YorkSpace has migrated to a new version of its software. Access our Help Resources to learn how to use the refreshed site. Contact diginit@yorku.ca if you have any questions about the migration.
 

Improving Ozone Measurements from Ground and Space-Based Instruments

Loading...
Thumbnail Image

Date

2018-05-28

Authors

Najafabadi, Omid Moeini

Journal Title

Journal ISSN

Volume Title

Publisher

Abstract

Three topics that are outstanding issues in ozone research were discussed in this study. First, physical models of two primary standard instruments for total ozone measurements (the Dobson and Brewer ozone spectrophotometers) were developed to help better understand the effect of stray light on ozone measurements. The models showed that the error caused by stray light for a typical single Brewer at large ozone slant paths can be up to 5%, and up to 25% for a typical Dobson instrument. For the first time, new ozone absorption coefficients were calculated for the Brewer and Dobson instruments taking into account the effect of stray light. MAESTRO is a moderate-resolution spectrometer onboard SCISAT satellite since 2003. The O2 absorption bands are used by the MAESTRO retrieval to retrieve pressure and temperature profiles. In this study the MAESTRO p-T retrieval software was updated using the improved O2 spectroscopic parameters from HITRAN (high-resolution transmission molecular absorption database) 2012 database. The MAESTRO preliminary p-T retrievals were reprocessed using the updated software and compared with the ACE-FTS (Atmospheric Chemistry Experiment Fourier Transform Spectrometer) profiles and the processed results with HITRAN 2004. The analyses showed promising improvements to the p-T profiles below 50 km from the use of HITRAN 2012 parameters. New p-T profiles are capable to be used for the MAESTRO tangent height determination which makes the MAESTRO products independent from ACE-FTS pointing information and also leads to an improvement of the retrievals of other atmospheric constituents from the MAESTRO instrument. Finally, a unique objective method (The Differential Back Trajectory (DBT) method) was developed using the data collected at a network of ozonesonde sites to evaluate the contribution of fire ozone to the tropospheric ozone budget. Fire ozone accounted over 18 sites, located across Canada and the U.S, using the DBT method and more than 1000 ozonesonde profiles collected during summer time of 2006, 2008, 2010 and 2011. The analysis showed that ozone amounts at sites nearer to the large fires were less influenced by the fires.

Description

Keywords

Citation