@prefix dcat: <http://www.w3.org/ns/dcat#> .
@prefix dct: <http://purl.org/dc/terms/> .
@prefix foaf: <http://xmlns.com/foaf/0.1/> .
@prefix gsp: <http://www.opengis.net/ont/geosparql#> .
@prefix locn: <http://www.w3.org/ns/locn#> .
@prefix owl: <http://www.w3.org/2002/07/owl#> .
@prefix schema: <http://schema.org/> .
@prefix vcard: <http://www.w3.org/2006/vcard/ns#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .

<https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15> a schema:DataDownload,
        schema:Dataset,
        dcat:Dataset,
        dcat:Distribution,
        foaf:Document ;
    dct:bibliographicCitation "Read the documentation, GEM terms of use and how to cite: https://data.g-e-m.dk/guides. Please get in touch with the GEM secretariat if you need help to cite correctly." ;
    dct:description "Snow depth is measured using GeoRadar along the SNZ transect running from the coastline towards the top of Aucella (ending in about 400 meters above sea level). Measurements are primarily conducted by end of winter, before snow melt is initiated. Positions are given in UTM coordinates (WGS 84, UTM Zone 27 N). Systematic measurements with GeoRadar were implemented in the GeoBasis snow monitoring in 2016. The measured two-way travel time is used to estimate the snow depth by relating this to manual measurements of the snow depth performed along the transect. From linear relationships between the manually measured depths and the travel time, an approximated velocity is found and the snow depth estimated from depth = velocity * one way travel time. For all transects the two way travel time, manual measurements, the approximated velocity and estimated snow depth is recorded alongside the coordinates and information regarding the frequency of the antenna used." ;
    dct:identifier "https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15" ;
    dct:issued "2026-05-20T13:19:10.673413"^^xsd:dateTime,
        "2026-05-20T16:14:48.172145"^^xsd:dateTime ;
    dct:modified "2026-05-20T16:14:48.164233"^^xsd:dateTime,
        "2026-05-20T16:14:48.166638"^^xsd:dateTime ;
    dct:publisher [ a foaf:Agent ;
            foaf:homepage <https://data.g-e-m.dk> ;
            foaf:name "Greenland Ecosystem Monitoring" ],
        [ a foaf:Agent ;
            foaf:homepage <https://data.g-e-m.dk> ;
            foaf:name "Greenland Ecosystem Monitoring" ] ;
    dct:spatial [ a dct:Location ;
            locn:geometry "POLYGON ((-20.5700 74.4700, -20.5700 74.4700, -20.5700 74.4700, -20.5700 74.4700))"^^gsp:wktLiteral ] ;
    dct:temporal [ a dct:PeriodOfTime ;
            dcat:endDate "2018-05-10"^^xsd:date ;
            dcat:startDate "2016-04-24"^^xsd:date ],
        [ a dct:PeriodOfTime ;
            dcat:endDate "2018-05-10"^^xsd:date ;
            dcat:startDate "2016-04-24"^^xsd:date ] ;
    dct:title "SNZ GeoRadar snow depth" ;
    schema:about [ a schema:Thing ;
            schema:name "zackenberg-research-station" ] ;
    schema:citation "Read the documentation, GEM terms of use and how to cite: https://data.g-e-m.dk/guides. Please get in touch with the GEM secretariat if you need help to cite correctly." ;
    schema:creator [ a schema:Organization ;
            schema:contactPoint [ a schema:ContactPoint ;
                    schema:contactType "customer service" ;
                    schema:name "University of Copenhagen (UCPH - Partner 3)" ;
                    schema:url "https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15" ] ;
            schema:name "University of Copenhagen (UCPH - Partner 3)" ] ;
    schema:dateModified "2026-05-20T16:14:48.164233" ;
    schema:datePublished "2020-01-01",
        "2020-01-01T00:00:00" ;
    schema:description "Snow depth is measured using GeoRadar along the SNZ transect running from the coastline towards the top of Aucella (ending in about 400 meters above sea level). Measurements are primarily conducted by end of winter, before snow melt is initiated. Positions are given in UTM coordinates (WGS 84, UTM Zone 27 N). Systematic measurements with GeoRadar were implemented in the GeoBasis snow monitoring in 2016. The measured two-way travel time is used to estimate the snow depth by relating this to manual measurements of the snow depth performed along the transect. From linear relationships between the manually measured depths and the travel time, an approximated velocity is found and the snow depth estimated from depth = velocity * one way travel time. For all transects the two way travel time, manual measurements, the approximated velocity and estimated snow depth is recorded alongside the coordinates and information regarding the frequency of the antenna used." ;
    schema:distribution <https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15> ;
    schema:identifier "https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15" ;
    schema:keywords "ARCTIC",
        "CLIMATE INDICATORS",
        "ECOSYSTEMS",
        "GEOGRAPHY",
        "GREENLAND",
        "PHYSICAL GEOGRAPHY",
        "SNOW-ICE" ;
    schema:license "https://creativecommons.org/licenses/by-sa/4.0/" ;
    schema:name "SNZ GeoRadar snow depth" ;
    schema:publisher [ a schema:Organization ;
            schema:contactPoint [ a schema:ContactPoint ;
                    schema:contactType "customer service" ;
                    schema:name "Greenland Ecosystem Monitoring" ;
                    schema:url "https://data.g-e-m.dk" ] ;
            schema:name "Greenland Ecosystem Monitoring" ] ;
    schema:spatialCoverage [ a schema:Place ;
            schema:geo [ a schema:GeoShape ;
                    schema:polygon "{\"type\": \"Polygon\", \"coordinates\": [[[-20.57, 74.47], [-20.57, 74.47], [-20.57, 74.47], [-20.57, 74.47]]]}" ] ] ;
    schema:temporalCoverage "2016-04-24/2018-05-10" ;
    schema:url "https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15" ;
    schema:variableMeasured [ a schema:PropertyValue ;
            schema:description "Manual probings along GeoRadar transect" ;
            schema:name "Manual_measurements_m" ;
            schema:propertyID <https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15#column=Manual_measurements_m> ;
            schema:unitText "M" ;
            schema:url <https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15#column=Manual_measurements_m> ],
        [ a schema:PropertyValue ;
            schema:description "Frequency of antenna used for survey" ;
            schema:name "Antenna_frequency_MHz" ;
            schema:propertyID <https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15#column=Antenna_frequency_MHz> ;
            schema:unitText "Mhz" ;
            schema:url <https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15#column=Antenna_frequency_MHz> ],
        [ a schema:PropertyValue ;
            schema:description "Estimated snow depth, based on liniar relationsships between the travel time and manual measurements" ;
            schema:name "SnowDepth_m" ;
            schema:propertyID <https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15#column=SnowDepth_m> ;
            schema:unitText "M" ;
            schema:url <https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15#column=SnowDepth_m> ],
        [ a schema:PropertyValue ;
            schema:description "Altitude above sea level, given in meters" ;
            schema:name "Elevation" ;
            schema:propertyID <https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15#column=Elevation> ;
            schema:unitText "M" ;
            schema:url <https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15#column=Elevation> ],
        [ a schema:PropertyValue ;
            schema:description "Positions are given in UTM coordinates (WGS 84, UTM Zone 27N)" ;
            schema:name "Northing" ;
            schema:propertyID <https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15#column=Northing> ;
            schema:unitText "M" ;
            schema:url <https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15#column=Northing> ],
        [ a schema:PropertyValue ;
            schema:description "The raw travel time" ;
            schema:name "TwoWayTravelTime_ns" ;
            schema:propertyID <https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15#column=TwoWayTravelTime_ns> ;
            schema:unitText "ns" ;
            schema:url <https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15#column=TwoWayTravelTime_ns> ],
        [ a schema:PropertyValue ;
            schema:name "Date" ;
            schema:propertyID <https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15#column=Date> ;
            schema:unitText "YYYY-MM-DD" ;
            schema:url <https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15#column=Date> ],
        [ a schema:PropertyValue ;
            schema:description "Positions are given in UTM coordinates (WGS 84, UTM Zone 27N)" ;
            schema:name "Easting" ;
            schema:propertyID <https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15#column=Easting> ;
            schema:unitText "M" ;
            schema:url <https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15#column=Easting> ] ;
    schema:version "1" ;
    owl:versionInfo "1" ;
    dcat:accessURL <https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15> ;
    dcat:contactPoint [ a vcard:Organization ;
            vcard:fn "[{\"author_name\": \"Greenland Ecosystem Monitoring\"}]" ] ;
    dcat:distribution <https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15> ;
    dcat:keyword "ARCTIC",
        "CLIMATE INDICATORS",
        "ECOSYSTEMS",
        "GEOGRAPHY",
        "GREENLAND",
        "PHYSICAL GEOGRAPHY",
        "SNOW-ICE" ;
    dcat:landingPage <https://data.g-e-m.dk/datasets/10.17897/NKJM-9B15> ;
    dcat:theme "zackenberg-research-station" .

