186SL0739113149101 351A 19650101 19921231 3904N 14143E 2 00000R 0000 MM 186SL0739213149101 Ofunato Japan Japan Meteorological Agency 186SL073930001 186SL073930002 QUALITY ASSESSMENT OF SEA LEVEL DATA 186SL073930003 by the 186SL073930004 TOGA SEA LEVEL CENTER/NATIONAL OCEANOGRAPHIC DATA CENTER 186SL073930005 JOINT ARCHIVE FOR SEA LEVEL 186SL073930006 186SL073930007Station : Ofunato Latitude: 39 04.0N 186SL073930008Country : Japan Longitude: 141 43.0E 186SL073930009JASL # : 351A Time Meridian: 135E (GMT + 9 hr) 186SL073930010GLOSS # : 087 TOGA #: none NODC #: 13149101 186SL073930011Contributor : Japan Meteorological Agency 186SL073930012 1-3-4 Otemachi, Chiyoda-ku 186SL073930013 Tokyo, Japan 186SL073930014Originator : Japan Meteorological Agency 186SL073930015Original Data: analog 186SL073930016Instrmnt Type: FUESS (1965-1972), LFT-4 (1973-1992) 186SL073930017Digitzd Intvl: hourly 186SL073930018Present Data : Hourly, daily, and monthly values obtained by: 186SL073930019 Hourly : hourly spot reading 186SL073930020 Daily : 119-point convolution filter (Bloomfield, 1976) 186SL073930021 centered on noon applied to the hourly data 186SL073930022 with respective periods of the 95, 50, and 5% 186SL073930023 amplitude points at 124.0, 60.2, and 40.2 hours 186SL073930024 Monthly: Simple average of all daily values; calculated if 186SL073930025 7 or fewer days are missing 186SL073930026Span of data : 01 Jan 1965 - 31 Dec 1992 186SL073930027Gaps > 1 mon : none 186SL073930028Time Refernce: GMT (hours 00-23) Space-filler Flag :-9999 186SL073930029Units : millimeters Missing Data Flag :99999 186SL073930030Refernce Levl: All data are referred to a historic fixed 186SL073930031 bench mark 186SL073930032Comment : The daily or monthly means do not reveal 186SL073930033 any obvious reference level shifts. Most 186SL073930034 questionable fluctuations are related to 186SL073930035 atmospheric or oceanographic events. Data 186SL073930036 spikes of about 10 cm or less have not been 186SL073930037 corrected. 186SL073930038 186SL073930039 CI MISSING REPLACED GAPS QUESTIONABLE 186SL073930040YEAR (%) DATA OR BAD DATA FLUCTUATIONS 186SL073930041---- --- -------------------- --------------- -------------------- 186SL0739300421965 96 112-114,115-117, 134(03)-135(01) 133-136,149-150, 186SL073930043 309-312,316-317, 318(06)-319(01) 152-153,260-261 186SL073930044 348-351 186SL0739300451966 100 none 279(06)-280(02) 240-241,285-286 186SL0739300461967 100 none none none 186SL0739300471968 99 103-107 004(09)-005(03) 15-18 186SL073930048 097(06)-098(04) 186SL0739300491969 98 215-220 289(19)-290(04) none 186SL0739300501970 100 none none none 186SL0739300511971 96 64-78 none none 186SL0739300521972 100 none none none 186SL0739300531973 100 none none none 186SL0739300541974 100 none none none 186SL0739300551975 100 none none none 186SL0739300561976 100 none none none 186SL0739300571977 100 none none none 186SL0739300581978 100 none none none 186SL0739300591979 100 none none none 186SL0739300601980 98 244-248 none none 186SL0739300611981 100 none none 234-235 186SL0739300621982 100 none 251(01)-251(07) none 186SL0739300631983 100 none none none 186SL0739300641984 100 none none none 186SL0739300651985 100 none none none 186SL0739300661986 100 none none none 186SL0739300671987 100 none none none 186SL0739300681988 100 none none none 186SL0739300691989 100 none none none 186SL0739300701990 100 none none none 186SL0739300711991 100 none none none 186SL0739300721992 99 366 none none 186SL073930073 186SL073930074 QUALITY ASSESSMENT POLICY 186SL073930075 186SL073930076 The quality assessment is mostly based on the residuals 186SL073930077 (observed data minus predicted tides) of the hourly data. This 186SL073930078 assessment also applies to the daily and monthly data since 186SL073930079 they were derived from the quality-controlled hourly data. 186SL073930080 186SL073930081 The following abbreviations are used in the assessment: 186SL073930082 JASL - Joint Archive for Sea Level; GLOSS - Global Sea Level 186SL073930083 Observing System; TOGA - Tropical Ocean Global Atmosphere 186SL073930084 research program; NODC - National Oceanographic Data Center; 186SL073930085 Instrmnt - instrument; Digitzd Intvl - digitized interval; 186SL073930086 Gaps > 1 mon - missing data in a span greater than one month; 186SL073930087 Refernce - reference. 186SL073930088 186SL073930089 The following corrections are made to the hourly data 186SL073930090 prior to this assessment: 186SL073930091 1) Gaps or obviously wrong data points in a span less than 186SL073930092 25 hours are filled by the predicted tide method*. 186SL073930093 2) Timing errors of exact increments of an hour are corrected 186SL073930094 by shifting the data. 186SL073930095 3) Reference level shifts are only corrected after information 186SL073930096 from tide staff readings or comparative readings with a fixed 186SL073930097 bench mark are checked to verify that the shift was not a 186SL073930098 natural event. If comparative readings are missing or 186SL073930099 incomplete, comparisons of the data with nearby stations 186SL073930100 may warrant the adjustment of some obvious shifts. 186SL073930101 4) Data with unresolved datum shifts are not disseminated. 186SL073930102 However, if sufficient time spans of data are available before 186SL073930103 or after the year(s) with the unresolved shift(s), a subset of 186SL073930104 quality assured data is made available. Thus, the Span field 186SL073930105 in the Quality Assessment may not match the span of the 186SL073930106 distribution data set. As the questionable datum shifts are 186SL073930107 resolved, the data set will be updated. Although this policy 186SL073930108 adds some complexity, it allows more rapid dissemination of 186SL073930109 at least the quality assured years. 186SL073930110 186SL073930111 For each year, the following information is documented from 186SL073930112 the quality-controlled hourly data with dates given as the nth 186SL073930113 day of the year starting from 1 January: 186SL073930114 1) a Completeness Index (CI) based on the percentage of hours 186SL073930115 with available data, 186SL073930116 2) a list of gaps longer than a day, 186SL073930117 3) a summary of days with consecutive missing or obviously 186SL073930118 wrong data in a time span longer than 6 but less than 25 186SL073930119 hours that have been replaced, with hours in parentheses, and 186SL073930120 4) a summary of days with questionable fluctuations in the 186SL073930121 residual series. Fluctuations within the residuals are 186SL073930122 considered significant and are noted if they are greater than 186SL073930123 25 cm. This policy has changed slightly as of October 1992: 186SL073930124 only suspicious fluctuations due to obvious instrumentation 186SL073930125 problems are noted. Minor timing drifts are no longer 186SL073930126 included in the list of questionable days. 186SL073930127 186SL073930128 Note : If the predicted tides poorly model the observed heights 186SL073930129 due to the inability of the tidal analysis to completely resolv 186SL073930130 the non-linear shallow water effects, the residuals are not 186SL073930131 suitable for assessing the data quality. Instead, a subjective 186SL073930132 comment on the quality of the data is provided. 186SL073930133 186SL073930134 *The predicted tides are obtained with the use of a harmonic 186SL073930135 analysis program (Foreman, 1977) which is executed on a year 186SL073930136 of apparently good data for a given station. The Predicted 186SL073930137 Tide Method for filling gaps consists of statistically 186SL073930138 comparing the predicted tides to the observed data and 186SL073930139 shifting the predicted tides in time to correct for timing 186SL073930140 differences. Then the linear interpolation between hourly 186SL073930141 values at the end points of the gap in the residual series is 186SL073930142 added to the corresponding corrected predicted tide data to 186SL073930143 obtain interpolated values over the span of the gap. 186SL073930144 186SL073930145 Bloomfield, P., 1976. Fourier Analysis of Time Series: An 186SL073930146 Introduction. New York: John Wiley and Sons. pp 129-137. 186SL073930147 186SL073930148 Foreman, M., 1977. Manual For Tidal Height Analysis and 186SL073930149 Prediction. Institute of Ocean Sciences, Patricia Bay, 186SL073930150 Victoria B.C. Pacific Marine Science Report 77-10. 186SL073930151 186SL07396 19651 1745000 1707000 1699000 1630060 1654000 1749000 186SL07396 19652 1829000 1855000 1881000 1805000 1793070 1774040 186SL07396 19661 1737000 1653000 1675000 1634000 1666000 1698000 186SL07396 19662 1776000 1877000 1886000 1836000 1784000 1775000 186SL07396 19671 1754000 1628000 1602000 1576000 1674000 1792000 186SL07396 19672 1845000 1906000 1902000 1843000 1744000 1744000 186SL07396 19681 1783000 1662000 1654000 1622050 1665000 1739000 186SL07396 19682 1835000 1920000 1878000 1860000 1835000 1850000 186SL07396 19691 1791000 1680000 1681000 1698000 1791000 1850000 186SL07396 19692 1859000 1958060 1930000 1893000 1880000 1863000 186SL07396 19701 1862000 1808000 1758000 1667000 1734000 1801000 186SL07396 19702 1866000 1888000 1923000 1912000 1897000 1847000 186SL07396 19711 1812000 173200099999999 1697000 1755000 1850000 186SL07396 19712 1935000 1942000 1964000 1928000 1813000 1820000 186SL07396 19721 1751000 1756000 1763000 1698000 1812000 1867000 186SL07396 19722 1941000 2013000 1998000 1984000 1947000 1880000 186SL07396 19731 1799000 1792000 1791000 1742000 1775000 1824000 186SL07396 19732 1862000 1934000 1955000 1900000 1922000 1911000 186SL07396 19741 1891000 1799000 1709000 1742000 1778000 1880000 186SL07396 19742 1906000 1965000 1935000 1951000 1867000 1841000 186SL07396 19751 1823000 1810000 1760000 1751000 1788000 1873000 186SL07396 19752 1901000 1952000 2010000 1914000 1861000 1877000 186SL07396 19761 1883000 1805000 1737000 1737000 1815000 1878000 186SL07396 19762 1890000 1955000 1967000 1970000 1869000 1884000 186SL07396 19771 1821000 1806000 1723000 1743000 1799000 1839000 186SL07396 19772 1916000 1977000 1986000 1872000 1853000 1897000 186SL07396 19781 1867000 1793000 1774000 1773000 1779000 1863000 186SL07396 19782 1919000 1988000 1973000 1955000 1885000 1835000 186SL07396 19791 1815000 1813000 1815000 1795000 1824000 1844000 186SL07396 19792 1967000 1995000 2023000 2023000 1966000 1901000 186SL07396 19801 1922000 1810000 1746000 1712000 1817000 1877000 186SL07396 19802 1908000 1941010 1952050 1948000 1933000 1999000 186SL07396 19811 1926000 1857000 1790000 1862000 1862000 1915000 186SL07396 19812 1941000 2040000 2028000 2075000 1975000 1933000 186SL07396 19821 1887000 1816000 1781000 1791000 1870000 1940000 186SL07396 19822 1945000 1990000 2011000 1999000 1937000 1891000 186SL07396 19831 1850000 1838000 1844000 1815000 1873000 1918000 186SL07396 19832 1992000 2001000 2034000 1971000 1962000 1960000 186SL07396 19841 1891000 1854000 1813000 1753000 1813000 1861000 186SL07396 19842 1940000 2013000 2018000 2010000 1920000 1879000 186SL07396 19851 1808000 1849000 1676000 1743000 1795000 1883000 186SL07396 19852 1987000 1984000 2000000 1979000 2027000 1938000 186SL07396 19861 1907000 1832000 1828000 1784000 1845000 1862000 186SL07396 19862 1928000 1998000 2039000 1957000 1924000 1914000 186SL07396 19871 1896000 1881000 1823000 1783000 1834000 1896000 186SL07396 19872 1987000 2029000 2001000 1978000 1937000 1873000 186SL07396 19881 1881000 1843000 1795000 1763000 1833000 1885000 186SL07396 19882 1934000 1957000 1969000 1971000 1947000 1887010 186SL07396 19891 1786000 1771000 1775000 1821000 1859000 1872000 186SL07396 19892 1876000 1993000 2017000 1955000 1926000 1973000 186SL07396 19901 1892000 1729000 1798000 1841000 1860000 1939000 186SL07396 19902 2005000 2063000 2034000 1966000 1969000 1930000 186SL07396 19911 1973000 1917000 1788000 1781000 1842000 1926000 186SL07396 19912 2010000 2090000 2015000 2035000 1973000 1915000 186SL07396 19921 1897000 1895000 1815000 1861000 1890000 1900000 186SL07396 19922 1967000 1973000 2044000 1998000 1936000 1925010