Semarang, Jawa Tengah
- Period
- 01 Jan 2026 — 01 Agu 2026212 days
- Datum
- Nol sensor stasiun (bukan MSL)
- gaps
- 3642 jam
- Source
- IOC Sea Level Station Monitoring Facility (UNESCO/IOC & VLIZ)
Source, licence and datum notes
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.
Methods
Method comparison
Residual RMS — Least squares
0.1751m
Residual RMS — Admiralty
0.1768m
Condition number κ — Least squares
1.52
| Constituent | H — Least squares | H — Admiralty | Difference H | g — Least squares | g — Admiralty | Difference g | Determination |
|---|---|---|---|---|---|---|---|
| K1 | 0.2123 | 0.2164 | -0.0041 | 67.9 | 69.7 | -1.8 | Direct |
| M2 | 0.0953 | 0.0946 | 0.0007 | 58.8 | 59.1 | -0.2 | Direct |
| S2 | 0.0757 | 0.0701 | 0.0056 | 307.1 | 309.9 | -2.8 | Direct |
| P1 | 0.0728 | 0.0716 | 0.0011 | 82.7 | 69.7 | 13.0 | Inferred |
| O1 | 0.0609 | 0.0629 | -0.0020 | 316.4 | 321.6 | -5.2 | Direct |
| N2 | 0.0385 | 0.0382 | 0.0004 | 27.3 | 22.9 | 4.4 | Direct |
| K2 | 0.0330 | 0.0189 | 0.0141 | 347.5 | 309.9 | 37.6 | Inferred |
| MS4 | 0.0045 | 0.0045 | -0.0000 | 169.2 | 172.6 | -3.4 | Direct |
| M4 | 0.0041 | 0.0045 | -0.0004 | 123.1 | 126.8 | -3.8 | Direct |
Admiralty infers K2, P1 from its neighbours through fixed ratios rather than solving for them. Least squares solves every constituent jointly and so accounts for the correlation between neighbours; that is the only fundamental difference between the two here.
The Admiralty implementation here is its projection-and-inference scheme, not a reproduction of the printed NP 159 tabulation and its filtering multipliers.