Article
Environmental Sciences
Xiaoyong Zhuge, Xiaolei Zou, Xin Li, Fei Tang, Bin Yao, Lu Yu
Summary: This study investigated the seasonal and diurnal variations in cloud-top phase over the western North Pacific using data from the Japanese Himawari-8 satellite. Results showed differences in the frequency of ice and water clouds between seasons, with water clouds more associated with lower tropospheric moisture than sea surface temperature. The region east of Hokkaido has a high frequency of water clouds in summer due to moist air mass transport and ocean currents.
Article
Geochemistry & Geophysics
Xiaoyong Zhuge, Xiaolei Zou, Yuan Wang
Summary: An algorithm for determining the infrared cloud-top phase for advanced Himawari imager measurements is developed and compared with the Moderate Resolution Imaging Spectroradiometer algorithm, showing different decision tree and test methods. The verification results indicate high hit rates for liquid-water and ice cloud tops. Intercomparisons between AHI and MODIS IR cloud-top phase products reveal some limitations of the MODIS algorithm and dependencies on MODIS zenith angles for liquid-water phase classifications.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2021)
Article
Environmental Sciences
Jie Yang, Chuanfeng Zhao, Yue Sun, Yulei Chi, Yikun Yang
Summary: This study investigates the relationships between aerosol optical depth (AOD) and cloud properties, as well as the aerosol first indirect effect (FIE), using 10-year observation data. The results show that aerosols have a significant impact on cloud droplets and cloud radiative effects, especially when AOD is low and liquid water path is high.
ATMOSPHERIC ENVIRONMENT
(2022)
Article
Geosciences, Multidisciplinary
Harshbardhan Kumar, Shani Tiwari
Summary: In this study, the aerosol-cloud dataset over the Northern Indian Ocean (NIO) for 18 years (2003-2020) was analyzed to assess the climatology and trend of aerosol and cloud characteristics. The results showed significant spatio-temporal variations in aerosol and cloud parameters, with higher aerosol loading along the Indian sub-continent and lower loading over the equatorial open ocean. Cloud properties also showed variations, with thicker convective clouds over the southern Bay of Bengal and thinner shallow clouds over the northwestern Arabian Sea. Trend analysis revealed increasing aerosol loading and cloud properties, except for cloud optical depth, cloud top temperature, and cloud top pressure, which showed negative trends.
GEOSCIENCE FRONTIERS
(2023)
Article
Meteorology & Atmospheric Sciences
Paul C. Loikith, Deepti Singh, Graham P. Taylor
Summary: This study assesses the projected changes in atmospheric ridges and associated temperature and precipitation anomalies in the Pacific-North American region for the end of the twenty-first century. The results show a decrease in ridge days in fall through spring and an increase in ridge days in summer. The study also reveals that future ridges will exhibit similar temperature and precipitation anomaly associations as in the historical climate period.
JOURNAL OF CLIMATE
(2022)
Article
Meteorology & Atmospheric Sciences
Yuling Yao, Yang Zhang, Kevin i. Hodges, Talia Tamarin-Brodsky
Summary: Extratropical cyclones (ETCs) are complex weather systems with diverse vertical structures and distinct characteristics. This study classified North Pacific ETCs into deep cyclones, shallow low-level cyclones, and shallow upper-level cyclones, and tracked them using a Lagrangian perspective. The analysis revealed different mechanisms for the propagation of deep and shallow ETCs, including diabatic heating and horizontal advection for deep cyclones, and nonlinear advection terms for shallow cyclones.
JOURNAL OF CLIMATE
(2023)
Article
Environmental Sciences
Siyu Meng, Xun Gong, Yang Yu, Xiaohong Yao, Xiang Gong, Keyu Lu, Chao Zhang, Jie Shi, Xiaojie Yu, Huiwang Gao
Summary: The study found that the North Pacific ocean desert has experienced oligotrophication and expansion over the past 20 years, which is related to warming upper oceans in most regions, but the Chl-a variations in the southwest area are linked to regional changes in sea surface heights. Additionally, the insignificant shift in the mean position of NPOD is likely controlled by the Pacific decadal oscillation processes.
ENVIRONMENTAL RESEARCH LETTERS
(2021)
Article
Oceanography
Ling Ling Liu, Rui Xin Huang, Fan Wang
Summary: A new three-dimensional method is proposed for calculating the annual mean subduction and obduction rate in the ocean, which can provide the three-dimensional feature and more accurate distribution of the annual subduction and obduction rate in density space. The new method greatly improves the density structure of subducted and obducted water mass.
JOURNAL OF PHYSICAL OCEANOGRAPHY
(2023)
Article
Geosciences, Multidisciplinary
Samuel C. Mogen, Nicole S. Lovenduski, Allysa R. Dallmann, Luke Gregor, Adrienne J. Sutton, Steven J. Bograd, Nathali Cordero Quiros, Emanuele Di Lorenzo, Elliott L. Hazen, Michael G. Jacox, Mercedes Pozo Buil, Stephen Yeager
Summary: This study characterizes the biogeochemical properties of the Eastern North Pacific upper ocean during the Winter of 2013-2014 using observations and models, and finds that the Blob is associated with increased aragonite saturation and decreased oxygen concentration.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Meteorology & Atmospheric Sciences
Hiroaki Ueda, Masaya Kuramochi, Koutarou Takaya, Yuhei Takaya, Saki Asano, Shuhei Maeda
Summary: The study investigates the formation mechanisms of Upper-tropospheric anticyclones (UTACs) in the Asian-Australian-western Pacific sector, revealing different processes for the seasonal UTACs during Asian summer and winter.
JOURNAL OF CLIMATE
(2022)
Article
Meteorology & Atmospheric Sciences
Kenta Kawasaki, Yoshihiro Tachibana, Tetsu Nakamura, Koji Yamazaki
Summary: The Okhotsk Sea, with its colder temperatures in summer compared to the surrounding continent, has a remote impact on summer climates; ideal numerical experiments show that the presence of the Okhotsk Sea strengthens precipitation in the western North Pacific and intensifies the subtropical high pressure system.
JOURNAL OF CLIMATE
(2021)
Article
Geosciences, Multidisciplinary
Kazutoshi Sato, Jun Inoue
Summary: The study found that the distribution of low-tropospheric ice clouds in Antarctica and the Southern Ocean is influenced by temperature, with marine aerosols acting as ice-nucleating particles in both summer and winter.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Multidisciplinary Sciences
Ruiqiang Ding, Yu-Heng Tseng, Emanuele Di Lorenzo, Liang Shi, Jianping Li, Jin-Yi Yu, Chunzai Wang, Cheng Sun, Jing-Jia Luo, Kyung-Ja Ha, Zeng-Zhen Hu, Feifei Li
Summary: The authors find that persistent two-way teleconnections between the North Pacific Oscillation and the tropical Pacific are a key source of multi-year El Nino events. These teleconnections lead to the prolonged El Nino phenomena, resulting in severe floods and droughts worldwide with significant socioeconomic impacts. Model experiments and future projections suggest that with enhanced NPO variability under future anthropogenic forcing, more frequent multi-year El Nino events should be expected. Therefore, properly accounting for the effects of the NPO on the evolution of El Nino events may improve multi-year El Nino prediction and projection.
NATURE COMMUNICATIONS
(2022)
Article
Meteorology & Atmospheric Sciences
Ganadhi Mano Kranthi, Medha Deshpande, Khadgarai Sunilkumar, Rongmie Emmanuel, Sopan Ingle
Summary: The study reveals a significant increasing trend of rapid intensification (RI) for tropical cyclones over the Arabian Sea (AS) in the past 39 years. RI TCs have longer lifespans, higher wind speeds, and a higher likelihood of reaching super cyclonic storm category. RI onset typically occurs during the depression stage.
INTERNATIONAL JOURNAL OF CLIMATOLOGY
(2023)
Article
Chemistry, Analytical
Miming Zhang, Christa A. Marandino, Jinpei Yan, Qi Lin, Keyhong Park, Guojie Xu
Summary: This study investigates the sea-to-air flux of DMS in the Southern Ocean, southeast Indian Ocean, and northwest Pacific Ocean, and its impact on sulfate aerosols. Two large-scale DMS sources were found in the marginal sea ice zone and South Subtropical Front. Inconsistencies between atmospheric sulfate compounds and DMS emissions along the cruise track were attributed to horizontal advection of air masses.
ENVIRONMENTAL CHEMISTRY
(2021)
Article
Meteorology & Atmospheric Sciences
Greg M. McFarquhar, Christopher S. Bretherton, Roger Marchand, Alain Protat, Paul J. DeMott, Simon P. Alexander, Greg C. Roberts, Cynthia H. Twohy, Darin Toohey, Steve Siems, Yi Huang, Robert Wood, Robert M. Rauber, Sonia Lasher-Trapp, Jorgen Jensen, Jeffrey L. Stith, Jay Mace, Junshik Um, Emma Jaervinen, Martin Schnaiter, Andrew Gettelman, Kevin J. Sanchez, Christina S. McCluskey, Lynn M. Russell, Isabel L. McCoy, Rachel L. Atlas, Charles G. Bardeen, Kathryn A. Moore, Thomas C. J. Hill, Ruhi S. Humphries, Melita D. Keywood, Zoran Ristovski, Luke Cravigan, Robyn Schofield, Chris Fairall, Marc D. Mallet, Sonia M. Kreidenweis, Bryan Rainwater, John D'Alessandro, Yang Wang, Wei Wu, Georges Saliba, Ezra J. T. Levin, Saisai Ding, Francisco Lang, Son C. H. Truong, Cory Wolff, Julie Haggerty, Mike J. Harvey, Andrew R. Klekociuk, Adrian McDonald
Summary: Projects between 2016 and 2018 conducted comprehensive measurements of thermodynamics, surface radiation, cloud, precipitation, aerosol, and other factors over the Southern Ocean cold waters. Findings indicate a high dependence of cloud properties on aerosols, and the importance of dynamics and turbulence in driving cloud phase heterogeneity.
BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY
(2021)
Article
Geosciences, Multidisciplinary
Wenhui Zhao, Yi Huang, Steven Siems, Michael Manton
Summary: The study revealed a significant negative correlation between total cloud cover anomaly (TCCA) and lagged sea surface temperature anomaly (SSTA) in the Great Barrier Reef region, which is greater in magnitude and spatial extent compared to the SSTA-ENSO correlation. This suggests that local-scale reduced cloud cover plays a crucial role in the formation of warm shallow water and occurrence of thermal coral bleaching events in the region.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Engineering, Civil
Belinda Roux, Rodney Potts, Steven Siems, Michael Manton
Summary: The study at Perth Airport found that radiation fog was the most prevalent type of fog, with the majority of fog events occurring in the cool season. Through clustering analysis, it was determined that most fog events occurred in a post-frontal/trough system with a high-pressure system. The results supported the theory that fog formation is often due to increased stability caused by nocturnal cooling and the decoupling between moist westerlies and surface flow at Perth Airport caused by local topography.
JOURNAL OF HYDROLOGY
(2021)
Article
Meteorology & Atmospheric Sciences
Luis Ackermann, Yi Huang, Steven Siems, Michael Manton, Francisco Lang, Thomas Chubb, Andrew Peace, Johanna Speirs, Kenyon Suzanne, Alain Protat, Simon P. Alexander
Summary: Understanding the mechanisms behind precipitation in the Snowy Mountains region of southeast Australia, particularly the role of cold fronts and orography, can help improve precipitation forecasts and water management. Observations showed that precipitation events were associated with cold front passages, with a significant amount occurring under blocked conditions likely due to orographic enhancement. Additionally, orographic convection invigoration and unblocked stratiform enhancement were identified as key mechanisms driving precipitation during specific events, with different processes dominating ice particle growth before and after frontal passages.
JOURNAL OF HYDROMETEOROLOGY
(2021)
Article
Meteorology & Atmospheric Sciences
Yi Huang, Steven T. Siems, Michael J. Manton
Summary: The study analyzed in-situ observations of mid-latitude shallow convective clouds over the Southern Ocean during three Austral winters, focusing on cloud microphysical properties and natural variability. Results showed the prevalence of supercooled liquid water and the primary ice nucleation mechanism as the freezing of supercooled raindrops. Additionally, high ice particle concentrations were observed at temperatures warmer than -12 degrees C, indicating the operation of secondary ice production mechanisms.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2021)
Article
Meteorology & Atmospheric Sciences
Suma Bhanu Battula, Steven Siems, Arpita Mondal
Summary: This study categorizes the precipitation regimes in the Western Himalayas into seven clusters using a clustering algorithm. The results highlight the dominant contribution of monsoonal regimes to precipitation and propose a methodology to identify precipitation hotspots in vulnerable higher elevations.
INTERNATIONAL JOURNAL OF CLIMATOLOGY
(2022)
Article
Meteorology & Atmospheric Sciences
Son C. H. Truong, Yi Huang, Steven T. Siems, Michael J. Manton, Francisco Lang
Summary: This study evaluates the thermodynamic structure of the lower troposphere in the ERA5 reanalysis against high-resolution upper air soundings collected over the Southern Ocean. The reanalysis is found to accurately depict the general synoptic meteorology and thermodynamic structure, but shows a significant reduction in the inferred cloud layers, thinner cloud geometric layer, and shallower cloud top heights. The reanalysis also displays a higher percentage of soundings without inversion, particularly at high latitudes associated with colder sea surface temperature.
INTERNATIONAL JOURNAL OF CLIMATOLOGY
(2022)
Article
Meteorology & Atmospheric Sciences
Wenhui Zhao, Yi Huang, Steven Siems, Michael Manton
Summary: This study characterizes cloud properties associated with precipitation in the region around the Great Barrier Reef (GBR) using satellite observations. The study finds that different cloud types are observed over different regions and vary by season. Additionally, it is found that low-level clouds over the GBR do not show any significant response to the reef-related microphysical perturbations.
INTERNATIONAL JOURNAL OF CLIMATOLOGY
(2022)
Article
Meteorology & Atmospheric Sciences
Artur Gevorgyan, Luis Ackermann, Yi Huang, Steven Siems, Michael Manton
Summary: This study examines a heavy precipitation event associated with a cold front over the Australian Snowy Mountains (ASM) on 3 August 2018 using observational data and high-resolution simulation. The results show that snow growth during the prefrontal period is mainly driven by aggregation and deposition, while graupel production is enhanced during the cold front and postfrontal periods through riming processes.
MONTHLY WEATHER REVIEW
(2022)
Review
Environmental Studies
Steven T. Siems, Yi Huang, Michael J. Manton
Summary: There are large differences between current precipitation products over the Southern Ocean, limiting our understanding of hydrological and climatological processes. The lack of long-term surface observational records contributes to this uncertainty. New resources, such as dual-polarized radars and maritime disdrometers, may help improve the evaluation of precipitation products.
WILEY INTERDISCIPLINARY REVIEWS-CLIMATE CHANGE
(2022)
Article
Meteorology & Atmospheric Sciences
E. Montoya Duque, Y. Huang, S. T. Siems, P. T. May, A. Protat, G. M. McFarquhar
Summary: This study investigates and characterizes cloud and precipitation processes in the Southern Ocean using shipborne observations. The research identifies different cloud and precipitation regimes and diverse microphysical features, and suggests distinct physical processes in different regions of the Southern Ocean.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2022)
Article
Meteorology & Atmospheric Sciences
Branislava Jovanovic, Robert Smalley, Steven Siems
Summary: This study analyzed monthly humidity data from airborne stations in Australia to investigate trends in dew point temperature over a period of 1965-2017. The findings showed an overall increase in humidity over time, with adjusted data indicating smaller linear trends compared to unadjusted data. The study also observed that the increase in humidity is consistent with the expectation that warmer troposphere leads to higher moisture levels.
JOURNAL OF SOUTHERN HEMISPHERE EARTH SYSTEMS SCIENCE
(2023)
Article
Meteorology & Atmospheric Sciences
S. C. H. Truong, S. T. Siems, P. T. May, Y. Huang, E. Vignon, A. Gevorgyan
Summary: Shipborne observations from the CAPRICORN-2018 field campaign were used to investigate the characteristics and variability of precipitation during different periods of an extra-tropical cyclone in the Southern Ocean. The study found that rain was the dominant form of precipitation during the frontal period, while the cyclone period had the highest precipitation with a combination of snow, mixed-phase, and rain. Cold air advection was identified as the main cause of high precipitation during the cyclone period.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2023)
Article
Meteorology & Atmospheric Sciences
Daniel Robbins, Caroline Poulsen, Steven Siems, Simon Proud
Summary: Cloud masking is an important step in retrieving geophysical properties from satellite data. This paper presents a cloud mask created using machine learning for Himawari-8 and compares its performance to other methods. The results show that the machine learning-based cloud mask performs better in identifying non-cloud pixels and distinguishing thick aerosol plumes from clouds.
ATMOSPHERIC MEASUREMENT TECHNIQUES
(2022)
Article
Environmental Sciences
Francisco Lang, Luis Ackermann, Yi Huang, Son C. H. Truong, Steven T. Siems, Michael J. Manton
Summary: This study analyzed the structure and distribution characteristics of marine atmospheric boundary layer clouds in the Southern Ocean using satellite observations. The results showed that closed and open cellular convection have different distributions, with closed MCCs mainly located in the southeast Indian Ocean and along the storm track. Both closed and open MCCs are commonly found in post-frontal, cold air masses, with closed MCCs exhibiting a pronounced daily cycle while open MCCs have almost no diurnal cycle.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2022)