Transport versus energetic particle precipitation: Northern polar stratospheric NO<SUB>x</SUB> and ozone in January-March 2012

DOI: 
10.1002/2015JD024217
Publication date: 
01/05/2016
Main author: 
Päivärinta, S. -M.
IAA authors: 
Funke, B.;Gardini, A.
Authors: 
Päivärinta, S. -M.;Verronen, P. T.;Funke, B.;Gardini, A.;Seppälä, A.;Andersson, M. E.
Journal: 
Journal of Geophysical Research (Atmospheres)
Refereed: 
Yes
Publication type: 
Article
Volume: 
121
Pages: 
6085-6100
Abstract: 
In early 2012, a strong sudden stratospheric warming (SSW) took place, accompanied by several medium-scale solar proton events (SPEs). Here we use a chemistry transport model (CTM) in order to assess the relative contributions of (1) intensified downward transport of odd nitrogen (NO<SUB>x</SUB>) and (2) in situ production of NO<SUB>x</SUB> by protons, on stratospheric NO<SUB>x</SUB> and ozone during January-March 2012. The CTM is constrained by an upper boundary condition for reactive nitrogen (NO<SUB>y</SUB>) species, based on satellite observations from Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on board Envisat, and includes a new parameterization of the SPE-caused effects on NO<SUB>y</SUB> and odd hydrogen (HO<SUB>x</SUB>) species. We found that the amount of NO<SUB>x</SUB> increases due to both transport and in situ production effects, the intensified descent of NO<SUB>x</SUB> dominating the middle and upper stratospheric impact. The model results indicate NO<SUB>x</SUB> enhancements of 120-3300% (5-48 ppbv) between 38 and 50 km, caused by the transport of mesosphere/lower thermosphere NO<SUB>x</SUB> down to the stratosphere following the SSW. The SPEs increase NO<SUB>x</SUB> by up to 820-1200% (14-21 ppbv) at 33 to 50 km. The effect on the stratospheric ozone is larger following the downward transport of NO<SUB>x</SUB> than during and after the SPEs. The model predicts ozone losses of up to 17% and 9% at around 40 km due to transport and SPE effects, respectively.
Database: 
ADS
SCOPUS
WOK
URL: 
https://ui.adsabs.harvard.edu/#abs/2016JGRD..121.6085P/abstract
ADS Bibcode: 
2016JGRD..121.6085P
Keywords: 
middle atmosphere dynamics;energetic particle precipitation;solar proton event;sudden stratospheric warming;odd nitrogen;ozone