Shapefiles of volcanoes and nearby glaciers in South America used to demonstrate the link between glacier equilibrium line altitude (ELA) and volcano thermal anomaly.

This dataset comprises four distinct shapefiles, which were used to demonstrate how glacier ELA is affected by volcanic thermal conditions, in the Andes, South America. With the exception of ''139_Remapped_Glaciers.shp'', the shapefiles are obtained from existing, open access data from the Randolph Glacier Inventory (RGI 6.0) and the Global Volcanism Program 2013, but with the addition of information, in the shapefile''s attribute table, relevant to the study of the interaction between glaciers and volcanoes, as obtained via the GIS analysis of these datasets.

The ''600_RGI_Glaciers.shp'' shapefile comprises 600 (land-terminating, no debris-covered, > 0.1 km2) glacier polygons, which are located within 15 km from a Holocene (erupted in the past 10,000 years) volcano in South America. Crucially, the equilibrium line altitude (i.e., the elevation on the glacier where the surface mass balance, measured over 1 yr, is zero) and distance to the nearest volcano for each glacier is reported in the attribute table.

The ''37_GVP_Volacanoes.shp'' shapefile contains points for 37 South America Holocene volcanoes which have glaciers both within 1 km (volcanic-glaciers), and between 1 and 15 km (proximal glaciers). For each volcano, the difference in ELA between volcanic (<1km from volcano) and proximal (1-15 km) glaciers is reported in the attribute table, along with mean temperature and precipitation.

The ''139_Remapped_Glaciers.shp'' shapefile provides detailed and updated (relative to RGI) mapping of glaciers (as polygons) that are located within 15 km from 13 South America Holocene volcanoes for which thermal anomaly is known. The ELA of these glaciers is calculated and reported in the attribute table.

The ''13_AVTOD_Volacanoes.shp'' shapefile comprises the points for 13 Holocene volcanoes that have glaciers both within 1 km (volcanic-glaciers), and between 1 and 15 km (proximal glaciers) from their centre, as well as recorded thermal anomaly. The glacier ELA and volcano thermal data provided in the attribute table allows us to establish the quantitative relationship between volcanoes and glaciers.

A detailed description of the study based on this dataset is provided in Howcutt et al. (2023).

This project and data were supported by the NERC Global Partnerships Seedcorn fund (NE/W003724/1).

Alternate title: Polar Data Centre (PDC) record GB/NERC/BAS/PDC/01772

Date (Publication): 2023-09-01

Citation identifier: http://www.antarctica.ac.uk/dms/metadata.php?id= / GB/NERC/BAS/PDC/01772

Point of contact

Organisation name	Individual name	Electronic mail address	Role
British Antarctic Survey		pdc@bas.ac.uk	Custodian
NERC EDS UK Polar Data Centre	Howcutt, S.	pdc@bas.ac.uk	Originator

Maintenance and update frequency: Unknown

Keywords

NDGO0001

NERC OAI Harvesting

NERC_DDC

GCMD Parameter Valids

EARTH SCIENCE > Cryosphere > Glaciers/Ice Sheets > Glaciers
EARTH SCIENCE > Solid Earth > Volcanoes

BAS Free-text keywords

Andes
ELA
GPV
RGI
glacier
glacio-volcanism
ice-clad volcano
volcano

Use limitation: This data is covered by a UK Open Government Licence ( http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/)

Access constraints: Other restrictions

Other constraints: This data is covered by a UK Open Government Licence ( http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/)

Language: English

Topic category

Geoscientific information
Imagery base maps earth cover
Location

Begin date: 2000-01-01

End date: 2020-12-31

Reference system identifier: OGP / urn:ogc:def:crs:EPSG::4326

Distribution format

Distributor contact

Organisation name	Individual name	Electronic mail address	Role
Polar Data Centre - British Antarctic Survey		pdc@bas.ac.uk	Distributor

OnLine resource

Protocol	Linkage	Name
http	https://ramadda.data.bas.ac.uk/repository/entry/show?entryid=aa34005e-42ac-4204-8cb0-98c15d63761e	GET DATA

Hierarchy level: Dataset

Domain consistency

Measure identification: INSPIRE / Conformity_001

Conformance result

Title: INSPIRE Data Specification on unknown theme Guidelines

Date

Explanation: See the referenced specification

Pass: No

Statement: * 37_GVP_Volacanoes.shp and 13_AVTOD_Volacanoes.shp

It is recognised that magma vent and tectonic structures could be complex for specific volcanoes (e.g., Nevado del Huila in Colombia) and hence GVP points can underestimate the extent and exact location of volcanic activity (thus, glacio-volcanic interactions). However, a volcano by volcano (field based) analysis of the magmatic geometry and geothermal heat flux each volcano was not feasible.

* 600_RGI_Glaciers.shp and 139_Remapped_Glaciers.shp

RGI/GLIMS have acknowledged that an ~5% gross geometry error was observed for the Southern Andes (region 17) for RGI 6.0 glacier outlines due to the inclusion of seasonal glacier-peripheral snow and transient ice, which was misclassified as glacial ice. Our exclusion of glaciers smaller than 0.1 km2 will have removed the likelihood of including at least some erroneously mapped snow patches and seasonal ice cover. While checking and potentially re-mapping all 74 volcanic- and 526 proximal glaciers would have been unfeasible within the scope of this particular study, we attempted to correct such factors for 13 volcanoes with a record of measured thermal anomalies (analysis central to this research), for which all glaciers outlines were re-mapped by applying a semi-automated mapping process. Using this technique, we could efficiently extract glacier polygons before carrying out manual adjustments to improve alignment with the glacier margins observed on short-wave false colour composite imagery.