Deliverable No. 1.2 Provision of process-focused, user-relevant and Arctc linkages metrics through ESMValTool

• Main Authors: Cattiaux, Julien, Douville, Hervé, Docquier, David, Jung, Thomas, Massonnet, François, Msadek, Rym, Shaffrey, Len
• Format: Text
• Language: English
• Published: Zenodo 2018
• Subjects: Arctic; Climate change
• Online Access: https://dx.doi.org/10.5281/zenodo.3567706; https://zenodo.org/record/3567706

The APPLICATE Task 1.2.3 is dedicated to the development of diagnostics/metrics relevant to investigate climate linkages between the Arctic and the mid-latitudes. Here we report the progress made within this task and provide several lists of diagnostics/metrics that can be used by APPLICATE partners and the wider community for weather and climate model evaluation and/or climate change analyses. There are still important gaps in our knowledge regarding the linkages between Arctic changes and mid-latitude variability and changes, both in the atmosphere and in the ocean. Substantial work has been made in Task 1.2.3 to review the literature and select the most appropriate diagnostics for documenting Arctic - mid-latitude linkages. Novel diagnostics have been developed, and several others are still under development. Partners involved in this task already use these diagnostics as metrics for the evaluation of their institutional weather and climate models. The software codes used to calculate the new diagnostics/metrics are now available for APPLICATE partners and very soon available for the wider community. Key diagnostics/metrics will become available in ESMValTool v2.0. The upcoming release of CMIP6 and PAMIP multi-model data constitutes an ideal opportunity (Task 1.3) to sorely test these software codes and to implement well-tested diagnostics/metrics into ESMValTool. The ultimate objectives are (i) to document potential improvements in the representation of mid-latitude dynamics since CMIP5 (including linkages with the Arctic), (ii) to quantify CMIP6 projected changes in the atmospheric circulation, their uncertainties, and the contribution of the Arctic region, and (iii) to narrow model uncertainties in future projections by using the developed metrics as emergent constraints (Task 1.5).