3-30-2019

The 2017 monthly fields were created using the following commands:
* combined 5dy fields into a single file
cdo copy ../soda3.3.2_5dy_ice_reg_2017_*  soda3.3.2_5dy_ice_reg_2017.nc
* compute monthly average and center date on the 15th
cdo setday,15 -monmean soda3.3.2_5dy_ice_reg_2017.nc  soda3.3.2_mn_ice_reg_2017.nc