Model attributes (Heat Overlay)

The heat overlay's model calculations depend on a number of calculation-wide parameters. These parameters are available as attributes of the heat overlay and can be modified as such.

Attribute	Unit	Description
AVERAGED_LAST_RESULT	boolean	Whether to ignore the date-time setting for the last calculated timeframe, and show an average of the results of all preceding timeframes instead.
DAILY_AVG_RADIATION	Wm-2 / hr	The average of amount of sun radiation per hour per square meter for this day, measured at a weather station.
DAILY_AVG_WIND_SPEED	m/s	The daily average wind speed measured at a weather station at the height of 10 meters above ground.
DAILY_TEMPERATURE_MAX	°C	Maximum temperature measured at a weather station.
DAILY_TEMPERATURE_MIN	°C	Minimum temperature measured at a weather station.
DATES	timestamp	Dates define the amount of timeframes and are used to define the day and time for calculating sun angles.
EXCLUDE_BUILDINGS	boolean	Whether the results of buildings should be excluded from the final results.
EXCLUDE_WATER	boolean	Whether the results at the location of water should be excluded from the final results.
FOLIAGE_AREAS	boolean	Whether to use foliage data from Areas instead of the calculated foliage decks from functions with a foliage crown factor.
HOURLY_HUMIDITY	percentage	The relative humidity of the air at this hour, measured at a weather station.
HOURLY_RADIATION	Wm-2 / hr	The amount of Sun radiation this hour, measured at a weather station.
HOURLY_TEMPERATURE	°C	The temperature at this hour, measured at a weather station.
SUN_ALTITUDE	°	The sun angle up from the horizon.
SUN_AZIMUTH	Geo angle	The angle along the horizon, with 0° corresponding to north, and increasing in a clockwise fashion
SUN_DAILY_MOTION	factor	A factor used in calculating the Atmospheric Temperature from the calculated Urban Heat Island value.
WIND_DIRECTION	Geo angle	The wind direction viewed from above, with 0° corresponding to north, and increasing in a clockwise fashion.
WIND_SPEED	m/s	The wind speed measured at a weather station at the height of 10 meters above ground.

Notes

• The model relies on a number of attributes which can be measured by measure stations. For any given project, it is recommended to find data from a (reference) weather station applicable to the project area, and use those values as parameters for the Heat Module calculations.
• When the DATES attribute is configured for multiple timeframes, the Hourly, Sun, and Wind attributes should have an equal amount of entries. When using the Heat Overlay configuration wizard, the necessary entries are created automatically.

See also

• Weather station

---

Heat Module

Heat Module

Tutorials

Overview

Theory

Benchmarks

Group

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

Prequels

Building elevation • Foliage height • Terrain elevation

Related

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