Runoff remapping for ocean model forcing

• Main Author: Martin, Torge
• Format: Text
• Language: English
• Published: GEOMAR Helmholtz Centre for Ocean Research Kiel 2021
• Subjects: Greenland
• Online Access: https://oceanrep.geomar.de/id/eprint/53895/; https://oceanrep.geomar.de/id/eprint/53895/1/runoff_remapping-master.zip; https://git.geomar.de/open-source/runoff_remapping; https://doi.org/10.3289/SW_2_2021

A Pyhton-based toolbox to remap daily runoff fields of the JRA55-do reanalysis (Tsujino et al., 2018, https://doi.org/10.1016/j.ocemod.2018.07.002) onto any ocean model grid. Runoff from the original global JRA grid is collected and redistributed to a given model coastline. A particular feature is the optional treatment of river mouths: runoff from grid nodes, which is of exceptionally large magnitude after the basic remapping, can be radially spread to ocean nodes farther offshore. The scripts were tested successfully for NEMO ocean model configurations of various resolution (global grids ORCA025 and ORC05 as well as regional nests VIKING10, ORION10, VIKING20X and INALT20X) at GEOMAR, Kiel (see Biastoch et al., 2021, https://doi.org/10.5194/os-2021-37 for an application). General instructions are provided for how to process the original JRA runoff files and also for the optional river mouth treatment. The technique is illustrated by examples of the fragmented coast of Greenland and the Amazon river mouth. While the code is versatile, examples are given for an application with the NEMO ocean model.