Article
Environmental Sciences
Felix Ploeger, Mohamadou Diallo, Edward Charlesworth, Paul Konopka, Bernard Legras, Johannes C. Laube, Jens-Uwe Grooss, Gebhard Guenther, Andreas Engel, Martin Riese
Summary: This study investigates the global stratospheric Brewer-Dobson circulation (BDC) using ERA5 meteorological reanalysis data, finding a slower BDC compared to ERA-Interim. Age trends in ERA5 show a negative trend throughout the stratosphere, but with step-like fluctuations. Differences in the residual circulation between reanalyses likely contribute to variations in age values.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2021)
Article
Geochemistry & Geophysics
Tianqi Shi, Xin Ma, Ge Han, Zhipeng Pei, Hao Xu, Haowei Zhang, Wei Gong
Summary: In this study, we propose a method to improve the accuracy and precision of CO2 concentration profiles measurements in DIAL. This method combines conditional adjustment with Chebyshev fitting to reduce the error of the retrieved results in the atmospheric boundary layer with a high signal-to-noise ratio. Simulation experiments and real case examinations demonstrate the effectiveness and applicability of our method.
IEEE GEOSCIENCE AND REMOTE SENSING LETTERS
(2022)
Article
Environmental Sciences
Leonie Bernet, Ian Boyd, Gerald Nedoluha, Richard Querel, Daan Swart, Klemens Hocke
Summary: Continuous assessment of stratospheric ozone changes in the southern hemisphere is crucial, with data consistency and uncertainties affecting the resulting trends. Consideration of data uncertainties and inhomogeneities is important for accurate evaluation of ozone trends.
Article
Energy & Fuels
Jianwei Bai, Peijun Cong, Hui Zhang, Shixun Sun, Bowen Zhang, Yong Wang, Liang Wang
Summary: This paper proposes a method based on quantum particle swarm optimization and support vector regression (QPSO-SVR) to effectively predict the contact resistance increment and mass loss of the circuit breaker arc contacts under different arc current conditions. The method has good accuracy and robustness with relative prediction errors of 3.023% and 4.61% for contact resistance increment and mass loss, respectively. The importance rating: 8.5/10.
Article
Construction & Building Technology
Liye Fu, Min Yang, Jianlei Niu, Wei Ren, Ruoyu You
Summary: The new system based on a quantum cascade laser using a quartz-enhanced photoacoustic spectroscopy (QEPAS) sensor can provide detailed real-time SF6 concentrations even when the concentration is changing rapidly, successfully capturing peak SF6 concentrations for all the studies cases. The commercial instrument performed poorly in most studied cases, while the two instruments obtained similar average SF6 concentrations in most cases.
Article
Computer Science, Information Systems
Muhammad Farasat Abbas, Yan Liang He, Guang Yu Sun, An Bang Sun, Elsayed Tag Eldin, Sherif S. M. Ghoneim
Summary: This study measured the inception and breakdown voltages of SF6/CO2 mixed gases at different mixing ratios and pressures using experiments. A 3D particle model was used to investigate the initiation of positive streamers with field ionization. The results showed changes in the inception voltage with different CO2 concentrations, while the simulation results demonstrated an increase in various parameters with increasing CO2 concentration.
Article
Physics, Applied
Dmitry Levko, Laxminarayan L. Raja
Summary: The main aim of this paper is to clarify the influence of the SF6 fraction in the SF6/N-2 mixture on the breakdown voltage. The authors used a two-dimensional axisymmetric fluid model coupled with the comprehensive mechanism of plasma chemical reactions to analyze the influence of various parameters such as the voltage rise time and the SF6 fraction in the mixture. The results of simulations confirmed that the increase in the SF6 fraction in the mixture leads to an increase in the breakdown voltage, which is explained by the influence of the SF6 fraction on the electron attachment rate coefficients.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Chemistry, Physical
Xuan Liu, Mariana C. O. Monteiro, Marc T. M. Koper
Summary: Insights into the mechanism and kinetics of the electrochemical CO2 reduction reaction are limited by the lack of information on interfacial pH. This study combines a reliable pH sensor with the rotating ring-disk electrode technique to investigate the relationship between interfacial pH and CO2 reduction reactions. The results show that interfacial pH increases with increasing current density, and there is a sharp increase at around -0.5 V vs. RHE, indicating a change in buffering species. pH measurements under different conditions further reveal the influence of electrolyte effects on interfacial pH.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Engineering, Chemical
Matteo Vitali, Cristina Zuliani, Francesco Corvaro, Barbara Marchetti, Fabrizio Tallone
Summary: The development of an integrated network for carbon dioxide management requires thorough consideration of all aspects, including pipeline transport safety. Due to limited operating experience with CO2 handling systems, statistical data from hydrocarbon pipelines are often used as a proxy. This study analyzes incident data from onshore CO2 pipelines in the US between 1985 and 2021 to estimate the failure rate for quantitative risk assessments, while acknowledging the limitations of the data.
JOURNAL OF LOSS PREVENTION IN THE PROCESS INDUSTRIES
(2022)
Article
Multidisciplinary Sciences
Pingyi Wang, Jun Yuan, Meili Wang, Mi Wang
Summary: In this study, the vibration process of a fully exposed, isolated smart pebble on a rough bed was measured, and a series of experimental studies with different flow conditions were conducted. The results showed that the pebble motion under turbulence is a nonlinear vibration process, with in-situ and ex-situ strong vibrations. The amplitude of vibration acceleration followed a normal distribution, and the vibration intensity increased before reaching a threshold but weakened afterwards. The sediment vibration frequency was within 20-25 Hz, similar to the flow pulsation frequency, and the near-bed flow velocity was directly related to particle vibration events.
SCIENTIFIC REPORTS
(2023)
Article
Computer Science, Artificial Intelligence
Mengxia Liang, Xiaolong Wang, Shaocong Wu
Summary: In order to improve the accuracy of stock prediction, researchers have applied computer techniques to the financial market and proposed a financial time series classification approach based on aligning change points to help discover hidden temporal correlations, thereby improving stock trend prediction.
Article
Meteorology & Atmospheric Sciences
Clara Orbe, Darryn W. Waugh, Stephen Montzka, Edward J. Dlugokencky, Susan Strahan, Stephen D. Steenrod, Sarah Strode, James W. Elkins, Bradley Hall, Colm Sweeney, Eric J. Hintsa, Fred L. Moore, Emma Penafiel
Summary: The study estimated tropospheric transport using SF6 ages, revealing significant meridional gradients in age near the Southern Hemisphere polar regions and tropics. Observations show a decrease in SF6 age in the Southern Hemisphere, likely due to increasing emissions. Simulations reproduced SF6 age trends, but with a bias towards overestimation in age near emissions regions.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2021)
Article
Environmental Studies
Xinhao Pan, Zichen Wang, Miao Huang, Zhifeng Liu
Summary: By integrating trend-adjusted neighborhood algorithm and automatic rule detection procedure, this study improved the calculation of neighborhood effects in an urban expansion model, leading to increased accuracy in simulating urban expansion. Evaluation using sample cities in China showed that the improved model achieved higher accuracy in terms of spatial matching and urban form similarity, making it applicable for simulating urban expansion in various regions.
Article
Environmental Sciences
Laura Gomez-Martin, Daniel Toledo, Cristina Prados-Roman, Jose Antonio Adame, Hector Ochoa, Margarita Yela
Summary: This study uses the evolution of color index during twilight at high latitudes to detect and characterize polar stratospheric clouds (PSCs). The methodology has been validated by simulations, allowing for classification and estimation of PSC altitude, even in the presence of tropospheric clouds or aerosols. The results are in agreement with meteorological models and satellite observations, showing the potential for long-term observation of PSCs using ground-based spectrometers.
Review
Environmental Sciences
Mingyue Xu, Min Yang, Dong Xie, Jin Ni, Jie Meng, Qunhui Wang, Ming Gao, Chuanfu Wu
Summary: Bibliometric analysis was used to quantitatively evaluate current research trends on composting, indicating that Spain's CSIC, China's Chinese Academy of Sciences, and Canada's Agriculture & Agri-Food Canada are the top research institutes. The research content focuses on heavy metals, biodegradation, and future research hotspots include heavy metal passivator investigation, composting conditioner optimization, and solid waste life cycle assessment improvement.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)
Article
Meteorology & Atmospheric Sciences
Chelsea R. Thompson, Steven C. Wofsy, Michael J. Prather, Paul A. Newman, Thomas F. Hanisco, Thomas B. Ryerson, David W. Fahey, Eric C. Apel, Charles A. Brock, William H. Brune, Karl Froyd, Joseph M. Katich, Julie M. Nicely, Jeff Peischl, Eric Ray, Patrick R. Veres, Siyuan Wang, Hannah M. Allen, Elizabeth Asher, Huisheng Bian, Donald Blake, Ilann Bourgeois, John Budney, T. Paul Bui, Amy Butler, Pedro Campuzano-Jost, Cecilia Chang, Mian Chin, Roisin Commane, Gus Correa, John D. Crounse, Bruce Daube, Jack E. Dibb, Joshua P. DiGangi, Glenn S. Diskin, Maximilian Dollner, James W. Elkins, Arlene M. Fiore, Clare M. Flynn, Hao Guo, Samuel R. Hall, Reem A. Hannun, Alan Hills, Eric J. Hintsa, Alma Hodzic, Rebecca S. Hornbrook, L. Greg Huey, Jose L. Jimenez, Ralph F. Keeling, Michelle J. Kim, Agnieszka Kupc, Forrest Lacey, Leslie R. Lait, Jean-Francois Lamarque, Junhua Liu, Kathryn McKain, Simone Meinardi, David O. Miller, Stephen A. Montzka, Fred L. Moore, Eric J. Morgan, Daniel M. Murphy, Lee T. Murray, Benjamin A. Nault, J. Andrew Neuman, Louis Nguyen, Yenny Gonzalez, Andrew Rollins, Karen Rosenlof, Maryann Sargent, Gregory Schill, Joshua P. Schwarz, Jason M. St Clair, Stephen D. Steenrod, Britton B. Stephens, Susan E. Strahan, Sarah A. Strode, Colm Sweeney, Alexander B. Thames, Kirk Ullmann, Nicholas Wagner, Rodney Weber, Bernadett Weinzierl, Paul O. Wennberg, Christina J. Williamson, Glenn M. Wolfe, Linghan Zeng
Summary: This article provides an overview of the NASA Atmospheric Tomography (ATom) mission and a summary of selected scientific findings to date. ATom was an airborne measurements and modeling campaign aimed at characterizing the composition and chemistry of the troposphere over the most remote regions of the Pacific, Southern, Atlantic, and Arctic Oceans, and examining the impact of anthropogenic and natural emissions on a global scale. ATom data provide crucial insights into global air quality and climate change by understanding the range of chemical species and their reactions in the remote atmosphere. Through extensive measurements and modeling, ATom has yielded significant early findings.
BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY
(2022)
Article
Geosciences, Multidisciplinary
Martina Bramberger, M. Joan Alexander, Sean Davis, Aurelien Podglajen, Albert Hertzog, Lars Kalnajs, Terry Deshler, J. Douglas Goetz, Sergey Khaykin
Summary: Atmospheric waves in the tropical tropopause layer have a significant impact on global climate processes. These waves influence the quasi-biennial oscillation (QBO) and the occurrence of cirrus clouds. However, current climate models struggle to accurately simulate these processes. A new study utilizes profile measurements obtained from a long-duration balloon to understand the effects of fine-scale waves on equatorial cirrus clouds and the QBO. The findings reveal previously unknown small vertical-scale waves with large horizontal extent and multiday periods, which can explain the shortcomings of current climate models. Accurate simulation of these processes has the potential to improve short-term climate predictions.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Chemistry, Analytical
Troy D. Thornberry, Ru-Shan Gao, Steven J. Ciciora, Laurel A. Watts, Richard J. McLaughlin, Angelina Leonardi, Karen H. Rosenlof, Brian M. Argrow, Jack S. Elston, Maciej Stachura, Joshua Fromm, W. Alan Brewer, Paul Schroeder, Michael Zucker
Summary: Uncrewed aerial systems (UASs) are ideal for gathering high-resolution wildfire measurements, but have limited payload capacity. The NightFOX project, funded by NOAA, developed miniaturized scientific instruments for wildfire-related measurements that meet the weight and size constraints of UAS payloads. The system includes three optical instruments with five sensors for mapping wildfires and measuring fire radiative power, as well as a GPS-aided inertial navigation module. The system has been successfully tested on a small UAS and a crewed aircraft.
Editorial Material
Multidisciplinary Sciences
L. M. Polvani, J. Keeble, A. Banerjee, R. Checa-Garcia, G. Chiodo, H. E. Rieder, K. H. Rosenlof
NATURE COMMUNICATIONS
(2023)
Article
Geosciences, Multidisciplinary
Yifeng Peng, Pengfei Yu, Robert W. Portmann, Karen H. Rosenlof, Jiankai Zhang, Cheng-Cheng Liu, Jiangtao Li, Wenshou Tian
Summary: The Pinatubo eruption in 1991 released 10-20 Tg of SO2 into the stratosphere, forming sulfate aerosols. Our modeling results show that volcanic heating significantly affects the chemistry in the tropical stratosphere, including NOx and HOx catalytic cycles. The simulated ozone tendency in the tropics is positive at 20 mb and negative at 10 mb. The study finds that three months after the eruption, the ozone tendency due to homogeneous chemistry becomes more important than heterogeneous chemistry.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Meteorology & Atmospheric Sciences
Luis F. Millan, Gloria L. Manney, Harald Boenisch, Michaela I. Hegglin, Peter Hoor, Daniel Kunkel, Thierry Leblanc, Irina Petropavlovskikh, Kaley Walker, Krzysztof Wargan, Andreas Zahn
Summary: Despite available multi-decadal observations from various platforms, uncertainties in ozone trend estimates in the UTLS region remain large due to natural variability driven by dynamics, constituent transport and mixing. The OCTAV-UTLS activity aims to reduce these uncertainties by accounting for dynamically induced variability. Through the production of dynamical diagnostics, this paper provides a framework for comparing measurements from different platforms and leverages meteorological context to study the impact of dynamical processes on observed UTLS trends. The presented diagnostics can also be applied to other relevant greenhouse gases.
ATMOSPHERIC MEASUREMENT TECHNIQUES
(2023)
Article
Environmental Sciences
Thomas Wagenhauser, Markus Jesswein, Timo Keber, Tanja Schuck, Andreas Engel
Summary: The age of stratospheric air is commonly used in atmospheric models to evaluate transport timescales. The traditional method assumes all air enters the stratosphere through the tropical tropopause, but cross-tropopause transport in the lowermost stratosphere needs to be considered. The new exTR-TR method incorporates extra-tropical input in addition to tropical input to derive more realistic values of transport times in the lowermost stratosphere.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2023)
Article
Environmental Sciences
Sean M. Davis, Nicholas Davis, Robert W. Portmann, Eric Ray, Karen Rosenlof
Summary: This paper investigates the relationship between tropical lower-stratospheric upwelling and lower-stratospheric ozone by analyzing the discrepancy between WACCM-SD simulations and observations. The study finds that the standard configuration of WACCM-SD fails to reproduce the tropical upwelling changes, leading to a spurious negative upwelling trend and an apparent discrepancy in ozone trends. However, a free-running version of WACCM using only surface boundary conditions produces results that are in closer agreement with ozone observations.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2023)
Article
Meteorology & Atmospheric Sciences
J. Douglas Goetz, Lars E. Kalnajs, Terry Deshler, Sean M. Davis, Martina Bramberger, M. Joan Alexander
Summary: A novel fiber-optic distributed temperature sensing instrument, FLOATS, has been developed for continuous in situ profiling of atmospheric temperature. FLOATS utilizes a suspended fiber-optic cable and Raman scattering to provide real-time temperature profiles with a resolution of 3 m at a minimum sampling period of 20 s. The instrument has been successfully tested and demonstrated its capability to detect small-scale gravity waves.
ATMOSPHERIC MEASUREMENT TECHNIQUES
(2023)
Article
Environmental Sciences
Eric Foerster, Harald Boenisch, Marco Neumaier, Florian Obersteiner, Andreas Zahn, Andreas Hilboll, Anna B. Kalisz Hedegaard, Nikos Daskalakis, Alexandros Panagiotis Poulidis, Mihalis Vrekoussis, Michael Lichtenstern, Peter Braesicke
Summary: The number of large urban agglomerations is increasing worldwide, leading to air pollution and greenhouse gas emissions. The EMeRGe campaign investigated emissions from European and Asian major population centres to improve understanding of pollution outflows. Two methods were used to identify and characterize pollution outflows, including using chemical tracers and estimating contributions from source regions.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2023)
Article
Environmental Sciences
Yunqian Zhu, Charles G. Bardeen, Simone Tilmes, Michael J. Mills, Xinyue Wang, V. Lynn Harvey, Ghassan Taha, Douglas Kinnison, Robert W. Portmann, Pengfei Yu, Karen H. Rosenlof, Melody Avery, Corinna Kloss, Can Li, Anne S. Glanville, Luis Millan, Terry Deshler, Nickolay Krotkov, Owen B. Toon
Summary: The January 2022 eruption of Hunga Tonga-Hunga Ha'apai volcano injected a significant amount of water into the stratosphere, which resulted in large perturbations to stratospheric aerosol evolution. The eruption is expected to continue impacting the climate system by increasing aerosol surface area and water vapor until at least October 2022.
COMMUNICATIONS EARTH & ENVIRONMENT
(2022)
Article
Environmental Sciences
Shlomi Ziskin Ziv, Chaim I. Garfinkel, Sean Davis, Antara Banerjee
Summary: The study evaluates the relative importance of QBO and ENSO in controlling stratospheric water vapor concentrations, finding that QBO is more important than ENSO, but nonlinear interactions between the two are significant. Advanced machine learning techniques outperform MLR with only linear relationships considered.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2022)
Article
Environmental Sciences
Helmut Ziereis, Peter Hoor, Jens-Uwe Grooss, Andreas Zahn, Greta Stratmann, Paul Stock, Michael Lichtenstern, Jens Krause, Vera Bense, Armin Afchine, Christian Rolf, Wolfgang Woiwode, Marleen Braun, Joern Ungermann, Andreas Marsing, Christiane Voigt, Andreas Engel, Bjoern-Martin Sinnhuber, Hermann Oelhaf
Summary: During the winter of 2015/2016, the Arctic experienced extremely low temperatures due to a strong polar vortex and the presence of polar stratospheric clouds. The POLSTRACC mission used the German research aircraft HALO to study the lowermost stratosphere in the Arctic region. The measurements of total reactive nitrogen and its partitioning between gas and particle phases provided insights into the processes controlling the ozone budget in the polar winter stratosphere.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2022)