The Test data is available from 10 January 2019 onwards from the MARS archive, while a test dataset is currently available for one day on the FTP server: 17 March 2019. 

MARS

If you have access to ECMWF systems you can retrieve test data from MARS archive using keywords:

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If you don't have access to ECMWF computers but would still like to access a large subset of test data you can use ECMWF WebAPI service.

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#!/usr/bin/env python
from ecmwfapi import ECMWFDataServer
server = ECMWFDataServer()

server.retrieve({
    "dataset":   "cams_esuite",
    "stream":    "oper",
    "type":      "fc",
    "date":      "2017070120190110/to/2017071020190119",
    "time":      "00",    
    "step":      "0/to/23/by/1",
    "levtype":   "sfc",
    "format":    "netcdf",
    "param" :    "aod550",         # see parameter table at http://atmosphere.copernicus.eu/ftp-access-global-data
    "grid":      "0.4/0.4",        # 0.4 x 0.4 regular lat-lon grid
    "area":      "70/-35/35/60",   # N/E/S/W area boundaries
    "target":    "/tmp/cams_test_201707.nc"
})

FTP dissemination

The test dataset is available through ECPDS FTP dissemination systems in these directories:

/DATA/CAMS_GLOBAL_TEST
/DATA/CAMS_GLOBAL_ADDITIONAL_TEST
/DATA/CAMS_EUROPE_BC_TEST

You can use your normal FTP account to access the data. The list of parameters is the same as in the current data streams.

If everything else fails ...

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