The link between solar wind structures, geomagnetic indices, and energetic electron precipitation

2020 ◽  
Author(s):  
Josephine Salice ◽  
Hilde Nesse Tyssøy ◽  
Christine Smith-Johansen ◽  
Eldho Midhun Babu
Keyword(s):  
Solar Wind ◽  
Ozone Concentration ◽  
High Speed ◽  
Climate Models ◽  
Middle Atmosphere ◽  
Energetic Electron ◽  
Accurate Estimate ◽  
Electron Precipitation ◽  
Loss Cone ◽  
Accurate Quantification

<p>Energetic electron precipitation (EEP) into the Earth’s atmosphere can collide with gases and deposit their energy there. The collisions between electrons and atmospheric gasses initiate several chemical reactions which can reduce the ozone concentration. Ozone is critically important in the middle atmosphere energy budget as changes in the ozone concentration impact temperature and winds. EEP is not fully understood in terms of how much energy is being deposited and what the associated drivers are.  An accurate quantification of EEP has limitations due to instrumental challenges and therefore imposes limitations of the associated EEP parameterization into climate models. A solution to this problem is a better understanding of the driver processes of energetic electron acceleration and precipitation, alongside optimized measurements. In this study the bounce loss cone fluxes are inferred from EEP measurements by MEPED on board NOAA/POES and EUMETSAT/METOP at tens of keV to relativistic energies. It investigates EEP in contexts of three different solar wind structures: high-speed streams, coronal mass ejections, and ambient or slow interstream solar wind, as well as geomagnetic activity. The study will focus on the year 2010 and aim to understand the context EEP is created in, which will allow a more accurate estimate of the EEP to be applied in atmospheric climate models</p>

Solar wind structures and their effects on energetic electron precipitation

2021 ◽  
Author(s):  
Josephine Alessandra Salice ◽  
Hilde Nesse Tyssøy ◽  
Christine Smith-Johnsen ◽  
Eldho Midhun Babu
Keyword(s):  
Solar Wind ◽  
Ozone Concentration ◽  
High Speed ◽  
Climate Models ◽  
Middle Atmosphere ◽  
Energetic Electron ◽  
Accurate Estimate ◽  
Electron Precipitation ◽  
Loss Cone ◽  
Speed Solar Wind

<p>Energetic electron precipitation (EEP) into the Earth's atmosphere can collide with gases and deposit their energy there. The collisions between electrons and atmospheric gasses initiate several chemical reactions which can reduce the ozone concentration. Ozone is critically important in the middle atmosphere energy budget as changes in the ozone concentration impact temperature and winds. EEP is not fully understood in terms of how much energy is being deposited and what the associated drivers are. An accurate quantification of EEP has limitations due to instrumental challenges and therefore imposes limitations of the associated EEP parameterization into climate models. A solution to this problem is a better understanding of the driver processes of energetic electron acceleration and precipitation, alongside optimized data handling. In this study the bounce loss cone fluxes are inferred from EEP measurements by the Medium Energy Proton and Electron Detector (MEPED) on board the Polar Orbiting Environmental Satellite (POES) and the Meteorological Operational Satellite Program of Europe (METOP) at tens of keV to relativistic energies. It investigates EEP in contexts of different solar wind structures: high-speed solar wind streams (HSSs) and coronal mass ejections (CMEs), during an eleven-year period from 2004 – 2014. While today's chemistry climate models only provide snapshots of EEP, independent of context, this study aims to understand the context EEP is created in, which will allow a more accurate estimate of the EEP to be applied in atmospheric climate models.</p>

Determining latitudinal extent of energetic electron precipitation using MEPED on-board NOAA POES

2020 ◽  
Author(s):  
Eldho Midhun Babu ◽  
Hilde Nesse Tyssøy ◽  
Christine Smith-Johnsen ◽  
Ville Aleksi Maliniemi ◽  
Josephine Alessandra Salice ◽  
...  
Keyword(s):  
Solar Wind ◽  
Radiation Belt ◽  
Climate Models ◽  
Stratospheric Ozone ◽  
Energetic Electron ◽  
Radiation Belts ◽  
Atmospheric Dynamics ◽  
Electron Precipitation ◽  
Atmospheric Effects ◽  
The Earth

<p>Energetic electron precipitation (EEP) from the plasma sheet and the radiation belts, can collide with gases in the atmosphere and deposit their energy. EEP increase the production of NOx and HOx, which will catalytically destroy stratospheric ozone, an important element of atmospheric dynamics. The particle precipitation also causes variation in the radiation belt population. Therefore, measurement of latitudinal extend of the precipitation boundaries is important in quantifying atmospheric effects of Sun-Earth interaction and threats to spacecrafts and astronauts in the Earth’s radiation belt. <br>This study uses measurements by MEPED detectors of six NOAA/POES and EUMETSAT/METOP satellites during the year 2010 to determine the latitudinal boundaries of EEP and its variability with geomagnetic activity and solar wind drivers. Variation of the boundaries with respect to different particle energies and magnetic local time is studied. The result will be a key element for constructing a model of EEP variability to be applied in atmosphere climate models.</p>

Determining latitudinal extent of energetic electron precipitation  using MEPED on-board NOAA POES

2021 ◽  
Author(s):  
Eldho Midhun Babu ◽  
Hilde Nesse Tyssøy ◽  
Christine Smith-Johnsen ◽  
Ville Maliniemi ◽  
Josephine Alessandra Salice ◽  
...  
Keyword(s):  
Solar Wind ◽  
Radiation Belt ◽  
Climate Models ◽  
Stratospheric Ozone ◽  
Energetic Electron ◽  
Predictor Variable ◽  
Electron Precipitation ◽  
Atmospheric Effects ◽  
Solar Wind Parameters ◽  
Earth’S Radiation Belt

<p>Energetic electron precipitation (EEP) from the plasma sheet and the radiation belts, can collide with gases in the atmosphere and deposit their energy. EEP increase the production of NOx and HOx, which will catalytically destroy stratospheric ozone, an important element of atmospheric dynamics. Therefore, measurement of latitudinal extent of the precipitation boundaries is important in quantifying atmospheric effects of Sun-Earth interaction and threats to spacecrafts and astronauts in the Earth's radiation belt.<br>This study uses measurements by MEPED detectors of six NOAA/POES and EUMETSAT/METOP satellites from 2004 to 2014 to determine the latitudinal boundaries of EEP and its variability with geomagnetic activity and solar wind drivers. Variation of the boundaries with respect to different particle energies and magnetic local time is studied. Regression analyses are applied to determine the best predictor variable based on solar wind parameters and geomagnetic indices. The result will be a key element for constructing a model of EEP variability to be applied in atmosphere climate models.</p>

scholarly journals Energetic electron precipitation during high-speed solar wind stream driven storms

2011 ◽  
Vol 116 (A5) ◽  
Author(s):  
Nigel P. Meredith ◽  
Richard B. Horne ◽  
Mai Mai Lam ◽  
Michael H. Denton ◽  
Joseph E. Borovsky ◽  
...  
Keyword(s):  
Solar Wind ◽  
High Speed ◽  
Energetic Electron ◽  
Electron Precipitation ◽  
Solar Wind Stream ◽  
Speed Solar Wind ◽  
High Speed Solar Wind

scholarly journals Energetic electron precipitation into the middle atmosphere-Constructing the loss cone fluxes from MEPED POES

2016 ◽  
Vol 121 (6) ◽  
pp. 5693-5707 ◽  
Author(s):  
H. Nesse Tyssøy ◽  
M. I. Sandanger ◽  
L.-K. G. Ødegaard ◽  
J. Stadsnes ◽  
A. Aasnes ◽  
...  
Keyword(s):  
Middle Atmosphere ◽  
Energetic Electron ◽  
Electron Precipitation ◽  
Loss Cone

scholarly journals Comparison between CNA and energetic electron precipitation: simultaneous observation by Poker Flat Imaging Riometer and NOAA satellite

2005 ◽  
Vol 23 (5) ◽  
pp. 1555-1563 ◽  
Author(s):  
Y.-M. Tanaka ◽  
M. Ishii ◽  
Y. Murayama ◽  
M. Kubota ◽  
H. Mori ◽  
...  
Keyword(s):  
Pitch Angle ◽  
Electron Flux ◽  
Energetic Electron ◽  
Energetic Particles ◽  
Electron Precipitation ◽  
Angle Distribution ◽  
Pitch Angle Distribution ◽  
Loss Cone ◽  
Isotropic Pitch ◽  
Trapped Electron

Abstract. The cosmic noise absorption (CNA) is compared with the precipitating electron flux for 19 events observed in the morning sector, using the high-resolution data obtained during the conjugate observations with the imaging riometer at Poker Flat Research Range (PFRR; 65.11° N, 147.42° W), Alaska, and the low-altitude satellite, NOAA 12. We estimate the CNA, using the precipitating electron flux measured by NOAA 12, based on a theoretical model assuming an isotropic pitch angle distribution, and quantitatively compare them with the observed CNA. Focusing on the eight events with a range of variation larger than 0.4dB, three events show high correlation between the observed and estimated CNA (correlation coefficient (r0)>0.7) and five events show low correlation (r0<0.5). The estimated CNA is often smaller than the observed CNA (72% of all data for 19 events), which appears to be the main reason for the low-correlation events. We examine the assumption of isotropic pitch angle distribution by using the trapped electron flux measured at 80° zenith angle. It is shown that the CNA estimated from the trapped electron flux, assuming an isotropic pitch angle distribution, is highly correlated with the observed CNA and is often overestimated (87% of all data). The underestimate (overestimate) of CNA derived from the precipitating (trapped) electron flux can be interpreted in terms of the anisotropic pitch angle distribution similar to the loss cone distribution. These results indicate that the CNA observed with the riometer may be quantitatively explained with a model based on energetic electron precipitation, provided that the pitch angle distribution and the loss cone angle of the electrons are taken into account. Keywords. Energetic particles, precipitating – Energetic particles, trapped – Ionosphere-magnetosphere interactions

scholarly journals The driving mechanisms of particle precipitation during the moderate geomagnetic storm of 7 January 2005

2007 ◽  
Vol 25 (9) ◽  
pp. 2053-2068 ◽  
Author(s):  
N. Longden ◽  
F. Honary ◽  
A. J. Kavanagh ◽  
J. Manninen
Keyword(s):  
Solar Wind ◽  
Geomagnetic Storm ◽  
Geomagnetic Activity ◽  
Dynamic Pressure ◽  
Energetic Electron ◽  
Recovery Phase ◽  
Global Scale ◽  
Electron Precipitation ◽  
Particle Precipitation ◽  
Substorm Activity

Abstract. The arrival of an interplanetary coronal mass ejection (ICME) triggered a sudden storm commencement (SSC) at ~09:22 UT on the 7 January 2005. The ICME followed a quiet period in the solar wind and interplanetary magnetic field (IMF). We present global scale observations of energetic electron precipitation during the moderate geomagnetic storm driven by the ICME. Energetic electron precipitation is inferred from increases in cosmic noise absorption (CNA) recorded by stations in the Global Riometer Array (GLORIA). No evidence of CNA was observed during the first four hours of passage of the ICME or following the sudden commencement (SC) of the storm. This is consistent with the findings of Osepian and Kirkwood (2004) that SCs will only trigger precipitation during periods of geomagnetic activity or when the magnetic perturbation in the magnetosphere is substantial. CNA was only observed following enhanced coupling between the IMF and the magnetosphere, resulting from southward oriented IMF. Precipitation was observed due to substorm activity, as a result of the initial injection and particles drifting from the injection region. During the recovery phase of the storm, when substorm activity diminished, precipitation due to density driven increases in the solar wind dynamic pressure (Pdyn) were identified. A number of increases in Pdyn were shown to drive sudden impulses (SIs) in the geomagnetic field. While many of these SIs appear coincident with CNA, SIs without CNA were also observed. During this period, the threshold of geomagnetic activity required for SC driven precipitation was exceeded. This implies that solar wind density driven SIs occurring during storm recovery can drive a different response in particle precipitation to typical SCs.

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