Surabaya, Jawa Timur
- Period
- 01 Jan 2026 — 01 Agu 2026212 days
- Datum
- Nol sensor stasiun (bukan MSL)
- gaps
- 7891 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
0.1064m
Residual RMS — Admiralty
0.1120m
Condition number κ — Least squares
1.52
| Constituent | H — Least squares | H — Admiralty | Difference H | g — Least squares | g — Admiralty | Difference g | Determination |
|---|---|---|---|---|---|---|---|
| K1 | 0.4755 | 0.4906 | -0.0151 | 24.3 | 26.0 | -1.6 | Direct |
| M2 | 0.3769 | 0.3794 | -0.0025 | 119.0 | 119.7 | -0.8 | Direct |
| O1 | 0.2707 | 0.2831 | -0.0124 | 347.7 | 347.3 | 0.4 | Direct |
| S2 | 0.2242 | 0.2255 | -0.0013 | 129.6 | 132.1 | -2.5 | Direct |
| P1 | 0.1308 | 0.1624 | -0.0316 | 25.2 | 26.0 | -0.8 | Inferred |
| N2 | 0.0731 | 0.0672 | 0.0058 | 106.2 | 96.5 | 9.7 | Direct |
| K2 | 0.0705 | 0.0609 | 0.0096 | 125.8 | 132.1 | -6.2 | Inferred |
| MS4 | 0.0213 | 0.0209 | 0.0005 | 200.6 | 203.7 | -3.1 | Direct |
| M4 | 0.0210 | 0.0212 | -0.0002 | 198.8 | 199.2 | -0.4 | 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.