CMIP6 image

Global Mean Surface Temperature


Overview

This notebook uses similar techniques to the ECS notebook. Please refer to that notebook for details.

Prerequisites

Concepts

Importance

Notes

Understanding of NetCDF

Helpful

Familiarity with metadata structure

Seaborn

Helpful

  • Time to learn: 10 minutes


Imports

from matplotlib import pyplot as plt
import xarray as xr
import numpy as np
import dask
from dask.diagnostics import progress
from tqdm.autonotebook import tqdm
import intake
import fsspec
import seaborn as sns

%matplotlib inline
/tmp/ipykernel_1487/1335193511.py:6: TqdmExperimentalWarning: Using `tqdm.autonotebook.tqdm` in notebook mode. Use `tqdm.tqdm` instead to force console mode (e.g. in jupyter console)
  from tqdm.autonotebook import tqdm
col = intake.open_esm_datastore("https://storage.googleapis.com/cmip6/pangeo-cmip6.json")
col
/srv/conda/envs/notebook/lib/python3.10/site-packages/intake_esm/cat.py:283: FutureWarning: DataFrame.applymap has been deprecated. Use DataFrame.map instead.
  .applymap(type)
/srv/conda/envs/notebook/lib/python3.10/site-packages/intake_esm/cat.py:283: FutureWarning: DataFrame.applymap has been deprecated. Use DataFrame.map instead.
  .applymap(type)
/srv/conda/envs/notebook/lib/python3.10/site-packages/intake_esm/cat.py:283: FutureWarning: DataFrame.applymap has been deprecated. Use DataFrame.map instead.
  .applymap(type)
/srv/conda/envs/notebook/lib/python3.10/site-packages/intake_esm/cat.py:283: FutureWarning: DataFrame.applymap has been deprecated. Use DataFrame.map instead.
  .applymap(type)
/srv/conda/envs/notebook/lib/python3.10/site-packages/intake_esm/cat.py:283: FutureWarning: DataFrame.applymap has been deprecated. Use DataFrame.map instead.
  .applymap(type)
/srv/conda/envs/notebook/lib/python3.10/site-packages/intake_esm/cat.py:283: FutureWarning: DataFrame.applymap has been deprecated. Use DataFrame.map instead.
  .applymap(type)
/srv/conda/envs/notebook/lib/python3.10/site-packages/intake_esm/cat.py:283: FutureWarning: DataFrame.applymap has been deprecated. Use DataFrame.map instead.
  .applymap(type)
/srv/conda/envs/notebook/lib/python3.10/site-packages/intake_esm/cat.py:283: FutureWarning: DataFrame.applymap has been deprecated. Use DataFrame.map instead.
  .applymap(type)
/srv/conda/envs/notebook/lib/python3.10/site-packages/intake_esm/cat.py:283: FutureWarning: DataFrame.applymap has been deprecated. Use DataFrame.map instead.
  .applymap(type)
/srv/conda/envs/notebook/lib/python3.10/site-packages/intake_esm/cat.py:283: FutureWarning: DataFrame.applymap has been deprecated. Use DataFrame.map instead.
  .applymap(type)
/srv/conda/envs/notebook/lib/python3.10/site-packages/intake_esm/cat.py:283: FutureWarning: DataFrame.applymap has been deprecated. Use DataFrame.map instead.
  .applymap(type)
/srv/conda/envs/notebook/lib/python3.10/site-packages/intake_esm/cat.py:283: FutureWarning: DataFrame.applymap has been deprecated. Use DataFrame.map instead.
  .applymap(type)

pangeo-cmip6 catalog with 7674 dataset(s) from 514818 asset(s):

unique
activity_id 18
institution_id 36
source_id 88
experiment_id 170
member_id 657
table_id 37
variable_id 700
grid_label 10
zstore 514818
dcpp_init_year 60
version 736
derived_variable_id 0
[eid for eid in col.df['experiment_id'].unique() if 'ssp' in eid]
['ssp585',
 'ssp245',
 'ssp370SST-lowCH4',
 'ssp370-lowNTCF',
 'ssp370SST-lowNTCF',
 'ssp370SST-ssp126Lu',
 'ssp370SST',
 'ssp370pdSST',
 'ssp119',
 'ssp370',
 'esm-ssp585-ssp126Lu',
 'ssp126-ssp370Lu',
 'ssp370-ssp126Lu',
 'ssp126',
 'esm-ssp585',
 'ssp245-GHG',
 'ssp245-nat',
 'ssp460',
 'ssp434',
 'ssp534-over',
 'ssp245-stratO3',
 'ssp245-aer',
 'ssp245-cov-modgreen',
 'ssp245-cov-fossil',
 'ssp245-cov-strgreen',
 'ssp245-covid',
 'ssp585-bgc']

There is currently a significant amount of data for these runs:

expts = ['historical', 'ssp245', 'ssp585']

query = dict(
    experiment_id=expts,
    table_id='Amon',
    variable_id=['tas'],
    member_id = 'r1i1p1f1',
)

col_subset = col.search(require_all_on=["source_id"], **query)
col_subset.df.groupby("source_id")[
    ["experiment_id", "variable_id", "table_id"]
].nunique()
/srv/conda/envs/notebook/lib/python3.10/site-packages/intake_esm/cat.py:283: FutureWarning: DataFrame.applymap has been deprecated. Use DataFrame.map instead.
  .applymap(type)
/srv/conda/envs/notebook/lib/python3.10/site-packages/intake_esm/cat.py:283: FutureWarning: DataFrame.applymap has been deprecated. Use DataFrame.map instead.
  .applymap(type)
/srv/conda/envs/notebook/lib/python3.10/site-packages/intake_esm/cat.py:283: FutureWarning: DataFrame.applymap has been deprecated. Use DataFrame.map instead.
  .applymap(type)
experiment_id variable_id table_id
source_id
ACCESS-CM2 3 1 1
AWI-CM-1-1-MR 3 1 1
BCC-CSM2-MR 3 1 1
CAMS-CSM1-0 3 1 1
CAS-ESM2-0 3 1 1
CESM2-WACCM 3 1 1
CIESM 3 1 1
CMCC-CM2-SR5 3 1 1
CMCC-ESM2 3 1 1
CanESM5 3 1 1
E3SM-1-1 3 1 1
EC-Earth3 3 1 1
EC-Earth3-CC 3 1 1
EC-Earth3-Veg 3 1 1
EC-Earth3-Veg-LR 3 1 1
FGOALS-f3-L 3 1 1
FGOALS-g3 3 1 1
FIO-ESM-2-0 3 1 1
GFDL-CM4 3 1 1
GFDL-ESM4 3 1 1
IITM-ESM 3 1 1
INM-CM4-8 3 1 1
INM-CM5-0 3 1 1
IPSL-CM6A-LR 3 1 1
KACE-1-0-G 3 1 1
KIOST-ESM 3 1 1
MIROC6 3 1 1
MPI-ESM1-2-HR 3 1 1
MPI-ESM1-2-LR 3 1 1
MRI-ESM2-0 3 1 1
NESM3 3 1 1
NorESM2-LM 3 1 1
NorESM2-MM 3 1 1
TaiESM1 3 1 1
def drop_all_bounds(ds):
    drop_vars = [vname for vname in ds.coords
                 if (('_bounds') in vname ) or ('_bnds') in vname]
    return ds.drop(drop_vars)

def open_dset(df):
    assert len(df) == 1
    ds = xr.open_zarr(fsspec.get_mapper(df.zstore.values[0]), consolidated=True)
    return drop_all_bounds(ds)

def open_delayed(df):
    return dask.delayed(open_dset)(df)

from collections import defaultdict
dsets = defaultdict(dict)

for group, df in col_subset.df.groupby(by=['source_id', 'experiment_id']):
    dsets[group[0]][group[1]] = open_delayed(df)
dsets_ = dask.compute(dict(dsets))[0]
/srv/conda/envs/notebook/lib/python3.10/site-packages/xarray/coding/times.py:832: SerializationWarning: Unable to decode time axis into full numpy.datetime64 objects, continuing using cftime.datetime objects instead, reason: dates out of range
  dtype = _decode_cf_datetime_dtype(data, units, calendar, self.use_cftime)
/srv/conda/envs/notebook/lib/python3.10/site-packages/xarray/coding/times.py:832: SerializationWarning: Unable to decode time axis into full numpy.datetime64 objects, continuing using cftime.datetime objects instead, reason: dates out of range
  dtype = _decode_cf_datetime_dtype(data, units, calendar, self.use_cftime)
/srv/conda/envs/notebook/lib/python3.10/site-packages/xarray/core/indexing.py:560: SerializationWarning: Unable to decode time axis into full numpy.datetime64 objects, continuing using cftime.datetime objects instead, reason: dates out of range
  array = array.get_duck_array()

Calculate global means:

def get_lat_name(ds):
    for lat_name in ['lat', 'latitude']:
        if lat_name in ds.coords:
            return lat_name
    raise RuntimeError("Couldn't find a latitude coordinate")

def global_mean(ds):
    lat = ds[get_lat_name(ds)]
    weight = np.cos(np.deg2rad(lat))
    weight /= weight.mean()
    other_dims = set(ds.dims) - {'time'}
    return (ds * weight).mean(other_dims)
expt_da = xr.DataArray(expts, dims='experiment_id', name='experiment_id',
                       coords={'experiment_id': expts})

dsets_aligned = {}

for k, v in tqdm(dsets_.items()):
    expt_dsets = v.values()
    if any([d is None for d in expt_dsets]):
        print(f"Missing experiment for {k}")
        continue

    for ds in expt_dsets:
        ds.coords['year'] = ds.time.dt.year

    # workaround for
    # https://github.com/pydata/xarray/issues/2237#issuecomment-620961663
    dsets_ann_mean = [v[expt].pipe(global_mean)
                             .swap_dims({'time': 'year'})
                             .drop('time')
                             .coarsen(year=12).mean()
                      for expt in expts]

    # align everything with the 4xCO2 experiment
    dsets_aligned[k] = xr.concat(dsets_ann_mean, join='outer',
                                 dim=expt_da)
dsets_aligned_ = dask.compute(dsets_aligned)[0]
source_ids = list(dsets_aligned_.keys())
source_da = xr.DataArray(source_ids, dims='source_id', name='source_id',
                         coords={'source_id': source_ids})

big_ds = xr.concat([ds.reset_coords(drop=True)
                    for ds in dsets_aligned_.values()],
                    dim=source_da)

big_ds
<xarray.Dataset>
Dimensions:        (year: 451, experiment_id: 3, source_id: 34)
Coordinates:
  * year           (year) float64 1.85e+03 1.851e+03 ... 2.299e+03 2.3e+03
  * experiment_id  (experiment_id) <U10 'historical' 'ssp245' 'ssp585'
  * source_id      (source_id) <U16 'ACCESS-CM2' 'AWI-CM-1-1-MR' ... 'TaiESM1'
Data variables:
    tas            (source_id, experiment_id, year) float64 287.0 287.0 ... nan
df_all = big_ds.sel(year=slice(1900, 2100)).to_dataframe().reset_index()
df_all.head()
year experiment_id source_id tas
0 1900.0 historical ACCESS-CM2 287.019917
1 1900.0 historical AWI-CM-1-1-MR 286.958154
2 1900.0 historical BCC-CSM2-MR 287.996260
3 1900.0 historical CAMS-CSM1-0 287.084974
4 1900.0 historical CAS-ESM2-0 287.263682
sns.relplot(data=df_all,
            x="year", y="tas", hue='experiment_id',
            kind="line", ci="sd", aspect=2);
/srv/conda/envs/notebook/lib/python3.10/site-packages/seaborn/axisgrid.py:854: FutureWarning: 

The `ci` parameter is deprecated. Use `errorbar='sd'` for the same effect.

  func(*plot_args, **plot_kwargs)
../../_images/a44b9396df9b5f62bf48b66c1619e8dc0badb779cf2093f525344d61882832fd.png

Summary

In this notebook, we accessed data for historical, SSP245, and SSP585 runs from a collection of CMIP6 models and plotted the multimodel-mean global average surface air temperature for each run.

What’s next?

We will use CMIP6 data to analyze precipitation intensity under a warming climate.

Resources and references