NOTES FOR IDCJHC01 COMPLETED ON 06/07/2010 ____________________________________________________________________________________________ ____________________________________________________________________________________________ DATA FILE Byte Location, Byte Size, Explanation -------------------------------------------------------------------------------------------- 1-2 , 2 , Record identifier - hc 4-9 , 6 , Bureau of Meteorology Station Number. 11-26 , 16 , Year month day hour minute in YYYY,MM,DD,HH24,MI format in Local Time. 28-43 , 16 , Year month day hour minute in YYYY,MM,DD,HH24,MI format in Local Standard Time. 45-49 , 5 , Wind speed measured in km/h. 51 , 1 , * Quality of wind speed. 53-57 , 5 , Wind direction measured in degrees. 59 , 1 , * Quality of wind direction. 61 , 1 , # symbol, end of record indicator. * QUALITY FLAG DESCRIPTIONS ___________________________ Y: quality controlled and acceptable N: not quality controlled W: quality controlled and considered wrong S: quality controlled and considered suspect I: quality controlled and inconsistent with other known information GAPS AND MISSING DATA _____________________ Very few sites have a complete unbroken record of climate information. A site may have been closed, reopened, upgraded to a full weather site or downgraded to a rainfall only site during its existence causing breaks in the record for some or all elements. Some gaps may be for one element due to a damaged instrument, others may be for all elements due to the absence or illness of an observer. INSTUMENTS AND OBSERVATIONAL PRACTICES ______________________________________ Historically a nearby site (within about 1 mile in earlier days) may have used the same site number. There may have been changes in instrumentation and/or observing practices over the period included in a dataset, which may have an effect on the long-term record. In recent years many sites have had observers replaced by Automatic Weather Stations, either completely or at certain times of the day. TIME ____ UTC - Coordinated Universal Time (sometimes called Greenwich Mean Time or GMT). Local Standard Time - The globe is divided into Standard time zones and Local Standard Time is the time specified for each zone. This is usually done in terms of hours ahead or behind UTC. Local Time - the time according to the local clock. Normally this is the same as Local Standard Time, but in periods of Daylight Saving an hour is added to the local clock, making Local Time an hour ahead of Local Standard Time. Care needs to be taken if analysing data against Local Time, as for part of the year many Australian states adopt Daylight Saving Time (DST), and observers continue to take observations according to the local clock. This means that a 9am observation taken in a period of Daylight Saving is really an 8am observation in Local Standard Time. For elements such as temperature the difference can be significant, as the temperature at this time of day is often rising quickly. Daylight Saving has been used in many Australian states since 1973, and on limited occasions prior to this. The changeovers generally occur in October and March, but exact dates vary from State to State and year to year. More information can be found at: http://www.bom.gov.au/climate/averages/tables/daysavtm.shtml ROUNDING ________ The primary way of sending current weather information around the world is via a coded message known as a SYNOP. This message only allows some measurements to be sent as rounded values. Once manuscript records have been sent in many of these values are typed in with greater precision (normally to one decimal place). This usually occurs within a few months. If consecutive values all have a zero in the decimal place, then it is almost certain that rounding was used earlier. A new type of message format is progressively being introduced to overcome this situation. COPYRIGHT _________ The copyright for any data is held in the Commonwealth of Australia and the purchaser shall give acknowledgement of the source in reference to the data. Apart from dealings under the copyright Act, 1968, the purchaser shall not reproduce, modify or supply (by sale or otherwise) these data without written permission. Enquiries should be made in the first instance to the National Climate Centre, Bureau of Meteorology, PO Box 1289K, Melbourne 3001, marked to the attention of SRDS. LIABILITY _________ While every effort is made to supply the best data available this may not be possible in all cases. We do not give any warranty, nor accept any liability in relation to the information given, except that liability (if any), that is required by law. IF DATA IS NOT AS REQUESTED ___________________________ If the data provided are not as requested, the data will be repeated at no extra cost, provided that: a) the Bureau is notified within 60 days. b) the printout/disc/data file is returned to the Bureau for checking. c) there has been a fault or error in providing the data. Where there has been no fault or error of provision, the cost involved in requested corrective action such as resending the data or providing alternative sites will be charged for as necessary. ____________________________________________________________________________________________ ____________________________________________________________________________________________ SITE DETAILS FILE This file contains the details for the current site or are those which applied when the site was closed. Many sites have been moved, downgraded, upgraded etc over the years. Byte Location, Byte Size, Explanation -------------------------------------------------------------------------------------------- 1-2, 2, Record identifier - st 4-9, 6, Bureau of Meteorology Station Number. 11-14, 4, Rainfall district code 16-55, 40, Station Name. 57-63, 7, Month/Year site opened. (MM/YYYY) 65-71, 7, Month/Year site closed. (MM/YYYY) 73-80, 8, Latitude to 4 decimal places, in decimal degrees. 82-90, 9, Longitude to 4 decimal places, in decimal degrees. 92-106, 15, Method by which latitude/longitude was derived. 108-110, 3, State. 112-117, 6, Height of station above mean sea level in metres. 119-124, 6, Height of barometer above mean sea level in metres. 126-130, 5, WMO (World Meteorological Organisation) Index Number. 132-135, 4, First year of data supplied in data file. 137-140, 4, Last year of data supplied in data file. 142-144, 3, ** Percentage complete between first and last records. 146-148, 3, Percentage of values with quality flag 'Y'. 150-152, 3, Percentage of values with quality flag 'N'. 154-156, 3, Percentage of values with quality flag 'W'. 158-160, 3, Percentage of values with quality flag 'S'. 162-164, 3, Percentage of values with quality flag 'I'. 166, 1, # symbol, end of record indicator. ** COMPLETENESS _______________ Unavailable for this product (IDCJHC01). LATITUDES AND LONGITUDES ________________________ Latitudes and longitudes are given to 4 decimal places, but in many cases will not be accurate to 4 decimal places. This is because in the early days the positions of stations were estimated from maps. Gradually the network of open stations is being checked (and if necessary corrected) using GPS (Global Positioning System). The method used is given in the site details file. WMO INDEX NUMBER ________________ This is the number assigned to a site that makes international weather reports every day. The number is not actively used in the climate archive, and only a few hundred such numbers are assigned at any time. These are not perpetual but may be reassigned where a site no longer makes the international reports (synops); thus a particular number cannot be regarded as unique and exclusive to any particular site. PERCENTAGE INFORMATION ______________________ No percentage completeness of data available for this product (IDCJHC01). Percentages only given for quality flags... An "*" is used if the percentage of values with a particular quality flag is non zero and less than 0.5%.