Abstract
During high-speed solar wind stream (HSS) events, energetic electrons from the Earth's inner magnetosphere transfer solar wind energy to the high-latitude upper atmosphere, which may affect chemical compositions in the region. We conduct a study on the production of nitrogen oxides (NOx) in the polar middle atmosphere by energetic electron precipitation (EEP) during HSS events in the period of international polar year 2007–2008 northern winter. During this period, the geomagnetic activity was generally quiet and there were no major solar events, which indicates that the EEPs were mostly associated with HSS events. The electron flux immediately increases with the onset of HSS events and remains elevated during the passage of the events. The estimation of the directly produced NOx by EEPs was attempted by using the correlation between NOx and dynamic tracers such as CO and CH4. It was found that the direct effect of EEPs on NOx reaches down to about 55-km altitude and the amount is estimated to be about 2 ppbv. This result indicates that the variations of polar stratospheric NOx in winter are mostly associated with dynamical processes such as vertical transport and horizontal mixing. We also found that the middle atmospheric O3 depletion during HSS events seems to be related to the EEP-induced NOx at least in the uppermost stratosphere in the polar region.
| Original language | English |
|---|---|
| Pages (from-to) | 9788-9801 |
| Number of pages | 14 |
| Journal | Journal of Geophysical Research: Space Physics |
| Volume | 123 |
| Issue number | 11 |
| DOIs | |
| Publication status | Published - 2018 Nov |
Bibliographical note
Funding Information:This work was supported by the grant PE18020 from the Korea Polar Research Institute. Y.-S. Kwak was supported by the “Operation and application researches of space weather research center” project from Korea Astronomy and Space Science Institute (KASI) and by Air Force Office of Scientific Research (AFOSR)/Asian Office of Aerospace Research and Development (AOARD) grant FA2386-18-1-0107. Y.-S. Lee acknowledges support from Chungnam National University. We would like to thank the European Space Agency (ESA) for making the MIPAS level-1b data set available at http://www.imk-asf.kit.edu/english/308.php. The MLS/Aura data are provided by the NASA Goddard Earth Sciences Data and Information Service Center (GES DISC) at http://disc.sci.gsfc.nasa.gov/Aura/data-holdings/MLS. POES data are provided by NOAA National Geophysical Data Center. The solar wind data obtained by ACE is provided at OMNIWeb/CDAWeb in the National Space Science Data Center (NSSDC), the National Aeronautics and Space Administration/Goddard Space Flight Center (NASA/GSFC).
Funding Information:
This work was supported by the grant PE18020 from the Korea Polar Research Institute. Y.-S. Kwak was supported by the “Operation and application researches of space weather research center” project from Korea Astronomy and Space Science Institute (KASI) and by Air Force Office of Scientific Research (AFOSR)/Asian Office of Aerospace Research and Development (AOARD) grant FA2386-18-1-0107. Y.-S. Lee acknowledges support from Chungnam National University. We would like to thank the European Space Agency (ESA) for making the MIPAS level-1b data set available at http://www.imk-asf.kit.edu/ english/308.php. The MLS/Aura data are provided by the NASA Goddard Earth Sciences Data and Information Service Center (GES DISC) at http://disc.sci.gsfc. nasa.gov/Aura/data-holdings/MLS. POES data are provided by NOAA National Geophysical Data Center. The solar wind data obtained by ACE is provided at OMNIWeb/CDAWeb in the National Space Science Data Center (NSSDC), the National Aeronautics and Space Administration/Goddard Space Flight Center (NASA/GSFC).
Publisher Copyright:
© 2018. American Geophysical Union. All Rights Reserved.
All Science Journal Classification (ASJC) codes
- Space and Planetary Science
- Geophysics