Academic Journal
Cosmic Noise Absorption During Solar Proton Events in WACCM‐D and Riometer Observations
| Title: | Cosmic Noise Absorption During Solar Proton Events in WACCM‐D and Riometer Observations |
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| Authors: | Niilo Kalakoski, Antti Kero, Noora Partamies, Pekka T. Verronen, Erkka Heino |
| Source: | Journal of Geophysical Research: Space Physics. 124:1361-1376 |
| Publication Status: | Preprint |
| Publisher Information: | American Geophysical Union (AGU), 2019. |
| Publication Year: | 2019 |
| Subject Terms: | middle atmosphere, FOS: Physical sciences, energetic particle precipitation, WACCM, 01 natural sciences, 7. Clean energy, Space Physics (physics.space-ph), VDP::Mathematics and natural science: 400::Physics: 430::Astrophysics, astronomy: 438, VDP::Matematikk og Naturvitenskap: 400::Fysikk: 430::Astrofysikk, astronomi: 438, Physics - Space Physics, 13. Climate action, 0103 physical sciences, cosmic noise absorption, solar proton event, 0105 earth and related environmental sciences |
| Description: | Solar proton events (SPEs) cause large‐scale ionization in the middle atmosphere leading to ozone loss and changes in the energy budget of the middle atmosphere. The accurate implementation of SPEs and other particle ionization sources in climate models is necessary to understand the role of energetic particle precipitation in climate variability. We use riometer observations from 16 riometer stations and the Whole Atmosphere Community Climate Model with added D region ion chemistry (WACCM‐D) to study the spatial and temporal extent of cosmic noise absorption (CNA) during 62 SPEs from 2000 to 2005. We also present a correction method for the nonlinear response of observed CNA during intense absorption events. We find that WACCM‐D can reproduce the observed CNA well with some need for future improvement and testing of the used energetic particle precipitation forcing. The average absolute difference between the model and the observations is found to be less than 0.5 dB poleward of about 66° geomagnetic latitude, and increasing with decreasing latitude to about 1 dB equatorward of about 66° geomagnetic latitude. The differences are largest during twilight conditions where the modeled changes in CNA are more abrupt compared to observations. An overestimation of about 1° to 3° geomagnetic latitude in the extent of the CNA is observed due to the fixed proton cutoff latitude in the model. An unexplained underestimation of CNA by the model during sunlit conditions is observed at stations within the polar cap during 18 of the studied events. |
| Document Type: | Article Other literature type |
| File Description: | application/pdf |
| Language: | English |
| ISSN: | 2169-9402 2169-9380 |
| DOI: | 10.1029/2018ja026192 |
| DOI: | 10.48550/arxiv.1901.06884 |
| Access URL: | https://munin.uit.no/bitstream/10037/16928/3/article.pdf http://arxiv.org/abs/1901.06884 https://arxiv.org/abs/1901.06884 https://arxiv.org/pdf/1901.06884.pdf http://jultika.oulu.fi/files/nbnfi-fe201903219531.pdf https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2018JA026192 https://ui.adsabs.harvard.edu/abs/2019JGRA..124.1361H/abstract https://munin.uit.no/handle/10037/16928 https://munin.uit.no/bitstream/10037/16928/3/article.pdf https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2018JA026192 https://hdl.handle.net/10037/16928 http://urn.fi/urn:nbn:fi-fe201903219531 |
| Rights: | Wiley Online Library User Agreement arXiv Non-Exclusive Distribution |
| Accession Number: | edsair.doi.dedup.....fcfe28e43e65ee4f73fa8f796b28b84c |
| Database: | OpenAIRE |
| ISSN: | 21699402 21699380 |
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| DOI: | 10.1029/2018ja026192 |