Surface and aerosol retrieval from S5P and S4: baseline requirements and expected performance

Sentinel-4 and Sentinel-5p instruments provide hyperspectral measurements in UV, VIS and infrared spectral range. Though the main purpose of the satellites is trace gas characterization, both instruments are capable of aerosol and surface characterization. In particular, S4 and S5p measurements in UV have unique information about absorption and elevation properties of aerosol. Moreover, measurements in wide spectral range are very sensitive to aerosol size and surface type. On one hand, aerosol and surface characteristics are important input parameters for different trace gases such as ozone, NO2, BrO, CH2O, H2O, CO2, CO, and CH4. On another hand, aerosol and surface characteristics are very important on their own for climate studies, air pollution and surface monitoring.The quantitative characterization of aerosol (AOD (Aerosol Optical Depth), aerosol type) and surface properties (BRDF (Bidirectional Reflectance Distribution Function)) from Sentinel-4 and Sentinel-5p instruments is a topic for several ESA/EUMETSAT projects. In particular, in the framework of S5P+I AOD/BRDF project an innovative algorithm will be developed which integrates the advanced GRASP algorithm (Dubovik et al. 2011, 2014) with the heritage AOD and DLER algorithm previously applied to TOMS, GOME(-2), SCIAMACHY and OMI sensors (Tilstra et al., 2017). Innovative GRASP algorithm is expected to provide surface BRDF and AOD with the accuracy required by most trace gas retrieval algorithms.Here the requirements on aerosol and surface characterization from S4 and S5p instruments will be analyzed. On the basis of inversion results from the synthetic (S4) and real (S5p) measurements we discuss how expected AOD and BRDF accuracy from the innovative and GRASP/S4 algorithms meet these requirements. New advanced possibility of aerosol and surface characterization with GRASP from S5p instrument will be discussed.References<ol><li>Dubovik, O., et al., &#8220;Statistically optimized inversion algorithm for enhanced retrieval of aerosol properties from spectral multi-angle polarimetric satellite observations&#8221;, Atmos. Meas. Tech., 4, 975-1018, 2011.</li> <li>Dubovik, O., et al. &#8220;GRASP: a versatile algorithm for characterizing the atmosphere&#8221;, SPIE: Newsroom, doi:10.1117/2.1201408.005558, Published Online: http://spie.org/x109993.xml, September 19, 2014.</li> <li>Tilstra, L. G., et al., &#8220;Surface reflectivity climatologies from UV to NIR determined from Earth observations by GOME-2 and SCIAMACHY&#8221;, J. Geophys. Res. Atmos., 122, 4084&#8211;4111.</li> </ol>

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Surface and aerosol retrieval from S5P/TROPOMI: new possibilities and expected performance

10.5194/egusphere-egu21-14770 ◽

2021 ◽

Author(s):

Pavel Litvinov ◽

Oleg Dubovik ◽

Cheng Chen ◽

Anton Lopatin ◽

Tatyana Lapyonok ◽

...

Keyword(s):

Spectral Range ◽

Surface Characterization ◽

Trace Gases ◽

Trace Gas ◽

Surface Type ◽

Aerosol Retrieval ◽

Infrared Spectral Range ◽

Expected Performance ◽

Retrieval Algorithms ◽

Infrared Spectral

Sentinel-5p/TROPOMI instrument provides hyperspectral measurements in UV, VIS and infrared spectral range. Though the main purpose of the satellite is trace gases characterization, it is capable of aerosol and surface studies. In particular, S5p/TROPOMI measurements in UV provide unique information about absorption and elevation properties of aerosol. Moreover, measurements in wide spectral range are very sensitive to aerosol size and surface type.In the framework of ESA S5P+I AOD/BRDF project an innovative algorithm for aerosol and surface retrieval from S5p/TROPOMI instrument is being developed. It integrates the advanced GRASP algorithm with the heritage AOD and DLER algorithm previously applied to TOMS, GOME(-2), SCIAMACHY and OMI sensors. The innovative algorithm is expected to provide surface BRDF and AOD with the accuracy required by most trace gas retrieval algorithms.Here we present the results of aerosol and surface validation and inter-comparison obtained within ESA S5p+I project. New advanced possibility of aerosol and surface characterization from S5p/TROPOMI instrument will be discussed.

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Optics and photonics. Optical materials and components. Characterization of optical materials used in the infrared spectral range from 0,78 μm to 25 μm

10.3403/30192062u ◽

2015 ◽

Keyword(s):

Spectral Range ◽

Optical Materials ◽

Infrared Spectral Range ◽

Infrared Spectral ◽

Materials Used

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Post-Processing and Surface Characterization of Additively Manufactured Stainless Steel 316L Lattice: Implications for BioMedical Use

Materials ◽

10.3390/ma14061376 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1376

Author(s):

Alex Quok An Teo ◽

Lina Yan ◽

Akshay Chaudhari ◽

Gavin Kane O’Neill

Keyword(s):

Surface Roughness ◽

Stainless Steel ◽

Surface Characterization ◽

High Surface ◽

Surface Characteristics ◽

Post Processing ◽

Stainless Steel 316L ◽

Processing Methods ◽

Particulate Debris

Additive manufacturing of stainless steel is becoming increasingly accessible, allowing for the customisation of structure and surface characteristics; there is little guidance for the post-processing of these metals. We carried out this study to ascertain the effects of various combinations of post-processing methods on the surface of an additively manufactured stainless steel 316L lattice. We also characterized the nature of residual surface particles found after these processes via energy-dispersive X-ray spectroscopy. Finally, we measured the surface roughness of the post-processing lattices via digital microscopy. The native lattices had a predictably high surface roughness from partially molten particles. Sandblasting effectively removed this but damaged the surface, introducing a peel-off layer, as well as leaving surface residue from the glass beads used. The addition of either abrasive polishing or electropolishing removed the peel-off layer but introduced other surface deficiencies making it more susceptible to corrosion. Finally, when electropolishing was performed after the above processes, there was a significant reduction in residual surface particles. The constitution of the particulate debris as well as the lattice surface roughness following each post-processing method varied, with potential implications for clinical use. The work provides a good base for future development of post-processing methods for additively manufactured stainless steel.

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Surface Characterization of an Extruded 6060 Al Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.29-30.67 ◽

2007 ◽

Vol 29-30 ◽

pp. 67-70

Author(s):

Wei Zhang ◽

Jim Metson ◽

C.L. Nguyen ◽

S. Chen

Keyword(s):

Aluminium Alloy ◽

Photoelectron Spectroscopy ◽

Surface Characterization ◽

Extrusion Direction ◽

Surface Characteristics ◽

Al Alloy ◽

X Ray ◽

Film Instability ◽

Mg Content

The surface characteristics of an extruded 6060 aluminium alloy were investigated with X-ray Photoelectron Spectroscopy (XPS). The results revealed that the extruded surface was covered by oxides of aluminium and magnesium. The thickness of aluminium oxide was found to change along the extrusion direction with the thinnest and thickest oxide at the beginning and end of the extrudate, respectively. Magnesium segregation was found on the surface of the extrusion with the highest and lowest Mg concentration at the beginning and end of the extrudate, respectively. This is the inverse result of that expected where increasing Mg content was believed to be associated with film instability and thicker films.

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Characterization of planar Ti:LiNbO3optical waveguides in the visible and near‐infrared spectral range

Journal of Applied Physics ◽

10.1063/1.341764 ◽

1988 ◽

Vol 64 (4) ◽

pp. 1704-1708 ◽

Cited By ~ 3

Author(s):

Fernanda Irrera ◽

Marco Valli

Keyword(s):

Spectral Range ◽

Near Infrared ◽

Infrared Spectral Range ◽

Infrared Spectral

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EDM Surface Characterization of a Ceramic Composite TiB2/SiC

Journal of Engineering Materials and Technology ◽

10.1115/1.2904123 ◽

1991 ◽

Vol 113 (4) ◽

pp. 437-442 ◽

Cited By ~ 17

Author(s):

M. Ramulu ◽

J. L. Garbini

Keyword(s):

Electrical Discharge ◽

Surface Characterization ◽

Ceramic Composite ◽

Surface Characteristics ◽

Power Input ◽

Recast Layer ◽

Electrically Conductive ◽

The Individual ◽

Edm Process

Electrical Discharge Machined (EDM) hole surface characteristics of 20 percent Titanium diboride (TiB2) particulate and Silicon carbide (SiC) matrix composite material were investigated. The EDM hole surfaces produced by using brass, copper and graphite were examined by scanning electron microscopy (SEM) and surface profilometry to determine the surface characteristics. As-machined surfaces showed the microcracks in the recast layer, and the individual TiB2 grains were exposed on the surface. The depth of the recast structure on the surface has varied from 8 μm to less than a micrometer and was approximately proportional to the amount of impinging energy or power input. The EDM process appears to be a promising method of producing an excellent surface in electrically conductive TiB2/SiC composite under slow cutting conditions.

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Effect of Morphology on Spectral Radiative Properties of Three-Dimensionally Ordered Macroporous Ceria Packed Bed

Journal of Heat Transfer ◽

10.1115/1.4024942 ◽

2013 ◽

Vol 135 (12) ◽

Cited By ~ 14

Author(s):

Krithiga Ganesan ◽

Jaona Randrianalisoa ◽

Wojciech Lipiński

Keyword(s):

Spectral Range ◽

Near Infrared ◽

Packed Bed ◽

Radiative Properties ◽

Before And After ◽

Infrared Spectral ◽

Thermochemical Processes ◽

Path Lengths ◽

Ordered Macroporous

In this paper, radiative characterization of a packed bed of novel three-dimensionally ordered macroporous (3DOM) ceria particles is performed in the spectral range relevant to solar thermochemical processes, 0.35–2.2 μm. Normal–hemispherical transmittance and reflectance of three samples of various thicknesses are measured. Monte Carlo ray-tracing (MCRT) and discrete ordinate methods are employed to identify transport scattering albedo and transport extinction coefficient in the spectral range corresponding to weak absorption in the semi-transparency band of ceria. 3DOM ceria particles are characterized by weaker scattering in comparison to sintered ceria ceramics, and increased transparency in the near-infrared spectral range 0.7–2 μm. The ordered pore-morphology of the 3DOM ceria after thermochemical redox cycling between temperatures 1373 K and 1073 K is altered due to sintering of walls of the 3DOM structure. The absorption coefficient of the packed bed is found to be practically independent of morphology. Radiative characterization of 3DOM ceria ceramics before and after thermochemical cycling suggests that preserving the 3DOM structure can lead to scattering characteristics that permit longer attenuation path lengths of incident concentrated solar radiation in the material, as well as be favorable for confinement of the near-infrared radiation during thermochemical cycling leading to favorable thermochemical conditions for fuel production.

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Optics and photonics. Optical materials and components. Characterization of optical materials used in the infrared spectral range from 0,78 μm to 25 μm

10.3403/30192062 ◽

2011 ◽

Keyword(s):

Spectral Range ◽

Optical Materials ◽

Infrared Spectral Range ◽

Infrared Spectral ◽

Materials Used

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Surface Roughness Characterization of ZnO: TiO2-Organic Blended Solar Cells Layers by Atomic Force Microscopy and Fractal Analysis

International Journal of Nanoscience ◽

10.1142/s0219581x14500203 ◽

2014 ◽

Vol 13 (03) ◽

pp. 1450020 ◽

Cited By ~ 6

Author(s):

Ştefan Ţălu ◽

Sebastian Stach ◽

Muhammad Ikram ◽

Dinesh Pathak ◽

Tomas Wagner ◽

...

Keyword(s):

Surface Roughness ◽

Atomic Force Microscopy ◽

Solar Cells ◽

Fractal Analysis ◽

Surface Characterization ◽

Surface Characteristics ◽

Statistical Parameters ◽

Force Microscopy ◽

Atomic Force

The objective of this work is to quantitatively characterize the 3D complexity of ZnO : TiO 2-organic blended solar cells layers by atomic force microscopy and fractal analysis. ZnO : TiO 2-organic blended solar cells layers were investigated by AFM in tapping-mode in air, on square areas of 25 μm2. A detailed methodology for ZnO : TiO 2-organic blended solar cells layers surface fractal characterization, which may be applied for AFM data, is presented. Detailed surface characterization of the surface topography was obtained using statistical parameters, according with ISO 25178-2: 2012. The fractal dimensions Df values (all with average ± standard deviation), obtained with morphological envelopes method, for: blend D1 ( P 3 HT : PCBM : ZnO : TiO 2 blend with ratio 1:0.35:0.175:0.175 mg in 1 ml of Chlorobenzene) is Df = 2.55 ± 0.01; and for blend D2 ( P 3 HT : PCBM : ZnO : TiO 2 blend with ratio 1:0.55:0.075:0.075 mg in 1 ml of Chlorobenzene) is Df = 2.45 ± 0.01. Denoting the ratios in 1 ml of Chlorobenzene with D1 and D2 articles. The 3D surface roughness of samples revealed a fractal structure at nanometer scale. Fractal and AFM analysis may assist manufacturers in developing ZnO : TiO 2-organic blended solar cells layers with better surface characteristics and provides different yet complementary information to that offered by traditional surface statistical parameters.

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