High quality stratospheric radio occultation climate data

For around twenty years, satellite-based radio occultation (RO) technology has provided high-quality atmospheric data in the upper troposphere and lower stratosphere (5 km to 35 km altitude). These are used for meteorological applications such as weather forecasting, for climate monitoring and climate research, and also for space weather research. The first goal of this project is to increase the data quality of RO data in the middle and upper stratosphere (35 km to 50 km altitude). This implements an important recommendation of the International Radio Occultation Working Group, which is an RO expert group. Two easy-to-use methods developed in an earlier project will be used for the entire range of RO data since 2001. These new techniques can greatly reduce the measurement noise and effectively correct the residual influences of the Earth`s ionosphere. This improves the data quality across the entire stratosphere and thus enables more precise global climate monitoring, which in turn contributes to a better understanding of our climate system. After a thorough analysis, the complete available multi-satellite RO time series since 2001 will be processed. Based on this processed high-quality climate data, the second goal is to derive stratospheric winds and to analyse their circulation patterns over the tropics and subtropics. The advantages of the RO data used here are their high vertical resolution and long-term consistency over the entire time period. To ensure a high quality of climate monitoring, the wind fields are carefully compared with long-term weather analysis data fields, so-called reanalysis data, and these data are also used to extend them backwards to 1980. This finally makes it possible to investigate dynamic changes in height of the wind fields and changes in their circulation patterns under the influence of anthropogenic climate change of the last four decades with a reliability that was previously not possible. This exciting analysis is carried out with a focus on the changes in the tropics and subtropics, which are particularly important in the climate system. This allows us to expect new insights into the interplay between global warming and changes in circulation.