Article
Meteorology & Atmospheric Sciences
Jie Jiang, Yuqing Wang
Summary: This study examines the instability and nonlinear evolution of TC-like vortices with different degrees of hollowness in the eyewall, as well as the influence of the beta effect on the vortex structure. The results show that the eyewalls evolve similarly to those in the nondivergent barotropic model, and the polygonal eyewall structure can be explained by wave-wave interactions of vortex Rossby waves. It is also found that the beta effect can erode the coherent structure of mesovortices in the eyewall, leading to earlier breakdown and axisymmetrization processes.
ADVANCES IN ATMOSPHERIC SCIENCES
(2022)
Article
Geosciences, Multidisciplinary
Huaning Dai, Kun Zhao, Qingqing Li, Wen-Chau Lee, Jie Ming, Ang Zhou, Xueqi Fan, Zhengwei Yang, Feng Zheng, Yihong Duan
Summary: Typhoon Lekima before landing in eastern China exhibited a double-eyewall structure, with the outer eyewall showing quasi-periodic convective strengthening. Various physical mechanisms causing asymmetries in eyewall convection were examined, with phase locking between different vortex waves contributing to pronounced quasi-periodic intensification in the western semicircle of the outer eyewall.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Meteorology & Atmospheric Sciences
Kyle Ahern, Robert E. Hart, Mark A. Bourassa
Summary: In this second part of the study, a simulation of Hurricane Earl in 2010 is used to analyze the cylindrical structure of the lowest 2.5 km of the atmosphere, which includes the boundary layer. During secondary eyewall formation in Hurricane Earl, wind and thermal fields exhibited substantial azimuthal structure, which was found to be important to the formation of the secondary eyewall. This study provides motivation for further investigation of the lower-atmospheric azimuthal structure of hurricanes in relation to storm intensity.
MONTHLY WEATHER REVIEW
(2022)
Article
Meteorology & Atmospheric Sciences
Xingbao Wang, Fuzhong Weng, Wenwu Peng, Hongjie Zhang, Qinglan Li
Summary: Depicting Secondary Eyewall Formation (SEF) and Eyewall Replacement Cycle (ERC) in a numerical model is important for tropical cyclone (TC) forecasting. The impact of horizontal and vertical resolutions on SEF/ERC is examined through numerical experiments. Results show that SEF/ERC is manifested when the horizontal grid spacing is 2-km or smaller, while no obvious SEF/ERC is observed with grid spacings of 6-km and 4-km.
JOURNAL OF ADVANCES IN MODELING EARTH SYSTEMS
(2023)
Article
Meteorology & Atmospheric Sciences
Chau-Lam Yu, Anthony C. Didlake, Fuqing Zhang
Summary: This study investigates the emergence and maintenance of an asymmetric rainband updraft region that leads to secondary eyewall formation. The results show that the maintenance of the left-of-shear updraft is aided by a mesoscale cold pool induced by rainband stratiform cooling and an extended period of destabilization occurs through differential horizontal advection of equivalent potential temperature. Buoyancy advection resulting from the density contrast between the surface cold pool and the inner-core high-theta(E) air leads to the initial lifting of the updraft. Potential vorticity budget analysis reveals that these updrafts generate low- to midlevel PV through diabatic heating and boundary layer processes.
JOURNAL OF THE ATMOSPHERIC SCIENCES
(2022)
Article
Mechanics
Naifu Peng, Yue Yang, Jinxin Wu, Zuoli Xiao
Summary: In this study, the impact of secondary baroclinic vorticity (SBV) on Richtmyer-Meshkov instability (RMI) accelerated by a weak incident shock is elucidated and a vortex-based model for spike and bubble growth rates is developed. Two major mechanisms of single-mode RMI, primary baroclinic vorticity (PBV) and pressure perturbation, are distinguished and it is found that pressure perturbation can be neglected in the current RMI, with growth primarily driven by PBV. Subsequently, SBV leads to nonlinear growth of the interface with the generation of spikes and bubbles.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Meteorology & Atmospheric Sciences
Chau-Lam Yu, Anthony C. Didlake, Fuqing Zhang, Robert G. Nystrom
Summary: The study examines the dynamics of an asymmetric rainband complex leading into secondary eyewall formation in Hurricane Matthew, revealing an axisymmetric acceleration pattern and a mesoscale descending inflow phenomenon.
JOURNAL OF THE ATMOSPHERIC SCIENCES
(2021)
Article
Geosciences, Multidisciplinary
Xinhang Liu, Qingqing Li, Yufan Dai
Summary: Idealized numerical experiments demonstrate that stronger shear is more favorable for the formation of tropical cyclone secondary eyewall (SEF) in a moist-tropical environment. The larger the shear, the earlier the SEF occurs. A stationary banding complex (SBC) exists before SEF in experiments with larger shear, indicating that SBCs are beneficial for SEF. Additionally, a well-organized stratiform sector is associated with the SBC. With increasing shear, the shear-forced outflow increases in the upper layers, leading to the transportation of more moisture and icy particles from the inner core and promoting the development of the stratiform sector. The diabatic cooling of the stratiform sector strengthens the underlying descending radial inflow, resulting in updrafts immediately outside the inner core. The subsequent axisymmetrization of the updrafts leads to SEF.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Meteorology & Atmospheric Sciences
Rong Fang, Shumin Chen, Mingsen Zhou, Weibiao Li, Hui Xiao, Tang Zhan, Yusi Wu, Haoya Liu, Chaoyong Tu
Summary: Recent improvements in forecasting tropical cyclone intensity have been partially hampered by inadequate understanding of eyewall convection processes. This study identified four short-term periodic cycles in eyewall convection, each associated with different rates of intensification in the tropical cyclone. Vertical transport of latent heat played a key role in determining the intensity evolution of the cyclone.
ADVANCES IN METEOROLOGY
(2021)
Article
Meteorology & Atmospheric Sciences
Yi-Fan Wang, Bolei Yang, Zhe-Min Tan
Summary: Recent studies have shown that the formation of outer rainbands is crucial for the secondary eyewall formation of tropical cyclones. This study reveals that cloud-radiation feedback plays a significant role in promoting the formation of outer rainbands and their stratiform sectors, ultimately facilitating the secondary eyewall formation. The cloud-radiation feedback induces upper-level anomalous radiative warming, which triggers a secondary circulation and accelerates the release of microphysical heating, leading to the development of outer rainbands.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2023)
Article
Mechanics
Hongyi Jiang
Summary: This study identifies and explains the formation mechanisms of secondary vortex street in the far wake of a circular cylinder for different Reynolds numbers. It demonstrates that both hydrodynamic instability of the mean flow and merging of layered vortices play a role in the formation, with their dominance depending on the Reynolds number. The variation in streamwise locations for the emergence of secondary vortices with Reynolds number is quantified and explained.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Meteorology & Atmospheric Sciences
Tsz-Kin Lai, Eric A. Hendricks, M. K. Yau, Konstantinos Menelaou
Summary: This study explores the dynamics behind the evolution of the inner and outer eyewalls of tropical cyclones, emphasizing the importance of type-2 barotropic instability (BI) in influencing the inner eyewall decay. Nonlinear experiments show changes in angular momentum over the inner and outer eyewalls, originating solely from the eddy radial transport of eddy angular momentum, highlighting the significance of the nonlinearity of type-2 BI.
JOURNAL OF THE ATMOSPHERIC SCIENCES
(2021)
Article
Geochemistry & Geophysics
Cheng XiaoPing, Fei JianFang, Li XiangCheng, Huang XiaoGang, Yang Wen
Summary: This article discusses the formation and evolution mechanisms of typhoon secondary eyewall, reviews the research progress in this area over the past decade, focuses on the statistical characteristics of domestic and foreign research, and discusses the problems and development directions that need to be addressed in the future.
CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION
(2021)
Article
Meteorology & Atmospheric Sciences
Tsz-Kin Lai, Eric A. Hendricks, Konstantinos Menelaou, M. K. Yau
Summary: Research demonstrates that in double-eyewall tropical cyclones, the type-2 instability may lead to the decay of the inner eyewall and intensification of the outer eyewall. Changes in absolute angular momentum advection induced by this instability significantly affect the intensity of the inner eyewall. Additionally, the type-2 instability can accelerate the decay of the inner eyewall.
JOURNAL OF THE ATMOSPHERIC SCIENCES
(2021)
Article
Mechanics
A. G. Kudryavtsev, N. N. Myagkov
Summary: New exact solutions for describing Rossby waves and vortices in ocean propagating along the zonal direction have been found. These solutions are a partial superposition of previously discovered exact solutions and offer the potential to accurately simulate a wide range of fluid flows.
Article
Meteorology & Atmospheric Sciences
Jian-Feng Gu, Zhe-Min Tan, Xin Qiu
JOURNAL OF THE ATMOSPHERIC SCIENCES
(2015)
Article
Meteorology & Atmospheric Sciences
Jian-Feng Gu, Zhe-Min Tan, Xin Qiu
JOURNAL OF THE ATMOSPHERIC SCIENCES
(2016)
Article
Meteorology & Atmospheric Sciences
Xin Qiu, Zhe-Min Tan
JOURNAL OF THE ATMOSPHERIC SCIENCES
(2013)
Article
Meteorology & Atmospheric Sciences
Jian-Feng Gu, Zhe-Min Tan, Xin Qiu
JOURNAL OF THE ATMOSPHERIC SCIENCES
(2018)
Article
Meteorology & Atmospheric Sciences
Xin Qiu, Qingnong Xiao, Zhe-Min Tan, John Michalakes
QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY
(2011)
Article
Meteorology & Atmospheric Sciences
Jian-Feng Gu, Zhe-Min Tan, Xin Qiu
JOURNAL OF THE ATMOSPHERIC SCIENCES
(2019)
Article
Meteorology & Atmospheric Sciences
Gu-Feng Bian, Gao-Zhen Nie, Xin Qiu
Summary: Multiple reanalysis datasets and observation data were used to analyze the outer size of tropical cyclones, with ERA5 showing improvements in describing TC outer wind fields and size, especially in the eastern North Pacific basin. However, ERA5 still tends to underestimate the outer size, with the radius of 9 m/s winds considered the optimal metric for studying the extent of outer winds.
ATMOSPHERIC RESEARCH
(2021)