Mera (Japan) Site History

History Summary

Station nameMera
CountryJapan
Latitude34° 55.0' N
Longitude139° 50.0' E
GLOSS No.086
Contributor1965-1986 TOGA Sea Level Center
1987-2009 Japan Meteorological Agency
Instrument TypeFUESS (1965-1972)
LFT-4 (1973-1999)
Fuess float operated gauge (2001-2005)
Acoustic gauge (2006-2009)
Site of Gauge 
Observational Periods1965 - present

Benchmarks

Reference Level

All heights have been referred to the station Tide Gauge Zero (TGZ) which is linked to fixed bench marks.

Tide Gauge Benchmark (TGBM) Description

Japan Meteorlogical Agency Benchmark bolt inside tide gauge hut, adjacent to stilling well

Auxiliary Benchmarks

Tide station Benchmark 4.3031m above Tokyo Peil (1984).

Benchmark Relationships

YearStandard Mark (TGBM)
above Datum Line (TGZ)
Standard Mark (TGBM)
above Tokyo Peil (TP)
TGZ below TP
1968-20006.6715.401-1.270
20016.6715.323-1.348
20026.6715.352-1.319
2003-20086.6715.297-1.374
20096.6715.287-1.384

Parameter Code

ASLVZZ01 - The elevation of the sea surface to a known datum, measured in metres.

Quality Assessment

The daily or monthly means do not reveal any obvious reference level shifts. Prior to 2001 most questionable fluctuations are related to timing problems with the gauge. Data spikes of about 10cm or less have not been corrected. In some years gaps in data have been replaced, details can be found in Replaced gaps table below.

Completeness index (CI)

Sea level data from Japan is processed for each year. Occasionally data is missing from the data sets, either because the data set does not cover the whole year or because data has been flagged null. The number of cycles in a year with no missing data is calculated (based on the sample interval and whether a leap year). The completeness index calculates what proportion of the data expected in a year is present and not flagged null.

Quality index (QI)

During processing cycles considered suspect within a series are flagged M. The quality index calculates what proportion of the data available is not considered suspect.

Yearly overview of data

YearCI (%)QI (%)Start and end date (UTC)Sampling interval
(minutes)
Missing Data
(cycle no.)
Suspect Data
(cycle no.)
Parameter Code
196599.997.41965-01-01 00:00 to 1965-12-31 14:0060None1120, 1127, 1302, 2224, 3649, 4080, 4263, 4780, 5182, 6222-6435, 7588, 8190ASLVZZ01
19670.1100.01967-12-31 15:00 to 1967-12-31 23:0060NoneNoneASLVZZ01
196899.199.71968-01-01 00:00 to 1968-12-31 23:00603090-3145, 3487-3511465, 533, 607, 609, 783, 821, 873-874, 951, 1897, 2542, 2712-2713, 3240, 3630, 4090, 4198, 4294, 4352, 5576, 5672, 7207, 8403, 8620ASLVZZ01
1969100.099.81969-01-01 00:00 to 1969-12-31 23:0060None2898, 3856, 8418, 8455, 8485, 8505-8506, 8594, 8701, 8754ASLVZZ01
1970100.099.81970-01-01 00:00 to 1970-12-31 23:0060None1475, 3602, 4352, 4454ASLVZZ01
1971100.099.81971-01-01 00:00 to 1971-12-31 23:0060None254, 897, 1473, 2673, 6178, 6187, 6586, 6958, 7476, 7479, 7606, 7683, 7767, 8206, 8394ASLVZZ01
1972100.099.81972-01-01 00:00 to 1972-12-31 23:0060None380, 846, 1591, 1670, 1852-1853, 1859, 1867, 1888, 3011, 3044, 3970, 4745, 4783, 6932, 7126, 7623, 7897, 8000, 8136, 8383ASLVZZ01
1973100.099.61973-01-01 00:00 to 1973-12-31 23:0060None87, 110, 161, 180, 461, 512, 549, 1249, 1809, 1850, 2368, 2462, 2522, 3198, 3359, 3441, 3508, 3621, 4194, 4426, 4489, 4514-4516, 4556, 4645, 4915, 6202, 7068, 7263, 7438, 7650, 7664, 7985, 8458, 8530 8623, 8634ASLVZZ01
1974100.098.71974-01-01 00:00 to 1974-12-31 23:0060None709, 973, 1370, 1376, 1446, 1479, 1521, 2382, 2769-2770, 2893, 2980, 3044, 3354, 3453, 3855, 3958, 4062, 5975, 6177-6268ASLVZZ01
197557.599.61975-01-01 00:00 to 1975-12-31 23:00601248-1299, 1408-5079623, 1048, 8677ASLVZZ01
1976100.099.81976-01-01 00:00 to 1976-12-31 23:0060None998, 4563, 4964ASLVZZ01
1977100.099.81977-01-01 00:00 to 1977-12-31 23:0060None2978ASLVZZ01
1978100.099.81978-01-01 00:00 to 1978-12-31 23:0060None2552, 4410ASLVZZ01
1979100.099.81979-01-01 00:00 to 1979-12-31 23:0060None3891ASLVZZ01
198099.699.81980-01-01 00:00 to 1980-12-31 23:0060788-8191184, 3249, 5714, 6876ASLVZZ01
1981100.099.81981-01-01 00:00 to 1981-12-31 23:0060None1543ASLVZZ01
1982100.099.81982-01-01 00:00 to 1982-12-31 23:0060None6081ASLVZZ01
1983100.0100.01983-01-01 00:00 to 1983-12-31 23:0060NoneNoneASLVZZ01
1984100.0100.01984-01-01 00:00 to 1984-12-31 23:0060NoneNoneASLVZZ01
1985100.0100.01985-01-01 00:00 to 1985-12-31 23:0060NoneNoneASLVZZ01
198699.9100.01986-01-01 00:00 to 1986-12-31 14:0060NoneNoneASLVZZ01
198798.2100.01986-12-31 15:00 to 1987-12-31 14:00602427-2508, 3923-3997, 7885-7889NoneASLVZZ01
198899.9100.01987-12-31 15:00 to 1988-12-31 14:00601969-1981NoneASLVZZ01
198999.999.91988-12-31 15:00 to 1989-12-31 14:00603315-33216294ASLVZZ01
1990100.0100.01989-12-31 15:00 to 1990-12-31 14:0060NoneNoneASLVZZ01
1991100.0100.01990-12-31 15:00 to 1991-12-31 14:0060NoneNoneASLVZZ01
1992100.0100.01991-12-31 15:00 to 1992-12-31 14:0060NoneNoneASLVZZ01
199399.9100.01992-12-31 15:00 to 1993-12-31 14:00607636-7642, 7736-7739NoneASLVZZ01
199499.9100.01993-12-31 15:00 to 1994-12-31 14:00602583-2586NoneASLVZZ01
1995100.0100.01994-12-31 15:00 to 1995-12-31 14:0060NoneNoneASLVZZ01
1996100.099.61995-12-31 15:00 to 1996-12-31 14:0060None365-366, 6366-6396ASLVZZ01
1997100.099.61996-12-31 15:00 to 1997-12-31 14:0060None4090-4110, 4289-4306ASLVZZ01
1998100.099.81998-01-01 00:00 to 1998-12-31 23:0060None6184-6198ASLVZZ01
1999100.0100.01999-01-01 00:00 to 1999-12-31 23:0060None6184-6198ASLVZZ01
2001100.0100.02000-12-31 15:00 to 2001-12-31 14:0060NoneNoneASLVZZ01
2002100.099.72001-12-31 15:00 to 2002-12-31 14:0060None4582-4590, 6567-6583ASLVZZ01
200399.8100.02002-12-31 15:00 to 2003-12-31 14:00602013-2026NoneASLVZZ01
2004100.0100.02003-12-31 15:00 to 2004-12-31 14:0060NoneNoneASLVZZ01
200599.9100.02004-12-31 15:00 to 2005-12-31 14:00601790-1793NoneASLVZZ01
2006100.0100.02005-12-31 15:00 to 2006-12-31 14:0060NoneNoneASLVZZ01
200799.9100.02006-12-31 15:00 to 2007-12-31 14:00607096-7097NoneASLVZZ01
2008100.0100.02007-12-31 15:00 to 2008-12-31 14:0060NoneNoneASLVZZ01
2009100.0100.02008-12-31 15:00 to 2009-12-31 14:0060NoneNoneASLVZZ01

Replaced gaps

YearReplaced Gaps (UTC)
19681968-05-23 06:00 to 1968-05-23 21:00,
1968-05-24 01:00 to 1968-05-25 00:00,
1968-05-26 12:00 to 1968-05-27 01:00 and
1968-05-27 23:00 to 1968-05-28 07:00
19741974-06-15 09:00 to 1974-06-15 17:00
19831983-01-07 07:00 to 1983-01-08 00:00 and
1983-01-08 03:00 to 1983-01-08 12:00
19861986-02-18 13:00 to 1986-02-19 04:00
19981998-09-14 10:00 to 1998-09-15 01:00