A model providing long‐term data sets of energetic electron precipitation during geomagnetic storms

Abstract

The influence of solar variability on the polar atmosphere and climate due to energetic electron precipitation (EEP) has remained an open question largely due to lack of a long-term EEP forcing data set that could be used in chemistry-climate models. Motivated by this, we have developed a model for 30-1000 keV radiation belt driven EEP. The model is based on precipitation data from low Earth orbiting POES satellites in the period 2002-2012 and empirically described plasmasphere structure, which are both scaled to a geomagnetic index. This geomagnetic index is the only input of the model and can be either Dst or Ap. Because of this, the model can be used to calculate the energy-flux spectrum of precipitating electrons from 1957 (Dst) or 1932 (Ap) onward, with a time resolution of 1 day. Results from the model compare well with EEP observations over the period of 2002-2012. Using the model avoids the challenges found in measured data sets concerning proton contamination. As demonstrated, the model results can be used to produce the first ever >80 year long atmospheric ionization rate data set for radiation belt EEP. The impact of precipitation in this energy range is mainly seen at altitudes 70-110 km. The ionization rate data set, which is available for the scientific community, will enable simulations of EEP impacts on the atmosphere and climate with realistic EEP variability. Due to limitations in this first version of the model, the results most likely represent an underestimation of the total EEP effect.

Observations and Modeling of Increased Nitric Oxide in the Antarctic Polar Middle Atmosphere Associated With Geomagnetic Storm‐Driven Energetic Electron Precipitation

“…The differences between the two WACCM-SIC runs are very similar to those reported for WACCM simulations over decadal timescales (Andersson et al, 2018) in which 30-1,000 keV EEP was introduced using an Ap index-driven model (van de Kamp et al, 2016), rather than the electron observation-based estimates of MEE ionization used in this study. The SOFIE observations and WACCM-SIC simulation results are compared in Figure 9, which shows NO number density at 10 km intervals from 60 to 110 km after applying a 31-day moving average to each of the three data sets.…”

“…The methodology for calculating MEE ionization rates was similar to that described in Orsolini et al (2018). This method is based on direct satellite measurements by the MEPED instrument rather than the proxy-based parameterizations (e.g., Matthes et al, 2017;van de Kamp et al, 2016) developed as part of the long-term solar forcing data set recommended for the sixth phase of the Coupled Model Intercomparison Project (CMIP6). However, different from Orsolini et al (2018), we changed the energy range from 50-2,000 keV to 30-1,000 keV to be consistent with the CMIP6 recommendation.…”

Space Weather Effects in the Earth’s Radiation Belts

“…For example, the AIMOS model uses statistical maps of precipitation, scaled with observed electron fluxes to provide global RBE (and other EPP) forcing data from year 2002 onwards (Wissing and Kallenrode 2009). Recently, a RBE model driven by geomagnetic indices has been created for multi-decadal climate simulations (Van de Kamp et al 2016) as a part of the solar forcing recommendation for Coupled Model Intercomparison Project Phase 6 (CMIP6) (Matthes 2016). An example of the model output, in Fig.…”

“…It connects ozone and dynamical changes in the stratosphere to modulation of the North Atlantic Oscillation, which is a large-scale mode (i.e., pattern) Fig. 41 Yearly average, zonal mean mesospheric ionization rates due to RBE, calculated using the model by Van de Kamp et al (2016). The model provides data at L shells 2 to 10, white areas indicate no data of climate variability around the North Atlantic.…”

Development of low power wireless fluxgate magnetometer instrumentation for real-time geomagnetic monitoring

“…Satellite operation is strongly dictated by near-Earth orbit space weather condition [8]. At Earth's high latitude region, geomagnetic storm can cause the phenomena called "the northern lights" or aurora borealis [9]. The modern space physics human knowledge is intimately linked to development of magnetic field instrumentation and its ability [10].…”