Geospatial Data Sources & Open Data
Free and open geospatial data from governments, international organizations, and communities makes professional-grade analysis accessible to everyone.
Theory & Foundations
The open data revolution has democratized geospatial analysis — petabytes of satellite imagery, global basemaps, and thematic datasets are freely available.
Satellite data portals: USGS Earth Explorer (Landsat, SRTM), Copernicus Open Access Hub (Sentinel), NASA Earthdata (MODIS, ICESat, GRACE), and Google Earth Engine (aggregated catalog).
Vector basemaps: OpenStreetMap (crowdsourced global features), Natural Earth (curated world boundaries), GADM (administrative boundaries for all countries).
Thematic data: WorldPop (population grids), CHIRPS (rainfall), ERA5 (climate reanalysis), Hansen GFC (forest change), JRC Global Surface Water.
National data: Bangladesh Bureau of Statistics (census), Survey of Bangladesh (topographic), SPARRSO (satellite), LGED (infrastructure).
In-Depth Coverage
Satellite Data Portals
Major archives providing free satellite imagery.
- USGS Earth Explorer: Landsat, SRTM, aerial photos
- Copernicus Open Access: Sentinel-1, 2, 3, 5P
- NASA Earthdata: MODIS, VIIRS, GRACE, SMAP
- GEE: Aggregated catalog of 70+ PB
Global Vector Datasets
Free basemap and boundary data.
- OpenStreetMap: Roads, buildings, POIs worldwide
- Natural Earth: Cultural and physical vectors at 3 scales
- GADM: Administrative boundaries for all countries
- GeoNames: Placenames database with coordinates
Key Techniques
Data Visualization
- 🛰️SatelliteLandsat, Sentinel, MODIS — free imagery
- 🗺️VectorOSM, Natural Earth, GADM — basemaps
- 📊ThematicWorldPop, CHIRPS, Hansen — specialized
Practical Workflow
- Define data requirements
- Search appropriate data portals
- Check data license and citation requirements
- Download in preferred format
- Inspect metadata and quality
- Reproject and clip to study area
- Validate against independent sources
- Document provenance in project
Software & Tools
Video Tutorials
Real-World Application
Real-World Projects
250K+ volunteers map crisis areas.
Case Study
Problem-Based Learning
Comprehensive flood risk assessment requires DEM, land cover, population, river network, and rainfall data.
Solution: DEM: SRTM 30m (USGS). Land cover: ESA WorldCover 10m. Population: WorldPop 100m. Rivers: HydroSHEDS/OSM. Rainfall: CHIRPS daily. Sentinel-1 SAR for flood history.