The ROM SAF RO climate data record: validation and inter-mission consistency
Presenter:
Hans Gleisner
Danish Meteorological Institute
Danish Meteorological Institute
Talk
Numerous studies have demonstrated the accuracy of GNSS Radio Occultation (RO) data, and their usefulness as a stable climate reference. Homogeneity of the data records are obtained by reprocessing of the data using uniform processing software throughout the length of the climate record. We here present results from a validation of the ROM SAF Climate Data Record (CDR), based on a new reprocessing of Metop, CHAMP, GRACE, and COSMIC data, quantifying differences between the RO missions as well as differences of RO data relative to ERA-Interim reanalysis data. We also validate the method used to adjust the monthly mean RO climatologies for sampling errors.
A central issue for the generation of RO-based CDRs is whether data from different satellite missions can be combined to form long time series of multi-mission data. This presentation explores the consistency of gridded monthly-mean data from different RO missions during mission overlap periods. It is shown that within a core region from the upper troposphere to the middle stratosphere, roughly 8 to 30 kilometers (depending on latitude and geophysical variable), there is a high consistency amongst the RO missions, allowing for the construction of long-term stable data sets for use in climate studies and climate monitoring. At higher altitudes the RO mission consistency decreases, and below about 6 km we find biases leading to reduced RO mission consistency.
Presentation in PDF:
