authority: folia
slug: curvature
name: Curvature
domain: land
subdomain: topography
authority_id: folia:curvature
parent: elevation
external_ids:
  cf_standard_name: null
canonical_units: m-1
external_validations:
  qgis:
    algorithm_id: sagang:slopelengthandsteepnessfactor
    docs_url: https://docs.qgis.org/latest/en/docs/user_manual/processing/algs/sagang/terrain_analysis_morphometry.html
  library:
    name: whitebox-tools
    id: Profile Curvature
    docs_url: https://www.whiteboxgeo.com/manual/wbt_book/available_tools/geomorphometric_analysis.html#ProfileCurvature
description: |
  Second derivative of the elevation surface — quantifies how the slope
  itself is changing. Two common variants: profile curvature (along
  the slope direction; positive = convex/ridge, negative = concave/valley)
  and planform curvature (across the slope direction; positive = diverging
  flow, negative = converging flow). Used by hydrology, erosion, and
  habitat-modelling ops.
theme: terrain
consumed_by: []
produced_by:
  - terrain_curvature
demos: []
status: documented
sources:
  - https://www.whiteboxgeo.com/manual/wbt_book/available_tools/geomorphometric_analysis.html
  - Zevenbergen and Thorne 1987, Earth Surface Processes and Landforms 12, 47-56