Details:

Journal Title:
Journal of Geophysical Research: Space Physics
Personal Author:
Lin, Cissi Y. ; Deng, Yue ; Knipp, Delores J. ; Kilcommons, Liam M. ; Fang, Xiaohua
Lin, Cissi Y. ; Deng, Yue ; Knipp, Delores J. ; Kilcommons, Liam M. ; Fang, Xiaohua Less -
NOAA Program & Office:
CIRES (Cooperative Institute for Research in Environmental Sciences)
Description:
Satellite measurements have revealed significant enhancement of 5.3‐μm nitric oxide (NO)

emission during shock‐led interplanetary coronal mass ejections. Great discrepancies in modeled neutral

density occur during these events and may be attributed to the abnormally high NO cooling. Meanwhile, the

relative significance of protons, soft electrons, and keV‐electrons to NO emission is yet to be well determined.

The goal of this study is to identify the contribution of electron and proton precipitations to the

thermospheric NO cooling by using the Defense Meteorological Satellite Program (DMSP) data. The

observed energetic electrons and protons (0.1–30.2 keV) during 36 shock‐led interplanetary coronal mass

ejection events in 2002–2010 are binned into geomagnetic grids to provide statistical distributions of the

particle precipitation for polar regions. The distributions are incorporated into the Global

Ionosphere‐Thermosphere Model. The results show that electrons play a dominant role to NO cooling, but

protons are also important and contribute to up to a quarter of NO cooling by electrons and ions combined.

NO cooling enhancement during the events is proportional to the level of energy flux and is dominated

by the electrons in the energy band of 1.4–3.1 keV. Both total electron content (TEC) and NO cooling

enhance at the source regions, but they have different lifetime and correlation with the particle

precipitations. Generally, NO cooling and TEC enhancements have a positive correlation with the

precipitating energy. Cross correlation shows that particle precipitations have more instantaneous impact on

TEC while it takes longer for the atmosphere to heat up for cooling to proceed.


Keywords:
[+]
Coronal Mass Ejections Electrons Measurement
Source:
Journal of Geophysical Research: Space Physics, 124, 8125- 8137
DOI:
https://doi.org/10.1029/2019JA027089
Document Type:
Journal Article
Rights Information:
Other
Compliance:
Submitted
Main Document Checksum:
[+]
urn:sha256:6c6c61827e55114b268723f0be108caed8649a853a16870e3926d91caa2fcae2
Download URL:
https://repository.library.noaa.gov/view/noaa/25067/noaa_25067_DS1.pdf
File Type:

Supporting Files

• No Additional Files

More +