Coordinate Reference System (CRS)
Definition
The mathematical framework defining how coordinates relate to real-world positions on the Earth's surface. All layers in a forensic GIS must share a common CRS to overlay correctly. Mixing CRS without reprojection produces alignment errors that can misplace anomaly positions by metres or more.
- Function
- Relates coordinates to real-world Earth positions
- Requirement
- Must be shared across all GIS layers
- Failure mode
- Misaligned features, mislocated anomalies
Common questions
What happens if two GIS layers use different coordinate reference systems without reprojection?+
Features from each layer render offset from one another, which can misplace a search boundary or an anomaly location by metres or more even though each layer looks internally consistent.
Why does coordinate reference system consistency matter specifically for search management?+
Accurate overlay of drone imagery, ground-penetrating radar hits, and search-team GPS tracks all depend on a shared CRS, and a mismatch could direct a search team to dig in the wrong location.
Related terms
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