Article
Meteorology & Atmospheric Sciences
Aoqi Zhang, Yilun Chen, Weibiao Li, Shumin Chen
Summary: Based on GPM DPR and Himawari-8 AHI data, event-based investigations were conducted on pre-summer rainy season precipitation over south China. Rain clusters (RCs) were classified into three categories based on cloud-top temperature mode. RCs with cloud-top temperature mode < 230 K were associated with low-level velocity and jet, while RCs with cloud-top temperature mode > 265 K were mainly warm-cloud shallow precipitations triggered by local convection.
INTERNATIONAL JOURNAL OF CLIMATOLOGY
(2023)
Article
Multidisciplinary Sciences
Tsuyoshi Koshiro, Hideaki Kawai, Akira T. Noda
Summary: The response of subtropical marine low cloud cover to global warming is an important and uncertain issue. In this study, using state-of-the-art climate models, it is found that the estimated cloud-top entrainment index consistently decreases with low cloud cover in warmer sea surface temperature conditions, implying a virtually certain positive feedback.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Physics, Fluids & Plasmas
Yarong Zhang, Junlin Fang, Shaofeng Xu, Ying Guo, Jianjun Shi
Summary: A two-dimensional self-consistent fluid model was developed to investigate the ignition process of radio frequency (RF) discharge in an atmospheric helium cascade glow discharge. The model considered the case where a pulsed discharge was excited ahead of the RF discharge by applying pulsed DC voltage and RF voltage to two parallel plate electrodes separately. The spatio-temporal distribution of electron, ion, electric field, and mean electron energy showed that the electron and ion localized in the vicinity of the RF electrode with the extinguishment of the pulsed discharge, while a sheath region formed above the pulsed electrode due to the space charge. This explained the asymmetric ignition of RF discharge in the interelectrode gap observed in experiments. The migration of ions towards the pulsed electrode allowed for stable operation of the RF discharge. Furthermore, the migration time of ions from the RF electrode to the pulsed electrode was estimated to be 3.0 μs, which was consistent with the calculated migration time of ions across the discharge gap.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2023)
Review
Computer Science, Information Systems
Muhamad Najib Zamri, Mohd Shahrizal Sunar
Summary: This article provides an in-depth review of atmospheric cloud modeling methods, analyzing research trends, categorizing methods, and summarizing specific methods, providing a comprehensive understanding for researchers and practitioners.
JOURNAL OF KING SAUD UNIVERSITY-COMPUTER AND INFORMATION SCIENCES
(2022)
Article
Chemistry, Multidisciplinary
Sen Li, Jiazhen Sun, Rui Sun, Jie Pan, Lin Wang, Chen Chen, Qiang Chen, Zhongwei Liu
Summary: This paper investigates the radio frequency dielectric barrier discharge using argon at atmospheric pressure. It observed alpha mode and gamma mode discharges, and analyzed the luminescence intensity at different locations in the discharge gap. It was found that in gamma mode, the negative glow appears with a delay of 13 +/- 1 ns compared to the electron avalanche in alpha mode.
APPLIED SCIENCES-BASEL
(2021)
Article
Geography, Physical
Roberto Fernandez-Moran, Luis Gomez-Chova, Luis Alonso, Gonzalo Mateo-Garcia, Dan Lopez-Puigdollers
Summary: The study aims to provide a solution to correctly obtain the projected clouds based on the estimation of cloud top heights in order to better collocate clouds between sensors and detect their shadows.
ISPRS JOURNAL OF PHOTOGRAMMETRY AND REMOTE SENSING
(2021)
Article
Environmental Sciences
Cynthia Nevison, Xin Lan, Doug Worthy, Hanqin Tian
Summary: Based on the inversion results, the estimation of nitrous oxide emissions in Canada for the period of 2011-2015 is uncertain, and the overall net flux is not significantly different from zero. The emissions in Canadian cropland, mainly located in Alberta, Saskatchewan, and Manitoba, are better resolved with a total flux estimated at 0.08 +/- 0.08 Tg N/yr. The addition of 4 new Canadian sites to the inversion improves the uncertainty, but it remains large due to the low signal to background ratio at all Canadian N2O measurement sites.
ATMOSPHERIC ENVIRONMENT
(2023)
Article
Physics, Applied
Antoine Belinger, Simon Dap, Nicolas Naude
Summary: This study focuses on a diffuse Dielectric Barrier Discharge (DBD) in atmospheric pressure air and investigates the influence of capacitance on the discharge regime. By modifying the dielectric capacitance and using electrical measurements, the effective surface and current density of the discharge were obtained. The results highlight the significance of controlling capacitance to achieve diffuse discharge at high frequency, which has potential applications in atmospheric pressure coating.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Article
Physics, Fluids & Plasmas
Pengying Jia, Kun Gao, Shuai Zhou, Junyu Chen, Jiacun Wu, Kaiyue Wu, Xuechen Li
Summary: This study investigates self-deformation of an atmospheric pressure diffuse discharge initiated between a needle anode and a water cathode, showing a morphological transition from a cone to asymmetric shapes over time. The pH value and electrical conductivity of the water cathode vary during this process. The electrical measurements indicate that the different discharge morphologies may have different formation mechanisms, with conical discharge showing time-invariant behavior while the other two discharges exhibit periodic pulsing. Visual results show that the different discharge morphologies belong to a glow discharge regime, with each type consisting of stationary or moving micro-discharges.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2021)
Article
Meteorology & Atmospheric Sciences
Xueying Cheng, Li Yi, Joerg Bendix
Summary: Cloud top height (CTH) is crucial in Earth's radiation budget and climate change. This study examines the impact of higher-resolution imagery (MODIS) on CTH retrieval, proposing a method combining CETH and cloud top brightness temperature for improved accuracy. Validation over the Arctic Ocean using CALIPSO and radiosonde data shows that the cloud-shadow method (CSM) performs better than operational MODIS CTH product, especially for double-deck cloud systems.
ATMOSPHERIC RESEARCH
(2021)
Article
Meteorology & Atmospheric Sciences
Yuanchong Zhang, Zhonghai Jin, Monika Sikand
Summary: This study aimed to create observation-based cloud radiative kernel datasets and evaluate them through direct comparison with cloud feedback datasets. The results showed that the CRK and CRK-derived cloud feedback were well validated, with the majority of uncertainty coming from CFC. This study also revealed the significance of surface and atmospheric cloud feedback in influencing TOA-alone feedback and the role of atmospheric longwave cloud feedback in enhancing atmospheric energy transport.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2021)
Article
Physics, Fluids & Plasmas
Chen Zhou, Chengxun Yuan, Anatoly Kudryavtsev, T. Yasar Katircioglu, Ismail Rafatov, Jingfeng Yao
Summary: This study focuses on the numerical investigation of dielectric barrier discharge in atmospheric pressure CO2 in a coaxial reactor. Using a numerical model based on the drift-diffusion theory and considering gas heating in a self-consistent manner, the study examines the influence of gas heating on discharge properties and CO2 decomposition across a wide range of applied voltage amplitudes and frequencies. The calculations indicate that neglecting gas heating by assuming a constant (room) gas temperature leads to a significant overestimation of CO2 conversion.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2023)
Article
Environmental Sciences
Xuan Yang, Jinming Ge, Xiaoyu Hu, Meihua Wang, Zihang Han
Summary: Cloud-top heights (CTH) play a significant role in the Earth-atmosphere system, impacting radiation budget, water cycle, and atmospheric circulation. This study compares CTH retrieved from different satellite sensors with ground-based observations and finds that passive satellite sensors show better agreement with surface observations in non-overlapping clouds, while active satellite sensors are more consistent with ground-based radar observations. The accuracy of CTH retrieval is influenced by cloud fraction, cloud geometrical depth, and cloud overlapping, with different sensors displaying varying levels of accuracy and sensitivity to different cloud conditions.
Article
Physics, Applied
Zhiwei Wang, Chunlei Feng, Liang Gao, Chen Liu, Hongbin Ding
Summary: The study investigates the dynamic evolution of plasma optical emission from an array of surface micro-discharges, revealing the interaction between co- and counter-propagating streamers resulting in new streamer fronts with altered velocities and intensities. Additionally, the emergence of secondary streamers is attributed to surface charges accumulated during a prior half cycle and turbulence fluctuations dominated by electrohydrodynamic force.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Environmental Sciences
Karl-Goran Karlsson, Abhay Devasthale, Salomon Eliasson
Summary: This paper examines the quality of global cloud fraction and cloud-top height products provided by the CM SAF cLoud, Albedo and surface RAdiation dataset from the AVHRR data (CLARA-A3) climate data record produced by the EUMETSAT CM SAF. Compared to other cloud CDRs and CALIPSO-CALIOP cloud lidar data, CLARA-A3 shows improved cloud detection, especially over ocean surfaces, and better accuracy in global cloud-top height measurements. The study attempts to estimate trends in observable low-level clouds and finds inconclusive results in the tropics, with small negative trends over oceanic surfaces outside the core tropical region.
Article
Engineering, Aerospace
Ajeet Kumar Maurya, D. Phanikumar, Rajesh Singh, K. Venkatesham, Abhay K. Singh
Summary: This study investigated the impact of a total Lunar Eclipse on the D-region ionosphere using VLF signals recorded in India. The study found anomalous changes in signal amplitudes during the eclipse and estimated lower ionospheric parameters. The decrease in electron density during the eclipse may be due to blocked nighttime ionization by reflected lunar radiation.
ADVANCES IN SPACE RESEARCH
(2022)
Article
Meteorology & Atmospheric Sciences
Ingrid Bjorge-Engeland, Nikolai Ostgaard, Andrey Mezentsev, Chris Alexander Skeie, David Sarria, Jeff Lapierre, Anders Lindanger, Torsten Neubert, Martino Marisaldi, Nikolai Lehtinen, Olivier Chanrion, Kjetil Ullaland, Shiming Yang, Georgi Genov, Freddy Christiansen, Victor Reglero
Summary: This paper presents the observations of 17 Terrestrial Gamma-ray Flashes (TGFs) accompanied by Transient Luminous Events (TLEs). TGFs are highly energetic bursts of gamma photons associated with lightning discharges, while TLEs are concentric rings of UV and visible light at ionospheric altitudes. Short duration TGFs with high peak currents were found to be associated with TLEs, and most of these events occurred over ocean or coastal regions.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2022)
Article
Meteorology & Atmospheric Sciences
A. Lindanger, C. A. Skeie, M. Marisaldi, I Bjorge-Engeland, N. Ostgaard, A. Mezentsev, D. Sarria, N. Lehtinen, V Reglero, O. Chanrion, T. Neubert
Summary: This study provides statistical evidence that Terrestrial Gamma-ray Flashes (TGFs) are generally produced at the initial phase of lightning flashes. In addition, it is shown that there is enhanced lightning activity between 150 and 750 ms following TGFs, indicating a characteristic property of TGF-associated lightning.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2022)
Article
Geosciences, Multidisciplinary
Dongshuai Li, Alejandro Luque, Nikolai G. Lehtinen, F. J. Gordillo-Vazquez, Torsten Neubert, Gaopeng Lu, Olivier Chanrion, Hongbo Zhang, Nikolai Ostgaard, Victor Reglero
Summary: This study investigates lightning initiation inside thunderclouds by monitoring optical emissions and radio observations. The researchers uncover a new type of event that contains multiple optical and radio pulses. The first optical pulse coincides with a strong radio signal, while subsequent optical pulses, delayed by milliseconds, have weaker radio signals, indicating a difference between isolated electrical discharges and lightning-initiating discharges.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Astronomy & Astrophysics
M. D. Caballero-Garcia, Rahul Gupta, S. B. Pandey, S. R. Oates, M. Marisaldi, A. Ramsli, Y-D Hu, A. J. Castro-Tirado, R. Sanchez-Ramirez, P. H. Connell, F. Christiansen, A. Kumar Ror, A. Aryan, J-M Bai, M. A. Castro-Tirado, Y-F Fan, E. Fernandez-Garcia, A. Kumar, A. Lindanger, A. Mezentsev, J. Navarro-Gonzalez, T. Neubert, N. Ostgaard, I. Perez-Garcia, V. Reglero, D. Sarria, T. R. Sun, D-R Xiong, J. Yang, Y-H Yang, B-B Zhang
Summary: We present detailed observations and analysis of GRB 210619B, a very bright and long gamma-ray burst. The energy-resolved prompt emission light curve shows a bright hard emission pulse followed by softer/longer pulses. Spectral analysis suggests a transition from thermal to non-thermal outflow. The late-time data supports a rare hard electron energy index.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Meteorology & Atmospheric Sciences
Dongshuai Li, Alejandro Luque, F. J. Gordillo-Vazquez, F. J. Perez-Invernon, Lasse Skaaning Husbjerg, Torsten Neubert, Olivier Chanrion, Gaopeng Lu, Hongbo Zhang, Jing Han, Nikolai G. Lehtinen, Nikolai Ostgaard, Victor Reglero
Summary: In this study, different types of blue corona discharges associated with Narrow Bipolar Events (NBEs) were analyzed in detail using observations from the Atmosphere-Space Interactions Monitor. Single- and multi-pulse blue corona discharges were both found to be correlated with positive NBEs at the top of thunderstorm clouds, with multi-pulse discharges having weaker currents than single-pulse discharges. The joint analysis of optical and radio observations estimated the photon free mean path at the cloud top to be around 6 m.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2023)
Review
Multidisciplinary Sciences
Torsten Neubert, Francisco J. Gordillo-Vazquez, Heidi Huntrieser
Summary: The International Space Station is an ideal platform for observing thunderstorms and their electrification. In the coming years, meteorological satellites in geostationary orbit and Earth-observing satellite instruments in both geostationary and low-Earth orbit will provide even more advanced observations. These new observations can greatly contribute to our understanding of thunderstorms' effects on atmospheric dynamics and climate change.
Article
Meteorology & Atmospheric Sciences
Xue Bai, Martin Fullekrug, Olivier Chanrion, Serge Soula, Adam Peverell, Dakalo Mashao, Michael Kosch, Lasse Husbjerg, Nikolai Ostgaard, Torsten Neubert, Victor Reglero
Summary: Simultaneous photometric observations of thundercloud discharges from ASIM on the International Space Station and ground-based electric field measurements in South Africa were analyzed. A blue discharge with strong electric fields was recorded by ASIM during its flight over an extended thunderstorm front. The height of the blue discharge was estimated to be around 10.9-16.5 km based on the rising edge of the photomultiplier tube light pulse and was inferred to be around 16.0-18.8 km using skywave arrival times. The height determinations were found to be consistent with each other and the possibility of an overshooting cloud top was discussed. The height of blue discharges plays a significant role in understanding their impact on upper tropospheric chemistry.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2023)
Article
Meteorology & Atmospheric Sciences
Maja Tomicic, Olivier Chanrion, Thomas Farges, Janusz Mlynarczyk, Ivana Kolmasova, Serge Soula, Jeff Lapierre, Christoph Kohn, Torsten Neubert
Summary: Powerful lightning generates electromagnetic pulses (EMPs) and quasi-static electric fields (QE) that affect the lower ionosphere. These disturbances manifest as optical phenomena called elves, sprites, and halos, as well as changes in radio signals passing through the affected region. Through analyzing 63 elves and corresponding radio signal perturbations from a stationary thunderstorm system, this study untangles the relationship between the perturbations and lightning characteristics. The findings indicate that lightning with elves has three times the power and impulse charge moment change compared to lightning without elves. It is also proposed that some perturbations without optical emissions may be related to regions of reduced conductivity caused by electron attachment/detachment processes or dimly detected electron enhancements associated with transient luminous events (TLEs).
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2023)
Article
Meteorology & Atmospheric Sciences
Dongshuai Li, Torsten Neubert, Lasse Skaaning Husbjerg, Yanan Zhu, Olivier Chanrion, Jeff Lapierre, Alejandro Luque, Christoph Kohn, Matthias Heumesser, Krystallia Dimitriadou, Martin Stendel, Eigil Kaas, Emilie Petrea Petajamaa Wiinberg Olesen, Feifan Liu, Nikolai Ostgaard, Victor Reglero
Summary: Blue corona discharges, observed at the top of thunderclouds, were found to be associated with deep convection and increased lightning activity. This study provides important microphysical parameters related to blue corona discharges based on observations and measurements, establishing a reference for future studies.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2023)
Review
Geosciences, Multidisciplinary
Anna Rutgersson, Erik Kjellstrom, Jari Haapala, Martin Stendel, Irina Danilovich, Martin Drews, Kirsti Jylha, Pentti Kujala, Xiaoli Guo Larsen, Kirsten Halsnaes, Ilari Lehtonen, Anna Luomaranta, Erik Nilsson, Taru Olsson, Jani Sarkka, Laura Tuomi, Norbert Wasmund
Summary: Natural hazards are extreme events that occur naturally and have negative effects on people and the environment. Understanding their causes, likelihood, and consequences helps society be better prepared and develop adaptation strategies. In the Baltic Sea region, natural hazards related to climate change are identified as a significant challenge. This study summarizes existing knowledge about extreme events in the region, including storms, waves, sea level changes, floods, and their implications for society and ecosystems.
EARTH SYSTEM DYNAMICS
(2022)