This site provides information and access to a commonly-formatted Earth system data record (ESDR) for stratospheric composition, of high relevance to the issue of ozone decline and recovery. High-quality long-term ozone and related trace gas data records are needed to (a) evaluate and understand composition changes in the atmosphere and (b) constrain model representations of atmospheric dynamics and photochemistry.
The datasets are drawn from zonal mean satellite-derived global stratospheric composition measurements from 1979 onward, as well as from GMAO MERRA (meteorological analyses) for temperature. The satellite-based abundance measurements come from high quality data from past missions (e.g., SAGE, HALOE data) as well as ongoing missions (ACE-FTS and Aura MLS). The planned data records are provided as time series zonal average profiles (versus pressure) as a function of latitude, for temperature and the following species: hydrogen chloride (HCl), ozone (O3), water vapor (H2O), chlorine monoxide (ClO), nitric acid (HNO3), methane (CH4), hydrogen fluoride (HF), nitrous oxide (N2O), nitrogen dioxide (NO2), and nitrogen oxide (NO). Additional "derived" data records, obtained via a constrained photochemical model, are planned for active chlorine (ClOx) and odd nitrogen (NOx). Data records are zonal means on a common grid, with time resolution of 1 month (and 1 day when possible, i.e. for MLS data).
The establishment of such commonly-formatted data records involves careful screening and production of "source" datasets (zonal means), the evaluation of offsets (biases) between various datasets, and assessments of spatial and temporal consistency. We provide public access to both the source data records and merged data records (if a merged product is produced) in yearly netCDF files, along with a ("README") user's guide and documentation of methodology and sample results.