JpGU-AGU Joint Meeting 2017

Presentation information

[JJ] Oral

A (Atmospheric and Hydrospheric Sciences) » A-AS Atmospheric Sciences, Meteorology & Atmospheric Environment

[A-AS11] [JJ] Atmospheric Chemistry

Tue. May 23, 2017 3:30 PM - 5:00 PM 301B (International Conference Hall 3F)

convener:Hitoshi Irie(Center for Environmental Remote Sensing, Chiba University), Toshinobu Machida(National Institute for Environmental Studies), Hiroshi Tanimoto(National Institute for Environmental Studies), Yoko Iwamoto(Graduate School of Biosphere Science, Hiroshima University), Chairperson:Naoko Saitoh(Center for Environmental Remote Sensing)

4:30 PM - 4:45 PM

[AAS11-11] Temporal evolution of minor species observed with ground-based FTIR at Syowa Station, Antarctica in 2007, 2011, and 2016

*Hideaki Nakajima1, Isao Murata2, Yoshihiro Nagahama1, Masanori Takeda2, Yoshihiro Tomikawa3, Hideharu Akiyoshi1 (1.National Institute for Environmental Studies, 2.Tohoku University, 3.National Institute of Polar Research)

Keywords:FTIR, Syowa Station, Cly, ozone, ozone hole

Vertical profiles of O3, HNO3, HCl, and ClONO2 were retrieved from solar spectra taken with a ground-based Fourier-Transform infrared spectrometer (FTIR) installed at Syowa Station, Antarctica (69.0S, 39.6E) from March to December, 2007, September to November, 2011, and October to December, 2016. We analyzed temporal variation of these species combined with ClO data taken by Aura/MLS, and ClONO2 data taken by Envisat/MIPAS satellite sensors at 18 and 22 km over Syowa Station. In early July, polar stratospheric clouds (PSCs) started to be formed over Syowa Station. With the return of sunlight at Syowa Station in early July, ClONO2 and HCl showed depleted values while ClO showed enhanced values. At all three altitudes (18 and 22 km), when ClO concentrations started to decline in early September, HCl started to increase rapidly, while the increase in ClONO2 was gradual. The Cly partitioning between HCl, ClONO2, and ClO showed difference at different altitudes. At the altitudes of 18 km, where ozone was almost depleted, ClO and HNO3 amounts are low, so conversion to HCl was favored rather than ClONO2. Whereas, at 22 km, sufficient ozone still remained, at an amount that ClONO2 formation from ClO and NOy species continued to occur at this altitude. This is the first in the world to observe O3 destruction and recovery process of reservoir chlorine (HCl and ClONO2) after disappearance of PSCs using ground-based FTIR in the Antarctic.