Infrared - AI-Powered Environmental Simulations
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Knowledge Base

Find out about our models and how to use them

author
Alessandro
 · 14 min read

Understanding the climatic dashboard

Our comprehensive climate analysis dashboard provides location-specific environmental data through intuitive visualizations to help you make informed design decisions. The dashboard features Key Performance Indicators (KPIs) that quantitatively assess outdoor thermal conditions by analyzing the percentage of surface area exposed to different environmental factors.

Key metrics include horizontal infrared radiation for understanding radiative heat exchange, and detailed sun path analysis showing both Global Horizontal Radiation and Direct Normal Radiation. These data-driven insights enable you to optimize building performance, enhance outdoor comfort, and create climate-responsive urban spaces. Let’s explore each visualization in detail to unlock their full potential for your projects.

Horizontal infrared radiation

horizontal infrared radiation chart

  • Popup: Longwave radiation from the sky to horizontal surfaces. Supports analysis of radiative heat loss, facade performance, and nighttime cooling potential.

  • Description: These boxplots visualize the distribution of Horizontal Infrared Radiation (HIR) emitted by the atmosphere and received on horizontal surfaces.

  • Role: HIR is a critical factor in radiative heat exchange between the sky and building surfaces. Understanding its diurnal and seasonal variability supports key passive design strategies such as:

    • Thermal envelope performance towards thermal mass optimization
    • Façade design in terms of dynamic façade and shading responses
    • Nighttime radiative cooling (especially in warm climates where sky radiation dominates heat gain/loss)
  • KPIs

    • Monthly median HIR, capturing diurnal and seasonal variability
    • Daylight-hour HIR medians by month to support calibration of seasonal passive strategies
    • Correlation with sky cloudiness, informing envelope heat gain/loss behavior

Informed Sun Path

Global Horizontal Radiation (GHR)

global horizontal radiation chart

  • Popup: Visualizes the annual sun path overlaid with Global Horizontal Radiation intensity, helping to understand total solar energy received on flat surfaces.
  • Description: Combines solar azimuth and elevation angles with hourly GHI values to show the spatial and seasonal distribution of total incoming solar radiation on a horizontal plane.
  • Role: Supports decisions on PV panel potential, outdoor comfort strategies, and solar yield optimization.
  • KPIs:
    • Total annual GHI exposure
    • Seasonal intensity peaks
    • Daily sun arc correlation with energy input
    • Optimal façade or rooftop orientation for PV placement

Direct Normal Radiation (DNR)

direct normal radiation chart

  • Popup: Shows sun path colored by Direct Normal Radiation, revealing how intense and focused solar energy is when the sun is unobstructed.
  • Description: Maps the intensity of solar radiation received perpendicularly to the sun’s rays, helping assess direct solar gain potential and risks of overheating or glare.
  • Role: Crucial for concentrating solar systems, façade shading design, and glare control assessments.
  • KPIs:
    • Peak hours and directions of high DNI
    • Seasonal direct gain potential
    • Shading and solar glare risk zones
    • Optimization of vertical or tilted solar collectors

Diffuse Horizontal Radiation (DHR)

diffuse horizontal radiation chart

  • Popup: Displays the sun path with diffuse radiation values, useful for understanding solar input under cloudy or indirect conditions.
  • Description: Highlights how much solar energy reaches horizontal surfaces from the sky dome excluding direct sunlight, relevant for daylight design and energy modeling under overcast conditions.
  • Role: Informs daylight harvesting strategies, light shelf design, and uniform interior lighting assessments.
  • KPIs:
    • Diffuse light contribution over time
    • Seasonal variation of indirect radiation
    • Façade performance under non-sunny skies
    • Opportunities for glare-free daylighting

Horizontal Infrared Radiation (HIR)

horizontal infrared radiation chart

  • Popup: Visualizes the annual sun path enriched with longwave infrared radiation from the sky, important for understanding nighttime and passive heating dynamics.
  • Description: Illustrates thermal radiation received from the atmosphere, especially relevant during night or overcast conditions where longwave gains affect cooling loads.
  • Role: Helps evaluate building envelope heat exchange, roof surface cooling potential, and passive solar performance at night.
  • KPIs:
    • Nighttime radiation load
    • Seasonal thermal sky contribution
    • Envelope heat gain from the sky
    • Passive heating or radiative cooling potential

2D Projections

1. Orthographic Projection

ortographic projection

A vertical projection of the sky dome onto a horizontal plane. Commonly used in architecture, it visually represents the sun’s position in relation to the observer and is ideal for solar design and daylighting studies

2. Stereographic Projection

A mathematical projection that maps the celestial hemisphere onto a plane from the opposite pole. It preserves angular relationships (conformal) and is mainly used in astronomy, celestial navigation, and advanced solar geometry analysis. Stereographic projection

FeatureOrthographic ProjectionStereographic Projection
Projection typeVertical from zenith to groundFrom celestial pole onto a flat plane
Visual styleDome-like, natural-lookingFlat, mathematically even
Angle preservationNo (not conformal)Yes (conformal projection)
Sun path distortionSlightly distorted near horizonMore compressed near horizon
Common useArchitecture, daylighting, passive design - It is preferable for locations next to tropicals/equator worldwideAstronomy, celestial navigation, astrolabes - It is okay for locations next to poles
Horizon representationEdge of the circular diagramLower boundary of the projection
Tools using itLadybug Tools, Ecotect, Climate ConsultantCelestial mapping tools, astrolabe simulators

Solar Charts

Solar charts are the record of the solar trajectory for a complete year (although only some representative dates are plotted, such as equinoxes and solstices), based on the daily traces that it allows to mark on the celestial vault (which are projected on a polar plane) and for a given latitude.

solar charts

Thus, it is possible to link each human location to a given solar chart. It consists of the following parts:

  • a Cartesian coordinate system, which allows us to orient ourselves with respect to the cardinal points;

  • a circumference concentric to the origin of the coordinates (divided in 360º), which represents the theoretical horizon of the observer;

  • a system of virtual concentric rings, which indicate a height scale with respect to the theoretical horizon (with a maximum height of 90º at the origin);

  • daily curves, which indicate the solar path for certain days of the year; and finally, hourly curves, which allow us to identify the position of the sun at a certain time, when they intersect with the daily curves.

Analemmas

An analemma is a diagram showing the position of the Sun in the sky at the same hour of day (e.g., 9am) over the year, as seen from a fixed location on Earth.

  • It typically has a figure-eight shape.
  • The shape results from two main factors:
    1. Earth’s axial tilt (~23.5°)
    2. Earth’s elliptical orbit (not a perfect circle)

analemma

In sun path diagrams, the analemma helps visualize how:

  • The solar altitude (height of the sun) and
  • The solar azimuth (sun’s compass direction)

change throughout the year at a given location.

In practic (e.g., architecture, solar studies):

  • Sun path diagrams often include analemmas for different times of the day.
  • They help determine sunlight exposure, shading design, and solar energy potential at specific times and dates.

Solar trajectory

solar trajectory

Two coordinates are used to fix the position of the sun on the celestial vault at a given point in its path: altitude and azimuth.

  • The altitude indicates the vertical angle of the sun with respect to the theoretical horizon line;
  • The azimuth is the angle of the sun above the horizon measured with respect to the exact north. image10

Legend:

  • a = celestial vault
  • b = horizontal plane
  • c = parabolic projection surface
  • d = sun path on any given date
  • e = projection of the sun path on the parabolic surface
  • f = meridian
  • g = geographic north
  • h = projection of the parabolic surface onto a horizontal surface: sun chart

Solar Radiation + Cloud Coverage

solar radiation cloud coverage

  • Popup: Compares sky cover with solar radiation. Helps evaluate daylight access and photovoltaic potential under clear, intermediate, and cloudy skies.

This composite visualization links cloud cover patterns to solar availability through monthly averaged profiles. Clear, intermediate, and cloudy sky categories are overlaid with radiation curves, enabling a nuanced reading of how much solar energy is actually available across different sky conditions.

  • Description: Overlaid chart combining stacked bars of sky cover classification (clear, intermediate, cloudy) with monthly diurnal trends of global, direct and diffuse radiation.
  • Role: Guides decisions on daylighting, PV feasibility, and shading needs by analyzing sky clarity and solar gains together.
  • KPIs:
    • Distribution of clear, intermediate, and cloudy skies
    • Monthly solar intensity profiles
    • Impact of cloudiness on global vs direct vs diffuse radiation ratio

Temperature & Humidity Panel

Dry Bulb Temperature

dry bulb temperature chart 1 dry bulb temperature chart 2 image13

  • Popup: Shows outdoor air temperature trends. Supports thermal comfort analysis, energy modeling, and passive heating/cooling design.

Understanding the ambient air temperature is fundamental for climate-responsive design. These visualizations combine a yearly view (average and daily range) with hourly profiles across months, offering both strategic and operational insights. This helps assess thermal comfort, determine passive cooling/heating opportunities, and calibrate energy models.

  • Description: Visualizes the ambient air temperature over time, excluding moisture, through an annual trend of daily min–max and monthly diurnal profiles showing hourly variation.
  • Role: Serves as a baseline for evaluating thermal comfort, building energy demand, and the suitability of passive design strategies.
  • KPIs:
    • Seasonal average, maximum, and minimum temperatures
    • Frequency of extreme temperature events
    • Hourly temperature trends and diurnal range across the year

Relative Humidity

relative humidity chart 1 relative humidity chart 2

  • Popup: Shows moisture levels across the year. Key for comfort assessment, condensation risk, and humidity control strategies.

Relative humidity plays a crucial role in thermal comfort, condensation risk, and envelope performance. This dual-panel view combines annual averages with fine-grain diurnal behavior, enabling designers to identify humid peaks, potential comfort challenges, and extimate further HVAC dehumidification needs.

  • Description: Depicts the proportion of moisture in the air relative to saturation, via both daily seasonal trends and hourly monthly profiles.
  • Role: Critical for assessing indoor comfort, potential condensation risks, and the performance of passive or HVAC-based humidity control strategies.
  • KPIs:
    • Daily and seasonal average, maximum, and minimum RH
    • Occurrence of low (< 30%) and high (> 80%) humidity events
    • Diurnal RH variations and timing of daily peaks

Wind Panel

Wind Rose

wind rose chart

  • Popup: Polar plot showing wind frequency and speed distribution by direction. Supports assessment of dominant airflow patterns, outdoor comfort, and natural ventilation potential.

This wind rose diagram visualizes the directional distribution of wind over a defined period (typically annual or seasonal). Each sector represents a compass direction (e.g., N, NE, E, etc.), with the radial extent showing how frequently winds arrive from that direction. The stacked color bands within each sector correspond to discrete wind speed classes, indicating not only where the wind comes from, but also how strong it tends to be.

  • Description: Directional wind frequency diagram with eight sectors (N, NE, E, SE, S, SW, W, NW), discretized by wind speed intervals ranging from calm (less than 0.5 m/s) to strong winds (greater than 20.7 m/s). Frequencies are shown as percentages over the total observations, giving insight into both wind dominance and variability.
  • Role: Supports urban wind comfort analysis (e.g. Lawson criteria), pollutant dispersion modeling, passive ventilation planning, and climate-sensitive design by identifying dominant wind corridors and recurring speed thresholds.
  • KPIs (location-dependent):
    • Dominant wind direction(s) with the highest cumulative frequency
    • Prevailing wind speed rang(es) across all directions
    • Peak directional frequency percentage observed for any single direction
    • Wind calmness or turbulence, proportion of low-speed ( < 1.5 m/s) vs high-speed (> 10 m/s) winds
    • Active directional diversity, in number, those with significant wind frequency

Wind Speed

wind speed chart

  • Popup: Hourly wind speed distribution over the year. Useful for air recycle strategies, outdoor comfort, and wind-sensitive elements.

Wind speed patterns vary not only with season but also by time of day, influencing ventilation performance, thermal comfort, and structural wind loads. This matrix allows designers to identify wind-rich hours and calm periods with high temporal granularity.

  • Description: Hourly matrix showing the intensity of wind speed (m/s) across each day of the year, using color gradients to encode values.
  • Role: Helps detect optimal periods for passive cooling, assess risk of wind discomfort, and guide placement of wind-sensitive elements.
  • KPIs:
    • Diurnal wind speed variation and seasonal cycles
    • Seasonal occurrence of low (< 1.5 m/s) and high (> 6 m/s) wind speeds
    • Identification of high-wind hours for design adaptation

Day/Night Panel

Diurnal Climate Graphs (Day vs Night)

diurnal climate charts

  • Popup: Hourly profiles of key variables split by day and night. Supports envelope tuning, façade design and passive strategy timing.

These detailed diurnal charts visualize six environmental variables over 24 hours, split between day and night. This allows for granular understanding of how conditions shift throughout the day, supporting strategies like night ventilation, shading timing, and smart envelope tuning.

  • Description: Multi-variable dashboard comparing hourly profiles of temperature, humidity, solar radiation, wind, cloud cover, and albedo across 24 hours for a selected day, split into daytime and nighttime bars.
  • Role: Enables precise identification of climate stressor by supporting hourly decision-making for passive design, thermal comfort calibration, and facade/material strategies.
  • KPIs:
    • Day vs night profiles for key environmental variables
    • Albedo and sky cover influence on daily microclimate dynamics
    • Detection of peak exposure hours

Comfort Panel

Universal Thermal Climate Index (UTCI)

Hourly UTCI Heatmap

hourly utci chart

  • Popup: Hourly thermal comfort index from air temperature, wind, humidity, and radiation. Identifies stress periods and informs outdoor comfort planning and heat mitigation.

The Universal Thermal Climate Index (UTCI) provides a dynamic holistic indicator that combines the effects of air temperature, wind speed, humidity, and mean radiant temperature (solar exposure) to evaluate outdoor thermal stress on the human body. This hourly matrix visualizes the intensity of thermal stress over time, helping identify when and how often people are exposed to discomfort in outdoor spaces.

  • Description: Displays hourly UTCI values across the entire year, capturing short-term and seasonal variations in thermal comfort conditions.
  • Role: Supports climate-responsive urban design by identifying critical exposure periods of thermal discomfort, aiming to mitigate heat stress and improve liveability, by informing mitigation strategies such as shading, ventilation and vegetation.
  • KPIs:
    • Hour-by-hour UTCI values reveal when outdoor spaces become physiologically stressful
    • Frequency and intensity of heat or cold stress periods
    • Temporal analysis of thermal comfort challenges by hour and season

Hourly UTCI Thermal Stress Categories

hourly utci thermal stress chart

  • Popup: Hourly thermal stress categories. Supports detection of discomfort periods and guides mitigation strategies in outdoor spaces.

This categorized heatmap shows the perceived thermal stress levels according to the official UTCI classification scale - from extreme cold stress to extreme heat stress. Each cell represents the qualitative comfort condition for a specific hour and day throughout the entire year, helping to identify recurring patterns and critical periods.

  • Description: Hourly heatmap color-coded by UTCI stress category, enabling a quick visual interpretation of thermal comfort conditions across the year.
  • Role: Highlights the most critical hours for thermal discomfort, supporting targeted microclimatic interventions such as passive shading, cooling strategies, or reflective materials in outdoor spaces.
  • KPIs:
    • Hourly frequency of each UTCI stress category
    • Temporal distribution of high-risk and no thermal stress periods
    • Visual identification of hours of the year with the highest impact on outdoor comfort and public health

Hourly UTCI Comfortable Category

hourly utci comfortable chart

  • Popup: Hours of the year within thermophysiologically defined comfort conditions based on UTCI. Supports assessment of urban outdoor usability and passive design planning.

This matrix displays only the hours classified as thermally comfortable based on the Universal Thermal Climate Index (UTCI). The visualization distinguishes between:

  • Moderate Comfort Zone (9°C ≤ UTCI < 18°C), within ‘No Thermal Stress’ Category as defined by the UTCI classification scheme;
  • Optimal Comfort Zone (18°C ≤ UTCI ≤ 26°C), within ‘No Thermal Stress’ UTCI Category, but aligned with the ‘Thermal Comfort Zone (TCZ)’ as defined by the International Union of Physiological Sciences (2003) — a state in which a human subject expresses indifference to the thermal environment, under stable mean radiant temperature, humidity, and air movement.

Following Bröde et al. (2012a) and recent validation studies, the 18–26 °C UTCI subinterval is considered the most appropriate reference for urban outdoor comfort assessments, due to its stronger physiological basis.

  • Description: Hourly matrix highlighting only the periods within UTCI-defined comfort zones, emphasizing both moderate and optimal outdoor thermal conditions throughout the year.
  • Role: Informs climate-sensitive urban design, environmental policy, and public space programming by identifying diurnal and seasonal patterns of natural outdoor thermal comfort.
  • KPIs:
    • Hourly occurrence of UTCI within comfort zones (moderate and optimal)
    • Identification of spatial and temporal patterns of favorable thermal environments
    • Proportion of “usable” hours in urban open spaces under passive conditions

Hourly UTCI Thermal Stress Distribution

hourly utci thermal stress

  • Popup: Monthly percentage of hours in each UTCI stress category. Highlights seasonal comfort trends and high-risk exposure levels.

To complement the hourly matrices, this stacked bar chart summarizes monthly thermal stress exposure using UTCI classification levels. It offers a clean overview of seasonal shifts in outdoor comfort and highlights opportunities for passive design strategies and public space adaptation.

  • Description: Monthly stacked bar chart showing the percentage of hours in each UTCI stress category, from extreme cold to extreme heat.
  • Role: Identifies seasonal patterns of thermal stress.
  • KPIs:
    • Proportion of hours in each UTCI stress category
    • Monthly trends in outdoor thermal stress levels
    • Severity of seasonal discomfort and mitigation potential

Degree Days (HDD/CDD)

degree days chart

  • Popup: Estimates seasonal heating and cooling needs based on outdoor temperatures. Supports energy modeling and HVAC sizing.

Heating and Cooling Degree Days illustrates the cumulative temperature difference between outdoor air temperatures and a defined base temperature (e.g., 18°C for CDD, 10°C for HDD) across a given time period.

  • Description: The graph quantifies the extent and duration of temperature deviations, representing the theoretical energy demand for space heating (HDD) or cooling (CDD).
  • Role: Serves as a key indicator for estimating HVAC energy loads and supporting thermal comfort optimization strategies.
  • KPIs:
    • Total Annual HDD/CDD values
    • Monthly variability and energy demand peaks
    • Comparison of heating vs cooling load distribution
  • Knoledge base

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