Pub Date : 2024-12-28DOI: 10.1016/j.jqsrt.2024.109333
Randika Dodangodage , Peter F. Bernath , Matthew Wyatt , Chris Boone
Indonesia’s Ruang volcano erupted on April 16, 2024, with subsequent eruptions on April 17 and 30. The resulting plume was observed rising to altitudes of up to 12 km. 10 days after the eruption of the Ruang volcano in April 2024, the Atmospheric Chemistry Experiment (ACE) observed notable increases in SO volume mixing ratios and aerosol extinction at an altitude of approximately 20 km. It was confirmed that the aerosols present were sulfate aerosols from their infrared spectra. The composition and size of the stratospheric sulfate aerosol particles were determined by fitting the infrared transmission spectra. The sulfate aerosols observed in the plume were about 64% (by weight) sulfuric acid, and the droplets had an average median radius of 0.127 m.
{"title":"Atmospheric Chemistry Experiment (ACE) satellite observations of aerosols and SO2 emissions from the 2024 Ruang volcanic eruption","authors":"Randika Dodangodage , Peter F. Bernath , Matthew Wyatt , Chris Boone","doi":"10.1016/j.jqsrt.2024.109333","DOIUrl":"10.1016/j.jqsrt.2024.109333","url":null,"abstract":"<div><div>Indonesia’s Ruang volcano erupted on April 16, 2024, with subsequent eruptions on April 17 and 30. The resulting plume was observed rising to altitudes of up to 12 km. 10 days after the eruption of the Ruang volcano in April 2024, the Atmospheric Chemistry Experiment (ACE) observed notable increases in SO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> volume mixing ratios and aerosol extinction at an altitude of approximately 20 km. It was confirmed that the aerosols present were sulfate aerosols from their infrared spectra. The composition and size of the stratospheric sulfate aerosol particles were determined by fitting the infrared transmission spectra. The sulfate aerosols observed in the plume were about 64% (by weight) sulfuric acid, and the droplets had an average median radius of 0.127 <span><math><mi>μ</mi></math></span>m.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"333 ","pages":"Article 109333"},"PeriodicalIF":2.3,"publicationDate":"2024-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142929288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-28DOI: 10.1016/j.jqsrt.2024.109337
Alexander E. Protasevich, Andrei V. Nikitin
Ro-vibrational energy levels of acetylene isotopologues are reported using variational nuclear motion calculations from empirically optimized full six-dimensional potential energy surface (PES) in the ground electronic state. This surface is based on pure ab initio PES of H12C12CH which took into account the triple, quadruple and quintuple excitations as well as relativistic and diagonal Born-Oppenheimer corrections (DBOC). Variational calculations of the motion of nuclei for all isotopologues were carried out using one exact kinetic energy operator in which only the masses of the atoms were changed. Experimental values of 1529 ro-vibrational levels up to J = 10 of the main isotopologue were used to empirically adjust some 58 lower-order parameters of the PES. The unweighted average RMS for empirically optimized PES is 0.0953 cm−1. Ro-vibrational energy levels of H12C12CH, H13C13CH, D12C12CD, D13C13CD, H12C13CH, H12C12CD, H12C13CD, H13C12CD, D12C13CD up to J = 10 were calculated in the ground electronic state. Calculated ro-vibrational energy levels of H12C12CH, H13C13CH, D12C12CD, H12C13CH, H12C12CD isotopologues were compared with high precision empirical energy levels available in literature.
{"title":"Ro-vibrational levels of acetylene isotopologues calculated from new potential energy surface","authors":"Alexander E. Protasevich, Andrei V. Nikitin","doi":"10.1016/j.jqsrt.2024.109337","DOIUrl":"10.1016/j.jqsrt.2024.109337","url":null,"abstract":"<div><div>Ro-vibrational energy levels of acetylene isotopologues are reported using variational nuclear motion calculations from empirically optimized full six-dimensional potential energy surface (PES) in the ground electronic state. This surface is based on pure ab initio PES of H<sup>12</sup>C<sup>12</sup>CH which took into account the triple, quadruple and quintuple excitations as well as relativistic and diagonal Born-Oppenheimer corrections (DBOC). Variational calculations of the motion of nuclei for all isotopologues were carried out using one exact kinetic energy operator in which only the masses of the atoms were changed. Experimental values of 1529 ro-vibrational levels up to <em>J</em> = 10 of the main isotopologue were used to empirically adjust some 58 lower-order parameters of the PES. The unweighted average RMS for empirically optimized PES is 0.0953 cm<sup>−1</sup>. Ro-vibrational energy levels of H<sup>12</sup>C<sup>12</sup>CH, H<sup>13</sup>C<sup>13</sup>CH, D<sup>12</sup>C<sup>12</sup>CD, D<sup>13</sup>C<sup>13</sup>CD, H<sup>12</sup>C<sup>13</sup>CH, H<sup>12</sup>C<sup>12</sup>CD, H<sup>12</sup>C<sup>13</sup>CD, H<sup>13</sup>C<sup>12</sup>CD, D<sup>12</sup>C<sup>13</sup>CD up to <em>J</em> = 10 were calculated in the ground electronic state. Calculated ro-vibrational energy levels of H<sup>12</sup>C<sup>12</sup>CH, H<sup>13</sup>C<sup>13</sup>CH, D<sup>12</sup>C<sup>12</sup>CD, H<sup>12</sup>C<sup>13</sup>CH, H<sup>12</sup>C<sup>12</sup>CD isotopologues were compared with high precision empirical energy levels available in literature.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"333 ","pages":"Article 109337"},"PeriodicalIF":2.3,"publicationDate":"2024-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142929287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-26DOI: 10.1016/j.jqsrt.2024.109330
Jaromír Petržala, Ladislav Kómar
Remote sensing of nighttime urban light emissions becomes a common part of light pollution modeling. Radiance data gathered by various satellites scanning the Earth surface serve as important inputs for estimating the upward luminous flux of a city, which then allows to evaluate the level of light pollution in its surroundings. The easiest way is to assume the measured radiance of a city pixel as belonging to its direct radiation. However, this radiance is ”contaminated” by scattered radiation coming from the light emitting surroundings of the pixel. In principle, this diffuse light contribution can influence the estimate of the emitted flux. In this paper, we developed a model to assess how important such a contribution can be for cities of different shapes and sizes. The numerical simulations for real city patterns obtained from the VIIRS-DNB database reveal, that scattered radiation could make up on average about 10%–20% of the total upward radiance of a pixel under quite obvious aerosol conditions. We have also derived two simplified models for idealized city patterns which enable relatively simple estimation of the diffuse radiation contribution without the need of complex simulations for realistic cities.
{"title":"The contribution of scattered radiation to the upward radiance of a city","authors":"Jaromír Petržala, Ladislav Kómar","doi":"10.1016/j.jqsrt.2024.109330","DOIUrl":"10.1016/j.jqsrt.2024.109330","url":null,"abstract":"<div><div>Remote sensing of nighttime urban light emissions becomes a common part of light pollution modeling. Radiance data gathered by various satellites scanning the Earth surface serve as important inputs for estimating the upward luminous flux of a city, which then allows to evaluate the level of light pollution in its surroundings. The easiest way is to assume the measured radiance of a city pixel as belonging to its direct radiation. However, this radiance is ”contaminated” by scattered radiation coming from the light emitting surroundings of the pixel. In principle, this diffuse light contribution can influence the estimate of the emitted flux. In this paper, we developed a model to assess how important such a contribution can be for cities of different shapes and sizes. The numerical simulations for real city patterns obtained from the VIIRS-DNB database reveal, that scattered radiation could make up on average about 10%–20% of the total upward radiance of a pixel under quite obvious aerosol conditions. We have also derived two simplified models for idealized city patterns which enable relatively simple estimation of the diffuse radiation contribution without the need of complex simulations for realistic cities.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"333 ","pages":"Article 109330"},"PeriodicalIF":2.3,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142929290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-26DOI: 10.1016/j.jqsrt.2024.109334
Bingqi Yi , Ruiyi Li , Zhiyong Yang
Accurate and reliable knowledge about how clouds with various layers and phases are vertically and horizontally distributed over the globe has been lacking, which hinders the understanding about the impacts of various sub-types of clouds. This study utilizes the cloud retrieval products from the CloudSat/CALIPSO satellite observations from 2007 to 2010 to analyze the global distributions of multi-layer and multi-phase clouds as well as their cloud radiative effects (CRE) at the top of the atmosphere (TOA), at the surface, and within the atmosphere. We separate and aggregate cloudy satellite footprints by the number of cloud layers, and further consider the different combinations of cloud phases for the one-layer and multi-layer clouds. The globally averaged total cloud fraction is 72.52 %, with the one-layer and multi-layer clouds take up 49.39 % and 23.13 %, respectively. The one-layer water, ice, and mixed-phase cloud fractions are 21.93 %, 19.42 %, and 8.04 %, respectively. The two-layer and three-layer clouds most frequently occur with one ice layer at the top. The heights of cloud top and bottom as well as the cloud thickness are correspondingly derived for all sub-types of clouds. The globally averaged TOA net total CRE is −18.25 W m−2, with −14.63 W m−2 attributed to one-layer clouds and −3.62 W m−2 to multi-layer clouds. At the surface, the global annual average net total CRE is −25.01 W m−2, and the one-layer and multi-layer clouds contribute −17.24 W m−2 and −7.77 W m−2, respectively. Clouds generally exert a net heating effect within the atmosphere. Our findings provide valuable insights into the detailed layer and phase structures of clouds and could serve as the reference for evaluating cloud structure and radiation simulations.
关于具有不同层和阶段的云如何在全球垂直和水平分布的准确和可靠的知识一直缺乏，这阻碍了对各种子类型云的影响的理解。本研究利用2007 - 2010年CloudSat/CALIPSO卫星观测资料的云检索产品，分析了多层多相云的全球分布及其在大气顶部、地面和大气内部的云辐射效应（CRE）。我们根据云层的层数对卫星云足迹进行了分离和汇总，并进一步考虑了单层云和多层云的不同云相组合。全球平均总云量为72.52%，其中单层云量占49.39%，多层云量占23.13%。单层水、冰和混合相云组分分别为21.93%、19.42%和8.04%。两层和三层云最常见的情况是顶部有一层冰。各子类型云的云顶、云底高度和云厚相应得到。全球平均TOA净总CRE为−18.25 W m−2，其中−14.63 W m−2来自单层云，−3.62 W m−2来自多层云。在地表，全球年平均净总CRE为−25.01 W m−2，其中单层云和多层云分别贡献了−17.24 W m−2和−7.77 W m−2。云通常在大气中产生净加热效应。我们的发现提供了对云的详细层和相结构的有价值的见解，可以作为评估云结构和辐射模拟的参考。
{"title":"Global distributions of multi-layer and multi-phase clouds and their cloud radiative effects","authors":"Bingqi Yi , Ruiyi Li , Zhiyong Yang","doi":"10.1016/j.jqsrt.2024.109334","DOIUrl":"10.1016/j.jqsrt.2024.109334","url":null,"abstract":"<div><div>Accurate and reliable knowledge about how clouds with various layers and phases are vertically and horizontally distributed over the globe has been lacking, which hinders the understanding about the impacts of various sub-types of clouds. This study utilizes the cloud retrieval products from the CloudSat/CALIPSO satellite observations from 2007 to 2010 to analyze the global distributions of multi-layer and multi-phase clouds as well as their cloud radiative effects (CRE) at the top of the atmosphere (TOA), at the surface, and within the atmosphere. We separate and aggregate cloudy satellite footprints by the number of cloud layers, and further consider the different combinations of cloud phases for the one-layer and multi-layer clouds. The globally averaged total cloud fraction is 72.52 %, with the one-layer and multi-layer clouds take up 49.39 % and 23.13 %, respectively. The one-layer water, ice, and mixed-phase cloud fractions are 21.93 %, 19.42 %, and 8.04 %, respectively. The two-layer and three-layer clouds most frequently occur with one ice layer at the top. The heights of cloud top and bottom as well as the cloud thickness are correspondingly derived for all sub-types of clouds. The globally averaged TOA net total CRE is −18.25 W m<sup>−2</sup>, with −14.63 W m<sup>−2</sup> attributed to one-layer clouds and −3.62 W m<sup>−2</sup> to multi-layer clouds. At the surface, the global annual average net total CRE is −25.01 W m<sup>−2</sup>, and the one-layer and multi-layer clouds contribute −17.24 W m<sup>−2</sup> and −7.77 W m<sup>−2</sup>, respectively. Clouds generally exert a net heating effect within the atmosphere. Our findings provide valuable insights into the detailed layer and phase structures of clouds and could serve as the reference for evaluating cloud structure and radiation simulations.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"333 ","pages":"Article 109334"},"PeriodicalIF":2.3,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142889185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-25DOI: 10.1016/j.jqsrt.2024.109335
Tianrui Bai , Lynette Edline Momo Jeulefack , Songfeng Li , Jie Cheng , Shuidong Dai , Linhua Liu , Fei Li
Photodissociation of AlO may be important for the aluminium chemistry in various astrophysical regions. The photodissociation cross sections and rates of AlO were investigated over the temperature range from 0 to 15000 K in this work. Firstly, the state-resolved cross sections at the wavelength of 50 − 5000 nm for transitions from the ground and first excited states were calculated using ab initio potential energy curves and transition dipole moments. The temperature-dependent cross sections were then obtained by assuming a Boltzmann distribution to describe the population of the initial state. Several common radiation fields (interstellar, solar and blackbody radiation field) were selected as the radiation fields, and then the photodissociation rates in different radiation fields were obtained. The photodissociation rates in all studied radiation fields exhibit a positive correlation with increasing temperature. This finding indicates that the total photodissociation rates are sensitive to the temperature. In addition, the photodissociation rates in the solar radiation field are higher than those in the interstellar radiation fields, indicating that photodissociation rate is associated with the type of radiation field in which the molecule is exposed. The calculated photodissociation cross sections and rates of AlO are useful to investigate the chemical evolution of the aluminum element in the interstellar environment.
{"title":"Absorption spectroscopy of AlO including photodissociation","authors":"Tianrui Bai , Lynette Edline Momo Jeulefack , Songfeng Li , Jie Cheng , Shuidong Dai , Linhua Liu , Fei Li","doi":"10.1016/j.jqsrt.2024.109335","DOIUrl":"10.1016/j.jqsrt.2024.109335","url":null,"abstract":"<div><div>Photodissociation of AlO may be important for the aluminium chemistry in various astrophysical regions. The photodissociation cross sections and rates of AlO were investigated over the temperature range from 0 to 15000 K in this work. Firstly, the state-resolved cross sections at the wavelength of 50 − 5000 nm for transitions from the ground and first excited states were calculated using <em>ab initio</em> potential energy curves and transition dipole moments. The temperature-dependent cross sections were then obtained by assuming a Boltzmann distribution to describe the population of the initial state. Several common radiation fields (interstellar, solar and blackbody radiation field) were selected as the radiation fields, and then the photodissociation rates in different radiation fields were obtained. The photodissociation rates in all studied radiation fields exhibit a positive correlation with increasing temperature. This finding indicates that the total photodissociation rates are sensitive to the temperature. In addition, the photodissociation rates in the solar radiation field are higher than those in the interstellar radiation fields, indicating that photodissociation rate is associated with the type of radiation field in which the molecule is exposed. The calculated photodissociation cross sections and rates of AlO are useful to investigate the chemical evolution of the aluminum element in the interstellar environment.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"333 ","pages":"Article 109335"},"PeriodicalIF":2.3,"publicationDate":"2024-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142929291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-24DOI: 10.1016/j.jqsrt.2024.109322
Louis Rihouey, Philippe Ben-Abdallah, Riccardo Messina
We introduce a theoretical framework to describe the heat flux radiated in the near-field regime by a set of magneto-optical thermal nanoemitters close to a substrate in the presence of an external magnetic field. Then, we investigate the particular case of a single emitter and we demonstrate that the external field can induce both an amplification of the heat exchanged between emittter and substrate and a focusing of the Poynting field at the substrate interface at deep sub-wavelength scale. These effects open up promising perspectives for the development of heat-assisted magnetic-recording technology.
{"title":"Deep sub-wavelength scale focusing of heat flux radiated by magneto-optical nanoemitters in the presence of an external magnetic-field","authors":"Louis Rihouey, Philippe Ben-Abdallah, Riccardo Messina","doi":"10.1016/j.jqsrt.2024.109322","DOIUrl":"10.1016/j.jqsrt.2024.109322","url":null,"abstract":"<div><div>We introduce a theoretical framework to describe the heat flux radiated in the near-field regime by a set of magneto-optical thermal nanoemitters close to a substrate in the presence of an external magnetic field. Then, we investigate the particular case of a single emitter and we demonstrate that the external field can induce both an amplification of the heat exchanged between emittter and substrate and a focusing of the Poynting field at the substrate interface at deep sub-wavelength scale. These effects open up promising perspectives for the development of heat-assisted magnetic-recording technology.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"333 ","pages":"Article 109322"},"PeriodicalIF":2.3,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142929293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-24DOI: 10.1016/j.jqsrt.2024.109324
Robert J. Hargreaves , Iouli E. Gordon , Xinchuan Huang , Geoffrey C. Toon , Laurence S. Rothman
An updated carbon dioxide line list for the HITEMP spectroscopic database is presented. This line list covers the 0–17 697 cm−1 (565 nm) spectral range and is built upon the AI-3000K semi-empirical line list for 12C16O2, 13C16O2, 16O12C18O, and 16O12C17O (Huang et al., 2023), combined with HITRAN2020 data, additional isotopologues, and further improvements described in this work. In order to make the line list practical for applications, over 36 billion individual transitions of the original AI-3000K line list have been separated into “strong” and “weak”. “Strong” transitions were adapted directly, while the weak transitions were then combined into so-called “effective” lines. The latter can accurately account for the intensity contribution of underlying weak AI-3000K transitions while reducing the database by over two orders of magnitude (to 326 million). In addition, pressure broadening parameters have been revised for this work to improve applicability at high temperatures. The line list has been added to HITEMP and is suitable for modeling the spectrum of carbon dioxide at temperatures up to 3000 K.
Multiple validations have been carried out against terrestrial CO2 retrievals, as well as high-resolution experimental measurements of CO2 at different temperatures (up to 2000 K). The updated HITEMP line list includes 12 isotopologues of CO2 and is provided in the standard HITRAN/HITEMP format, which is accepted by many community tools. It is demonstrated to be practical, accurate, and sufficiently complete for high-temperature environments. This work will be suitable for various high-temperature spectroscopic applications including exoplanet retrievals and remote sensing of combustion environments.
提出了HITEMP光谱数据库中最新的二氧化碳谱线表。该谱线列表涵盖0-17697 cm−1 （>565 nm）光谱范围，基于AI-3000K 12C16O2、13C16O2、16O12C18O和16O12C17O的半经验谱线列表（Huang et al., 2023），结合HITRAN2020数据、额外的同位素以及本工作中描述的进一步改进。为了使线路列表在实际应用中更加实用，原始AI-3000K线路列表中超过360亿个单独的过渡被分为“强”和“弱”。“强”的过渡被直接改编，而弱的过渡则被组合成所谓的“有效”的线条。后者可以准确地解释潜在的弱AI-3000K转换的强度贡献，同时将数据库减少两个数量级以上（至~ 3.26亿）。此外，还对压力展宽参数进行了修订，以提高在高温下的适用性。该线列表已添加到HITEMP，适用于模拟温度高达3000k的二氧化碳光谱。
{"title":"Updating the carbon dioxide line list in HITEMP","authors":"Robert J. Hargreaves , Iouli E. Gordon , Xinchuan Huang , Geoffrey C. Toon , Laurence S. Rothman","doi":"10.1016/j.jqsrt.2024.109324","DOIUrl":"10.1016/j.jqsrt.2024.109324","url":null,"abstract":"<div><div>An updated carbon dioxide line list for the HITEMP spectroscopic database is presented. This line list covers the 0–17<!--> <!-->697 cm<sup>−1</sup> (<span><math><mo>></mo></math></span>565 nm) spectral range and is built upon the AI-3000K semi-empirical line list for <sup>12</sup>C<sup>16</sup>O<sub>2</sub>, <sup>13</sup>C<sup>16</sup>O<sub>2</sub>, <sup>16</sup>O<sup>12</sup>C<sup>18</sup>O, and <sup>16</sup>O<sup>12</sup>C<sup>17</sup>O (Huang et al., 2023), combined with HITRAN2020 data, additional isotopologues, and further improvements described in this work. In order to make the line list practical for applications, over 36 billion individual transitions of the original AI-3000K line list have been separated into “strong” and “weak”. “Strong” transitions were adapted directly, while the weak transitions were then combined into so-called “effective” lines. The latter can accurately account for the intensity contribution of underlying weak AI-3000K transitions while reducing the database by over two orders of magnitude (to <span><math><mo>∼</mo></math></span>326 million). In addition, pressure broadening parameters have been revised for this work to improve applicability at high temperatures. The line list has been added to HITEMP and is suitable for modeling the spectrum of carbon dioxide at temperatures up to 3000 K.</div><div>Multiple validations have been carried out against terrestrial CO<sub>2</sub> retrievals, as well as high-resolution experimental measurements of CO<sub>2</sub> at different temperatures (up to 2000 K). The updated HITEMP line list includes 12 isotopologues of CO<sub>2</sub> and is provided in the standard HITRAN/HITEMP format, which is accepted by many community tools. It is demonstrated to be practical, accurate, and sufficiently complete for high-temperature environments. This work will be suitable for various high-temperature spectroscopic applications including exoplanet retrievals and remote sensing of combustion environments.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"333 ","pages":"Article 109324"},"PeriodicalIF":2.3,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142929292","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-22DOI: 10.1016/j.jqsrt.2024.109327
Tatiana Zhuravleva
The results of statistical modeling of the angular characteristics of reflected solar radiation in the atmosphere containing a layer of ice crystal clouds with anisotropy caused by the orientation of particles in space are presented. Numerical experiments are carried out using (1) original algorithm of the Monte Carlo method for calculating characteristics of unpolarized solar radiation taking into account the multiple scattering, reflection from the underlying surface, and attenuation by aerosol particles and due to molecular scattering and (2) optical model of anisotropic medium, composed of horizontally oriented hexagonal plates or Parry columns (visible range), developed previously in Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences, Tomsk, Russia. We discuss the patterns of formation of reflected solar radiation without taking into account the aerosol-molecular component of the atmosphere and surface reflection; these simulation results make it possible to identify the specific features of radiative transfer, caused exclusively by the effects of anisotropy of ice-crystal clouds. The factors that determine the influence of the surface reflection and aerosol attenuation on halo phenomena are described. It is shown that, as the surface albedo increases, the near-isotropic radiation field is formed outside the main halo lines and the intensity of different halo lines decreases down to the level when these lines or their components become almost invisible against the background of the contribution formed by surface-reflected radiation. Our radiation code is to be used for a research into the optical phenomena, observed from the Earth's surface and space, and, in particular, for an additional study of scattering by oriented ice crystals near the specular reflection direction (solar glint).
{"title":"Statistical simulation of the angular distribution of reflected solar radiation in optically anisotropic ice-crystal clouds: Horizontally oriented particles","authors":"Tatiana Zhuravleva","doi":"10.1016/j.jqsrt.2024.109327","DOIUrl":"10.1016/j.jqsrt.2024.109327","url":null,"abstract":"<div><div>The results of statistical modeling of the angular characteristics of reflected solar radiation in the atmosphere containing a layer of ice crystal clouds with anisotropy caused by the orientation of particles in space are presented. Numerical experiments are carried out using (1) original algorithm of the Monte Carlo method for calculating characteristics of unpolarized solar radiation taking into account the multiple scattering, reflection from the underlying surface, and attenuation by aerosol particles and due to molecular scattering and (2) optical model of anisotropic medium, composed of horizontally oriented hexagonal plates or Parry columns (visible range), developed previously in Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences, Tomsk, Russia. We discuss the patterns of formation of reflected solar radiation without taking into account the aerosol-molecular component of the atmosphere and surface reflection; these simulation results make it possible to identify the specific features of radiative transfer, caused exclusively by the effects of anisotropy of ice-crystal clouds. The factors that determine the influence of the surface reflection and aerosol attenuation on halo phenomena are described. It is shown that, as the surface albedo increases, the near-isotropic radiation field is formed outside the main halo lines and the intensity of different halo lines decreases down to the level when these lines or their components become almost invisible against the background of the contribution formed by surface-reflected radiation. Our radiation code is to be used for a research into the optical phenomena, observed from the Earth's surface and space, and, in particular, for an additional study of scattering by oriented ice crystals near the specular reflection direction (solar glint).</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"333 ","pages":"Article 109327"},"PeriodicalIF":2.3,"publicationDate":"2024-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142889186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Black carbon (BC) is a type of light absorbing substances in atmosphere, which has a significant impact on regional and global radiation balance. When evaluating the climatic effects of BC, the complex morphology of BC poses a challenge for large-scale climate models to proceed with the calculations. In this study, we developed a deep convolutional neural network (CNN) that combines residual links with one-dimensional multi-scale dilated convolutions. Using the multiple sphere T-matrix (MSTM), the extinction efficiency (Qext), absorption efficiency (Qabs), scattering efficiency (Qsca), and asymmetry factor (g) for coated BC were evaluated under different fractal dimensions, monomer radii, refractive indices, and incident wavelengths, by considering the volume fraction of thinly coated BC and thickly coated BC in the range from 20 % to 60 % and 2 % to 10 %, respectively. The optical properties of small particles were then treated as the training set to train the CNN, and the trained CNN was used to output the optical properties of large particles. By comparing the Qext, Qabs, Qsca, and g predicted by the CNN with those obtained from the MSTM, we found that the CNN has superior predictive capabilities for the optical properties of coated BC, and the newly established CNN exhibited broad applicability in predicting the optical properties of coated BC. Although relative deviations are observed in predicting the optical properties of small particles using the CNN, the errors for large particle predictions are essentially <1 %, with the mean absolute errors and root mean square errors being lower than 0.029 and 0.043, respectively. This study demonstrates that the CNN has great potential for further development. Future research should focus on how to use less data to predict more accurate results for the range of computational parameters for BC.
{"title":"Using convolutional neural networks to predict the optical properties of coated black carbon","authors":"Zhenhai Qin, Jinhong Wu, Haihui Wang, Yongming Zhang, Qixing Zhang","doi":"10.1016/j.jqsrt.2024.109326","DOIUrl":"10.1016/j.jqsrt.2024.109326","url":null,"abstract":"<div><div>Black carbon (BC) is a type of light absorbing substances in atmosphere, which has a significant impact on regional and global radiation balance. When evaluating the climatic effects of BC, the complex morphology of BC poses a challenge for large-scale climate models to proceed with the calculations. In this study, we developed a deep convolutional neural network (CNN) that combines residual links with one-dimensional multi-scale dilated convolutions. Using the multiple sphere T-matrix (MSTM), the extinction efficiency (<em>Q<sub>ext</sub></em>), absorption efficiency (<em>Q<sub>abs</sub></em>), scattering efficiency (<em>Q<sub>sca</sub></em>), and asymmetry factor (<em>g</em>) for coated BC were evaluated under different fractal dimensions, monomer radii, refractive indices, and incident wavelengths, by considering the volume fraction of thinly coated BC and thickly coated BC in the range from 20 % to 60 % and 2 % to 10 %, respectively. The optical properties of small particles were then treated as the training set to train the CNN, and the trained CNN was used to output the optical properties of large particles. By comparing the <em>Q<sub>ext</sub>, Q<sub>abs</sub>, Q<sub>sca</sub></em>, and <em>g</em> predicted by the CNN with those obtained from the MSTM, we found that the CNN has superior predictive capabilities for the optical properties of coated BC, and the newly established CNN exhibited broad applicability in predicting the optical properties of coated BC. Although relative deviations are observed in predicting the optical properties of small particles using the CNN, the errors for large particle predictions are essentially <1 %, with the mean absolute errors and root mean square errors being lower than 0.029 and 0.043, respectively. This study demonstrates that the CNN has great potential for further development. Future research should focus on how to use less data to predict more accurate results for the range of computational parameters for BC.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"333 ","pages":"Article 109326"},"PeriodicalIF":2.3,"publicationDate":"2024-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142889188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The optical properties of oceanic foam are crucial for satellite remote sensing inversion and target identification, with the volume scattering properties of foam layers significantly influencing the directionality of light scattering, making them a focal point in sea surface scattering research. To achieve efficient computation and analysis of the volume scattering properties of foam layers, this paper establishes a large-scale foam aggregate light scattering model based on geometric optics theory. An efficient algorithm for the foam volume scattering phase function was developed using GPU acceleration, and its convergence and acceleration performance were analyzed and evaluated. Furthermore, the influences of various factors, including different fractal models, particle numbers, random orientations of fractal structures, and asymmetric geometries, on the average volume scattering properties of the foam multi-spherical aggregates were analyzed. The results indicate that the influences of the fractal structures, particle numbers, and orientations of fractal structures on the average scattering properties is minimal, with correlation coefficients exceeding 0.99. This study provides an efficient algorithm for obtaining the average volume scattering phase function of foam, offering strong support for further research on sea surface scattering characteristics involving foam layers.
{"title":"An effective computational method and analysis of scattering characteristics for sea surface foam layer","authors":"Yue Zhang , Xiaoxiao Yu , Peng Gao , Chunlin Huang , Qixiang Chen , Yuan Yuan , Shikui Dong , Kaifeng Lin","doi":"10.1016/j.jqsrt.2024.109332","DOIUrl":"10.1016/j.jqsrt.2024.109332","url":null,"abstract":"<div><div>The optical properties of oceanic foam are crucial for satellite remote sensing inversion and target identification, with the volume scattering properties of foam layers significantly influencing the directionality of light scattering, making them a focal point in sea surface scattering research. To achieve efficient computation and analysis of the volume scattering properties of foam layers, this paper establishes a large-scale foam aggregate light scattering model based on geometric optics theory. An efficient algorithm for the foam volume scattering phase function was developed using GPU acceleration, and its convergence and acceleration performance were analyzed and evaluated. Furthermore, the influences of various factors, including different fractal models, particle numbers, random orientations of fractal structures, and asymmetric geometries, on the average volume scattering properties of the foam multi-spherical aggregates were analyzed. The results indicate that the influences of the fractal structures, particle numbers, and orientations of fractal structures on the average scattering properties is minimal, with correlation coefficients exceeding 0.99. This study provides an efficient algorithm for obtaining the average volume scattering phase function of foam, offering strong support for further research on sea surface scattering characteristics involving foam layers.</div></div>","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"333 ","pages":"Article 109332"},"PeriodicalIF":2.3,"publicationDate":"2024-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142889190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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