Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 5.668 IF 5.668
  • IF 5-year value: 6.201 IF 5-year
  • CiteScore value: 6.13 CiteScore
  • SNIP value: 1.633 SNIP 1.633
  • IPP value: 5.91 IPP 5.91
  • SJR value: 2.938 SJR 2.938
  • Scimago H <br class='hide-on-tablet hide-on-mobile'>index value: 174 Scimago H
    index 174
  • h5-index value: 87 h5-index 87
Discussion papers
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.

Submitted as: research article 12 Jun 2019

Submitted as: research article | 12 Jun 2019

Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Atmospheric Chemistry and Physics (ACP).

Chlorine partitioning near the polar vortex boundary observed with ground-based FTIR and satellites at Syowa Station, Antarctica in 2007 and 2011

Hideaki Nakajima1,2, Isao Murata2, Yoshihiro Nagahama1, Hideharu Akiyoshi1, Kosuke Saeki2,a, Takeshi Kinase3, Masanori Takeda2, Yoshihiro Tomikawa4,5, and Nicholas B. Jones6 Hideaki Nakajima et al.
  • 1National Institute for Environmental Studies, Tsukuba, Ibaraki, 305-8506, Japan
  • 2Graduate School of Environmental Studies, Tohoku University, Sendai, Miyagi, 980-8572, Japan
  • 3Meteorological Research Institute, Tsukuba, Ibaraki, 305-0052, Japan
  • 4National Institute of Polar Research, Tachikawa, Tokyo, 190-8518, Japan
  • 5The Graduate University for Advanced Studies, Tachikawa, Tokyo, 190-8518, Japan
  • 6University of Wollongong, Wollongong, New South Wales, 2522, Australia
  • anow at: Weathernews Inc., Chiba, 261-0023, Japan

Abstract. We retrieved lower stratospheric vertical profiles of O3, HNO3, and HCl from solar spectra taken with a ground-based Fourier-Transform infrared spectrometer (FTIR) installed at Syowa Station, Antarctica (69.0° S, 39.6° E) from March to December 2007 and September to November 2011. This was the first continuous measurements of chlorine species throughout the ozone hole period from the ground in Antarctica. We analyzed temporal variation of these species combined with ClO, HCl, and HNO3 data taken with the Aura/MLS (Microwave Limb Sounder) satellite sensor, and ClONO2 data taken with the Envisat/MIPAS (The Michelson Interferometer for Passive Atmospheric Sounding) satellite sensor at 18 and 22 km over Syowa Station. HCl and ClONO2 decrease occurred at both 18 and 22 km, and soon ClONO2 was almost depleted in early winter. When the sun returned to Antarctica in spring, enhancement of ClO and gradual O3 destruction were observed. During the ClO enhanced period, negative correlation between ClO and ClONO2 was observed in the time-series of the data at Syowa Station. This negative correlation was associated with the distance between Syowa Station and the inner edge of the polar vortex. We used MIROC3.2 Chemistry-Climate Model (CCM) results to see the comprehensive behavior of chlorine and related species inside the polar vortex and the edge region in more detail. From CCM model results, rapid conversion of chlorine reservoir species (HCl and ClONO2) into Cl2, gradual conversion of Cl2 into Cl2O2, increase of ClO when sunlight became available, and conversion of ClO into HCl, was successfully reproduced. HCl decrease in the winter polar vortex core continued to occur due to the transport of ClONO2 from the subpolar region to higher latitudes, providing a flux of ClONO2 from more sunlit latitudes into the polar vortex. Temporal variation of chlorine species over Syowa Station was affected by both heterogeneous chemistry related to Polar Stratospheric Cloud (PSC) occurrence deep inside the polar vortex, and transport of an NOx-rich airmass from lower latitudinal polar vortex boundary region which can produce additional ClONO2 by reaction of ClO with NO2. The deactivation pathways from active chlorine into reservoir species (HCl and/or ClONO2) were found to be highly dependent on the availability of ambient O3. At an altitude where most ozone was depleted in Antarctica (18 km), most ClO was converted to HCl. However, at an altitude where there were some O3 available (22 km), additional increase of ClONO2 from initial value can occur, similar to the case in the Arctic.

Hideaki Nakajima et al.
Interactive discussion
Status: final response (author comments only)
Status: final response (author comments only)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Login for Authors/Co-Editors] [Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement
Hideaki Nakajima et al.
Hideaki Nakajima et al.
Total article views: 322 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
257 63 2 322 3 5
  • HTML: 257
  • PDF: 63
  • XML: 2
  • Total: 322
  • BibTeX: 3
  • EndNote: 5
Views and downloads (calculated since 12 Jun 2019)
Cumulative views and downloads (calculated since 12 Jun 2019)
Viewed (geographical distribution)  
Total article views: 280 (including HTML, PDF, and XML) Thereof 278 with geography defined and 2 with unknown origin.
Country # Views %
  • 1
No saved metrics found.
No discussed metrics found.
Latest update: 14 Oct 2019
Publications Copernicus
Short summary
This paper presents temporal evolution of stratospheric chlorine and minor species related to Antarctic ozone depletion, based on FTIR measurements at Syowa Station, and satellite measurements by MLS and MIPAS in 2007 and 2011. After chlorine reservoir species were processed on PSCs and active ClO was formed, different chlorine deactivation pathways into reservoir species were identified, depending on the relative location of Syowa Station to polar vortex boundary.
This paper presents temporal evolution of stratospheric chlorine and minor species related to...