The main 3D result: conditions in the air at every grid cell and height.
Objects ( )
Marker showing what each cell is (air, building, plant, terrain). Used for display, not a measurement.
Flow u (m/s)
Wind speed component along the model's west–east (x) axis. Positive points east.
Flow v (m/s)
Wind speed component along the model's south–north (y) axis. Positive points north.
Flow w (m/s)
Vertical wind component. Positive means air rising, negative means sinking.
Wind Speed (m/s)
The overall wind speed (the three components combined). This is the value most people want when assessing wind comfort.
Wind Speed Change (%)
How much the local wind speed differs from the undisturbed inflow wind, as a percentage. Shows where buildings speed the wind up or slow it down.
Wind Direction (deg)
The compass direction the wind is coming from, in degrees (0/360 = North, 90 = East, 180 = South, 270 = West).
Pressure Perturbation (dPa)
The tiny local air-pressure differences buildings create as wind flows around them; it drives the wind pattern. Mostly of interest for flow analysis.
Potential Air Temperature (°C)
Air temperature (see Potential vs. real above). At pedestrian level read this as the air temperature in °C.
Air Temperature Delta (K)
The difference between the local air temperature and the inflow/reference air temperature; highlights warming (urban heat) or cooling (e.g. from greenery) caused by the design.
Air Temperature Change (K/h)
How fast the air temperature is rising or falling at that moment, in degrees per hour.
Specific Humidity (g/kg)
The actual amount of water vapour in the air (grams of water per kilogram of air). Unlike relative humidity it does not change just because the temperature changes.
Relative Humidity (%)
How close the air is to saturation (0–100%). This is the "humidity" people are used to from the weather forecast.
TKE (m²/s²)
Turbulent Kinetic Energy: how gusty/turbulent the air is. Higher near buildings and in the wind shadow behind them.
TKE Dissipation (m²/s³)
The rate at which turbulence is being damped out into heat. A technical companion to TKE.
Vertical Exchange Coef. Impuls (m²/s)
How strongly the air mixes momentum (and heat/moisture) in the vertical direction. Higher = better vertical mixing.
Horizontal Exchange Coef. Impuls (m²/s)
The same mixing strength, but in the horizontal direction.
Vegetation LAD (m²/m³)
Leaf Area Density: how much leaf surface is packed into each cubic metre of a plant at that cell. Higher = denser foliage, more shade and more cooling.
Direct SW Radiation (W/m²)
Direct sunlight reaching that cell (zero in shade). See Key concepts.
Diffuse SW Radiation (W/m²)
Scattered skylight reaching that cell (present even in shade).
Reflected SW Radiation (W/m²)
Sunlight bounced onto that cell from the ground and nearby surfaces.
Temperature Flux (K*m/s)
The rate at which heat is being carried through the air at that point. A process value used in the heat balance.
Vapour Flux (g/kg*m/s)
The rate at which water vapour (moisture) is being carried through the air at that point.
Water on Leaves (g/m²)
Dew or intercepted rain sitting on plant leaves, per square metre of leaf.
Leaf Temperature (°C)
The temperature of plant leaves at that cell, which can differ from the surrounding air.
Local Mixing Length (m)
A length scale describing the size of the turbulent eddies used in the model. A technical/internal value.
Mean Radiant Temp. (°C)
Mean Radiant Temperature (MRT) — the radiation "felt temperature" at that point (see Key concepts). Key for outdoor comfort.
TKE normalised 1D ( )
Turbulence compared against the undisturbed reference profile (dimensionless). Diagnostic.
Dissipation normalised 1D ( )
Turbulence dissipation compared against the reference profile. Diagnostic.
Km normalised 1D ( )
Mixing coefficient compared against the reference profile. Diagnostic.
TKE Mechanical Turbulence Prod. ( )
How much turbulence is being generated by wind shear around obstacles. Diagnostic.
Stomata Resistance (s/m)
How much the plant's leaf pores resist releasing water vapour; high values mean a stressed/closed plant transpiring (and cooling) less.
CO2 (mg/m3)
Carbon-dioxide concentration in the air, by mass.
CO2 (ppm)
The same CO₂ concentration expressed in parts per million (the unit usually quoted for air quality).
Plant CO2 Flux (mg/m²s)
The rate at which plants take up (or release) CO₂ through photosynthesis/respiration at that cell.
Div LW Radiation Temp Change (K/h)
How fast the air is heating or cooling purely because of longwave (heat) radiation exchange.
Natural convection velocity (m/s)
Gentle air movement driven by temperature differences (warm air rising) rather than by wind.
Building Number ( )
The ID of the building occupying that cell. An index, not a measurement.
The following appear only with certain settings/versions:
PET* Default Person (°C) — optional
Physiological Equivalent Temperature: the outdoor "feels-like" temperature for a standard person, combining air temperature, humidity, wind and radiation into one easy-to-read °C value.
UTCI (°C) — optional
Universal Thermal Climate Index: another widely used "feels-like" comfort index in °C, designed for outdoor conditions.
Spray source / concentration / evaporation / cooling — optional
Only with water spray (misting) systems: how much water is released, how much is in the air, how fast it evaporates, and how much it cools the air.