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Inter-hemispheric asymmetry (IHA) in Earth’s ionosphere–thermosphere (IT) system can be associated with high-latitude forcing that intensifies during storm time, e.g., ion convection, auroral electron precipitation, and energy deposition, but a comprehensive understanding of the pathways that generate IHA in the IT is lacking. Numerical simulations can help address this issue, but accurate specification of high-latitude forcing is needed. In this study, we utilize the Active Magnetosphere and Planetary Electrodynamics Response Experiment-revised fieldaligned currents (FACs) to specify the high-latitude electric potential in the Global Ionosphere and Thermosphere Model (GITM) during the October 8–9, 2012, storm. Our result illustrates the advantages of the FAC-driven technique in capturing high-latitude ion drift, ion convection equatorial boundary, and the storm-time neutral density response observed by satellite. First, it is found that the cross-polar-cap potential, hemispheric power, and ion convection distribution can be highly asymmetric between two hemispheres with a clear B_ydependence in the convection equatorial boundary. Comparison with simulation based on mirror precipitation suggests that the convection distribution is more sensitive to FAC, while its intensity also depends on the ionospheric conductance-related precipitation. Second, the IHA in the neutral density response closely follows the IHA in the total Joule heating dissipation with a time delay. Stronger Joule heating deposited associated with greater high-latitude electric potential in the southern hemisphere during the focus period generates more neutral density as well, which provides some evidences that the high-latitude forcing could become the dominant factor to IHAs in the thermosphere when near the equinox. Our study improves the understanding of storm-time IHA in high-latitude forcing and the IT system.

 

In the space physics community, processing and combining observational and modeling data from various sources is a demanding task because they often have different formats and use different coordinate systems. The Python package GeospaceLAB has been developed to provide a unified, standardized framework to process data. The package is composed of six core modules, including DataHub as the data manager, Visualization for generating publication quality figures, Express for higher-level interfaces of DataHub and Visualization , SpaceCoordinateSystem for coordinate system transformations, Toolbox for various utilities, and Configuration for preferences. The core modules form a standardized framework for downloading, storing, post-processing and visualizing data in space physics. The object-oriented design makes the core modules of GeospaceLAB easy to modify and extend. So far, GeospaceLAB can process more than twenty kinds of data products from nine databases, and the number will increase in the future. The data sources include, e.g., measurements by EISCAT incoherent scatter radars, DMSP, SWARM, and Grace satellites, OMNI solar wind data, and GITM simulations. In addition, the package provides an interface for the users to add their own data products. Hence, researchers can easily collect, combine, and view multiple kinds of data for their work using GeospaceLAB. Combining data from different sources will lead to a better understanding of the physics of the studied phenomena and may lead to new discoveries. GeospaceLAB is an open source software, which is hosted on GitHub. We welcome everyone in the community to contribute to its future development. 

Abstract Aqueous zinc batteries are attracting interest because of their potential for cost-effective and safe electricity storage. However, metallic zinc exhibits only moderate reversibility in aqueous electrolytes. To circumvent this issue, we study aqueous Zn batteries able to form nanometric interphases at the Zn metal/liquid electrolyte interface, composed of an ion-oligomer complex. In Zn||Zn symmetric cell studies, we report highly reversible cycling at high current densities and capacities (e.g., 160 mA cm −2 ; 2.6 mAh cm −2 ). By means of quartz-crystal microbalance, nuclear magnetic resonance, and voltammetry measurements we show that the interphase film exists in a dynamic equilibrium with oligomers dissolved in the electrolyte. The interphase strategy is applied to aqueous Zn||I 2 and Zn||MnO 2 cells that are charged/discharged for 12,000 cycles and 1000 cycles, respectively, at a current density of 160 mA cm −2 and capacity of approximately 0.85 mAh cm −2 . Finally, we demonstrate that Zn||I 2 -carbon pouch cells (9 cm 2 area) cycle stably and deliver a specific energy of 151 Wh/kg (based on the total mass of active materials in the electrode) at a charge current density of 56 mA cm −2 . 

An important question that is being increasingly studied across subdisciplines of Heliophysics is “how do mesoscale phenomena contribute to the global response of the system?” This review paper focuses on this question within two specific but interlinked regions in Near-Earth space: the magnetotail’s transition region to the inner magnetosphere and the ionosphere. There is a concerted effort within the Geospace Environment Modeling (GEM) community to understand the degree to which mesoscale transport in the magnetotail contributes to the global dynamics of magnetic flux transport and dipolarization, particle transport and injections contributing to the storm-time ring current development, and the substorm current wedge. Because the magnetosphere-ionosphere is a tightly coupled system, it is also important to understand how mesoscale transport in the magnetotail impacts auroral precipitation and the global ionospheric system response. Groups within the Coupling, Energetics and Dynamics of Atmospheric Regions Program (CEDAR) community have also been studying how the ionosphere-thermosphere responds to these mesoscale drivers. These specific open questions are part of a larger need to better characterize and quantify mesoscale “messengers” or “conduits” of information—magnetic flux, particle flux, current, and energy—which are key to understanding the global system. After reviewing recent progress and open questions, we suggest datasets that, if developed in the future, will help answer these questions. 

Principles of interfacial chemical kinetics provide powerful guidelines for designing battery anodes.