1Online spatial data sources
are websites, databases, portals, or online services that provide geographic/spatial data through the internet.
21. Government data portals
2. Open geographic databases
3. Satellite and remote sensing sources
4. Web mapping services
5. Global geographic datasets
6. Academicesearch repositories
Online spatial data sources can generally be grouped into:
3NAMRIA
National Mapping and Resource Information Authority
4NAMRIA
Provides or manages various geographic and mapping information for the Philippines.
5Geoportal Philippines
A government geographic information portal that provides access to Philippine geospatial datasets and services.
6Philippine Statistics Authority (PSA)
Provides statistical and demographic information that can be associated with geographic areas.
7OpenStreetMap
is a collaborative, open geographic database created and maintained by contributors around the world.
8OSM data
can be very useful, but quality and completeness can vary by location.
9Satellite imagery
provides images of Earth's surface collected by satellites.
10Sentinel satellites
Operated through the Copernicus Programme.
11Landsat
A long-running Earth observation program operated by the U.S. Geological Survey (USGS) and NASA.
12Digital Elevation Models (DEMs)
represent the elevation of Earth's surface digitally.
13Web Map Service (WMS)
allows GIS software to access map images from a remote server over the internet.
14WMS (Web Map Service)
Provides map images.
15WFS (Web Feature Service)
Provides geographic features/data, allowing the GIS user to work with individual features.
16WMTS (Web Map Tile Service)
Provides maps as pre-generated map tiles for efficient display.
17API (Application Programming Interface)
allows software applications to communicate with an online data service.
18GeoJSON
is a geographic data format based on JSON.
19Shapefile
is a commonly used vector GIS data format.
20•.shp — geometry
•.shx — shape index
•.dbf — attribute data
•.prj — coordinate reference system information
A shapefile is actually composed of multiple related files, commonly including:
21GeoTIFF
is a raster image format that stores geographiceoreferencing information within the file.
22Metadata
is information that describes a dataset.
23Accuracy
How close the data is to the actual location/value.
24Completeness
Whether all necessary features are included.
25Currency
How recently the data was updated.
26Resolution
The level of spatial detail.
27Consistency
Whether the data follows consistent standards.
28Positional accuracy
How accurately features are located geographically.
29Spatial resolution
describes the level of detail represented by spatial data, particularly raster data.
30Scale
describes the relationship between map distance and ground distance.
31Open data
Data that can generally be accessed and reused under a specified license.
32Restricted data
Data that may require:
•Permission
•Registration
•Payment
•Special authorization
33Attribution
means giving appropriate credit to the data source.
34Search → Evaluate → Download/Connect → Check → Process → Use
Common Online Spatial Data Workflow