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Inventory_2015 - README
Inventory of cryospheric landforms of the arid diagonal of South America
(high Central Andes, Atacama Region, northern Chile)
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1. OVERVIEW
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Inventory_2015 is a GIS-ready (ESRI shapefile) version of the regional inventory
of glaciers and periglacial (ice-rich permafrost) landforms of the Atacama arid
diagonal, originally published as:

  Garcia, A., Ulloa, C., Amigo, G., Milana, J. P. & Medina, C. (2017).
  An inventory of cryospheric landforms in the arid diagonal of South America
  (high Central Andes, Atacama region, Chile).
  Quaternary International, 438, 4-19.
  https://doi.org/10.1016/j.quaint.2017.04.033

This shapefile is distributed as supporting data for:

  Ulloa, C., Garcia, A. & Beniest, A.
  "Introducing a new normalized cryospheric index (NCI) to categorize
   sub-watersheds on arid environments."
  Manuscript egusphere-2025-1198 (EGUsphere / Copernicus).
  [Insert final journal reference and article DOI here upon publication]

It is the source inventory from which the cryospheric landform polygons (and
their coordinates) used in the NCI study were taken.

Scope: this file contains the COMPLETE inventory (all mapped watersheds), not a
Copiapo-only subset. It holds 6137 landform polygons across five watersheds
(field COD_CUENC). The Copiapo watershed corresponds to COD_CUENC = 034 and
contains 1862 landforms, matching the figure reported in the NCI article. See
Section 5 for the watershed codes and how to filter the Copiapo subset.

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2. SPATIAL REFERENCE AND FORMAT
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  Format .................. ESRI Shapefile (polygon)
  Geometry ................ Polygon (5871) and MultiPolygon (266); 6137 total
  Coordinate ref. system .. UTM Zone 19S, WGS84 (EPSG:32719); units: metres
  Extent (UTM 19S, metres):
     Easting  .............. 356193 to 572954
     Northing .............. 6709753 to 7202683
  Extent (WGS84, degrees):
     Longitude ............. -70.480 to -68.265
     Latitude .............. -29.739 to -25.292

Note: the attribute table also stores per-feature geographic (COORD_X/COORD_Y)
and projected (COORDUTM_X/COORDUTM_Y) coordinates of each landform.

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3. LANDFORM CLASSES (field CLASE)
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The class label is stored in Spanish in the field CLASE. English equivalents and
counts (whole inventory):

  CLASE (Spanish)          English                      Count   Sum area (km2)
  ---------------------------------------------------------------------------
  Glaciar descubierto      Debris-free glacier            357        50.77
  Glaciar cubierto         Debris-covered glacier          51         6.41
  Glaciar de roca          Rock glacier                   469        43.87
  Ladera de criofluxion    Gelifluction slope / talus    3132      1515.20
  Protalus lobe            Protalus lobe                  2128        76.95
  ---------------------------------------------------------------------------
  Total                                                  6137      1693.20

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4. ATTRIBUTE FIELDS (data dictionary)
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  Field         Description                                            Unit
  CLASE         Landform class (see Section 3; Spanish label)          text
  AREA          Polygon area                                           km2
  HECTAREAS     Polygon area (= AREA x 100)                            hectares
  PERIMETRO     Polygon perimeter                                      km
  COORD_X       Longitude of the landform (representative point)       deg (WGS84)
  COORDUTM_X    Easting of the landform (representative point)         m (UTM 19S)
  COORD_Y       Latitude of the landform (representative point)        deg (WGS84)
  COORDUTM_Y    Northing of the landform (representative point)        m (UTM 19S)
  ALT_MAX       Maximum elevation                                      m a.s.l.
  ALT_MIN       Minimum elevation                                      m a.s.l.
  ALT_MEAN      Mean elevation                                         m a.s.l.
  ORIEN_MEAN    Mean surface orientation / aspect                      deg (0-360)
  PEN_MEAN      Mean surface slope                                     deg
  COD_CUENC     Watershed code (Chilean DGA/BNA coding)                text
  COD_SUBC      Sub-catchment code                                     text
  COD_SSUBC     Sub-sub-catchment code                                 text
  PFI_MEAN      Mean permafrost-favourability index (0 = unfavourable, 0-1
                1 = favourable) -- please confirm definition/source
  RAD_MEAN      Mean incoming solar radiation over the landform        (source units)
                -- please confirm units against the source study
  Q_BASE        Estimated base-flow / water contribution indicator     (source units)
                -- please confirm definition/units
  OBS           Free-text observation/note (populated for 1 feature:   text
                "requiere rev, Landslide")
  Area_cuenc    Area of the (sub-)catchment containing the landform    km2
  Area_1        GIS-recomputed polygon area (alternative to AREA)      km2

Fields flagged with "please confirm" (PFI_MEAN, RAD_MEAN, Q_BASE, Area_cuenc,
Area_1) are derived/auxiliary attributes; their exact definitions and units
should be verified against the original processing before reuse.

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5. WATERSHED CODES (field COD_CUENC)
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  COD_CUENC   Landforms   Notes
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  034            1862      Copiapo River watershed (study area of the NCI article)
  030            2325      neighbouring Atacama watershed (DGA/BNA coding)
  038            1909      neighbouring Atacama watershed (DGA/BNA coding)
  031              29      neighbouring Atacama watershed (DGA/BNA coding)
  032               7      neighbouring Atacama watershed (DGA/BNA coding)
  (blank)           5      incomplete records (see Section 6)

Codes follow the Chilean DGA/BNA (Direccion General de Aguas / Banco Nacional de
Aguas) hydrological coding. COD_SUBC and COD_SSUBC give the finer sub-catchment
and sub-sub-catchment subdivisions.

To extract the Copiapo subset (the 1862 landforms used in the NCI study), filter
by COD_CUENC = '034' (e.g. in QGIS/ArcGIS: "COD_CUENC" = '034', or with GeoPandas:
gdf[gdf['COD_CUENC'] == '034']). The Copiapo subset breaks down as: 62 debris-free
glaciers, 16 debris-covered glaciers, 173 rock glaciers, 848 gelifluction taluses
and 763 protalus lobes.

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6. DATA-QUALITY NOTES
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- 5 features have empty watershed codes and zero coordinates/elevations; these are
  incomplete records and should be reviewed or removed before analysis.
- A small number of features (15) have PERIMETRO values above 50 km, which are
  unusually large for individual landforms and may be geometry/topology artifacts
  in complex multipart polygons; inspect before using PERIMETRO for those.
- Coordinate fields (COORD_X/COORD_Y, COORDUTM_X/COORDUTM_Y) and elevation fields
  hold 0 for the 5 incomplete records above; treat 0 as "no data" for these.

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7. FILE COMPONENTS
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The shapefile is made of the following sidecar files, which must be kept together:

  Inventory_2015.shp .... geometry
  Inventory_2015.shx .... geometry index
  Inventory_2015.dbf .... attribute table
  Inventory_2015.prj .... coordinate reference system (UTM 19S / WGS84)
  Inventory_2015.cpg .... attribute-table character encoding
  Inventory_2015.sbn / .sbx .. attribute/spatial index (optional; ESRI)

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8. CITATION
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Please cite the original inventory publication:

  Garcia, A., Ulloa, C., Amigo, G., Milana, J. P. & Medina, C. (2017).
  An inventory of cryospheric landforms in the arid diagonal of South America
  (high Central Andes, Atacama region, Chile). Quaternary International, 438,
  4-19. https://doi.org/10.1016/j.quaint.2017.04.033

And, if using this deposited version, the dataset and the NCI article:

  Ulloa, C., Garcia, A. & Beniest, A. (2026). Inventory of cryospheric landforms
  of the Atacama arid diagonal (GIS version) [Data set]. Zenodo.

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9. LICENSE
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Creative Commons Attribution 4.0 International (CC BY 4.0).
https://creativecommons.org/licenses/by/4.0/

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10. CONTACT
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Corresponding author (Invetory article): Ayón García - ayon.garcia@uda.cl
University of Atacama, Geology Department, Avenida Copayapu #485, Copiapo, Chile.

Corresponding author (NCI article): Christopher Ulloa - christopher.ulloa@uda.cl
University of Atacama, Geology Department, Avenida Copayapu #485, Copiapo, Chile.

Dataset file: Inventory_2015 (shapefile)
README last updated: 2026-07-27
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