Solar guide · Seasonal comparison
Brisbane Winter vs Summer Sun Path
Plan a three-time winter-versus-summer site observation in Brisbane using reproducible solar bearings, altitudes, and daylight data.
- Published
- Updated
Brisbane does not experience the extreme seasonal daylight swing of high-latitude cities, but the change is still large enough to alter facade exposure, shade depth, outdoor comfort, and the useful hours for direct sunlight. The difference is not only that summer days are longer: the daily arc also rises much higher in the sky.
This comparison holds latitude, longitude, timezone, and clock time constant. Only the date changes, so the table isolates the seasonal geometry rather than mixing it with a different site or timezone.
Why the northern sky matters in Brisbane
At Brisbane’s latitude, the midday Sun generally occupies the northern side of the sky. In winter it stays lower, so north-facing surfaces can receive useful direct light at a shallow angle. In summer the path climbs high enough that eaves and other horizontal shading can have a very different effect.
East-facing surfaces receive the early part of both arcs and west-facing surfaces receive the late part. The summer arc begins earlier and ends later, extending exposure on both sides of the day.
Separate clock time from solar shape
Queensland uses Australia/Brisbane time without daylight saving. This makes a fixed-clock comparison easier to read, but solar noon still need not be exactly 12:00. The highest point on the hourly chart can fall between samples.
For design questions, compare equivalent local times and also inspect each day’s sunrise and sunset boundaries. The two views answer different questions: clock-time conditions versus total available daylight.
These are fixed seasonal reference dates, not the exact local dates of the solstices or equinoxes.
Seasonal comparison
Brisbane seasonal reference 24-hour comparison
The same Brisbane coordinates and timezone are calculated for 21 June and 21 December 2026. The event summary and every whole-hour pair make the seasonal change inspectable instead of reducing it to a generic claim about longer summer days.
Calculated example — not a field measurement
A task you can reproduce
Choose three repeatable observation times for the same Brisbane outdoor space, then compare the astronomical baseline with what is actually visible on site.
- Observation point
- Brisbane, Queensland, Australia
- Coordinates
- -27.4698°, 153.0251°
- Timezone and model
- Australia/Brisbane · SPT-SUN-V1
- Reference dates
- 2026-06-212026-12-21
Three repeatable observation times
08:00
- June 21
- 53.1° North-east
- 14.8° altitude
- December 21
- 98.8° East
- 39.3° altitude
Morning check: compare whether the real eastern horizon admits direct light at each calculated height.
12:00
- June 21
- 357.0° North
- 39.0° altitude
- December 21
- 321.0° North-west
- 84.9° altitude
Clock-time check: 12:00 is a sample, while calculated solar noon is 11:50 in winter and 11:46 in summer.
16:00
- June 21
- 303.9° North-west
- 11.1° altitude
- December 21
- 258.7° West
- 33.1° altitude
Afternoon check: keep the viewpoint fixed and record which western obstacles intersect each calculated direction.
Reproduce the case
- 1. Open the Sun Path Map.
- 2. Enter the coordinates shown in the case inputs and select each listed seasonal reference date.
- 3. Inspect the solar bearing and altitude at 08:00, 12:00, and 16:00 without changing the observation point.
- 4. Use the same viewpoint and camera direction during each field visit.
- 5. Record actual obstructions and visible light beside the calculated baseline instead of treating the model as a shading survey.
Assumptions and stop conditions
- The observation point and camera direction stay fixed between the winter and summer visits.
- The solar engine reports an unobstructed astronomical baseline; it does not simulate indoor daylight, temperature, or shade from buildings, trees, terrain, and weather.
- 08:00, 12:00, and 16:00 are local clock-time samples. The calculated solar-noon event is reported separately.
Winter reference · 2026-06-21
- Sunrise
- 06:38
- Solar noon
- 11:50
- Sunset
- 17:02
- Day length
- 10h 24m
Summer reference · 2026-12-21
- Sunrise
- 04:50
- Solar noon
- 11:46
- Sunset
- 18:43
- Day length
- 13h 53m
Solar-noon altitude change
46.9° higher in December
Calculated daylight change
3.48 hours longer in December
| Time | June azimuth | June altitude | December azimuth | December altitude | Altitude delta |
|---|---|---|---|---|---|
| 00:00 | 149.5° | -85.3° | 175.8° | -39.0° | 46.4° |
| 01:00 | 100.3° | -73.6° | 158.8° | -36.0° | 37.6° |
| 02:00 | 90.4° | -60.4° | 144.3° | -29.7° | 30.7° |
| 03:00 | 84.3° | -47.1° | 132.6° | -20.8° | 26.3° |
| 04:00 | 79.0° | -34.0° | 123.4° | -10.3° | 23.6° |
| 05:00 | 73.7° | -21.0° | 115.9° | 1.3° | 22.3° |
| 06:00 | 67.9° | -8.5° | 109.6° | 13.5° | 22.0° |
| 07:00 | 61.2° | 3.6° | 104.1° | 26.3° | 22.7° |
| 08:00 | 53.1° | 14.8° | 98.8° | 39.3° | 24.5° |
| 09:00 | 43.0° | 24.7° | 93.4° | 52.5° | 27.9° |
| 10:00 | 30.1° | 32.6° | 86.4° | 65.8° | 33.2° |
| 11:00 | 14.5° | 37.7° | 71.3° | 78.9° | 41.2° |
| 12:00 | 357.0° | 39.0° | 321.0° | 84.9° | 45.8° |
| 13:00 | 339.9° | 36.4° | 279.4° | 72.8° | 36.5° |
| 14:00 | 325.2° | 30.2° | 270.0° | 59.6° | 29.4° |
| 15:00 | 313.3° | 21.5° | 264.0° | 46.3° | 24.8° |
| 16:00 | 303.9° | 11.1° | 258.7° | 33.1° | 22.1° |
| 17:00 | 296.4° | -0.5° | 253.4° | 20.2° | 20.7° |
| 18:00 | 290.0° | -12.7° | 247.5° | 7.7° | 20.4° |
| 19:00 | 284.4° | -25.4° | 240.8° | -4.3° | 21.1° |
| 20:00 | 279.2° | -38.4° | 232.5° | -15.4° | 23.0° |
| 21:00 | 273.8° | -51.6° | 222.2° | -25.2° | 26.4° |
| 22:00 | 266.9° | -64.9° | 209.3° | -33.0° | 31.9° |
| 23:00 | 253.1° | -78.0° | 193.4° | -37.9° | 40.2° |
Download the evidence dataset
Complete June and December 24-hour solar curves with event and day-length context. The UTF-8 CSV uses a fixed column order and contains calculated values only.
Practical reading for homes and outdoor spaces
A north-facing opening can be easier to shade from high summer sun while still admitting lower winter sun, but actual performance depends on overhang depth, sill height, surrounding obstacles, and the opening’s orientation. The solar path supplies the angle inputs; it does not complete the building-physics calculation.
For gardens and outdoor areas, winter results help identify locations that may lose direct light behind a fence or building. Summer results help identify prolonged western exposure and places where late-day shade may be valuable.
Responsible use
Practical uses and model limits
Terrain and buildings may be displayed in the 3D view for visual context where available. They are not inputs to the solar engine, which reports an unobstructed astronomical baseline without terrain, building, or tree shading.
Useful for
- • Comparing seasonal sunlight before choosing a courtyard or living-area orientation.
- • Selecting dates and times for a winter-versus-summer site-photo record.
- • Explaining why the same fixed shade structure behaves differently in June and December.
Do not overlook
- • The example uses level-horizon astronomy and does not simulate a particular house, eave, or window.
- • Fixed reference dates are seasonal anchors, not a complete annual energy or comfort model.
- • Cloud cover, surface temperatures, glazing properties, and reflected heat are outside the calculation.
Sources and reproducibility
Evidence and calculation sources
- USNO Astronomical Applications API documentation
External event-time reference documented in the site validation registry; USNO does not endorse this site.
- SunCalc
Solar position and astronomical event calculations used by this site.
- Luxon
IANA timezone-aware conversion between the selected local time and UTC.
- Solar Path Tracker methodology
Definitions, angle normalization, polar handling, precision, and model limits.