GLOSS Station Handbook
Station information sheet
| General | |
| GLOSS number | 149 |
| Station name | Apra Hbr, Guam, Marianas |
| Country | U.S.A. |
| Time zone | 150E, GMT + 10hrs |
| Latitude (+ve N) | 13.43333 |
| Longitude (+ve E) | 144.65 |
| Ocean | Pacific |
| Observation period(s) | 1948- |
| Responsible country | U.S.A. |
| Authority responsible for tide gauge | NOAA, National Ocean Service, 1305 East-West Highway, Silver Spring, MD 20910-3281, USA |
| GLOSS contact | USA |
| Committed to GLOSS | Yes |
| Operational | Yes |
| Location map | |
| Instrumentation | |
| Float | Yes |
| Pressure | No |
| Bubbler | Yes |
| Acoustic | Yes |
| Radar | No |
| Data | |
| Digital data | Yes |
| Additional parameters | Air temperature, barometric pressure, wind sensors |
| Data acquisition rate | Digital gauge: 6 minute interval (after 1976) Analog gauge: hourly heights (before 1976) |
| Fast delivery data at UHSLC | |
| High frequency data at BODC | |
| High frequency data at UHSLC | |
| Data held at national organisation | Yes |
| Real-time data available | Yes |
| Real-time data transmitted to GLOSS Fast Centre | |
| Additional parameters (real-time) | Air temperature, barometric pressure, wind sensors |
| Benchmarks | |
| Tide gauge benchmarks | Benchmark 4 (1949) is the primary benchmark (PBM) stamped 'NO 4 1949' set in the northwest side of a 6ft by 12ft concrete manhole in the centre of the road. |
| Benchmark relationships | TGBM is 9.83ft above Tide Gauge Zero (Station Datum) NOAA Chart Datum (MLLW) is 1.24ft above Station Datum Mean Sea Level (1960-1978) is 2.65ft above Station Datum |
| Auxiliary benchmarks | 9 additional benchmarks are levelled to the TGBM and the Tide Station on a yearly basis. BM's L, 5, and USN BM1 subsided during earthquake - October 1993 site inspection was primarily for levelling due to recent earthquake. Other benchmarks include: BM 11, BM 4, BM 12, BM 13, BM 7 (P.I.E.), BM K, BM 6, BM 13 |
| Data at PSMSL | |
| Annual MSL (RLR) data | |
| Annual MSL (RLR) plot | |
| PSMSL code | 701/001 |
| Other relevant codes | UHSLC 053 |
| Additional information | |
| Last updated | 1993-12-05 |
Related BODC pages
| Sea level portal | World Ocean Circulation Experiment (WOCE) — Sea level | |
| UK Tide Gauge Network | Climate Variability and Predictability (CLIVAR) | |
| GLOSS project page |
Related external links
| Global Sea Level Observing System (GLOSS) | Permanent Service for Mean Sea Level (PSMSL) | |
| University of Hawai`i Sea Level Centre (UHSLC) | World Ocean Circulation Experiment (WOCE) |
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