1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
|
#!/usr/bin/env python3
import requests
import datetime
import pytz
import requests
import os
from multiprocessing import cpu_count
from multiprocessing.pool import ThreadPool
import subprocess
import misc
BASE='https://opendata.dwd.de/weather/nwp'
def get_current_run():
# we allow up to 3h of slack for DWD to upload the latest run
tz = pytz.timezone('UTC')
now = datetime.datetime.now(datetime.timezone.utc)
corrected = now - datetime.timedelta(hours=3)
run = int(corrected.hour / 6) * 6
return (f'{run:02d}', corrected.strftime('%Y%m%d'))
def download_url(args):
url, dest = args
r = requests.get(url)
try:
with open(dest, 'wb') as f:
f.write(r.content)
print(f'Downloaded {dest}')
except Exception as e:
print(f'Failed to download {dest}:\n', e)
def unpack_bz2(dest):
res = subprocess.run(['bzip2', '-df', dest])
if res.returncode != 0:
print(f'There was an error unpacking {dest}:', res.stderr)
def download_dwd_gribs(config, date, run, target):
model = config['model']
model_long = config['model_long']
misc.create_output_dir(config['output'])
to_download = []
for step in config['steps']:
step_str = f'{step:03d}'
for parameter in config['pressure_level_parameters']:
parameter2 = parameter.upper() if config['parameter_caps_in_filename'] else parameter
for level in config['pressure_levels']:
filename = f'{model_long}_regular-lat-lon_pressure-level_{date}{run}_{step_str}_{level}_{parameter2}.grib2.bz2'
URL = f'{BASE}/{model}/grib/{run}/{parameter}/{filename}'
to_download.append((URL, os.path.join(config['output'], filename)))
for parameter in config['single_level_parameters']:
parameter2 = parameter.upper() if config['parameter_caps_in_filename'] else parameter
filename = f'{model_long}_regular-lat-lon_single-level_{date}{run}_{step_str}_{parameter2}.grib2.bz2'
URL = f'{BASE}/{model}/grib/{run}/{parameter}/{filename}'
to_download.append((URL, os.path.join(config['output'], filename)))
for _ in ThreadPool(cpu_count()).imap_unordered(download_url, to_download):
pass
print('Done Downloading. Uncompressing...')
for _ in ThreadPool(cpu_count()).imap_unordered(unpack_bz2, [dest for _, dest in to_download]):
pass
downloaded_gribs = [dest.removesuffix('.bz2') for _, dest in to_download]
res = subprocess.run(['grib_copy'] + downloaded_gribs + [target])
if res.returncode != 0:
print('grib_copy failed with: ', res.stderr)
res = subprocess.run(['rm', '-f'] + downloaded_gribs)
if res.returncode != 0:
print('rm failed with: ', res.stderr)
def load_data(config):
run, date = get_current_run()
target = os.path.join(config['output'], f'combined_{date}_{run}.grib2')
if not os.path.exists(target):
download_dwd_gribs(config, date, run, target)
config = {
'output':'dwd_icon-eu',
'model':'icon-eu',
'model_long':'icon-eu_europe',
'parameter_caps_in_filename':True,
'pressure_level_parameters': [
't',
'relhum',
'u',
'v',
'fi',
'clc'
],
'single_level_parameters': [
'pmsl',
't_2m',
'relhum_2m'
],
'pressure_levels':[ 1000, 950, 925, 900, 875, 850, 825, 800, 775, 700, 600, 500, 400, 300, 250, 200, 150, 100 ],
'steps':[0, 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, 42, 45, 48]
}
if __name__ == '__main__':
load_data(config)
|