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The influence of large solar proton events on the atmosphere
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Jackman, Charles H. |
| Copyright Year | 2012 |
| Description | Solar proton events (SPEs) can cause changes in constituents in the Earth s polar middle atmosphere. A number of large SPEs have occurred over the past 50 years and tend to happen most frequently near solar maximum. The highly energetic protons cause ionizations, excitations, dissociations, and dissociative ionizations of the background constituents. Complicated ion chemistry leads to HOx (H, OH, HO2) production and dissociation of N2 leads to NOy (N, NO, NO2, NO3, N2O5, HNO3, HO2NO2, ClONO2, BrONO2) production. Both the HOx and NOy increases can result in changes to ozone in the stratosphere and mesosphere. The HOx increases lead to short-lived (~days) ozone decreases in the mesosphere and upper stratosphere. The NOy increases lead to long-lived (~several months) stratospheric ozone changes because of the long lifetime of NOy constituents in this region. UARS HALogen Occultation Experiment (HALOE) instrument observations showed SPE-caused polar stratospheric NOx (NO+NO2) increases over 10 ppbv in September 2000 due to the very large SPE of July 2000, which are reasonably well simulated with the Whole Atmosphere Community Climate Model (WACCM). WACCM-computed SPE-caused polar stratospheric ozone decreases >10% continued for up to 5 months past the largest events in the past 50 years, however, SPE-caused total ozone changes were not found to be statistically significant. Small polar middle atmospheric temperature changes of <4 K have also been predicted to occur as a result of the larger SPEs. The polar atmospheric effects of large SPEs during solar cycle 23 and 24 will be emphasized in this presentation. |
| File Size | 37626 |
| Page Count | 2 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20120014296 |
| Archival Resource Key | ark:/13960/t4dn94k8q |
| Language | English |
| Publisher Date | 2012-09-18 |
| Access Restriction | Open |
| Subject Keyword | Meteorology And Climatology Halogen Occultation Experiment Gas Dissociation Atmospheric Effects Middle Atmosphere Hydrogen Compounds Solar Activity Effects Nitrogen Oxides Ozone Climate Models Solar Protons Solar Cycles Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
