endataset SCAR Antarctic Digital Database ../Miscellaneous/SimpleBasemap/ADD_DerivedLowresBasemap.shp SCAR Antarctic Digital Database (ADD) Version 7.0. Downloaded 2016-2017 from: http://www.add.scar.org/ Quantarctica project team compiled ADD low resolution data. Please refer to ADD datasets for metadata. Coastline polygons north of 60°S taken from 1:10000000 datasets available on Natural Earth (http://www.naturalearthdata.com/) version 3.0.0.