Representation of small-scale processes of importance for polar regions in numerical weather prediction models

• Main Author: Svensson, G.
• Format: Conference Object
• Language: English
• Published: 2023
• Subjects: Arctic; Arctic Ocean; Sea ice
• Online Access: https://gfzpublic.gfz-potsdam.de/pubman/item/item_5021041

Representation of small-scale processes in the Polar regions are known to deteriorate the quality of weather forecasts and generate biases in climate simulations. The focus of the YOPP process task team has been to understand the cause of these biases for processes that are more prevailing in these regions, such as turbulence in stably stratified boundary layers, mixed-phase clouds and fluxes important for the exchange between the atmosphere and the underlying snow and/or sea ice. Findings from the YOPPsiteMIP project, that is based on land stations around the Arctic ocean and a suite of forecast models will be presented. The representation of the transformation of a warm and moist airmass in the ECMWF IFS forecasts and ERA5 on its way northward during the YOPP-MOSAiC targeted observational period (TOP) will be discussed. How these biases can be understood through experiments with a coupled atmosphere ocean single column model, the AOSCM, will also be presented. If time allows, planned community activities with the aim to further advance the understanding of process representation will be described.