10 research outputs found

    Polar Topside Ionosphere During Geomagnetic Storms: Comparison of ISIS-II With TDIM

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    Space weather deposits energy into the high polar latitudes, primarily via Joule heating that is associated with the Poynting flux electromagnetic energy flow between the magnetosphere and ionosphere. One way to observe this energy flow is to look at the ionospheric electron density profile (EDP), especially that of the topside. The altitude location of the ionospheric peak provides additional information on the net field‐aligned vertical transport at high latitudes. To date, there have been few studies in which physics‐based ionospheric model storm simulations have been compared with topside EDPs. A rich database of high‐latitude topside ionograms obtained from polar orbiting satellites of the International Satellites for Ionospheric Studies (ISIS) program exists but has not been utilized in comparisons with physics‐based models. Of specific importance is that the Alouette/ISIS topside EDPs spanned the timeframe from 1962 to 1983, a period that experienced very large geomagnetic storms. We use a physics‐based ionospheric model, the Utah State University Time Dependent Ionospheric Model (TDIM), to simulate ionospheric EDPs for quiet and storm high‐latitude passes of ISIS‐II for two geomagnetic storms. This initial study finds that under quiet conditions there is good agreement between model and observations. During disturbed conditions, however, a large difference is seen between model and observations. The model limitation is probably associated with the inability of its topside boundary to replicate strong outflow conditions. As a result, modeling of the ionospheric outflows needs to be extended well into the magnetosphere, thereby moving the upper boundary much higher and requiring the use of polar wind models

    The Youngest Victims: Children and Youth Affected by War

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    In 1989, the United Nation Convention on the Rights of the Child declared, “[state parties] shall take all feasible measures to ensure protection and care of children who are affected by an armed conflict.” In addition to attempting to secure the welfare of children in armed conflict, the Convention went on to ban the recruitment and deployment of children during armed conflict. Despite the vast majority of sovereign nations signing and ratifying this agreement, this treaty, unfortunately, has not prevented children and youth from witnessing, becoming victims of, or participating in political, ethnic, religious, and cultural violence across the past three decades. This chapter offers an “ecological perspective” on the psychosocial consequences of exposure to the trauma of war-related violence and social disruption

    Ionospheric Plasma Bubble Zonal Velocities From Christmas Island Using Airglow Emissions

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    Night-time equatorial F region plasma irregularities (depletions) can significantly affect low-latitude communications and navigation systems. Deep plasma depletions referred to as plasma bubbles, can rise through the F region peak up to the topside ionosphere to about 1500 km. The variability in the occurrence and intensity of equatorial plasma bubbles constitutes an important problem in the study of the space weather. Air Force Communication/Navigation Outage Forecasting System (C/NOFS) satellite is used to quantify and forecast ionospheric irregularities responsible for the development of equatorial spread F (ESF). The plasma depletion zonal velocity is a very important parameter for the understanding and modeling of the electrodynamics of the equatorial ionosphere and for the predictions of ionospheric scintillations

    Development of a Multimodel Ensemble Prediction System to Specify Ionospheric Weather

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    Reviews the development of a multimode space weather system. The system assimilates a range of ionospheric, electrodynamic and thermospheric data models

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