How to change or reorder grouping by 'time.season'?

[hafez-ahmad]

Hey everyone!

is there any way to change or reorder month names [
'DJF' 'JJA' 'MAM' 'SON'] during seasonal grouping? I like to change
'DJF' 'JJA' 'MAM' 'SON' combination and find out winter season Dec+Jan+Feb+Mar=winter season.

Your assistant highly appreciated.

[dcherian]

How about

import numpy as np
import xarray as xr

ds = xarray.tutorial.open_dataset("air_temperature")


months = ds.time.dt.month
seasons = xr.full_like(months, fill_value="none", dtype="U4")
seasons.name = "season"

# set values
seasons[months.isin([12, 1, 2, 3])] = "DJFM"
seasons[months.isin([4, 5])] = "AM"
seasons[months.isin([6, 7, 8])] = "JJA"
seasons[months.isin([9, 10, 11])] = "SON"

# seasonal mean, then reindex to get nicely ordered seasons
ds.groupby(seasons).mean().reindex(season=["DJFM", "AM", "JJA", "SON"])

<xarray.Dataset>
Dimensions:  (lat: 25, lon: 53, season: 4)
Coordinates:
  * season   (season) <U4 'DJFM' 'AM' 'JJA' 'SON'
  * lat      (lat) float32 75.0 72.5 70.0 67.5 65.0 ... 25.0 22.5 20.0 17.5 15.0
  * lon      (lon) float32 200.0 202.5 205.0 207.5 ... 322.5 325.0 327.5 330.0
Data variables:
    air      (season, lat, lon) float32 248.0 247.9 247.6 ... 299.4 299.4 299.5

[hafez-ahmad]

@dcherian thank you so much
it works.

can I make facet map with this ?

[dcherian]

can I make facet map with this ?

Try it out!