This script fetchMERRA.py retrieve from MERRA-2 server --parameter [mass-mixing-ratio,pwv, aod] at --site [Hawaii, ctio] for --date [2005-1-6, a list] and write it in --dir
fetchMERRA.py --site hawaii --parameter mmr --dir /Volumes/backup/data/merra_2/hawaii/3D_gas/ --date 2005-1-6
