Empirical correction of thermal responses in the Solar Occultation for Ice Experiment nitric oxide measurements and initial data validation results

David Gómez-Ramírez; John W C McNabb; James M Russell 3rd; Mark E Hervig; Lance E Deaver; Greg Paxton; Peter F Bernath

doi:10.1364/AO.52.002950

Empirical correction of thermal responses in the Solar Occultation for Ice Experiment nitric oxide measurements and initial data validation results

Appl Opt. 2013 May 1;52(13):2950-9. doi: 10.1364/AO.52.002950.

Authors

David Gómez-Ramírez¹, John W C McNabb, James M Russell 3rd, Mark E Hervig, Lance E Deaver, Greg Paxton, Peter F Bernath

Affiliation

¹ Department of Atmospheric and Planetary Sciences, Hampton University, 23 Tyler Street, Hampton, Virginia 23668, USA. gomezd@vt.edu

PMID: 23669760
DOI: 10.1364/AO.52.002950

Abstract

The Solar Occultation for Ice Experiment (SOFIE) makes broadband transmission measurements centered at 5.32 μm to determine the concentration profile of nitric oxide (NO). These measurements show a signal oscillation due to detector temperature variations that severely limit the accuracy of NO retrievals if corrections are not applied. An empirical correction was developed to remove this instrumental error. This paper describes the correction, its impact on the retrieval, and presents a comparison from 87 to 105 km versus coincident atmospheric chemistry experiment-Fourier transform spectrometer (ACE-FTS) measurements. The southern hemisphere (SH) shows excellent agreement between the datasets, with statistically insignificant differences. The northern hemisphere (NH) SOFIE measurements exhibit a low bias of -18.5% compared to ACE-FTS. NH measurements (sunrise observations) are still under study, and only SH NO data (sunset observations) are currently publicly available as of SOFIE data version 1.2.