Essay — Applications of the Landsat series.

• Continuity (since 1972) enables decadal change detection unmatched by any other system.
• Land-cover & land-use change. Deforestation (Amazon, Southeast Asia), urban growth, wetland loss.
• Agriculture. Crop-type mapping, yield forecasting via NDVI time series, irrigation monitoring.
• Water. Reservoir extent, glacier retreat, algal blooms (using thermal + VSWIR).
• Disaster response. Wildfire burn-scar mapping, flood extent, volcanic activity.
• Climate. Long-term surface-temperature records, snow-cover trends.
• Free & open data policy (since 2008) — the single biggest multiplier of Landsat’s impact.