Concept
We have compiled all the available observations of HCl and ClONO2 made by the Upper Atmosphere Research Satellite (UARS), ATMOS, CRISTA, ACE and Aura in equivalent PV latitude - potential temperature coordinates from the launch of UARS in September 1991 until the present. The instruments from the different platforms are inter compared in a new way. We use a single scatter diagram to simultaneously inter-compare all contemporaneous observations made by any pair of instruments at any time or place. This scatter diagram gives a good measure of any inter-instrument bias. We then use the observations made by ACE to learn the HCl/Cly ratio as a function of ozone, water, methane, and HCl. The neural network which has learned the HCl/Cly ratio can then be combined with any observations of HCl to reconstruct the Cly distribution. New in this study is the use of a neural network to perform this reconstruction and our focus on using the observed HCl distribution to reconstruct the Cly distribution in the lower stratosphere, where the Cly abundance is central to ozone depletion and recovery.
For more information you can take a look at our paper and its supplement.
Cly Data
- Cly data inferred from MLS Aura HCl and a neural network estimated HCl/Cly ratio trained by ACE data (gzipped tar file).
- Cly data inferred from UARS HALOE HCl and a neural network estimated HCl/Cly ratio trained by ACE data (gzipped tar file).
- Cly data inferred from UARS HALOE HCl adjusted to agree with MLS Aura HCl and a neural network estimated HCl/Cly ratio trained by ACE data (gzipped tar file).