mc
short answer
essay
Prompt
[CHOICE] Advantages and disadvantages of moderate-resolution sensors (10 – 250 m), with examples.
Plain English answer (default view) — what you'd actually write on the test
**Moderate-resolution sensors** — the workhorses of regional and global Earth observation. Roughly **10 m to 250 m** per pixel. **Examples:** Landsat (30 m), Sentinel-2 (10 m), MODIS (250 m+). ### Advantages - **Wide swaths** — one pass covers an entire state. - **Frequent revisit** when you combine satellites — Landsat + Sentinel-2 ≈ every 2–3 days globally. - **Long free archives** — Landsat back to 1972, Sentinel-2 since 2015. - **Solid band selection** for vegetation indices, water indices, fire mapping. ### Disadvantages - **Can't see individual objects** — buildings, trees, single fields blur out. - **Mixed pixels** at edges — a 30 m pixel might be half-forest, half-grassland. - **Clouds wreck many scenes** — even with 16-day repeat, a lot of acquisitions are unusable. - **Thermal is coarser still** — Landsat thermal is 100 m, resampled to 30 m for display. The trade-off: you sacrifice fine detail for wide coverage and frequent revisit. For continental-scale science, that's the right trade.
🔬 Technical version / model bullets (revealed on click) — one bullet per line
Examples: Landsat OLI (30 m), Sentinel-2 MSI (10–60 m), MODIS (250–1000 m). **Advantages** Large swath — Landsat 185 km, Sentinel-2 290 km — regional/global coverage. Frequent revisit when combined (L8+L9+S2 ≈ every 2–3 days). Long free archives (Landsat → 1972). Multispectral breadth — NDVI, EVI, NBR, water indices. **Disadvantages** Can't resolve individual objects (buildings, small fields, trees). Mixed pixels at class boundaries hurt classification accuracy. Cloud contamination — 16-day repeat means many scenes unusable. Thermal resolution is coarser still (TIRS 100 m resampled to 30 m).
💡 Mnemonic / memory aid (shown on hover)
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