Fix issue with recipe ref fire dependency (#4420)

Author: jlenh

environment.yml

@@ -10,7 +10,6 @@ channels:
 
 dependencies:
   - aiohttp
-  - arviz
   - cartopy
   - cdo >=2.3.0
   - cdsapi

environment_osx.yml

@@ -10,7 +10,6 @@ channels:
 
 dependencies:
   - aiohttp
-  - arviz
   - cartopy
   - cdo >=2.3.0
   - cdsapi

esmvaltool/diag_scripts/fire/diagnostic_run_confire.py

@@ -22,7 +22,6 @@
 from pathlib import Path
 from typing import TYPE_CHECKING
 
-import arviz as az
 import cartopy.crs as ccrs
 import cf_units
 import iris
@@ -32,6 +31,7 @@
 import matplotlib.pyplot as plt
 import numpy as np
 import pandas as pd
+import xarray as xr
 from matplotlib.colors import ListedColormap
 
 from esmvaltool.diag_scripts.shared import ProvenanceLogger
@@ -357,11 +357,11 @@ def _select_post_param_name(name: str) -> np.array:
         return np.reshape(out, new_shape)
 
     try:
-        trace = az.from_netcdf(trace, engine="netcdf4")
+        trace = xr.open_datatree(trace, engine="netcdf4")
     except (ValueError, OSError) as expt:
         logger.debug("_select_post_param error %s", expt)
-    params = trace.to_dict()["posterior"]
-    params_names = params.keys()
+    params = trace["posterior"]
+    params_names = list(trace["posterior"].data_vars)
     params = [_select_post_param_name(var) for var in params_names]
     return params, list(params_names)
 

pyproject.toml

@@ -31,7 +31,6 @@ dynamic = [
 ]
 dependencies = [
     "aiohttp",
-    "arviz",
     "cartopy",
     "cdo",
     "cdsapi",