NOAA@NSIDC would like to alert users of an upcoming update to the Sea Ice Index FTP directory structure and file names. The current FTP directory (ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/) contains monthly data and images directly under the top-level directory with one subdirectory for each month. The monthly subdirectories house both northern and southern hemisphere data files and images within them (Figure 1). Beginning 18 January 2017, all Sea Ice Index data will be organized by hemisphere at the top level, then parsed by temporal resolution, daily or monthly, and organized further by file type: tabulated data, browse images, or Shapefiles (Figure 2). In addition, the product is being versioned up to version 2.1, so all file names will have v2.1 in the file name instead of v2 only. If you have any scripts that access Sea Ice Index data, you will need to update them with the new file names and new FTP directory tree being introduced on 18 January 2017 to continue accessing the Sea Ice Index product. The following major changes should be noted:
All monthly images are moving and the trend images have a new file name. For example, the current image file path: ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/Apr/N_201504_extn_v2.png will be moved to: ~/G02135/north/monthly/images/04_Apr/N_201504_extn_v2.1.png and the current trend image file path: ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/Apr/N_04_trnd_v2.png will be moved and renamed to: ~/G02135/north/monthly/images/04_Apr/N_04_trend_v2.1.png
The monthly data files are moving and the format will change from a space delimited .txt file to a comma separated .csv file. For example, the current data file path: ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/Apr/N_04_area_v2.txt will be moved and renamed to: ~/G02135/north/monthly/data/N_04_extent_v2.1.csv
The near-real-time and final daily data will be within a single file but the directory structure will remain the same. For example, the data files currently at: ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/north/daily /data/NH_seaice_extent_nrt_v2.csv and ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/north/daily /data/NH_seaice_extent_final_v2.csv will be combined to form: ~/G02135/north/daily/data/N_seaice_extent_v2.1.csv
Daily climatology data files are also being renamed. For example, the current data file path: ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/north /daily/data/NH_seaice_extent_climatology_1981-2010_v2.csv will be renamed to: ~/G02135/north/daily/data/N_seaice_extent_climatology_1981-2010_v2.1.csv
Monthly shapefiles are moving. For example, the current shapefile path: ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/shapefiles /Apr/shp_extent/extent_N_201504_polygon_v2.zip will be moved to: ~/G02135/norht/monthly/shapefiles/shp_extent/04_Apr/ extent_N_201504_polygon_v2.1.zip and the current shapefile path: ftp://sidads.colorado.edu/DATASETS/NOAA/G02135 /shapefiles/Apr/shp_median/median_N_04_1981_2010_polyline_v2.zip will be moved to: ~/G02135/norht/monthly/shapefiles /shp_median/ median_N_04_1981_2010_polyline_v2.1.zip
