[524] | 1 | NOTES FOR HC08D_P COMPLETED ON 24/06/2004 |
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| 2 | ____________________________________________________________________________________________ |
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| 3 | ____________________________________________________________________________________________ |
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| 4 | |
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| 5 | DATA FILE |
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| 6 | |
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| 7 | |
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| 8 | |
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| 9 | Byte Location , Byte Size , Explanation |
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| 10 | -------------------------------------------------------------------------------------------- |
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| 11 | |
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| 12 | |
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| 13 | 1-2 ,2 , Record identifier - hd |
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| 14 | 4-9 ,6 , Bureau of Meteorology Station Number. |
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| 15 | 11-26 ,16 , (Local time)Day/Month/Year in DD/MM/YYYY format,Hour24:Minutes in HH24:MI format in Local time |
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| 16 | 28 ,1 , Message type |
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| 17 | 30-34 ,5 , *Air Temperature in Celsius |
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| 18 | 36-38 ,3 , Wind speed in km/h |
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| 19 | 40-42 ,3 , Wind direction in degrees |
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| 20 | 44-49 ,6 , *QNH preasure in hPa |
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| 21 | 51 ,1 , # symbol, end of record indicator. |
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| 22 | |
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| 23 | |
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| 24 | |
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| 25 | |
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| 26 | NOTE:- Any fields prefixed with '*' are derived from the 3 hourly table, and a different |
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| 27 | set of quality flags apply. |
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| 28 | |
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| 29 | |
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| 30 | |
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| 31 | |
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| 32 | Message type |
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| 33 | _________________________________________________________ |
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| 34 | |
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| 35 | m: METAR (routine aerodrome weather report), automatic |
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| 36 | M: METAR (routine aerodrome weather report), manual |
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| 37 | s: SPECI (special aerodrome weather report -where weather below certain criteria |
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| 38 | or there has been a significant change since last report), automatic |
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| 39 | S: SPECI (special aerodrome weather report - where weather below certain criteria |
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| 40 | or there has been a significant change since last report), manual |
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| 41 | |
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| 42 | |
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| 43 | |
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| 44 | |
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| 45 | Wind |
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| 46 | ________________________ |
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| 47 | |
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| 48 | Wind speed and direction are mostly an average over the 10 |
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| 49 | minutes prior to observation time. Where there is an observer |
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| 50 | recent (AWS= 0) and a marked discontinuity occurs then |
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| 51 | only data after the discontinuity is used and therefore the |
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| 52 | time period is less. In this case a marked discontinuity is |
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| 53 | a "sustained change in wind direction of 30° or more, with a |
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| 54 | wind speed of 10 knots or more before or after the change. |
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| 55 | or a change in wind speed of 10 knots or more, lasting at least |
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| 56 | two minutes". |
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| 57 | |
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| 58 | |
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| 59 | |
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| 60 | |
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| 61 | GAPS AND MISSING DATA |
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| 62 | _____________________ |
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| 63 | |
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| 64 | Very few sites have a complete unbroken record of climate information. A site |
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| 65 | may have been closed, reopened, upgraded to a full weather site or downgraded |
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| 66 | to a rainfall only site during its existence causing breaks in the record for |
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| 67 | some or all elements. Some gaps may be for one element due to a damaged |
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| 68 | instrument, others may be for all elements due to the absence or illness of |
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| 69 | an observer. |
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| 70 | |
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| 71 | |
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| 72 | |
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| 73 | |
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| 74 | INSTUMENTS AND OBSERVATIONAL PRACTICES |
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| 75 | ______________________________________ |
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| 76 | |
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| 77 | Historically a nearby site (within about 1 mile in earlier days) may have used the same |
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| 78 | site number. There may have been changes in instrumentation and/or observing practices |
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| 79 | over the period included in a dataset, which may have an effect on the long-term record. |
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| 80 | In recent years many sites have had observers replaced by Automatic Weather Stations, |
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| 81 | either completely or at certain times of the day. |
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| 82 | |
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| 83 | |
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| 84 | |
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| 85 | |
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| 86 | TIME |
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| 87 | ____ |
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| 88 | |
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| 89 | For a part of the year some Australian States adopt Daylight Savings Time (DST), and |
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| 90 | observers continue to take observations according to the local clock. Times provided |
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| 91 | with this data are Local Time, unless otherwise noted. |
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| 92 | |
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| 93 | Care needs to be taken when comparing values from year to year or month to month, because for |
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| 94 | some elements the effect of one hour can be marked, for example air temperature often rises |
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| 95 | sharply between 8am and 9am. |
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| 96 | |
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| 97 | Daylight Savings has been used in many Australian states since 1973. The |
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| 98 | changeovers occur almost always in October and March, but exact dates vary |
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| 99 | from State to State and year to year. More information can be found at: |
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| 100 | http://www.bom.gov.au/climate/averages/tables/daysavtm.shtml |
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| 101 | |
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| 102 | |
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| 103 | |
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| 104 | |
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| 105 | ROUNDING |
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| 106 | ________ |
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| 107 | |
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| 108 | The primary way of sending current weather information around the world is via a coded message |
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| 109 | known as a SYNOP. This message only allows some measurements to be sent as rounded values. |
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| 110 | Once manuscript records have been sent in many of these values are typed in with greater |
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| 111 | precision (normally to one decimal place). This usually occurs within a few months. |
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| 112 | |
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| 113 | If consecutive values all have a zero in the decimal place, then it is almost certain that |
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| 114 | rounding was used earlier. A new type of message format is progressively being introduced to |
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| 115 | overcome this situation. |
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| 116 | |
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| 117 | |
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| 118 | |
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| 119 | |
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| 120 | COPYRIGHT |
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| 121 | _________ |
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| 122 | |
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| 123 | The copyright for any data is held in the Commonwealth of Australia and the purchaser |
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| 124 | shall give acknowledgement of the source in reference to the data. Apart from dealings |
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| 125 | under the copyright Act, 1968, the purchaser shall not reproduce, modify or supply (by |
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| 126 | sale or otherwise) these data without written permission. Enquiries should be made in |
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| 127 | the first instance to the National Climate Centre, Bureau of Meteorology, |
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| 128 | PO Box 1289K, Melbourne 3001, marked to the attention of SRDS. |
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| 129 | |
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| 130 | |
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| 131 | |
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| 132 | |
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| 133 | LIABILITY |
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| 134 | _________ |
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| 135 | |
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| 136 | While every effort is made to supply the best data available this may not be possible |
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| 137 | in all cases. We do not give any warranty, nor accept any liability in relation |
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| 138 | to the information given, except that liability (if any), that is required by law. |
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| 139 | |
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| 140 | |
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| 141 | |
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| 142 | |
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| 143 | |
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| 144 | IF DATA IS NOT AS REQUESTED |
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| 145 | ___________________________ |
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| 146 | |
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| 147 | If the data provided are not as requested, the data will be repeated at no extra cost, |
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| 148 | provided that: |
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| 149 | a) the Bureau is notified within 60 days. |
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| 150 | b) the printout/disc/data file is returned to the Bureau for checking. |
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| 151 | c) there has been a fault or error in providing the data. |
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| 152 | |
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| 153 | Where there has been no fault or error of provision, the cost involved in |
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| 154 | requested corrective action such as resending the data or providing alternative |
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| 155 | sites will be charged for as necessary. |
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| 156 | |
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| 157 | |
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| 158 | |
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| 159 | |
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| 160 | ____________________________________________________________________________________________ |
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| 161 | ____________________________________________________________________________________________ |
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| 162 | |
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| 163 | SITE DETAILS FILE |
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| 164 | |
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| 165 | This file contains the details for the current site or are those which applied when the site |
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| 166 | was closed. Many sites have been moved, downgraded, upgraded etc over the years. |
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| 167 | |
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| 168 | Byte Location , Byte Size , Explanation |
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| 169 | -------------------------------------------------------------------------------------------- |
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| 170 | |
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| 171 | |
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| 172 | 1-2 ,2 , Record identifier - st |
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| 173 | 4-9 ,6 , Bureau of Meteorology Station Number. |
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| 174 | 11-14 ,4 , Rainfall district code |
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| 175 | 16-55 ,40 , Station Name. |
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| 176 | 57-63 ,7 , Month/Year site opened. (MM/YYYY) |
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| 177 | 65-71 ,7 , Month/Year site closed. (MM/YYYY) |
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| 178 | 73-80 ,8 , Latitude to 4 decimal places, in decimal degrees. |
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| 179 | 82-90 ,9 , Longitude to 4 decimal places, in decimal degrees. |
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| 180 | 92-106 ,15 , Method by which latitude/longitude was derived. |
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| 181 | 108-110 ,3 , State. |
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| 182 | 112-117 ,6 , Height of station above mean sea level in metres. |
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| 183 | 119-124 ,6 , Height of barometer above mean sea level in metres. |
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| 184 | 126-130 ,5 , WMO (World Meteorological Organisation) Index Number. |
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| 185 | 132-135 ,4 , First year of data supplied in data file. |
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| 186 | 137-140 ,4 , Last year of data supplied in data file. |
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| 187 | 142-144 ,3 , Percentage complete between first and last records. |
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| 188 | 146-148 ,3 , Percentage of values with quality flag 'Y'. |
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| 189 | 150-152 ,3 , Percentage of values with quality flag 'N'. |
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| 190 | 154-156 ,3 , Percentage of values with quality flag 'W'. |
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| 191 | 158-160 ,3 , Percentage of values with quality flag 'S'. |
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| 192 | 162-164 ,3 , Percentage of values with quality flag 'I'. |
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| 193 | 166 ,1 , # symbol, end of record indicator. |
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| 194 | |
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| 195 | |
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| 196 | |
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| 197 | |
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| 198 | LATITUDES AND LONGITUDES |
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| 199 | ________________________ |
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| 200 | |
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| 201 | Latitudes and longitudes are given to 4 decimal places, but in many cases will not be |
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| 202 | accurate to 4 decimal places. This is because in the early days the positions of stations |
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| 203 | were estimated from maps. Gradually the network of open stations is being checked (and |
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| 204 | if necessary corrected) using GPS (Global Positioning System). The method used is given |
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| 205 | in the site details file. |
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| 206 | |
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| 207 | |
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| 208 | |
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| 209 | |
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| 210 | WMO INDEX NUMBER |
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| 211 | ________________ |
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| 212 | |
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| 213 | This is the number assigned to a site that makes international weather reports every day. |
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| 214 | The number is not actively used in the climate archive, and only a few hundred such |
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| 215 | numbers are assigned at any time. These are not perpetual but may be reassigned |
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| 216 | where a site no longer makes the international reports (synops); thus a particular |
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| 217 | number cannot be regarded as unique and exclusive to any particular site. |
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| 218 | |
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| 219 | |
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| 220 | |
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| 221 | |
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| 222 | PERCENTAGE INFORMATION |
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| 223 | ______________________ |
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| 224 | |
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| 225 | In some cases the percentage completeness will be overestimated. This will occur if the |
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| 226 | database has incomplete information about the element being selected. In cases where several |
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| 227 | elements are selected, rows with a least one of the elements available are considered |
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| 228 | complete. Where only a limited amount of data is available and the percentage completeness |
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| 229 | is less than 0.5%, an "*" has been used. |
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| 230 | |
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| 231 | An "*" is also used if the percentage of values with a particular quality flag is non zero |
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| 232 | and less than 0.5%. |
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| 233 | |
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