priori knowledge of the state is combined with a chi2-statistics measuring the distance between observations and simulation, weighted through a proper estimate of the errors involved...
The ability to detect and attribute climate forcings due to aerosol and surface albedo changes in... more The ability to detect and attribute climate forcings due to aerosol and surface albedo changes in a rapidly changing global climate is an important goal of the CLARREO mission. While spectral polarimetric measurements appear to offer the best prospects for achieving this goal, important questions remain as to the type of information content that can be extracted from polarimetric data. Our approach to study this problem is to make forward calculations with the CLARREO Spectral Polarimetric Simulator using the GISS ModelE aerosol climatology as the aerosol input model. This provides a realistic, although idealized, aerosol mixture consisting of sulfate, nitrate, sea salt, mineral dust, organic, and black carbon components (based on chemistry-transport model simulations) with realistic size, height, and relative humidity dependence. By choosing the ARM SGP Site, we have available at SGP a well-defined spectral surface albedo, as well as a whole suite of ancillary instruments, includin...
ABSTRACT The Hyperspectral Polarimeter for Aerosol Re-trievals (HySPAR) acquires a 120 degree spa... more ABSTRACT The Hyperspectral Polarimeter for Aerosol Re-trievals (HySPAR) acquires a 120 degree spatial, full-Stokes (i.e. including V) line image over 480-960 nm in a single snapshot with no moving parts. Unlike other snapshot polarimeters that typically use multiple boresighted beams or micro-polarizer pixel masks, HySPAR uses an arrangement of birefringent crystals to impart a polarization dependent modulation on the measured spectrum. The modulated spectra can be inverted to yield Stokes spectra. Preliminary airborne measurement results from the Megacity Initiative: Local and Global Research Observa-tions (MILAGRO) campaign will be presented. HySPAR Stokes imagery will be compared to that of the Research Scanning Polarimeter (RSP). These data were acuired during coordinated ight paths of the two aircraft carrying the sensors.
Remote Sensing in Atmospheric Pollution Monitoring and Control, 2004
Determination of aerosol optical depth from satellite remote sensing measurements is extremely co... more Determination of aerosol optical depth from satellite remote sensing measurements is extremely complex due to the large variability of aerosol optical properties. Significant simplification occurs when measurements are taken over water since the ocean reflection signal can be taken ...
Journal of the Atmospheric Sciences, 2002
Journal of Quantitative Spectroscopy and Radiative Transfer, 2009
Climatic Change, 1995
... Although efforts to measure integrated reflected solar and emitted thermal fluxes are underwa... more ... Although efforts to measure integrated reflected solar and emitted thermal fluxes are underway (Kandel, 1990), measurement of changes in the spectral distribution of the radiation are required to provide diagnostic information about causes of flux changes. Monitoring Rationale ...
Bulletin of the American Meteorological Society, 2007
The NASA Glory mission is intended to facilitate and improve upon long-term monitoring of two key... more The NASA Glory mission is intended to facilitate and improve upon long-term monitoring of two key forcings influencing global climate. One of the mission's principal objectives is to determine the global distribution of detailed aerosol and cloud properties with unprecedented accuracy, thereby facilitating the quantification of the aerosol direct and indirect radiative forcings. The other is to continue the 28-yr record of satellite-based measurements of total solar irradiance from which the effect of solar variability on the Earth's climate is quantified. These objectives will be met by flying two state-of-the-art science instruments on an Earth-orbiting platform. Based on a proven technique demonstrated with an aircraft-based prototype, the Aerosol Polarimetry Sensor (APS) will collect accurate multiangle photopolarimetric measurements of the Earth along the satellite ground track within a wide spectral range extending from the visible to the shortwave infrared. The Total ...
2004 IEEE Aerospace Conference Proceedings (IEEE Cat. No.04TH8720)
The scan mechanism of the HyperSpecTIR hyperspectral instrument has been modified to allow BRDF m... more The scan mechanism of the HyperSpecTIR hyperspectral instrument has been modified to allow BRDF measurements from an airborne platform. The HyperSpecTIR is a flexible, airborne hyperspectral imager capable of on-the-fly programmability. Such measurements afford the opportunity to study geometric and spectral properties of natural scenes such as fields and canopies, as well as man-made substances such as composite materials and
Optics Communications, 1987
SPIE Proceedings, 1997
It is shown that it is possible to retrieve aerosol properties using polarization measurements fr... more It is shown that it is possible to retrieve aerosol properties using polarization measurements from satellite, or aircraft even when the surface polarization is significant and unknown. This extends the domain for which it is possible to intercompare ground and aircraft/satellite estimates of aerosol properties and allows the retrieval of aerosol properties to be made above bare soil surfaces.
Algorithms and Technologies for Multispectral, Hyperspectral, and Ultraspectral Imagery VIII, 2002
The NASA Langley Research Center B200 aircraft which participated in the ARCTAS 2008 campaign car... more The NASA Langley Research Center B200 aircraft which participated in the ARCTAS 2008 campaign carried the passive Research Scanning Polarimeter (RSP) and the active High Spectral Resolution Lidar (HSRL) instrumentation during the summer deployment. These sensors have complementary retrieval capabilities, with the RSP measurements providing a detailed microphysics retrieval capability with limited sensitivity to the details of vertical structure, and the HSRL providing high resolution vertical profile information with a limited (5 pieces of information) microphysical capability. The ideal outcome of a retrieval is to provide the aerosol/cloud model (i.e., vertical distribution of properties) which fits the datasets best in a statistical sense. Within the Maximum A-posteriori Probability (MAP) method an a-priori knowledge of the state is combined with a chi2-statistics measuring the distance between observations and simulation, weighted through a proper estimate of the errors involved...
The ability to detect and attribute climate forcings due to aerosol and surface albedo changes in... more The ability to detect and attribute climate forcings due to aerosol and surface albedo changes in a rapidly changing global climate is an important goal of the CLARREO mission. While spectral polarimetric measurements appear to offer the best prospects for achieving this goal, important questions remain as to the type of information content that can be extracted from polarimetric data. Our approach to study this problem is to make forward calculations with the CLARREO Spectral Polarimetric Simulator using the GISS ModelE aerosol climatology as the aerosol input model. This provides a realistic, although idealized, aerosol mixture consisting of sulfate, nitrate, sea salt, mineral dust, organic, and black carbon components (based on chemistry-transport model simulations) with realistic size, height, and relative humidity dependence. By choosing the ARM SGP Site, we have available at SGP a well-defined spectral surface albedo, as well as a whole suite of ancillary instruments, includin...
ABSTRACT The Hyperspectral Polarimeter for Aerosol Re-trievals (HySPAR) acquires a 120 degree spa... more ABSTRACT The Hyperspectral Polarimeter for Aerosol Re-trievals (HySPAR) acquires a 120 degree spatial, full-Stokes (i.e. including V) line image over 480-960 nm in a single snapshot with no moving parts. Unlike other snapshot polarimeters that typically use multiple boresighted beams or micro-polarizer pixel masks, HySPAR uses an arrangement of birefringent crystals to impart a polarization dependent modulation on the measured spectrum. The modulated spectra can be inverted to yield Stokes spectra. Preliminary airborne measurement results from the Megacity Initiative: Local and Global Research Observa-tions (MILAGRO) campaign will be presented. HySPAR Stokes imagery will be compared to that of the Research Scanning Polarimeter (RSP). These data were acuired during coordinated ight paths of the two aircraft carrying the sensors.
Remote Sensing in Atmospheric Pollution Monitoring and Control, 2004
Determination of aerosol optical depth from satellite remote sensing measurements is extremely co... more Determination of aerosol optical depth from satellite remote sensing measurements is extremely complex due to the large variability of aerosol optical properties. Significant simplification occurs when measurements are taken over water since the ocean reflection signal can be taken ...