TUNER

The project 'Towards Unified Error Reporting' (TUNER) aims at providing consistent and inter-comparable error estimates for atmospheric temperature and composition measurements from space. Along with this, a consistent and inter-comparable characterization of spatial resolution and content of a priori information of the remotely sensed data shall be provided. This is important, because quantitative work with remotely sensed data -- data assimilation, data merging, time series analysis, testing of hypotheses etc. -- depend largely on the adequate characterization of the data. Currently, multiple retrieval methods are used by the different instrument groups, and along with this various approaches to error estimation are applied. Resulting errors are not always inter-comparable. Some kinds of uncertainties are sometimes not reported at all. The different altitude resolutions and the different content of prior information in the data products is a particular problem. The project 'Towards Unified Error Reporting (TUNER)' shall identify data characterization methods currently in use, investigate completeness and inter-comparability of available error estimates, develop a recommendation how unified data characterization shall be performed and how data uncertainties shall be reported, provide unified error estimates for some selected data products, and instruct data users how to best utilize these.