Simulation of Atmospheric Nitrous Oxide Profiles Retrieval from AIRS Observations

Nitrous Oxide is a very important greenhouse gases and ozone-depleting substances. Due to the limited observations, there are still many uncertainties to quantitatively describe the role of nitrous oxide played in both cases. We can retrieve the methane and carbon dioxide gas using thermal infrared satellite data AIRS, but it is rarely for the nitrous oxide retrieval. Therefore, this paper retrieves nitrous oxide profiles from the AIRS data with an Optimal Estimate Method for the first time in China. The issue of the a priori and channels election is discussed. Comparison of the retrieved AIRS profiles with HIPPO profiles show the retrieved profiles are in good agreement with the smoothed HIPPO profiles, and a notable improvement in this algorithm than the eigen vector regression algorithm. For pressures between 300 and 900 hPa, we got the most accurate profiles and the relative error is only 0.1%, which is consistent with the jacobian peaks of the selected channels.