MODIS (Moderate Resolution Imaging Spectroradiometer) occupies a unique niche in the satellite ecosystem: it trades spatial resolution for temporal frequency and thematic breadth. While Sentinel-2 and Landsat provide sharper imagery, MODIS captures the entire Earth every 1–2 days across 36 spectral bands — and has been doing so continuously since 2000.
That combination of daily global coverage and a 25-year archive makes MODIS the go-to source for broad-scale monitoring where detecting change over time matters more than resolving fine spatial detail: seasonal vegetation cycles, continental fire patterns, snow extent dynamics, and ocean productivity trends all rely on MODIS data as their observational backbone.
What makes MODIS particularly accessible is that NASA distributes it as preprocessed, analysis-ready products rather than just raw imagery. Vegetation indices, land surface temperature, fire detections, snow cover, ocean color, and atmospheric measurements are all available as standardized composites that can be used directly without the calibration and atmospheric correction steps that raw satellite data typically requires.
This lowers the barrier to entry significantly — a vegetation time-series analysis that would require substantial preprocessing with Landsat imagery can start immediately with MODIS NDVI composites. For GIS workflows that need a long, consistent baseline of environmental observations at continental or global scale, MODIS remains the most complete record available.
