Kolinamil, Pelabuhan Jakarta
Diurnal- Period
- 10 Jan 2026 — 31 Jul 2026202 days
- Datum
- Nol sensor stasiun (bukan MSL)
- gaps
- 68740 jam
- Source
- IOC Sea Level Station Monitoring Facility (UNESCO/IOC & VLIZ)
Source, licence and datum notes
IOC menyajikan data mentah terhadap nol sensor masing-masing stasiun. Tinggi di sini tidak merujuk MSL, LAT, maupun chart datum.
Licence: Akses terbuka dengan kewajiban sitasi (VLIZ/IOC, DOI 10.14284/482)
Flanders Marine Institute (VLIZ); Intergovernmental Oceanographic Commission (IOC) (2026): Sea level station monitoring facility. https://www.ioc-sealevelmonitoring.org — DOI 10.14284/482
Not for navigationThe official Indonesian tide tables are published by Pushidrosal.
The chart
The record
- Observed the water level the gauge actually recorded
- Predicted what the fitted constituents say it should be
- Residual the difference — weather, wind and instrument trouble
The rest is held out and predicted. Shorten the window and constituents start dropping out — the same Rayleigh criterion, moved by the window rather than by the length of the record.
Result
Request refused
S2 and K2 cannot be separated on a record of 135.0 days.
- S2 and K2 differ by only 0.0821°/h: separating them needs a record of 182.6 days, and 135.0 are available.
- K1 and P1 differ by only 0.0821°/h: separating them needs a record of 182.6 days, and 135.0 are available.
Record length: 135.0 days · Length required: 182.6 days
What follows is the largest set this window can still support: M2, S2, N2, K1, O1, Q1, M4, MS4.
- Condition number κ
- 1.49good
- Residual RMS
- 0.1018 m
- Mean level Z₀
- 0.6374 m
- Record length
- 135.0 days
Unexplained, over the fitted part
0.1018m
Mean distance between the black line and the blue one, over the part used to fit.
Unexplained, over the held-out part
0.1054m
Over the part deliberately not seen while fitting. This is the real test.
Constituents
Harmonic constituents
| Constituent | Amplitude H (m) | Phase g (°) | Lag (h) | Speed (°/h) | Period (h) | Nodal factor f | Nodal correction u (°) |
|---|---|---|---|---|---|---|---|
| K1165.555 | 0.2359±0.0025 | 213.7±0.6 | 14.21 | 15.041069 | 23.934 | 1.1066 | 2.90 |
| O1145.555 | 0.1439±0.0023 | 203.6±0.9 | 14.60 | 13.943036 | 25.819 | 1.1725 | -3.27 |
| M2255.555 | 0.0702±0.0028 | 133.0±2.3 | 4.59 | 28.984104 | 12.421 | 0.9659 | 0.80 |
| S2273.555 | 0.0567±0.0027 | 83.5±2.8 | 2.78 | 30.000000 | 12.000 | 1.0000 | 0.00 |
| Q1135.655 | 0.0343±0.0023 | 191.0±3.9 | 14.25 | 13.398661 | 26.868 | 1.1725 | -3.27 |
| N2245.655 | 0.0179±0.0028 | 91.3±9.0 | 3.21 | 28.439730 | 12.658 | 0.9659 | 0.80 |
| MS4473.555 | 0.0068±0.0028 | 157.9±23.7 | 2.68 | 58.984104 | 6.103 | 0.9659 | 0.80 |
| M4455.555 | 0.0057±0.0029 | 124.2±29.7 | 2.14 | 57.968208 | 6.210 | 0.9330 | 1.60 |
H is half the height of that constituent’s wave; g is how late it arrives behind the Moon or Sun, and the column beside it says the same thing in hours — g divided by the constituent’s speed. f and u are the 18.6-year corrections, applied and still shown.
The ± figure is one standard error, taken from the diagonal of the solve’s covariance matrix. It assumes the record’s noise is independent from hour to hour, and tidal residuals are not: weather lasts for days, so neighbouring hours are wrong in the same direction. The true uncertainty is larger than what is printed here — by how much, this site does not compute.
A property of the place, or of these months?
The same numbers, four different stretches of the record
This whole site rests on one claim: that amplitude and phase are properties of the place — what a coastline does to the same forcing. But every number above came from one particular stretch of 2026. Here the record is cut into 4 equal, non-overlapping pieces and each is fitted on its own. Where an amplitude barely moves between them it is behaving like a property of the harbour. Where it swings, the record is doing the work rather than the place.
- Stretch 1 10 Jan 2026 — 01 Mar 2026
- Stretch 2 01 Mar 2026 — 21 Apr 2026
- Stretch 3 21 Apr 2026 — 10 Jun 2026
- Stretch 4 10 Jun 2026 — 31 Jul 2026
| Constituent | Mean H (m) | Lowest — highest | Swing | Phase swing |
|---|---|---|---|---|
| K1 | 0.2591 | 0.2092 — 0.2947 | 33% | ±14.6° |
| O1 | 0.1449 | 0.1359 — 0.1494 | 9% | ±1.9° |
| M2 | 0.0705 | 0.0636 — 0.0818 | 26% | ±27.1° |
| S2 | 0.0576 | 0.0395 — 0.0868 | 82% | ±40.4° |
| Q1 | 0.0359 | 0.0316 — 0.0413 | 27% | ±10.5° |
| N2 | 0.0228 | 0.0156 — 0.0344 | 83% | ±34.3° |
| MS4 | 0.0067 | 0.0035 — 0.0099 | 96% | ±43.4° |
| M4 | 0.0065 | 0.0048 — 0.0095 | 71% | ±38.5° |
One constituent, from the start
How K1 came out of this record
The table above is the answer. This is the route to it, in this record’s own numbers — nothing simplified or rounded for the example.
- Step 1 — Where the Moon and Sun are. Every constituent has six Doodson numbers saying how many times each astronomical element enters its angle. For K1 they are 1 1 0 0 0 0, so its equilibrium argument is V(t) = τ + s − 90°. The element polynomials are from Meeus, Astronomical Algorithms (2nd ed.), chapters 22 and 47.
τ = mean lunar time · s = the Moon’s mean longitude · h = the Sun’s mean longitude · p = lunar perigee · N = the Moon’s ascending node · p′ = solar perigee.
Step 2 — Two columns, hour by hour. cos(V + u) and sin(V + u) are evaluated at every sample in the record. These are K1’s two columns of the design matrix; four consecutive hours of this record:
How K1 came out of this record Time (UTC) V(t)° cos(V+u) sin(V+u) K1’s share (m) Recorded (m) 28 Mar 2026 10:00 UTC 65.84 0.3626 0.9319 -0.2138 0.2670 28 Mar 2026 11:00 UTC 80.88 0.1084 0.9941 -0.1676 0.4110 28 Mar 2026 12:00 UTC 95.93 -0.1533 0.9882 -0.1100 0.5190 28 Mar 2026 13:00 UTC 110.97 -0.4045 0.9145 -0.0447 0.5760 - Step 3 — Least squares picks one pair of numbers. The solve looks for the a and b that bring Σ (a·cos + b·sin) as close to the record as it can get, for every constituent at once. For K1 it returned a = -0.2171 and b = -0.1450. The last column above is a·cos + b·sin: what K1 alone contributes at that hour.
- Step 4 — Two lines of trigonometry. The pair (a, b) is amplitude and phase in another form: H = √(a² + b²) ÷ f = 0.2359 m, and g = atan2(b, a) = 213.7°. Exactly the numbers on K1’s row above. The division by f takes out the 18.6-year nodal correction, so the constant does not depend on which year you happened to observe.