Terrain bowen ratio (Heat Overlay)

The Bowen ratio is a property of a surface, specifically the ratio between two types of heat transfer (sensible heat and latent heat). The wetter the surface, the lower the ratio.

Notes

• The DPRA Heat stress report uses only two possible values for the Bowen ratio: 0.4 and 3.0.
• Terrains such as grassland and functions such as trees and vegetation generally have a ratio of 0.4. Other terrains and functions have a ratio of 3.0.
• Water is special in the sense that during the day the ratio is 0.4 and at night the ratio is 3.0.

See also

• Bowen ratio
• Bowen ratio overlay result
• PET formulas

References

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Model attributes

Model attributes

Daily average radiation • Daily average wind speed • Daily maximum temperature • Daily minimum temperature • Dates • Exclude buildings • Exclude water • Exclude foliage height m • Foliage areas • Hourly humidity • Hourly radiation • Hourly temperature • Max shadow distance • Sun altitude • Sun azimuth • Sun daily motion • Wind direction • Wind speed • Wind decline angle

Building attributes

Bowen ratio • Foliage height • Foliage crown factor • Vegetation fraction

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Building elevation • Foliage height • Terrain elevation

Related

Calculation models and formulas • Feature attributes • Model attributes • Result types

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