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Slot: Coordinate Reference System (CRS) (crs)

Coordinate reference system as an EPSG identifier or PROJ string. Mandatory. E.g. EPSG:4326 for Daymet, EPSG:5072 for NARR Lambert Conformal Conic.

Tier: core

Why this slot matters

Without the CRS the grid cannot be placed on the Earth correctly: the same coordinate pair points to different physical locations under different reference systems, so a mismatched or missing CRS silently shifts every location and attaches exposure values to the wrong places.

In plain terms

A coordinate reference system is the agreed way of turning numbers into places on the Earth — the same pair of coordinates means different spots under different systems. Naming the system (usually as a short EPSG code) tells software exactly which convention the numbers follow.

URI: envar:slot/crs

Applicable Classes

Name Description Modifies Slot
SpatialReference Spatial provenance of an environmental exposure value: the native grid / foot... yes

Properties

Type and Range

Property Value
Range String
Domain Of SpatialReference

Cardinality and Requirements

Property Value

Examples

Value
EPSG:4326

See Also

Identifier and Mapping Information

Annotations

property value
tier core
justification Without the CRS the grid cannot be placed on the Earth correctly: the same coordinate pair points to different physical locations under different reference systems, so a mismatched or missing CRS silently shifts every location and attaches exposure values to the wrong places.
explanation A coordinate reference system is the agreed way of turning numbers into places on the Earth — the same pair of coordinates means different spots under different systems. Naming the system (usually as a short EPSG code) tells software exactly which convention the numbers follow.
covered_by None

Schema Source

Mappings

Mapping Type Mapped Value
self envar:crs
native envar:crs

LinkML Source

name: crs
annotations:
  tier:
    tag: tier
    value: core
  justification:
    tag: justification
    value: 'Without the CRS the grid cannot be placed on the Earth correctly: the
      same coordinate pair points to different physical locations under different
      reference systems, so a mismatched or missing CRS silently shifts every location
      and attaches exposure values to the wrong places.'
  explanation:
    tag: explanation
    value: A coordinate reference system is the agreed way of turning numbers into
      places on the Earth — the same pair of coordinates means different spots under
      different systems. Naming the system (usually as a short EPSG code) tells software
      exactly which convention the numbers follow.
  covered_by:
    tag: covered_by
    annotations:
      omop_gaia:
        tag: omop_gaia
        annotations:
          extent:
            tag: extent
            value: full
          status:
            tag: status
            value: verified
          where:
            tag: where
            value: gaia_db data_source.srid (4326); gaia_catalog meta_etl_*.json epsg/local_epsg;
              location.geom EPSG:4326
          evidence:
            tag: evidence
            value: EnVar/examples/heat/COMPARISON.md §C (CRS of source raster ✅)
          note:
            tag: note
            value: GAIA carries the source-raster CRS first-class via data_source.srid,
              meta_etl epsg/local_epsg, and the enforced PostGIS geom SRID.
      degauss:
        tag: degauss
        annotations:
          extent:
            tag: extent
            value: absent
          status:
            tag: status
            value: asserted
          where:
            tag: where
            value: no column
          note:
            tag: note
            value: DeGAUSS leaves CRS implicit WGS84 with no column.
      amadeus:
        tag: amadeus
        annotations:
          extent:
            tag: extent
            value: full
          status:
            tag: status
            value: verified
          where:
            tag: where
            value: thredds_dataset.xml coordinate_system = "WGS84,EPSG:4326"
          evidence:
            tag: evidence
            value: EnVar/examples/heat/COMPARISON.md §C (CRS of source raster ✅)
          note:
            tag: note
            value: Amadeus's THREDDS grid declares the raster CRS explicitly as an
              EPSG code.
      cher:
        tag: cher
        annotations:
          extent:
            tag: extent
            value: absent
          status:
            tag: status
            value: asserted
          where:
            tag: where
            value: no column
          note:
            tag: note
            value: C-HER's metadata model (table_dictionary / column dictionary) documents
              spatial extent/resolution codes but no per-resource CRS/EPSG field.
      codata:
        tag: codata
        annotations:
          extent:
            tag: extent
            value: out_of_layer
          status:
            tag: status
            value: asserted
          where:
            tag: where
            value: no column
          note:
            tag: note
            value: CRS of a specific extract is an instance-layer representation detail;
              the conceptual EV/DDI-CDI layer does not carry it.
description: Coordinate reference system as an EPSG identifier or PROJ string. Mandatory.
  E.g. `EPSG:4326` for Daymet, `EPSG:5072` for NARR Lambert Conformal Conic.
title: Coordinate Reference System (CRS)
examples:
- value: EPSG:4326
  description: WGS 84, used by the Daymet and ACAG PM2.5 scenarios
from_schema: https://w3id.org/linkml/microschemas/envar
see_also:
- https://epsg.io/
- https://proj.org/
rank: 1000
domain_of:
- SpatialReference
range: string