Article
Astronomy & Astrophysics
Raphael Hardy, Andrew Cumming, Paul Charbonneau
Summary: The atmosphere of a hot Jupiter may experience a thermoresistive instability due to the increasing electrical conductivity with temperature. This instability leads to uncontrolled ohmic heating. A simplified model is introduced to describe the local dynamics of the equatorial region of a hot Jupiter, considering the back reaction on the atmospheric flow as the electrical conductivity increases. The model shows periodic bursts of Alfven oscillations separated by quiescent intervals, with the magnetic Reynolds number alternating between values smaller than and larger than unity, maintaining the oscillation. This instability operates at pressures of 0.1-1 bar and temperatures of 1300-1800 K for magnetic fields of 10 G, showing stronger instability for weaker magnetic fields.
ASTROPHYSICAL JOURNAL
(2022)
Article
Meteorology & Atmospheric Sciences
Alice Portal, Claudia Pasquero, Fabio D'Andrea, Paolo Davini, Mostafa E. Hamouda, Gwendal Riviere
Summary: This study investigates the impact of weakened winter land-sea thermal contrast on the extratropical circulation in the Northern Hemisphere. The results show that the reduction of land-sea thermal contrast leads to a weakening and poleward shift of the midlatitude jet streams and strong interference with zonal wavenumbers 1 and 2. The warming in East Asia reduces the amplitude of waves 1 and 2, resulting in a strengthening of the stratospheric vortex, while warming in North America weakens the vortex due to a moderate amplification of wave 1. The stratospheric signals eventually propagate downward, affecting the midlatitude winter NH even remotely from the forcing.
JOURNAL OF CLIMATE
(2022)
Article
Chemistry, Multidisciplinary
Uladzislau Makartsou, Mathieu Moalic, Mateusz Zelent, Michal Mruczkiewicz, Maciej Krawczyk
Summary: This paper demonstrates the control of chirality in a symmetrical ferromagnetic nanoring by breaking the circular symmetry of the system through the placement of an elongated ferromagnetic nanoelement inside the ring.
Article
Meteorology & Atmospheric Sciences
Pengfei Zhang, Gang Chen, Yi Ming
Summary: This study provides a new analysis on the circulation response to increasing CO2 concentration in an aquaplanet atmospheric model. The results show that the zonal advection feedback plays a significant role in changes to the eddy-driven jet shift and Hadley cell expansion, contributing to the subtropical precipitation decline. The study highlights the distinct effect of zonal mean advecting wind and direct thermodynamic effects in atmospheric response to greenhouse gas increases.
JOURNAL OF CLIMATE
(2021)
Article
Geosciences, Multidisciplinary
S. V. S. Brand, C. J. Prend, L. D. Talley
Summary: Much of the salty, high oxygen North Atlantic Deep Water (NADW) leaving the Atlantic flows through the Argentine Basin, where it is diluted by fresher, low oxygen Circumpolar Deep Water (CDW). This mixing of deep water masses is often overlooked in the zonally averaged description of the overturning circulation. Here, we show that intense mixing occurs along the western boundary: (a) extreme, isolated oxygen/temperature anomalies recorded by three autonomous biogeochemical floats suggest that subsurface eddies can inject relatively unmodified CDW far into the northwestern Argentine Basin, and (b) moderate, numerous temperature/salinity anomalies indicate a mixing zone from Rio Grande Rise to the Malvinas Current. This western eddy pathway shortcuts the gyre-scale cyclonic route for CDW inferred from most previous studies. Significantly, CDW dilution of NADW affects the properties of deep waters that upwell in the Southern Ocean, and hence the connection between Northern and Southern Hemisphere polar climates.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Environmental Sciences
Daisuke Hirano, Kohei Mizobata, Hiroko Sasaki, Hiroto Murase, Takeshi Tamura, Shigeru Aoki
Summary: Comprehensive hydrographic observations suggest that Circumpolar Deep Water is efficiently transported towards the shelf break off Totten Ice Shelf, East Antarctica by cyclonic eddies. This process may potentially influence the melting of ice underneath the shelf.
COMMUNICATIONS EARTH & ENVIRONMENT
(2021)
Article
Geosciences, Multidisciplinary
Qinbo Xu, Linlin Zhang, Xin Xiao, Chun Zhou, Fan Wang, Dunxin Hu
Summary: This article investigates the seasonal connection between LSDO and DWBC, revealing that the seasonal variation in DWBC influences the LSDO by adjusting the temperature field on the east side of the Luzon Strait.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Oceanography
Henry G. Peterson, Jorn Callies
Summary: The near-bottom mixing in the ocean allows for the upwelling of abyssal waters and affects the flow over midocean ridges. This study extends the commonly used one-dimensional model to capture the spinup and spindown of along-slope flow by considering a two-dimensional approach that includes the effect of Ekman transport and the pressure gradient. The extended model accurately describes the spinup over an idealized ridge and provides a unified framework for understanding the importance of Ekman arrest and spindown in flow along a slope.
JOURNAL OF PHYSICAL OCEANOGRAPHY
(2022)
Article
Geosciences, Multidisciplinary
Pedro Herrera-Lormendez, Herve Douville, Jorg Matschullat
Summary: In 2022, western Europe experienced its hottest summer on record with widespread dry conditions. Circulation anomalies and human-caused greenhouse gas emissions contributed to extreme temperatures and dry days, and future climate change will exacerbate these extremes.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Review
Meteorology & Atmospheric Sciences
Frank J. Pavia, C. Spencer Jones, Sophia K. Hines
Summary: This paper critically assesses the approaches used to determine the geometry of Atlantic circulation during the Last Glacial Maximum (LGM) and provides best practices for future research. The study highlights the complexity of interpreting geochemical proxies as water mass structure due to small-scale mixing processes in the ocean interior. It outlines promising paths for further ascertaining the LGM circulation structure.
JOURNAL OF CLIMATE
(2022)
Article
Mechanics
Zhijie Zhao, Xiong Deng, Zhenbing Luo, Wanbo Wang, Jianyuan Zhang, Zhaofeng Dong
Summary: In this study, the control potential of reverse dual synthetic jets (RDSJs) in a flying wing aircraft (FWA) is investigated using numerical simulations. The results show that the aerodynamic loads follow a nonlinear trend and can be divided into three stages with an increasing angle of attack (AOA). In the first stage, the RDSJs improve the reverse pressure gradients and form alternate recirculation zones. In the second stage, the energy of the RDSJs is too low to form a strong disturbance over the leeward surface. In the third stage, the RDSJs interact with the larger separation and accelerate the flow, improving the strength and stability of the leading-edge vortex (LEV).
Article
Meteorology & Atmospheric Sciences
Marion Saint-Lu, Sandrine Bony, Jean-Louis Dufresne
Summary: This study uses satellite observations, meteorological reanalyses, and climate model simulations to show that variations in the height and spatial extent of tropical anvil clouds can be explained by basic physical arguments related to the conservation of mass and energy in clear-sky areas of the tropics. These findings are important for understanding and assessing the impacts of natural and anthropogenic perturbations on anvil cloud fraction.
NPJ CLIMATE AND ATMOSPHERIC SCIENCE
(2022)
Article
Meteorology & Atmospheric Sciences
David B. Bonan, Andrew F. Thompson, Emily R. Newsom, Shantong Sun, Maria Rugenstein
Summary: This study examines the response of the Atlantic meridional overturning circulation (AMOC) to an abrupt quadrupling of atmospheric carbon dioxide using a collection of GCM simulations. The simulations show consistent weakening of the AMOC during the first century, but diverse behaviors over longer time scales. The study attributes the AMOC behavior to changes in temperature and salinity in different regions, highlighting the importance of considering high-latitude freshwater changes and salinity anomalies for understanding the long-term evolution of the AMOC.
JOURNAL OF CLIMATE
(2022)
Article
Energy & Fuels
Sun Jinsheng, Bai Yingrui, Cheng Rongchao, Lyu Kaihe, Liu Fan, Feng Jie, Lei Shaofei, Zhang Jie, Hao Huijun
Summary: This study summarizes the mechanisms of drilling fluid lost circulation and its control, as well as the applicability and working mechanisms of different types of lost circulation materials in plugging fractured formations. It also analyzes the advantages, disadvantages, and application effects of corresponding plugging technologies to identify key problems in current lost circulation control technologies. The study suggests focusing on five aspects for future research and development to improve lost circulation control technology.
PETROLEUM EXPLORATION AND DEVELOPMENT
(2021)
Article
Meteorology & Atmospheric Sciences
Fabio Boeira Dias, Catia M. Domingues, Simon J. Marsland, Stephen R. Rintoul, Petteri Uotila, Russell Fiedler, Mauricio M. Mata, Nathaniel L. Bindoff, Abhishek Savita
Summary: The study highlights the influence of surface wind perturbations on the response of the Antarctic subpolar Southern Ocean, leading to enhanced Antarctic Bottom Water formation and accelerated global Meridional Overturning Circulation. Open Water Polynya (OWP) events are triggered by upwelling warm waters and inhibition of sea ice growth, with their availability linked to deep ocean heat reservoirs.
JOURNAL OF CLIMATE
(2021)
