LWS TR&T Focus Teams:
Determine the sources of daily variability in the thermosphere and ionosphere
Team Chair: Stanley Solomon
Target Description: Understanding the day-to-day variability of the ionosphere and thermosphere remains an outstanding problem. It is a key to unraveling the relative strengths of two primary forcing mechanisms of the I-T system: photon-driven versus particle/plasma driven solar energy input changes. The responses of the I-T system to each mechanism are strongly inhomogeneous, depending for example, on altitude and geographical location (photons are input primarily at low-mid latitudes whereas geomagnetic effects commence at higher latitudes and propagate to lower latitudes). Forcing from below must be considered also. Understanding inter-day variability will improve space weather predictions under nominal conditions. It will also improve storm-time predictions by providing an accurate baseline prior to the initiation of geomagnetic disturbances.
measures of success:The goal of this topic is improved understanding of the observed day-to-day variability of the ionosphere-thermosphere including thermospheric densities, composition, winds, and ionospheric electron densities. Successful investigations will use observations and modeling to quantify the causes of variability. Improved predictive models of short-term space weather effects are an expected outcome. Multi-disciplinary perspectives are especially encouraged that account for temporal variability of the drivers such as solar photons and the solar wind.
Types of solicited investigations: We solicit empirical characterizations of day-to-day variability using recent data and observational methods. Observations, models and combinations that identify the relative roles of solar forcing and internal dynamics in creating observed daily variability. Multi-disciplinary investigations that characterize how the broader heliospheric environment affects daily variability are especially encouraged.