Vertical column abundances of HCN deduced from ground-based infrared solar spectra: Long-term trend and variability |
| |
Authors: | E. Mahieu C. P. Rinsland R. Zander P. Demoulin L. Delbouille G. Roland |
| |
Affiliation: | (1) Institute of Astrophysics, University of Liège, 4000 Liège, Belgium;(2) Atmospheric Sciences Division, NASA Langley Research Center, Hampton, Virginia, USA |
| |
Abstract: | A set of high-resolution IR solar spectra recorded at the International Scientific Station of the Jungfraujoch, Switzerland, from 84/06 to 93/06, and at the National Solar Observatory McMath-Pierce solar telescope facility on Kitt Peak, Arizona, U.S.A. from 78/05 to 92/07 have been analyzed to determine the vertical column abundances of hydrogen cyanide, HCN, above the two stations. The analysis was based on least-squares curve fitting of calculated spectra to the observations encompassing the P4 and the P8 lines of HCN respectively located at 3299.5273 and 3287.2483 cm–1. The results obtained for the two stations indicate that no significant long-term trend affects either of the two databases; however, this analysis reveals variable increases during springtime of up to a factor of 2 in the HCN total column above the Jungfraujoch and even up to 3 above Kitt Peak. The calculated mean vertical column abundances, excluding the spring observations, are equal to (2.55±0.30)×1015 molec./cm2 (S.D.) and (2.75±0.30)×1015 molec./cm2 respectively above the Jungfraujoch and the Kitt Peak observatories. Based on a realistic volume mixing ratio profile, these columns translate into mean volume mixing ratios equal to 190×10–12 ppv at the respective altitudes of the stations. |
| |
Keywords: | HCN infrared solar observations |
本文献已被 SpringerLink 等数据库收录! |
|