Improving trajectory calculations by FLEXPART 10.4+ using single-image super-resolution

Autor(en)
Rüdiger Brecht, Lucie Bakels, Alex Bihlo, Andreas Stohl
Abstrakt

Lagrangian trajectory or particle dispersion models as well as semi-Lagrangian advection schemes require meteorological data such as wind, temperature and geopotential at the exact spatiotemporal locations of the particles that move independently from a regular grid. Traditionally, these high-resolution data have been obtained by interpolating the meteorological parameters from the gridded data of a meteorological model or reanalysis, e.g., using linear interpolation in space and time. However, interpolation is a large source of error for these models. Reducing them requires meteorological input fields with high space and time resolution, which may not always be available and can cause severe data storage and transfer problems. Here, we interpret this problem as a single-image super-resolution task. That is, we interpret meteorological fields available at their native resolution as low-resolution images and train deep neural networks to upscale them to a higher resolution, thereby providing more accurate data for Lagrangian models. We train various versions of the state-of-The-Art enhanced deep residual networks for super-resolution (EDSR) on low-resolution ERA5 reanalysis data with the goal to upscale these data to an arbitrary spatial resolution. We show that the resulting upscaled wind fields have root-mean-squared errors half the size of the winds obtained with linear spatial interpolation at acceptable computational inference costs. In a test setup using the Lagrangian particle dispersion model FLEXPART and reduced-resolution wind fields, we find that absolute horizontal transport deviations of calculated trajectories from "true"trajectories calculated with un-degraded 0.5g×g0.5g winds are reduced by at least 49.5g% (21.8g%) after 48gh relative to trajectories using linear interpolation of the wind data when training on 2gto 1g(4g to 2g) resolution data.

Organisation(en)
Institut für Meteorologie und Geophysik
Externe Organisation(en)
Universität Hamburg, Memorial University of Newfoundland
Journal
Geoscientific Model Development
Band
16
Seiten
2181-2192
Anzahl der Seiten
12
ISSN
1991-959X
DOI
https://doi.org/10.5194/gmd-16-2181-2023
Publikationsdatum
04-2023
Peer-reviewed
Ja
ÖFOS 2012
105206 Meteorologie
ASJC Scopus Sachgebiete
Allgemeine Erdkunde und Planetologie, Modelling and Simulation
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/83103c60-a7a6-47f4-aeb8-20eeef799ff7