Description:

Reanalyses are widely used to study atmospheric processes and as observationally-based benchmarks for model validation. Meanwhile, in addition to their many independent applications, long-term observational datasets provide both essential inputs for assimilation in climate reanalyses and valuable constraints for evaluating reanalysis products. The first phase of the SPARC Reanalysis Intercomparison Project (S-RIP, https://s-rip.github.io/) coordinated a wide-ranging intercomparison to identify differences between reanalyses and their underlying causes, provide guidance on the appropriate use of reanalyses in scientific studies, and improve reanalysis products through collaborations with reanalysis centers and data users. As part of the nascent S-RIP Phase 2 (S-RIP2) activity, recently-released and forthcoming reanalyses (e.g., ERA5, JRA-3Q) will be comprehensively evaluated within the context of the previous Phase 1 assessments. Phase 2 will also have new foci including stratosphere-troposphere coupling and exchange, extreme weather events and their links to the stratosphere, evaluation of chemical reanalyses, and analyses in support of model-reanalysis intercomparison activities (e.g., CCMI-2022, CMIP7, WMO GAFIS). 

This session welcomes studies of the planning, development, evaluation, and intercomparison of meteorological and chemical reanalyses. We also solicit presentations describing advances in long-term data records formed from directly merging multiple space-borne and/or ground-based observations, using these datasets to advance our understanding of the middle atmosphere, and addressing future observational needs in support of reanalyses and climate data records. This session serves as an open invitation to the community to participate in the S-RIP2 activity.