scholarly journals A method of measuring transmittance of radiation from the film of ice 0 in the IR wave band deposited on a dielectric plate

2022 ◽  
Vol 962 (1) ◽  
pp. 012027
Author(s):  
A O Orlov ◽  
A A Gurulev ◽  
S V Tsyrenzhapov
Keyword(s):  
Water Vapor ◽  
Halogen Lamp ◽  
Wave Band ◽  
Spectral Measurements ◽  
Ir Radiation ◽  
First Case ◽  
Nitrogen Vapor ◽  
Probing Signal ◽  
Intense Signal ◽  
Heated Glass

Abstract A method of measuring transmittance of radiation from the film of ice 0 in the infrared wave band is described. Ice 0 is formed from supercooled water at the temperature below –23°C. This ice is ferroelectric and forms a highly conductive layer of the nanometric order of thickness at the boundary with dielectric. The complexity of the experiment consisted in the necessity of using low intensities of the probing signal and considering radiation of the cooled parts of the installation. In order to obtain a thin film of ice, the method of depositing water vapor on a substrate cooled in nitrogen was used. The method rules out formation of condensate in cooling. Deposition of water vapor is possible only in heating, when delivery of cold nitrogen vapor into the chamber with the sample is excluded. To ensure exposure of the film to IR radiation, two sources of infrared radiation were considered: a halogen lamp with a broad radiation spectrum (on the surface of heated glass) and a CO2 laser with the radiation wavelength of 10.6 µm. In the first case, spectral measurements are possible when filters are used. In the installation based on a CO2 laser, an intense signal is emitted, requiring consideration of sample heating. Components of the installation have been elaborated and investigated, on which transmittance of radiation from the film of ice 0 is planned to be measured.

scholarly journals Water Vapor Retrieval using the Precision Solar Spectroradiometer

2017 ◽  
Author(s):  
Panagiotis-Ioannis Raptis ◽  
Stelios Kazadzis ◽  
Julian Gröbner ◽  
Natalia Kouremeti ◽  
Lionel Doppler ◽  
...  
Keyword(s):  
Water Vapor ◽  
Single Channel ◽  
Microwave Radiometer ◽  
Coefficient Of Determination ◽  
High Temporal Resolution ◽  
Spectral Approach ◽  
Spectral Measurements ◽  
Channel Wavelength ◽  
Relative Differences ◽  
High Absorption

Abstract. The Precision Solar SpectroRadiometer (PSR) is a new spectroradiometer developed at Physikalisch-Meteorologisches Observatorium Davos-World Radiation Center (PMOD-WRC), Davos, measuring Direct Solar Irradiance at the surface, in the 300–1020 nm spectral range at high temporal resolution. The purpose of this work is to investigate the instrument's potential of retrieving Integrated Water Vapor (IWV) using its spectral measurements. Two different approaches were developed in order to retrieve IWV, the first one using single channel/wavelength measurements, following a theoretical water vapor high absorption wavelength, and the second one using direct sun irradiance integrated at a certain spectral region. IWV results have been validated using a 2-year dataset, consisting of an AERONET sun- photometer Cimel CE318, a Global Positioning System (GPS), a Microwave Radiometer Profiler (MWP) and radiosonde retrievals recorded at Meteorological Observatorium Lindenberg, Germany. For the monochromatic approach, better agreement with retrievals from other methods/instruments was achieved using the 946 nm channel, while for the spectral approach using the 934–948 nm window. Compared to other instruments' retrievals, the monochromatic approach leads to mean relative differences up to 3.3 % with the coefficient of determination (R2) being in the region of 0.87–0.95, while for the spectral approach mean relative differences up to 0.7 % were recorded with R2 in the region of 0.96–0.98. Uncertainties related to IWV retrieval methods were investigated and found to be less than 0.28 cm for both methods. Absolute IWV deviations of differences between PSR and other instruments were determined the range of 0.08–0.30 cm and only in extreme cases would reach up to 15 %.

Emissivity Measurement of Semitransparent Textiles

2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
P. Bison ◽  
A. Bortolin ◽  
G. Cadelano ◽  
G. Ferrarini ◽  
E. Grinzato
Keyword(s):  
Carbon Powder ◽  
Wave Band ◽  
Ir Radiation ◽  
Long Wave ◽  
Emissivity Measurement ◽  
Normal Procedure ◽  
Production Industry

In the textiles production industry it is more and more common to advertise new textiles, especially for sportswear, by claiming their ability to emit IR radiation in the long wave band at a higher degree with respect to normal clothes, that is highly beneficial to improve sporting performances. Three textiles are compared, one normal and two “special,” with Ag+ ions and carbon powder added, with different colors. The emissivity of the textiles has been measured to determine if it is increased in the “special” textiles with respect to the normal one. No substantial increase has been noticed. Nonetheless, the test implied some nonstandard procedures due to the semitransparent nature of the textiles, in comparison with the normal procedure that is commonly used on opaque surfaces.

scholarly journals Far-Infrared Radiative Properties of Water Vapor and Clouds in Antarctica

2015 ◽  
Vol 96 (9) ◽  
pp. 1505-1518 ◽  
Author(s):  
Luca Palchetti ◽  
Giovanni Bianchini ◽  
Gianluca Di Natale ◽  
Massimo Del Guasta
Keyword(s):  
Water Vapor ◽  
Spectral Region ◽  
Thermal Emission ◽  
Far Infrared ◽  
Radiative Properties ◽  
Spectral Measurements ◽  
Sky Conditions ◽  
Stratospheric Clouds ◽  
The Antarctic ◽  
Lidar Observations

Abstract Water vapor and clouds are among the most important greenhouse components whose radiative features cover all the broad spectral range of the thermal emission of the atmosphere. Typically more than 40% of the total thermal emission of Earth occurs in the far-infrared (FIR) spectral region from 100 to 667 cm−1 (wavelengths from 100 to 15 µm). Nevertheless, this spectral region has not ever been fully covered down to 100 cm−1 by space missions, and only a few ground-based experiments exist because of the difficulty of performing measurements from high altitude and very dry locations where the atmosphere is sufficiently transparent to observe the FIR emission features. To cover this lack of observations, the Italian experiment “Radiative Properties of Water Vapor and Clouds in Antarctica” has collected a 2-yr dataset of spectral measurements of the radiance emitted by the atmosphere and by clouds, such as cirrus and polar stratospheric clouds, from 100 to 1,400 cm−1 (100–7 µm of wavelength), including the underexplored FIR region, along with polarization-sensitive lidar observations, daily radiosondes, and other ancillary information to characterize the atmosphere above the site. Measurements have been performed almost continuously with a duty cycle of 6 out of 9 h, from the Italian–French base of Concordia at Dome C over the Antarctic Plateau at 3,230 m MSL, in all-sky conditions since 2012. Because of the uniqueness of the observations, this dataset will be extremely valuable for evaluating the accuracy of atmospheric absorption models (both gas and clouds) in the underexplored FIR and to detect possible daily, seasonal, and annual climate signatures.

Influence of the interference between water vapor lines on the atmospheric transmission of near-IR radiation

2008 ◽  
Vol 104 (2) ◽  
pp. 165-171 ◽  
Author(s):  
A. D. Bykov ◽  
N. N. Lavrent’eva ◽  
T. P. Mishina ◽  
L. N. Sinitsa
Keyword(s):  
Water Vapor ◽  
Atmospheric Transmission ◽  
Ir Radiation ◽  
Near Ir

Absorption of IR radiation by water vapor and carbon dioxide in solar greenhouses

2009 ◽  
Vol 45 (4) ◽  
pp. 274-275
Author(s):  
A. G. Khalimov ◽  
B. E. Khairiddinov ◽  
V. D. Kim ◽  
G. G. Khalimov
Keyword(s):  
Carbon Dioxide ◽  
Water Vapor ◽  
Ir Radiation

scholarly journals Improvement in cloud retrievals from VIIRS through the use of infrared absorption channels constructed from VIIRS-CrIS data fusion

2020 ◽  
Author(s):  
Yue Li ◽  
Bryan A. Baum ◽  
Andrew K. Heidinger ◽  
W. Paul Menzel ◽  
Elisabeth Weisz
Keyword(s):  
Water Vapor ◽  
Spatial Resolution ◽  
Ir Absorption ◽  
Polar Regions ◽  
Co2 Absorption ◽  
Spectral Measurements ◽  
Ice Cloud ◽  
Cloud Properties ◽  
Cloud Mask ◽  
Thermodynamic Phase

Abstract. Retrieval of semitransparent ice cloud properties from the Visible Infrared Imaging Radiometer Suite (VIIRS) satellite sensor on the Suomi-NPP and NOAA-20 platforms is challenging due to the absence of infrared (IR) water vapor and CO2 absorption channels. However, on these platforms, there is a companion sensor called the Crosstrack Infrared Sounder (CrIS) that provides these spectral measurements, but at a lower spatial resolution (~ 15 km at nadir). To mitigate the lack of VIIRS spectral measurements in these IR absorption channels, recent studies suggest an approach to supplement VIIRS measurements by fusion of the imager and sounder data. In particular, Weisz et al. (2017) demonstrate a method to construct IR water vapor and CO2 absorption channel radiances for VIIRS at 750 m spatial resolution. Based on these constructed channels for both Suomi-NPP and NOAA-20, this study evaluates three cloud properties – cloud mask, cloud thermodynamic phase, and cloud top height – through comparison to the CALIPSO/CALIOP V4-20 cloud layer products and MODIS Collection 6.1 cloud top products. Each of these cloud properties show improvement with the use of these constructed channel radiances. The major improvement for the cloud mask is found over polar regions, where the correct cloud detection percentage increases due to decrease in missed cloud and/or false detection. For cloud thermodynamic phase, the ice cloud fraction increases over non-polar regions and the combined liquid water and ice cloud discrimination improves in comparison with CALIPSO. The retrieved cloud top height for semitransparent ice clouds increases over non-polar regions and tends to be closer to the true CALIPSO/CALIOP cloud top height. Moreover, the uncertainty of cloud top height retrievals decreases globally for these clouds.

scholarly journals Effect of Humidity on CO2/N2 and CO2/CH4 Separation Using Novel Robust Mixed Matrix Composite Hollow Fiber Membranes: Experimental and Model Evaluation

Membranes ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 6 ◽  
Author(s):  
Clara Casado-Coterillo ◽  
Ana Fernández-Barquín ◽  
Angel Irabien
Keyword(s):  
Water Vapor ◽  
Relative Humidity ◽  
Matrix Composite ◽  
Hollow Fiber ◽  
Co2 Concentration ◽  
Effect Of Temperature ◽  
Mixed Matrix ◽  
Mixed Gas ◽  
Selective Layer ◽  
First Case

In this work, the performance of new robust mixed matrix composite hollow fiber (MMCHF) membranes with a different selective layer composition is evaluated in the absence and presence of water vapor in CO2/N2 and CO2/CH4 separation. The selective layer of these membranes is made of highly permeable hydrophobic poly(trimethyl-1-silylpropine) (PTMSP) and hydrophilic chitosan-ionic liquid (IL-CS) hybrid matrices, respectively, filled with hydrophilic zeolite 4A particles in the first case and HKUST-1 nanoparticles in the second, coated over compatible supports. The effect of water vapor in the feed or using a commercial hydrophobic PDMSXA-10 HF membrane has also been studied for comparison. Mixed gas separation experiments were performed at values of 0 and 50% relative humidity (RH) in the feed and varying CO2 concentration in N2 and CH4, respectively. The performance has been validated by a simple mathematical model considering the effect of temperature and relative humidity on membrane permeability.

scholarly journals Improvement in cloud retrievals from VIIRS through the use of infrared absorption channels constructed from VIIRS+CrIS data fusion

2020 ◽  
Vol 13 (7) ◽  
pp. 4035-4049
Author(s):  
Yue Li ◽  
Bryan A. Baum ◽  
Andrew K. Heidinger ◽  
W. Paul Menzel ◽  
Elisabeth Weisz
Keyword(s):  
Water Vapor ◽  
Spatial Resolution ◽  
Ir Absorption ◽  
Polar Regions ◽  
Co2 Absorption ◽  
Spectral Measurements ◽  
Ice Cloud ◽  
Cloud Properties ◽  
Cloud Mask ◽  
Thermodynamic Phase

Abstract. Retrieval of semitransparent ice cloud properties from the Visible Infrared Imaging Radiometer Suite (VIIRS) satellite sensor on the Suomi National Polar-orbiting Partnership (S-NPP) and NOAA-20 platforms is challenging due to the absence of infrared (IR) water vapor and CO2 absorption channels. However, on these platforms, there is a companion sensor called the Crosstrack Infrared Sounder (CrIS) that provides these spectral measurements but at a lower spatial resolution (∼15 km at nadir). To mitigate the lack of VIIRS spectral measurements in these IR absorption channels, recent studies suggest an approach to supplement VIIRS measurements by fusion of the imager and sounder data. In particular, Weisz et al. (2017) demonstrate a method to construct IR water vapor and CO2 absorption channel radiances for VIIRS at 750 m spatial resolution. Based on these constructed channels for both S-NPP and NOAA-20, this study evaluates three cloud properties – cloud mask, cloud thermodynamic phase, and cloud top height – through comparison to the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation/Cloud-Aerosol Lidar with Orthogonal Polarization (CALIPSO/CALIOP) V4-20 cloud layer products and Moderate Resolution Imaging Spectroradiometer (MODIS) Collection 6.1 cloud top products. Each of these cloud properties shows improvement with the use of these constructed channel radiances. The major improvement for the cloud mask is found over polar regions, where the correct cloud detection percentage increases due to a decrease in missed clouds and/or false detection. For cloud thermodynamic phase, the ice cloud fraction increases over non-polar regions and the combined liquid water and ice cloud discrimination improves in comparison with CALIPSO. The retrieved cloud top height for semitransparent ice clouds increases over non-polar regions and tends to be closer to the true CALIPSO/CALIOP cloud top height. Moreover, the uncertainty of cloud top height retrievals decreases globally for these clouds.

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