Author: Moritz Shore (moritz.shore@nibio.no)
Date: March, 2026
ERA5 Meteorological data for SWAT+
To apply ERA5 data to a SWAT+ setup, you need to first independently
download said data from open-meteo.com. Please note, there is
a limit on downloads for the free tier, which is why (for now) it is not
directly implemented in miljotools. When downloading the data for use in
this package, please follow the following template EXACTLY, only
changing the grid cells (list format), start and end date, and perhaps
the variables (UNTESTED – make sure to adjust the
open_meteo_variables parameter). Any deviations will
probably cause errors. If you would like to make the function more
robust for your use case, feel free to submit a pull request!
Here is the template URL:
https://open-meteo.com/en/docs/historical-weather-api?timezone=Europe%2FBerlin&models=era5&hourly=&daily=temperature_2m_max,temperature_2m_min,precipitation_sum,shortwave_radiation_sum,wind_speed_10m_mean,relative_humidity_2m_mean&wind_speed_unit=ms&bounding_box=59.522321,10.82686,59.865845,11.111253&start_date=2013-01-01&end_date=2022-12-31&location_mode=csv_coordinates&cell_selection=nearest&csv_coordinates=59.75,+10.75%0A59.75,11.00%0A59.50,10.75%0A59.50,11.00%0A#hourly_weather_variablesOnce you have downloaded your data, You can use the following function to apply ERA5 meteorological data to a SWAT+ setup:
require(miljotools)
era5_swatplus(open_meteo_path = "path/to/file.csv",
extract_path = "path/to/directory",
swat_setup = "path/to/directory")Please read up on the optional parameters on the help page! This function uses SWATprepR to apply the meteo data.