Article
Environmental Sciences
Yifan Zhan, Fan Yi, Fuchao Liu, Yunpeng Zhang, Changming Yu, Jun Zhou
Summary: The study identified a total of 3047 individual shallow cumuli in Wuhan, China over a period of 9 years. These clouds were found to occur at the top edge of the convective boundary layer, with short duration and heights ranging from approximately 50-560 meters. They were most common in high temperature and high water vapor conditions.
Article
Environmental Sciences
Zhenxing Liu, Jianhua Chang, Hongxu Li, Sicheng Chen, Tengfei Dai
Summary: In this paper, a machine learning method called the MKnm algorithm is proposed to estimate ABLH under complex atmospheric conditions. Compared to other methods, MKnm performs well in tracking the diurnal variation of ABLH and provides accurate estimations.
Article
Environmental Sciences
Ting-Yu Chiang, Wei-Nai Chen, Charles C. -K. Chou, Shih-Yu Chang, Tzu-Shuan Wu
Summary: Variations in the height of the boundary layer have a critical impact on the vertical transport of near-surface aerosols, affecting their interactions with clouds, solar radiation, and regional climate. This study analyzed air pollution and meteorological factors in an urban area and its peripheral mountainous region, exploring the differences in aerosol characteristics and transport mechanisms. The findings provide a theoretical basis for future air pollution prevention and regional climate research.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Environmental Sciences
Chen Zuo, Jiayi Chen, Yue Zhang, Yize Jiang, Mingyuan Liu, Huiming Liu, Wenji Zhao, Xing Yan
Summary: This study evaluates four meteorological reanalysis datasets in China and finds that ERA5 is the most accurate in terms of temperature, relative humidity, wind speed, and boundary layer height, while FNL has the highest uncertainty. The spatial accuracy of all datasets is higher in the eastern region compared to the western region due to complex terrain and limited ground-based observations. ERA5 performs the best in retrieving PM2.5 in China, providing a useful guideline for subsequent satellite-based PM2.5 retrieval studies in the country.
ATMOSPHERIC ENVIRONMENT
(2023)
Article
Environmental Sciences
Zhijuan Zhang, Ling Mu, Chen Li
Summary: The planetary boundary layer height plays a crucial role in the atmosphere, and this study compares the estimates of boundary layer height by AD-Net and ECMWF. The results show that AD-Net performs well in estimating boundary layer height, with some significant discrepancies noted between AD-Net and ECMWF in certain regions and seasons.
Article
Environmental Sciences
Aurelie Riandet, Irene Xueref-Remy, Ioana Popovici, Ludovic Lelandais, Alexandre Armengaud, Philippe Goloub
Summary: This study investigates the diurnal and seasonal variability in the atmospheric boundary-layer height (ABLH) in Marseille for the mistral and sea/land breeze wind patterns. A lidar using a Haar wavelet method was used to extract the ABLH data. The results show that the ABLH reaches to about 1000 m during mistral conditions, with a diurnal amplitude of 650-740 m, and is lower during sea/land breeze situations.
Article
Meteorology & Atmospheric Sciences
Pablo Ortiz-Amezcua, Juana Andujar-Maqueda, Antti J. Manninen, Pyry Pentikainen, Ewan J. O'Connor, Iwona S. Stachlewska, Gregori de Arruda Moreira, Jose Antonio Benavent-Oltra, Juan Andres Casquero-Vera, Patryk Poczta, Dongxiang Wang, Kamila M. Harenda, Bogdan H. Chojnicki, Dominika M. Szczepanik, Lucja Janicka, Dirk Schuttemeyer, Lucas Alados-Arboledas, Juan Luis Guerrero-Rascado
Summary: This study characterized the Atmospheric Boundary Layer (ABL) over two middle-latitude rural sites using Doppler lidar. The results showed the strong influence of clouds on ABL development and provided recommendations for improving the classification algorithm.
ATMOSPHERIC RESEARCH
(2022)
Article
Environmental Sciences
Tamir Tzadok, Ayala Ronen, Dorita Rostkier-Edelstein, Eyal Agassi, David Avisar, Sigalit Berkovic, Alon Manor
Summary: Measurements using Halo-Photonics StreamLine XR Doppler LiDAR show good agreement with in situ instruments, with lower elevation scans performing the best. Analysis of boundary layer structure and verification of multiple inversions were conducted using retrieved data and WRF simulations. Synergistic use of LiDAR data with WRF simulations for low SNR regions was demonstrated.
Article
Optics
Feiyue Mao, Mengdi Zhao, Wei Gong, Liuzhu Chen, Zhenxing Liang
Summary: This study proposed a new layer detection algorithm based on automatic segmentation method with minimum cost function, which showed higher detection efficiency compared to SIBYL by identifying 21% and 13% more layers at resolutions of 1 km and 1-5 km respectively. The new algorithm also improves the accuracy and resolution of layer products from CALIPSO and other space-based lidars.
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
(2021)
Article
Meteorology & Atmospheric Sciences
G. Noual, Y. Brunet, P. Le Moigne, C. Lac
Summary: Evidence has shown that land-cover changes, such as deforestation, can impact cloudiness and precipitation, although conflicting results have been obtained at different scales and places, revealing a poor understanding of the involved physical processes. In this study, the authors focused on mesoscale summer cloudiness influenced by the Landes forest in France, and successfully simulated the higher summer cloud cover over the forest compared to its surroundings. They found that the larger sensible heat flux and higher roughness of the forest were the main drivers of cloudiness.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2023)
Article
Meteorology & Atmospheric Sciences
Futing Wang, Ting Yang, Zifa Wang, Xi Chen, Haibo Wang, Jianping Guo
Summary: This study evaluated the performance of nine lidar algorithms under different pollution scenarios in retrieving PBLH, with GM, LGM, CRGM, IPM, VAR, VGM, WCT, WCTD, and POLARIS showing varying capabilities under different conditions. The comprehensive comparison provides guidance on selecting the appropriate algorithm for specific atmospheric conditions.
ATMOSPHERIC RESEARCH
(2021)
Article
Environmental Sciences
Bisen Han, Tian Zhou, Xiaowen Zhou, Shuya Fang, Jianping Huang, Qing He, Zhongwei Huang, Minzhong Wang
Summary: This study proposes a new method to determine the atmospheric boundary layer height (ABLH) and compares it with existing methods. The results show that the new method is consistent with the existing methods for non-dust events, but overestimates the stable boundary layer and underestimates the heights of the mixing layer.
Article
Environmental Sciences
Ya'ni Pan, Zhili Jin, Pengfei Tong, Weiwei Xu, Wei Wang
Summary: The boundary layer height (BLH) is a critical parameter in atmospheric numerical models, and the edge detection (ED) method outperforms traditional methods in nighttime and extreme atmospheric conditions by automatically identifying the edges of BLHs. By avoiding the influence of extreme atmospheric conditions, the ED method provides more accurate BLH estimates.
Article
Environmental Sciences
Gemine Vivone, Giuseppe D'Amico, Donato Summa, Simone Lolli, Aldo Amodeo, Daniele Bortoli, Gelsomina Pappalardo
Summary: The atmospheric boundary layer (ABL) is the lowest part of the atmosphere that directly contacts the Earth's surface. Estimating its depth is crucial for meteorology and pollution studies. Remote sensing sources can help improve the spatial and temporal measurements of ABL height (ABLH), with aerosol backscatter profiles commonly used for this purpose. Scientists are working on developing automatic ABLH retrieval algorithms using lidar observations.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2021)
Article
Meteorology & Atmospheric Sciences
S. Anisimov, S. Galichenko, K. Aphinogenov, E. Klimanova, A. A. Prokhorchuk, A. S. Kozmina, A. Guriev
Summary: In this study, researchers used a tethered balloon equipped with an instrumented platform to examine the altitude distribution of key quantities in the lowest atmospheric region of the global electric circuit. Through spaced observations, they were able to analyze spatial and temporal changes in electrical quantities in the atmospheric boundary layer more effectively. The study also found long-lived space charge layers, estimated charge densities in atmospheric columns of various thicknesses, and quantified columnar electrical resistance, electric potential, and electromotive force in fair-weather conditions in the ABL.
ATMOSPHERIC RESEARCH
(2021)
Article
Geosciences, Multidisciplinary
Naga Oshima, Seiji Yukimoto, Makoto Deushi, Tsuyoshi Koshiro, Hideaki Kawai, Taichu Y. Tanaka, Kohei Yoshida
PROGRESS IN EARTH AND PLANETARY SCIENCE
(2020)
Article
Geosciences, Multidisciplinary
Chris D. Jones, Jonathan E. Hickman, Steven T. Rumbold, Jeremy Walton, Robin D. Lamboll, Ragnhild B. Skeie, Stephanie Fiedler, Piers M. Forster, Joeri Rogelj, Manabu Abe, Michael Botzet, Katherine Calvin, Christophe Cassou, Jason N. S. Cole, Paolo Davini, Makoto Deushi, Martin Dix, John C. Fyfe, Nathan P. Gillett, Tatiana Ilyina, Michio Kawamiya, Maxwell Kelley, Slava Kharin, Tsuyoshi Koshiro, Hongmei Li, Chloe Mackallah, Wolfgang A. Mueller, Pierre Nabat, Twan van Noije, Paul Nolan, Rumi Ohgaito, Dirk Olivie, Naga Oshima, Jose Parodi, Thomas J. Reerink, Lili Ren, Anastasia Romanou, Roland Seferian, Yongming Tang, Claudia Timmreck, Jerry Tjiputra, Etienne Tourigny, Kostas Tsigaridis, Hailong Wang, Mingxuan Wu, Klaus Wyser, Shuting Yang, Yang Yang, Tilo Ziehn
Summary: The models show reduced aerosol amounts in 2020, particularly over southern and eastern Asia, leading to increased surface shortwave radiation levels. However, the impact on near-surface temperature or rainfall during 2020-2024 is extremely small and not detectable in this initial analysis. Further regional analyses and closer attention to extremes are needed to evaluate the impact of COVID-19-related emission reductions on near-term climate.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Meteorology & Atmospheric Sciences
M. Kikuchi, H. Okamoto, K. Sato
Summary: The study focuses on horizontal ice plates in clouds using satellite lidar measurements. It shows that tilting affects ice plate detection, decreasing it by 81.7%, with only 30.8% able to be recovered. However, geographical characteristics of ice plates are still preserved during off-nadir periods, hinting at potential undiscovered climatological information on ice plates in future observations.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2021)
Article
Geochemistry & Geophysics
Hideaki Kawai, Tsuyoshi Koshiro, Seiji Yukimoto
Summary: The study found that improvements in radiative flux did help alleviate the double-ITCZ problem, but it cannot be completely resolved by improvements in radiative flux alone, indicating that there may be other underlying causes contributing to the issue.
ATMOSPHERIC SCIENCE LETTERS
(2021)
Article
Geochemistry & Geophysics
Yuichiro Hagihara, Yuichi Ohno, Hiroaki Horie, Woosub Roh, Masaki Satoh, Takuji Kubota, Riko Oki
Summary: This study investigated the impact of horizontal integration and unfolding methods on reducing Doppler measurement errors and simulated Doppler velocities in cirrus cloud and precipitation cases. The results showed that Doppler errors can be significantly reduced by applying appropriate horizontal integration and unfolding methods.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2022)
Article
Geosciences, Multidisciplinary
Dimitra Konsta, Jean-Louis Dufresne, Helene Chepfer, Jessica Vial, Tsuyoshi Koshiro, Hideaki Kawai, Alejandro Bodas-Salcedo, Romain Roehrig, Masahiro Watanabe, Tomoo Ogura
Summary: Several studies have shown that most climate models underestimate cloud cover and overestimate cloud reflectivity, particularly for the tropical low-level clouds. Through analyzing the characteristics of low-level tropical marine clouds simulated by six climate models, it is found that these models still exhibit a bias of too few and too bright clouds, and the reflectivity is particularly overestimated when cloud cover is low.
GEOPHYSICAL RESEARCH LETTERS
(2022)
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
Geosciences, Multidisciplinary
Yusuke Ushijima, Hiroyuki Tsujino, Kei Sakamoto, Masayoshi Ishii, Tsuyoshi Koshiro, Naga Oshima
Summary: The observed sea level around the Japanese coast exhibits a long-term multidecadal variation that is likely forced. Climate model simulations indicate that the increase in anthropogenic aerosols and greenhouse gases caused the fall and rise of the sea level, respectively. Particularly, the increase in surface heat loss in the North Pacific due to anthropogenic aerosols has a dominant role in the sea level fall.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Meteorology & Atmospheric Sciences
Hideaki Kawai, Kohei Yoshida, Tsuyoshi Koshiro, Seiji Yukimoto
Summary: Parameter tuning is well-known to impact the performance of Global Climate Models. However, other implementation details, such as limits and thresholds of variables, can also significantly affect model performance. These minor-looking treatments sometimes have comparable or even larger impacts than advanced parameterizations based on theory and observation.
JOURNAL OF ADVANCES IN MODELING EARTH SYSTEMS
(2022)
Article
Meteorology & Atmospheric Sciences
Timothy Andrews, Alejandro Bodas-Salcedo, Jonathan M. Gregory, Yue Dong, Kyle C. Armour, David Paynter, Pu Lin, Angshuman Modak, Thorsten Mauritsen, Jason N. S. Cole, Brian Medeiros, James J. Benedict, Herve Douville, Romain Roehrig, Tsuyoshi Koshiro, Hideaki Kawai, Tomoo Ogura, Jean-Louis Dufresne, Richard P. Allan, Chunlei Liu
Summary: The pattern of sea-surface temperature change has a significant impact on radiative feedback. The Earth experienced warming with feedbacks consistent with long-term climate sensitivity feedbacks over the historical record. However, unusual trends in tropical Pacific SSTs and cooling in the Southern Ocean post 1980 led to climate feedback becoming uncorrelated with expected long-term CO2 increase, indicating lower climate sensitivity.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2022)
Article
Meteorology & Atmospheric Sciences
Yuichiro Hagihara, Yuichi Ohno, Hiroaki Horie, Woosub Roh, Masaki Satoh, Takuji Kubota
Summary: This study investigates the Doppler measurement errors of the EC-CPR on the EarthCARE satellite by increasing the amount of data used and extending the data coverage globally. The errors were evaluated for both low and high pulse repetition frequency settings. The results showed that the errors were significantly reduced after unfolding correction, with the error values ranging from 0.63 m/s to 2.2 m/s for the low PRF setting and from 0.29 m/s to 0.78 m/s for the high PRF setting.
ATMOSPHERIC MEASUREMENT TECHNIQUES
(2023)
Article
Meteorology & Atmospheric Sciences
Takashi Maki, Taichu Y. Tanaka, Tsuyoshi Koshiro, Atsushi Shimizu, Tsuyoshi T. Sekiyama, Mizuo Kajino, Yasunori Kurosaki, Toshiya Okuro, Naga Oshima
Summary: Ensemble future climate projections using the MRI-ESM2.0 model showed that sand and dust storm (SDS) emissions in the Gobi Desert are projected to increase in spring and autumn with warmer climate scenarios, due to changes in friction velocity and erodibility. The model also reproduced the decreasing trend of SDS emissions in the early 21st century. Friction velocity and ground temperature were found to be highly correlated with SDS emissions.
Article
Geosciences, Multidisciplinary
Claudia Tebaldi, Kevin Debeire, Veronika Eyring, Erich Fischer, John Fyfe, Pierre Friedlingstein, Reto Knutti, Jason Lowe, Brian O'Neill, Benjamin Sanderson, Detlef van Vuuren, Keywan Riahi, Malte Meinshausen, Zebedee Nicholls, Katarzyna B. Tokarska, George Hurtt, Elmar Kriegler, Jean-Francois Lamarque, Gerald Meehl, Richard Moss, Susanne E. Bauer, Olivier Boucher, Victor Brovkin, Young-Hwa Byun, Martin Dix, Silvio Gualdi, Huan Guo, Jasmin G. John, Slava Kharin, YoungHo Kim, Tsuyoshi Koshiro, Libin Ma, Dirk Olivie, Swapna Panickal, Fangli Qiao, Xinyao Rong, Nan Rosenbloom, Martin Schupfner, Roland Seferian, Alistair Sellar, Tido Semmler, Xiaoying Shi, Zhenya Song, Christian Steger, Ronald Stouffer, Neil Swart, Kaoru Tachiiri, Qi Tang, Hiroaki Tatebe, Aurore Voldoire, Evgeny Volodin, Klaus Wyser, Xiaoge Xin, Shuting Yang, Yongqiang Yu, Tilo Ziehn
Summary: The Scenario Model Intercomparison Project (ScenarioMIP) presents a range of outcomes regarding global climate projections, focusing on geophysical analysis. By comparing CMIP6 projections with CMIP5 results, it is found that there are more variations in future temperature changes than previously thought.
EARTH SYSTEM DYNAMICS
(2021)
Proceedings Paper
Engineering, Electrical & Electronic
Hajime Okamoto, Kaori Sato, Masahiro Fujikawa, Eiji Oikawa, Tomoaki Nishizawa, Shoken Ishii, Yoshitaka Jin, Makoto Aoki, Nobuo Sugimoto
29TH INTERNATIONAL LASER RADAR CONFERENCE (ILRC 29)
(2020)
Proceedings Paper
Engineering, Electrical & Electronic
Masahiro Fujikawa, Rei Kudo, Tomoaki Nishizawa, Eiji Oikawa, Akiko Higurashi, Hajime Okamoto
29TH INTERNATIONAL LASER RADAR CONFERENCE (ILRC 29)
(2020)