SWEET Ontology
type: Ontology
version info: 2.3
imports: state.owl
imports: statePhysical.owl
imports: reprSpaceGeometry3D.owl
imports: matrWater.owl
imports: realmAstroBody.owl
imports: relaSpace.owl
imports: relaChemical.owl
imports: rela.owl
imports: matrCompound.owl
imports: reprSpaceGeometry.owl

Geosphere
type: Class
subclass of: PlanetaryRealm
subclass of: Restriction
  on property: hasState
  has value: Solid
subclass of: Restriction
  all values from: PlanetarySurface
  on property: hasUpperBoundary
comment: The term Geosphere is often used to refer to the densest (solid) parts of a planet, which consist mostly of rock and regolith [Wikipedia]

Hydrosphere
type: Class
subclass of: PlanetaryRealm
subclass of: Restriction
  on property: hasSubstance
  has value: Water
comment: A hydrosphere in physical geography describes the combined mass of water found on, under, and over the surface of a planet. [Wikipedia]

Land
type: Class
subclass of: Geosphere
subclass of: Restriction
  on property: hasState
  has value: Solid
comment: The part of a planetary surface that is a solid

Ocean
type: Class
subclass of: Hydrosphere
subclass of: Restriction
  on property: hasState
  has value: Liquid
subclass of: Restriction
  all values from: PlanetarySurface
  on property: hasUpperBoundary
comment: An ocean is a major body of saline water, and a principal component of the hydrosphere. [Wikipedia]

Atmosphere
type: Class
subclass of: PlanetaryRealm
subclass of: Restriction
  on property: hasState
  has value: Gas
subclass of: Restriction
  all values from: PlanetarySurface
  on property: hasLowerBoundary
comment: An atmosphere is a layer of gases that may surround a material body of sufficient mass,[1] by the gravity of the body, and are retained for a longer duration if gravity is high and the atmosphere's temperature is low. [Wikipedia]

Cryosphere
type: Class
subclass of: Hydrosphere
subclass of: Restriction
  on property: hasSubstance
  all values from: Ice
subclass of: Restriction
  all values from: PlanetarySurface
  on property: hasUpperBoundary
comment: The cryosphere collectively describes the portions of a planetary surface in frozen form, including sea ice, lake ice, river ice, snow cover, glaciers, ice caps and ice sheets, and frozen ground (which includes permafrost). [Wikipedia]

PlanetarySurface
type: Class
subclass of: PlanetarySurfaceLevel
equivalent class: Subaerial
comment: The surface of the planet defined by solid and/or liquid layers

PlanetarySurfaceLevel
type: Class
subclass of: Surface
equivalent class: PlanetaryBoundary
subclass of: CriticalZone
comment: A qusai-horizontal surface spanning all or part of a planet that corresponds to a constant value of some parameter