Classification framework and semantic labeling for Big Earth Data

Figures & data

Figure 1. Flowchart providing an overview of the research on data resource classification and the multidimensional label management system.

Table 1. Classification system for Big Earth Data disciplines.

Primary Category Name	Secondary Category Name
Atmosphere	Temperature, Altitude, Precipitation, Humidity/Dryness, Evaporation, Sunshine, Atmospheric pressure, Wind, Radiation, Visibility, Cloud, Atmospheric electricity, Atmospheric water vapor, Atmospheric trace gases, Greenhouse gases, Aerosol, Reactive gases, Atmospheric radioactive substance, Atmospheric ozone, Dry and wet deposition, Atmospheric quality, Meteorological disaster, Satellite weather, Radar weather, Others
Terrestrial surface	Land use/Land cover, Topography, Geomorphology, Soil, Desert, Wetland, Forest, Grassland, Farmland, Vegetation, Land surface parameter, Earth surface processes, Drainage basin and river system, Hydrology, Surface water, Groundwater, Water environment, Water quality/Water chemistry, Others
Human factors	Climatic resources, Biological resources, Water resources, Ocean resource, Land resources, Agricultural resources, Mineral resources, Natural medicine resources, Tourism resources, Energy resources, Renewable resources, Environment pollution and control, Ecological degradation and protection, Natural disaster, population, Mobile big data, Industry, Agriculture, Labor force, Infrastructure, Social and economic, Boundary, Division, Traffic, Settlement, Others
Biology	Mammal, Bird, Fish, Insect, Reptile, Amphibian, Invertebrate, Seed plant, Algae, Bryophyte, Fern, Virus, Bacteria, Fungus, Others
Ocean	Marine meteorology, Marine biology, Marine ecology, Marine chemistry, Marine pollution, Marine acoustic and optical, Physical oceanography, Marine sediment, Submarine topography and geomorphology, Marine geophysics, Island and coastal zone, Marine remote sensing, Marine disaster, Others
Cryosphere	Glacier (Ice sheet), Frozen ground, Surface freeze-thaw cycle/state, Snow cover, River ice, Lake ice, Sea ice, Ice shelf, Iceberg, Ice crystal, Supercooled cloud water, Snowfall, Hail, Sleet, Others
Solid Earth	Rocks/Minerals, Formation, Paleontology, Paleoenvironment, Tectonics, Quaternary geology and geomorphology, Engineering geology, Environmental geology, Geologic hazard, Gravity, Geomagnetism, Earth resistivity, Geoheat, Seismology, Geochemistry, Sedimentary record, Others
Solar-terrestrial physics and astronomy	Extragalactic system and cosmos, Galactic system, Sun, Interplanetary space, Planet, Ionosphere, Middle and upper atmosphere, Geomagnetic field, Surface cosmic ray, Space weather events, Space environmental effect, Others
Earth observation	Satellite remote sensing, Aerial remote sensing, Ground observation, Others
Others	Others

The SDG classification, with the primary category focusing on the six SDG goals, including zero hunger, clean water and sanitation, sustainable cities and communities, climate action, life below water, life on land, and others, for a total of seven categories as the main dimensional content. The secondary categories were indicators within each SDG, described briefly, for a total of 60 indicators (Table 2).

Table 2. SDG classification used by the study.

Primary Category Name	Secondary Category Name
SDG2 Zero hunger	SDG2.1 End hunger, SDG2.2 End malnutrition, SDG2.3 Agricultural productivity and incomes, SDG2.4 Sustainable food production systems, SDG2.5 Genetic diversity, SDG2.a Investment, SDG2.b Trade, SDG2.c Food price
SDG6 Clean water and sanitation	SDG6.1 Drinking water, SDG6.2 Sanitation, SDG6.3 Water quality, SDG6.4 Water-use efficiency, SDG6.5 Integrated water resources management, SDG6.6 Water-related ecosystems, SDG6.a Water- and sanitation-related activities and programs, SDG6.b Water and sanitation management
SDG11 Sustainable cities and communities	SDG11.1 Housing, SDG11.2 Transport systems, SDG11.3 Sustainable urbanization, SDG11.4 World’s cultural and natural heritage, SDG11.5 Disasters, SDG11.6 Adverse environmental impacts, SDG11.7 Public spaces, SDG11.a Economic, social and environmental linkage, SDG11.b Disaster risk management, SDG11.c Buildings
SDG13 Climate action	SDG13.1 Climate-related hazards, SDG13.2 National policies, SDG13.3 Education, SDG13.a Green climate fund, SDG13.b Promote mechanisms
SDG14 Life below water	SDG14.1 Marine pollution, SDG14.2 Resilience, SDG14.3 Ocean acidification, SDG14.4 Harvesting, SDG14.5 Conserve coastal and marine areas, SDG14.6 Fisheries subsidies, SDG14.7 Sustainable use of marine resources, SDG14.a Marine biodiversity, SDG14.b Marine resources and markets, SDG14.c Conservation & sustainable use
SDG15 Life on land	SDG15.1 Terrestrial and inland freshwater ecosystems, SDG15.2 Sustainable management of forests, SDG15.3 Desertification, SDG15.4 Mountain ecosystems, SDG15.5 Biodiversity, SDG15.6 Genetic resources, SDG15.7 Illegal wildlife products, SDG15.8 Invasive alien species, SDG15.9 Ecosystem and biodiversity values, SDG15.a Financial resources, SDG15.b Finance sustainable forest management, SDG15.c Combat poaching and trafficking of protected species
Others	Others

Table 3. Comparison of word segmentation results.

Name	Precision	Recall	F-measure value
Chinese Academy of Sciences Word Segmentation System (NLPIR)	0.2982	0.3801	0.3342
Jieba participle	0.6545	0.7310	0.6906

Figure 2. Manual screening of high-frequency meaningless words.

Figure 3. High-frequency keywords for all data.

Figure 4. The discipline classification interface.

Figure 5. Sustainable Development Goals (SDG) classification interface.

Figure 6. Data label display interface.

Figure 7. Mapping Big Earth Data discipline classifications to SDG classification.

Data availability statement

Data sharing is not applicable to this article as no new data were created or analyzed in this study.