23 research outputs found
Sq and EEJ—A Review on the Daily Variation of the Geomagnetic Field Caused by Ionospheric Dynamo Currents
A record of the geomagnetic field on the ground sometimes shows smooth daily variations on the order of a few tens of nano teslas. These daily variations, commonly known as Sq, are caused by electric currents of several μA/m^2 flowing on the sunlit side of the E-region ionosphere at about 90–150 km heights. We review advances in our understanding of the geomagnetic daily variation and its source ionospheric currents during the past 75 years. Observations and existing theories are first outlined as background knowledge for the non-specialist. Data analysis methods, such as spherical harmonic analysis, are then described in detail. Various aspects of the geomagnetic daily variation are discussed and interpreted using these results. Finally, remaining issues are highlighted to provide possible directions for future work
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Recommendations on simple but transformative diversity, equity, and inclusion measures in Heliophysics over the next decade
It is well established that, in order to perform at their peak ability, a person must feel accepted, safe, and valued at work. Therefore, it is imperative to bring Diversity, Equity, and Inclusion (DEI) efforts to the forefront of Heliophysics over the next decade and well beyond. This position paper outlines three specific recommendations to make the Heliophysics community more diverse, equitable, and inclusive by improving the accessibility and accountability. These recommendations are: performing consistent collection and analysis of demographic data across different agencies, reimagining undergraduate Heliophysics internships using the SOARS® model, and providing conference funding for DEI speakers whose expertise lies outside the field of Heliophysics. These targeted recommendations have a well-documented positive impact, are simple to implement, and follow other scientific communities’ recent recommendations for making the science, technology, engineering, and mathematics fields more diverse, equitable, and inclusive
Inter-hemispheric asymmetries in high-latitude electrodynamic forcing and the thermosphere during the October 8–9, 2012, geomagnetic storm: An integrated data–Model investigation
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 By dependence 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
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Thoughts from a past AGU SPA fellows committee
Community honours, such as those bestowed by professional scientific societies like the American Geophysical Union (AGU) are an important element of both individual career advancement and contributes to the historical record of scientific progress. The process by which honours are bestowed is not widely shared amongst the community. The purpose of this article is to share the recent experiences of several members of the AGU Space Physics and Aeronomy (SPA) Fellows committee. We outline the criteria for selection, the evaluation process, difficulties encountered by the committee, and steps taken to mitigate these difficulties. Of particular note is the impact of implicit bias in the award system. Steps could be taken by the awarding scientific societies to reduce the impact of these biases, but in the meantime individual award committees can employ some of the strategies we outline in this article. By sharing our experiences, we hope to improve the process of granting awards and honours for the scientists putting together award nominations, future committee members, and the scientific societies granting these awards.
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Next generation magnetic field measurements from low-earth orbit satellites enable enhanced space weather operations
Large-scale current systems in the ionosphere and the magnetosphere are intimately controlled by the solar wind-magnetosphere interaction and the magnetosphere-ionosphere coupling. During space weather events, these currents reconfigure and intensify significantly in response to enhanced solar wind-magnetosphere interaction, facilitating explosive energy input from the magnetosphere into the ionosphere-thermosphere system and inducing electric current surges in electric power systems on the ground. Therefore, measurements of magnetic manifestations associated with the dynamic changes of the current systems are crucial for specifying the energy input into the ionosphere-thermosphere system, understanding energy dissipation mechanisms, and predicting the severity of their space weather impacts. We investigate the potential uses of high-quality magnetic field data for space weather operations and propose real-time data products from next generation constellation missions that enable improved space weather forecasting and mitigation.
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Plasma-neutral interactions in the lower thermosphere-ionosphere : The need for in situ measurements to address focused questions
The lower thermosphere-ionosphere (LTI) is a key transition region between Earth's atmosphere and space. Interactions between ions and neutrals maximize within the LTI and in particular at altitudes from 100 to 200 km, which is the least visited region of the near-Earth environment. The lack of in situ co-temporal and co-spatial measurements of all relevant parameters and their elusiveness to most remote-sensing methods means that the complex interactions between its neutral and charged constituents remain poorly characterized to this date. This lack of measurements, together with the ambiguity in the quantification of key processes in the 100-200 km altitude range affect current modeling efforts to expand atmospheric models upward to include the LTI and limit current space weather prediction capabilities. We present focused questions in the LTI that are related to the complex interactions between its neutral and charged constituents. These questions concern core physical processes that govern the energetics, dynamics, and chemistry of the LTI and need to be addressed as fundamental and long-standing questions in this critically unexplored boundary region. We also outline the range of in situ measurements that are needed to unambiguously quantify key LTI processes within this region, and present elements of an in situ concept based on past proposed mission concepts.Peer reviewe
Thank You to Our 2023 Reviewers
The Editors and Staff of Earth and Space Science thank the reviewers whose selfless work has significantly contributed to the publication process of papers highlighting the best research in geophysics, planetary, and space science in 2023. Peer-reviewing is a demanding and thankless job. It is however an essential component of the scientific process, requiring the highest standards of integrity and rigor. Reviewers check data and procedures and test reproducibility of methods and results; they share their expertise to verify that the interpretations and conclusions of a paper are consistent with assumptions and existing knowledge. Without this essential work it would not be possible to trust in the scientific process. Publication of papers in a multidisciplinary journal such as Earth and Space Science, that highlights methods, instruments, data and algorithms, relies directly on the expertise of its reviewers to verify and vouch for the quality of the papers that are published. We are indebted to all our reviewers and are delighted to acknowledge them publicly in this Editorial
Cultivating a culture of inclusivity in heliophysics
A large number of heliophysicists from across career levels, institution types, and job titles came together to support a poster at Heliophysics 2050 and the position papers for the 2024 Heliophysics decadal survey titled “Cultivating a Culture of Inclusivity in Heliophysics,” “The Importance of Policies: It’s not just a pipeline problem,” and “Mentorship within Heliophysics.” While writing these position papers, the number of people who privately shared disturbing stories and experiences of bullying and harassment was shocking. The number of people who privately expressed how burned out they were was staggering. The number of people who privately spoke about how they considered leaving the field for their and their family’s health was astounding. And for as much good there is in our community, it is still a toxic environment for many. If we fail to do something now, our field will continue to suffer. While acknowledging the ongoing growth that we as individuals must work toward, we call on our colleagues to join us in working on organizational, group, and personal levels toward a truly inclusive culture, for the wellbeing of our colleagues and the success of our field. This work includes policies, processes, and commitments to promote: accountability for bad actors; financial security through removing the constant anxiety about funding; prioritization of mental health and community through removing constant deadlines and constant last-minute requests; a collaborative culture rather than a hyper-competitive one; and a community where people can thrive as whole persons and do not have to give up a healthy or well-rounded life to succeed
Table1_Assessing the demographics of the 2021 and 2022 CEDAR workshop.XLSX
The Coupling, Energetics and Dynamics of Atmospheric Regions (CEDAR) community is made of engineers, scientists, physicists, and students with a mission to understand the fundamental properties and predictability of the space-atmosphere interaction region, including the mesosphere, thermosphere, ionosphere, and inner magnetosphere. At the 2020 CEDAR annual workshop, community-wide feedback received on diversity, equity, and inclusion (DEI) in CEDAR warranted a grassroots effort focused on addressing the DEI issues raised. This led to the creation of the CEDAR DEI task force, whose goals were to 1) Assess and formalize DEI efforts in CEDAR; 2) Establish and normalize a DEI presence in the CEDAR community; and 3) Foster improvement in CEDAR through implementation of actionable initiatives that promote diversity, equity, and inclusion. Of these actionable items collecting demographic information on those participating in the Annual CEDAR Workshop was identified as the top priority. This paper therefore, reports the demographic information obtained from CEDAR registrants for the virtual workshop in 2021 and in-person workshop in 2022. In general, the demographics of CEDAR are consistent with those in broader science, technology, engineering, and mathematics (STEM) fields, that is, most participants identify as male, White, and or Asian/Middle Eastern. On average, women and historically underrepresented races and ethnicities in STEM fields make up roughly 30% and 10%, respectively, of all 2021 and 2022 CEDAR Workshop registrants over the past 2Â years. We further discuss the demographics of CEDAR relative to reports published in recent years by other organizations, where possible.</p
DataSheet1_Assessing the demographics of the 2021 and 2022 CEDAR workshop.PDF
The Coupling, Energetics and Dynamics of Atmospheric Regions (CEDAR) community is made of engineers, scientists, physicists, and students with a mission to understand the fundamental properties and predictability of the space-atmosphere interaction region, including the mesosphere, thermosphere, ionosphere, and inner magnetosphere. At the 2020 CEDAR annual workshop, community-wide feedback received on diversity, equity, and inclusion (DEI) in CEDAR warranted a grassroots effort focused on addressing the DEI issues raised. This led to the creation of the CEDAR DEI task force, whose goals were to 1) Assess and formalize DEI efforts in CEDAR; 2) Establish and normalize a DEI presence in the CEDAR community; and 3) Foster improvement in CEDAR through implementation of actionable initiatives that promote diversity, equity, and inclusion. Of these actionable items collecting demographic information on those participating in the Annual CEDAR Workshop was identified as the top priority. This paper therefore, reports the demographic information obtained from CEDAR registrants for the virtual workshop in 2021 and in-person workshop in 2022. In general, the demographics of CEDAR are consistent with those in broader science, technology, engineering, and mathematics (STEM) fields, that is, most participants identify as male, White, and or Asian/Middle Eastern. On average, women and historically underrepresented races and ethnicities in STEM fields make up roughly 30% and 10%, respectively, of all 2021 and 2022 CEDAR Workshop registrants over the past 2Â years. We further discuss the demographics of CEDAR relative to reports published in recent years by other organizations, where possible.</p