Odin/OSIRIS observations of stratospheric NO&lt;sub&gt;3&lt;/sub&gt; through sunrise and sunset

Abstract. The nitrate radical (NO3) has been detected in visible limb-scattered spectra measured by the Optical Spectrograph and InfraRed Imager System (OSIRIS) on-board the Odin satellite when observing at large solar zenith angles (91–97°). Apparent slant column densities of NO3 at tangent heights between 10 and 45 km are derived via spectral fitting in the 610–680 nm window. Using observations from multiple scans spanning solar zenith angles of 91–97°, the rapid evolution of NO3 through sunrise and sunset can be traced. Slant column densities are found to be generally consistent with those simulated using a radiative transfer model with coupled photochemistry. In addition, a strong dependence of NO3 with temperature is observed. These results indicate that our current knowledge of NO3 photochemistry is generally consistent with OSIRIS observations to within the limitations of the radiative transfer modeling. Furthermore, they reveal that OSIRIS possesses signal-to-noise sufficient to make useful measurements of scattered sunlight out to solar zenith angles of 91–97° and suggest the possibility of retrieving profile information for NO3 and other species at large solar zenith angles.

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Odin/OSIRIS observations of stratospheric NO3 through sunrise and sunset

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-8-5901-2008 ◽

2008 ◽

Vol 8 (2) ◽

pp. 5901-5917

Author(s):

C. A. McLinden ◽

C. S. Haley

Keyword(s):

Radiative Transfer ◽

Strong Dependence ◽

Rapid Evolution ◽

Radiative Transfer Model ◽

Transfer Model ◽

Nitrate Radical ◽

Signal To Noise ◽

Spectral Fitting ◽

Infrared Imager ◽

Fitting In

Abstract. The nitrate radical (NO3) has been detected in visible limb-scattered spectra measured by the Optical Spectrograph and InfraRed Imager System (OSIRIS) on-board the Odin satellite when observing at large solar zenith angles (91–97°). Apparent slant column densities of NO3 at tangent heights between 10 and 45 km are derived via spectral fitting in the 590–680 nm window. Using observations from multiple scans spanning solar zenith angles of 91–97°, the rapid evolution of NO3 through sunrise and sunset can be traced. Slant column densities are found to be consistent with those simulated using a radiative transfer model with coupled photochemistry. In addition, a strong dependence of NO3 with temperature is observed. These results indicate that OSIRIS possesses signal-to-noise sufficient to make useful measurements of scattered sunlight out to solar zenith angles of 96–97° and suggests the possibility of retrieving profile information for NO3 and other species at large solar zenith angles.

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Improved OSIRIS NO2 retrieval algorithm: Description and validation

10.5194/amt-2016-277 ◽

2016 ◽

Author(s):

Christopher E. Sioris ◽

Landon A. Rieger ◽

Nicholas D. Lloyd ◽

Adam E. Bourassa ◽

Chris Z. Roth ◽

...

Keyword(s):

Radiative Transfer ◽

Nitrogen Dioxide ◽

Polar Vortex ◽

Bias Reduction ◽

Radiative Transfer Model ◽

Retrieval Algorithm ◽

Transfer Model ◽

Reconstruction Technique ◽

Spectral Fitting ◽

Infrared Imager

Abstract. A new retrieval algorithm for OSIRIS (Optical Spectrograph and Infrared Imager System) nitrogen dioxide (NO2) profiles is described and validated. The algorithm relies on spectral fitting to obtain line-of-sight (LOS) column densities of NO2 followed by inversion using an algebraic reconstruction technique and the SaskTran spherical radiative transfer model to obtain vertical profiles of local number density. The validation covers different latitudes (tropical to polar), years (2002–2012), all seasons (winter, spring, summer, and autumn), different concentrations of nitrogen dioxide (from deNOxified polar vortex to polar summer), a large range of solar zenith angles (68.6 to 90.5°) and altitudes between 10.5 and 39 km, thereby covering the full retrieval range of a typical OSIRIS NO2 profile. The use of a larger spectral fitting window than used in previous retrievals reduces retrieval uncertainties and the scatter in the retrieved profiles due to noisy radiances. Improvements are also demonstrated through the validation in terms of bias reduction at 15–17 km relative to the OSIRIS operational v3.0 algorithm. By accounting for the diurnal variation along the LOS in the two-dimensional radiative transfer model, the scatter of the differences relative to the correlative balloon NO2 profile data is reduced.

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Comparison of the University of California at Los Angeles Line-by-Line Equivalent Radiative Transfer Model and the Moderate-Resolution Transmission Model for accuracy assessment of the National Polar-Orbiting Operational Environmental Satellite System’s Visible–Infrared Imager–Radiometer Suite cloud algorithms

Applied Optics ◽

10.1364/ao.44.006274 ◽

2005 ◽

Vol 44 (29) ◽

pp. 6274 ◽

Cited By ~ 4

Author(s):

S. C. Ou ◽

K. N. Liou ◽

Y. Takano ◽

E. Wong ◽

K. Hutchison ◽

...

Keyword(s):

Los Angeles ◽

Radiative Transfer ◽

Accuracy Assessment ◽

University Of California ◽

Transmission Model ◽

Radiative Transfer Model ◽

Transfer Model ◽

Infrared Imager ◽

Moderate Resolution ◽

The University

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Radiative Transfer Modeling of Phytoplankton Fluorescence Quenching Processes

Remote Sensing ◽

10.3390/rs10081309 ◽

2018 ◽

Vol 10 (8) ◽

pp. 1309 ◽

Cited By ~ 7

Author(s):

Peng-Wang Zhai ◽

Emmanuel Boss ◽

Bryan Franz ◽

P. Werdell ◽

Yongxiang Hu

Keyword(s):

Quantum Yield ◽

Radiative Transfer ◽

Sensitivity Study ◽

Radiative Transfer Model ◽

Photochemical Quenching ◽

Transfer Model ◽

Fluorescence Signal ◽

New Space ◽

Non Photochemical Quenching ◽

Radiative Transfer Modeling

We report the first radiative transfer model that is able to simulate phytoplankton fluorescence with both photochemical and non-photochemical quenching included. The fluorescence source term in the inelastic radiative transfer equation is proportional to both the quantum yield and scalar irradiance at excitation wavelengths. The photochemical and nonphotochemical quenching processes change the quantum yield based on the photosynthetic active radiation. A sensitivity study was performed to demonstrate the dependence of the fluorescence signal on chlorophyll a concentration, aerosol optical depths and solar zenith angles. This work enables us to better model the phytoplankton fluorescence, which can be used in the design of new space-based sensors that can provide sufficient sensitivity to detect the phytoplankton fluorescence signal. It could also lead to more accurate remote sensing algorithms for the study of phytoplankton physiology.

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Improved OSIRIS NO2 retrieval algorithm: description and validation

Atmospheric Measurement Techniques ◽

10.5194/amt-10-1155-2017 ◽

2017 ◽

Vol 10 (3) ◽

pp. 1155-1168 ◽

Cited By ~ 4

Author(s):

Christopher E. Sioris ◽

Landon A. Rieger ◽

Nicholas D. Lloyd ◽

Adam E. Bourassa ◽

Chris Z. Roth ◽

...

Keyword(s):

Nitrogen Dioxide ◽

Polar Vortex ◽

Bias Reduction ◽

Radiative Transfer Model ◽

Retrieval Algorithm ◽

Transfer Model ◽

Reconstruction Technique ◽

Spectral Fitting ◽

Infrared Imager ◽

First Time

Abstract. A new retrieval algorithm for OSIRIS (Optical Spectrograph and Infrared Imager System) nitrogen dioxide (NO2) profiles is described and validated. The algorithm relies on spectral fitting to obtain slant column densities of NO2, followed by inversion using an algebraic reconstruction technique and the SaskTran spherical radiative transfer model (RTM) to obtain vertical profiles of local number density. The validation covers different latitudes (tropical to polar), years (2002–2012), all seasons (winter, spring, summer, and autumn), different concentrations of nitrogen dioxide (from denoxified polar vortex to polar summer), a range of solar zenith angles (68.6–90.5°), and altitudes between 10.5 and 39 km, thereby covering the full retrieval range of a typical OSIRIS NO2 profile. The use of a larger spectral fitting window than used in previous retrievals reduces retrieval uncertainties and the scatter in the retrieved profiles due to noisy radiances. Improvements are also demonstrated through the validation in terms of bias reduction at 15–17 km relative to the OSIRIS operational v3.0 algorithm. The diurnal variation of NO2 along the line of sight is included in a fully spherical multiple scattering RTM for the first time. Using this forward model with built-in photochemistry, the scatter of the differences relative to the correlative balloon NO2 profile data is reduced.

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Radiative Transfer Modeling of a Coniferous Canopy Characterized by Airborne Remote Sensing

Journal of Hydrometeorology ◽

10.1175/2007jhm870.1 ◽

2008 ◽

Vol 9 (2) ◽

pp. 228-241 ◽

Cited By ~ 63

Author(s):

Richard Essery ◽

Peter Bunting ◽

Aled Rowlands ◽

Nick Rutter ◽

Janet Hardy ◽

...

Keyword(s):

Radiative Transfer ◽

Laser Scanning ◽

Large Scale ◽

Forest Canopy ◽

Canopy Structure ◽

Spatial Variations ◽

Radiative Transfer Model ◽

Transfer Model ◽

Temporal Averaging ◽

Radiative Transfer Modeling

Abstract Solar radiation beneath a forest canopy can have large spatial variations, but this is frequently neglected in radiative transfer models for large-scale applications. To explicitly model spatial variations in subcanopy radiation, maps of canopy structure are required. Aerial photography and airborne laser scanning are used to map tree locations, heights, and crown diameters for a lodgepole pine forest in Colorado as inputs to a spatially explicit radiative transfer model. Statistics of subcanopy radiation simulated by the model are compared with measurements from radiometer arrays, and scaling of spatial statistics with temporal averaging and array size is discussed. Efficient parameterizations for spatial averages and standard deviations of subcanopy radiation are developed using parameters that can be obtained from the model or hemispherical photography.

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Monte Carlo Sensitivity Calculations Applied to Radiative Transfer-Combustion Coupling

Heat Transfer, Volume 3 ◽

10.1115/imece2002-33910 ◽

2002 ◽

Author(s):

M. El Hafi ◽

A. de Lataillade ◽

R. Fournier

Keyword(s):

Heat Transfer ◽

Monte Carlo ◽

Radiative Transfer ◽

Fluid Mechanics ◽

Radiative Transfer Model ◽

Transfer Model ◽

Counterflow Flame ◽

Advanced Combustion ◽

Physical Phenomena ◽

Radiative Transfer Modeling

In several applications such as meteorology or combustion, it is difficult to consider detailed radiative transfer modeling because of the high computing cost due to the numerous coupled physical phenomena such as fluid mechanics, heat transfer and chemistry. The aim of this work is to present an attempt to couple a highly accurate radiative transfer model to an advanced combustion code. This approach is based on a recently identified specific feature of Monte Carlo Methods. They provide not only the radiative source field but also its sensitivities to temperatures and concentrations with no additional random procedure. To illustrate this approach, a coupled simulation applied to a 1-D counterflow flame is presented.

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