Formulating requests

To be able to make a request, you need to decide on a few main points:

• Which variables do you want?
  • And in which dataset are these variables located? (E.g. ERA5-Land).
• For which years do you want the variable?
• Do you want to the data globally, or specify a bounding box (using --area).
• (For pressure level data:) on which levels do you want the data.

Note

All available arguments are listed in the CLI Reference

Example request

A typical request in era5cli can look like the following:

era5cli hourly \
    --land \
    --variables 2m_temperature 2m_dewpoint_temperature \
    --startyear 2000 \
    --endyear 2020 \
    --splitmonths True \
    --area 53.6 3.3 50.7 7.5

This request asks for hourly data of the ERA5-Land dataset, more specifically the 2m_temperature and 2m_dewpoint_temperature variables.

Additionally, data from the year 2000 up to (and including) 2020 is requested, with the final files being split up by months. Lastly, an area is extracted from the dataset (in this case only the Netherlands).

Using the info command

To be able to formulate a request, you can make use of the --help and info arguments in era5cli.

The info argument takes a name, out of the ones shown below. For example,

era5cli info levels

will list all available pressure levels.

info argument	shows:
levels	available pressure levels
2Dvars	available single level / 2D variables
3Dvars	available pressure level / 3D variables
land	available variables in ERA5-land

Tip

You can enter a variable name (such as total_precipitation) to show if the variable is available, and in which list.

For example:

era5cli info total_precipitation

returns:

total_precipitation is in the list(s): 2Dvars, land

You can view the available variable names in the CLI Reference