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
When should you inspect a Brisbane courtyard or garden for seasonal sunlight? Start with the same observation point at 08:00, 12:00, and 16:00 on the June and December reference dates. Check low winter light behind fences, high summer light around midday, and the western skyline in the afternoon. A single midday visit misses much of that difference.
The calculations below keep the Brisbane coordinates and timezone fixed. December has a higher arc and a longer astronomical daylight window, but the table cannot tell you how many direct-sun hours a particular garden receives. Use its bearings to decide where to look for obstructions on site.
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.
Check sunrise and sunset direction — Calculate the event times, daylight length, and bearings for the same location and date.
The June and December dates are fixed seasonal references, not the exact local dates of the solstices.
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
Explore the chart inputs: Load winter reference →Load summer reference →
Three repeatable observation times
08:00
Morning check: compare whether the real eastern horizon admits direct light at each calculated height.
12:00
Clock-time check: 12:00 is a sample, while calculated solar noon is 11:50 in winter and 11:46 in summer.
16:00
Afternoon check: keep the viewpoint fixed and record which western obstacles intersect each calculated direction.
Reproduce the case
- 1. Load the Brisbane June example.
- 2. The public reference coordinates, June date and Australia/Brisbane timezone load together. Use the December reference button to compare the same point.
- 3. Use the time-card links above to reproduce the exact 08:00, 12:00 and 16:00 angles in the angle calculator. The house tool uses its own 09:00 and 15:00 overview samples.
- 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
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
- • Astronomical day length is not the number of direct-sun hours at a home or garden. The calculation does not model windows, eaves, or local obstructions.
- • 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.