Speaker
Description
After the Montreal protocol banned ozone depleting substances, first signs of an ozone recovery in the stratosphere were observed starting in 1997. Recent studies have reported positive trends indicating that ozone is recovering in the upper stratosphere at mid-latitudes. However, stratospheric ozone trends from various ground-based data sets still differ in magnitude.
To partly explain such differences, we investigate how trends are affected by suspicious anomalies in the data. We present trend estimates from ground-based ozone data at mid-latitudes and demonstrate how they can be improved by considering data anomalies in the trend estimation.
Ozone trend profiles are compared for ground-based instruments from the Network for the Detection of Atmospheric Composition Change (NDACC) in Central Europe. Similar analyses are planned for co-located instruments at the supersite in Lauder, New Zealand. The careful analysis of stratospheric ozone time series and their uncertainties is crucial to improve trend estimations of stratospheric ozone profiles.
