TITLE OF THE DATA SET Two Long-Term Instrumental Climatic Data Bases of the People's Republic of China DATA CONTRIBUTORS Tao Shiyan, Fu Congbin, Zeng Zhaomei, Zhang Qingyun Institute of Atmospheric Physics Chinese Academy of Sciences Beijing, China SOURCE AND SCOPE OF THE DATA Two PRC climate data bases, derived mainly from instrument measurements, are presented in this subdirectory (NDP039); one consists of monthly means, extremes, or totals of 14 meteorological variables observed at 60 stations, the other contains monthly mean temperatures and monthly precipitation totals from 205 stations. The two data bases have no stations in common. Each is described in detail in the following sections. 60-Station Network As previously noted, the data from these 60 stations consist of monthly means, extremes, or totals of the following 14 meteorological variables: Mean Station Pressure (mb) Mean Temperature (C) Mean Maximum Temperature (C) Mean Minimum Temperature (C) Total Precipitation (mm) Sunshine Duration (hours) Mean Cloud Amount (percentage of sky cover) Mean Relative Humidity (percent) Snow Days (days with snow cover) Dominant Wind Direction (degrees) Mean Wind Speed (m/s) Dominant Wind Frequency (percent) Extreme Maximum Temperature (C) Extreme Minimum Temperature (C) Each record contains one month's data; the WMO station number, year, and month, followed by the data variables in the same order as previously listed. Each data value is given in tenths of its specified unit of measure. Missing data values are indicated by "-9999". Four basic criteria were used in selecting stations to make up the 60-station network: (1) the station should be representative of a particular climate region of China, (2) the station's data should be of relatively high quality, (3) the period of record of the station should be reasonably long, and (4) the resulting station network should have a relatively uniform spatial distribution. Thirteen stations began observing before 1900, Beijing's record is the longest, with temperature and precipitation data dating back to 1841. All 60 stations have temperature and/or precipitation data available from the beginning of their periods of record, with other types of observations beginning more randomly with time throughout the network. Records from all stations run through 1988, but extreme maximum and minimum temperature data are available for each station only since 1984. Nearly one-half of the 60 stations have some type of data for at least 70 years, but only six have data for 100 years or more. Data are available from all 60 stations over the period 1951-1988. Periods of whole years without data are omitted from the data set. Station histories are available for these stations and are contained in Appendix B of the document which accompanies these files. 205-Station Network Data from the 205-station network contain two variables: monthly mean temperature and total monthly precipitation. The data are stored in two files, one with temperatures (in tenths of degrees Celsius) and the other with precipitation totals (in tenths of millimeters). Each record of a file contains data from one year: the WMO station number and year followed by twelve monthly data values. Missing values are represented by "-9999". The temperature data date back to 1907 (Jingzhou, No. 57476) and the precipitation data to 1880 (Wuhu, No. 58334). Temperature and precipitation records from 202 stations extend through 1988. Records from Geershiquanhe (No. 55228), Hekou (No. 56989), and Lingling (No. 57866) extend through 1982, 1980, and 1983, respectively. Because of their relatively small number, years without data have been left in these data sets. For both temperature and precipitation data, the most typical length of record ranges between 30-40 years, with a relatively small share of stations [29 stations (~15%) for temperature; 24 stations (~12%) for precipitation] having records for 50 or more years. The 60-station data set offers more truly long-term records and, as previously noted, contains temperature and/or precipitation data from the beginning of each station record. The first year for which all 205 stations have temperature and precipitation data is 1961. Unfortunately, station histories are not currently available for any of the stations in the 205-station network; therefore, details regarding instrumentation, collection methods, changes in station location or observing times, and official data sources are not known. DATA FORMAT The information within this subdirectory (NDP039) is arranged in sixteen files, containing the following: this descriptive file (NDP039.DES) five FORTRAN IV input/output routines (one per file) (NDP039.F2, ..., NDP039.F6) five SAS* input/output routines (one per file) (NDP039.F7, ..., NDP039.F11) the station inventory for the PRC 60-station network (NDP039.F12) the station inventory for the PRC 205-station network (NDP039.F13) the 60-station network climate data set (NDP039.F14) the 205-station network temperature data set (NDP039.F15) the 205-station network precipitation data set (NDP039.F16) STATION INVENTORY FILE FOR THE PRC 60-STATION NETWORK CLIMATE DATA SET The station inventory file for the 60-station climate data set (NDP039.F12) is sorted by 5-digit station number, with one record per station containing a sequence number (1-60), station name, station number, latitude, longitude, elevation above sea level, and the beginning year of the station's record. The file may be read using the following FORTRAN format: INTEGER SEQNUM,STANUM,LATDEG,LATMIN,LONDEG,LONMIN, + BEGYR REAL ELEV CHARACTER*10 STNAME READ(5,100,END=99)SEQNUM,STNAME,STANUM,LATDEG,LATMIN, + LONDEG,LONMIN,ELEV,BEGYR 100 FORMAT(1X,I2,1X,A10,2X,I5,3X,I2,1X,I2,3X,I3,1X,I2,2X,F6.1,2X,I4) or by using the SAS format: INPUT SEQNUM 2-3 STNAME $ 5-14 STANUM 17-21 LATDEG 25-26 LATMIN 28-29 LONDEG 33-35 LONMIN 37-38 ELEV 41-46 BEGYR 49-52 Stated in tabular form the contents include the following. Variable Variable Starting Ending Variable type width column column SEQNUM Numeric 2 2 3 STNAME Character 10 5 14 STANUM Numeric 5 17 21 LATDEG Numeric 2 25 26 LATMIN Numeric 2 28 29 LONDEG Numeric 3 33 35 LONMIN Numeric 2 37 38 ELEV Numeric 6 41 46 BEGYR Numeric 4 49 52 where SEQNUM is the station's relative position in the file (1-60); STNAME is the name of the station; STANUM is the WMO station number; LATDEG is the degrees portion of the station's latitude; LATMIN is the minutes portion of the station's latitude; LONDEG is the degrees (east) portion of the station's longitude; LONMIN is the minutes portion of the station's longitude; ELEV is the elevation of the station above sea level (m); and BEGYR is the beginning year of the station's record. STATION INVENTORY FILE FOR THE PRC 205-STATION NETWORK TEMPERATURE AND PRECIPITATION DATA SETS The station inventory file for the 205-station data sets (NDP039.F13) is sorted by 5-digit station number, with one record per station containing a sequence number (1-205), station name, station number, latitude, longitude, elevation above sea level, and the beginning years of the station's temperature and precipitation records. The file may be read using the following FORTRAN format: INTEGER SEQNUM,STANUM,LATDEG,LATMIN,LONDEG,LONMIN, + TBEGYR,PBEGYR REAL ELEV CHARACTER*20 STNAME READ(5,100,END=99)SEQNUM,STNAME,STANUM,LATDEG,LATMIN, + LONDEG,LONMIN,ELEV,TBEGYR,PBEGYR 100 FORMAT(1X,I3,1X,A20,1X,I5,2X,I2,1X,I2,2X,I3,1X,I2,2X,F6.1,2(2X,I4)) or by using the SAS format: INPUT SEQNUM 2-4 STNAME $ 6-25 STANUM 27-31 LATDEG 34-35 LATMIN 37-38 LONDEG 41-43 LONMIN 45-46 ELEV 49-54 TBEGYR 57-60 PBEGYR 63-66 Stated in tabular form, the contents include the following. Variable Variable Starting Ending Variable type width column column SEQNUM Numeric 3 2 4 STNAME Character 20 6 25 STANUM Numeric 5 27 31 LATDEG Numeric 2 34 35 LATMIN Numeric 2 37 38 LONDEG Numeric 3 41 43 LONMIN Numeric 2 45 46 ELEV Numeric 6 49 54 TBEGYR Numeric 4 57 60 PBEGYR Numeric 4 63 66 where SEQNUM is the station's relative position in the file (1-205); STNAME is the name of the station; STANUM is the WMO station number; LATDEG is the degrees portion of the station's latitude; LATMIN is the minutes portion of the station's latitude; LONDEG is the degrees (east) portion of the station's longitude; LONMIN is the minutes portion of the station's longitude; ELEV is the elevation of the station above sea level (m); TBEGYR is the beginning year of the station's temperature record; and PBEGYR is the beginning year of the station's precipitation record. 60-STATION NETWORK CLIMATE DATA FILE The climate data set from the 60-station network (NDP039.F14) contains monthly measurements of 14 climatological variables. The data are sorted by station number, with each record containing data for one month, including station number, year, month, mean station pressure, mean temperature, mean maximum and minimum temperatures, total precipitation, sunshine duration, mean cloud amount, mean relative humidity, total days with snow cover, dominant wind direction, mean wind speed, dominant wind frequency, and extreme maximum and minimum temperatures for the month (1984-1988 only). The file may be read using the following FORTRAN format: INTEGER STANUM,YEAR,MON,PRES,MEANT,MEANMX,MEANMN, + PRECIP,SUN,CLD,RH,SNOW,WDIR,WSPD,WFREQ,EXMX,EXMN CHARACTER*1 RECF,PRESF,MEANTF,MXF,MNF,PRECF,SUNF,CLDF, + RHF,SNOWF,WDIRF,WSPDF,WFREQF,EXMXF,EXMNF READ(5,100,END=99)STANUM,YEAR,MON,RECF,PRES,PRESF,MEANT, + MEANTF,MEANMX,MXF,MEANMN,MNF,PRECIP,PRECF,SUN,SUNF, + CLD,CLDF,RH,RHF,SNOW,SNOWF,WDIR,WDIRF,WSPD,WSPDF, + WFREQ,WFREQF,EXMX,EXMXF,EXMN,EXMNF 100 FORMAT(1X,I5,1X,I4,1X,I2,1X,A1,14(I6,1X,A1)) or by using the SAS format: INPUT STANUM 2-6 YEAR 8-11 MON 13-14 RECF $ 16 PRES 18-22 PRESF $ 24 MEANT 26-30 MEANTF $ 32 MEANMX 34-38 MXF $ 40 MEANMN 42-46 MNF $ 48 PRECIP 50-54 PRECF $ 56 SUN 58-62 SUNF $ 64 CLD 66-70 CLDF $ 72 RH 74-78 RHF $ 80 SNOW 82-86 SNOWF $ 88 WDIR 90-94 WDIRF $ 96 WSPD 98-102 WSPDF $104 WFREQ 106-110 WFREQF $ 112 EXMX 114-118 EXMXF $ 120 EXMN 122-126 EXMNF $ 128; Stated in tabular form, the contents include the following. Variable Variable Starting Ending Variable type width column column STANUM Numeric 5 2 6 YEAR Numeric 4 8 11 MON Numeric 2 13 14 RECF Character 1 16 16 PRES Numeric 5 18 22 PRESF Character 1 24 24 MEANT Numeric 5 26 30 MEANTF Character 1 32 32 MEANMX Numeric 5 34 38 MXF Character 1 40 40 MEANMN Numeric 5 42 46 MNF Character 1 48 48 PRECIP Numeric 5 50 54 PRECF Character 1 56 56 SUN Numeric 5 58 62 SUNF Character 1 64 64 CLD Numeric 5 66 70 CLDF Character 1 72 72 RH Numeric 5 74 78 RHF Character 1 80 80 SNOW Numeric 5 82 86 SNOWF Character 1 88 88 WDIR Numeric 5 90 94 WDIRF Character 1 96 96 WSPD Numeric 5 98 102 WSPDF Character 1 104 104 WFREQ Numeric 5 106 110 Variable Variable Starting Ending Variable type width column column WFREQF Character 1 112 112 EXMX Numeric 5 114 118 EXMXF Character 1 120 120 EXMN Numeric 5 122 126 EXMNF Character 1 128 128 where STANUM is the WMO station number; YEAR is the year of the data; MON is the month of the data; PRES is the monthly mean station pressure (mb); MEANT is the monthly mean temperature (C); MEANMX is the monthly mean of the daily maximum temperatures (C); MEANMN is the monthly mean of the daily minimum temperatures (C); PRECIP is the total precipitation (liquid and equivalent liquid of frozen precipitation) for the month (mm); SUN is the total sunshine duration for the month (hr); CLD is the mean cloud amount for the month (percent of sky cover); RH is the mean relative humidity for the month (percent); SNOW is the number of days in the month with measurable snow cover; WDIR is the dominant (most frequent) wind direction observed over the month, measured in 22.5 degree increments of azimuth clockwise from north (0 indicates calm winds, while 360 indicates a north wind); WSPD is the mean wind speed for the month (m/s); WFREQ is the dominant wind frequency for the month (percent); EXMX is the extreme maximum temperature observed for the month (C); and EXMN is the extreme minimum temperature observed for the month (C). All of the above meteorological variables are expressed in tenths of their specific units of measure. Flag codes for the data RECF is a flag denoting if any observations in the record have been corrected using other sources or flagged as being suspect. The following codes indicate which values have been flagged: P = pressure; T = one or more temperatures; R = precipitation total; S = sunshine duration; M = more than one type of parameter; and blank = record contains no data flags. PRESF is the pressure value flag. The codes are as follows: T = the pressure departs from general monthly trends; and E = pressure values for this year suggest a prior or subsequent change in barometer elevation not noted in the station history. MEANTF is a flag denoting suspect values of mean monthly temperature. The codes are as follows: A = outlier value*; not consistent with other reported mean temperature variables for this month; B = outlier value; repeated the following month; C = outlier value; D = value is identical to previous month's value; E = value does not fit typical monthly trends and is inconsistent with other reported mean temperature variables for the month; F = value is the highest ever reported for this month at this station and is repeated the following month; G = value is identical to previous month's value, which has been flagged as being suspect; and H = all three mean temperature variables have identical values over May and June of the current year. *Defined as lying 3.5 or more standard deviations away from the mean value of the variable. MXF is a flag denoting suspect values of monthly mean maximum tempeerature. The codes include A, D, E, and H from the aforementioned MEANTF flag, in addition to the following: I = outlier value; likely caused by an error in sign. MNF is a flag denoting suspect values of monthly mean minimum temperature. The codes are A, D, E, H, and I from the aforementioned MEANTF and MXF flags. PRECF is the precipitation total flag. The codes are as follow: R = total is identical to the previous or following month's total; H = total is especially high for this station and is considered suspect; and; E = original total was considered suspect due to being especially high for the station. It has been replaced by data from Eischeid et al. (1991). SUNF is the sunshine duration flag. The code used is: R = total is identical to the previous or following month's total. The data flags CLDF, RHF, SNOWF, WDIRF, WSPDF, WFREQF, EXMXF, and EXMNF are not used in the current version of the 60-station data set (their storage locations contain only blanks) because, of their associated variables, only the dominant wind direction data contain values of a questionable nature. Pre-1981 data contain a considerable number of dominant wind directions of 0 (calm winds), whereas data from the period 1984-1988 contain none. (Dominant wind direction data for the period 1981-1983 are missing.) 205-STATION MONTHLY MEAN TEMPERATURE FILE The temperature data set from the 205-station network (NDP039.F15) contains monthly mean temperatures. The data are sorted by station number, with each record containing data for one year, including station number, year, and mean temperatures for January through December. Temperatures are given in tenths of degrees Celsius. The file may be read using the following FORTRAN format: INTEGER STANUM, YEAR, TEMP(12) CHARACTER*1 RFLAG, TFLAG(12) READ (5,100,END=99) STANUM, YEAR, RFLAG, + (TEMP(I),TFLAG(I), I=1,12) 100 FORMAT(2I6,1X,A1,12(I6,1X,A1)) or by using the SAS format: INPUT STANUM 2-6 YEAR 9-12 RFLAG $ 14 JAN 16-20 JANFL $ 22 FEB 24-28 FEBFL $ 30 MAR 32-36 MARFL $ 38 Stated in tabular form, using variable names from the SAS format, the contents include the following. Variable Variable Starting Ending Variable type width column column STANUM Numeric 5 2 6 YEAR Numeric 4 9 12 RFLAG Character 1 14 14 JAN Numeric 5 16 20 JANFL Character 1 22 22 FEB Numeric 5 24 28 FEBFL Character 1 30 30 MAR Numeric 5 32 36 MARFL Character 1 38 38 APR Numeric 5 40 44 APRFL Character 1 46 46 MAY Numeric 5 48 52 MAYFL Character 1 54 54 JUN Numeric 5 56 60 JUNFL Character 1 62 62 JUL Numeric 5 64 68 JULFL Character 1 70 70 AUG Numeric 5 72 76 AUGFL Character 1 78 78 SEP Numeric 5 80 84 SEPFL Character 1 86 86 OCT Numeric 5 88 92 OCTFL Character 1 94 94 NOV Numeric 5 96 100 NOVFL Character 1 102 102 DEC Numeric 5 104 108 DECFL Character 1 110 110 where STANUM is the WMO station number; YEAR is the year of the data; and JAN-DEC are the monthly mean temperatures, given in tenths of degrees Celsius. Flag codes for the data RFLAG is a flag denoting whether any observations in the record are considered suspect and/or have been flagged. The codes are as follows: X = one or more temperatures have been flagged; Z = the record is not recommended for use due to a spurious series of at least three consecutive monthly values; and blank = the record contains no data flags. JANFL-DECFL are flags denoting suspect temperature values. The codes are as follows: A = outlier value*; departs from typical monthly trends; B = outlier value; likely caused by an error in sign; C = outlier value; repeated the following month; D = outlier value; identical to previous month's value; E = outlier value; F = value is identical to the previous month's value; G = this station (No. 54852) shows identical July and August temperatures over the period 1973-1975; H = this station (No. 57411) shows two pairs of repeated temperatures over the period May-August 1969. The values are not statistical outliers, but their pattern makes them suspect; and I = this station (No. 58734) has repeated temperatures for October-December 1945; the December value is an outlier. *Defined as lying 3.5 or more standard deviations away from the mean value of the variable. 205-STATION PRECIPITATION FILE The precipitation data set from the 205-station network (NDP039.F16) contains monthly precipitation totals. The data are sorted by station number, with each record containing data for one year, including station number, year, and precipitation totals for January-December (in tenths of millimeters). The file may be read using the following FORTRAN format: INTEGER STANUM,YEAR,P(12) CHARACTER*1 RFLAG, PFLAG(12) READ (5,100,END=99) STANUM, YEAR, RFLAG, (P(I),PFLAG(I), I=1,12) 100 FORMAT(2I6,1X,A1,12(I6,1X,A1)) or by using the SAS format: INPUT STANUM 2-6 YEAR 9-12 RFLAG $ 14 JAN 16-20 JANFL $ 22 FEB 24-28 FEBFL $ 30 MAR 32-36 MARFL $ 38 APR 40-44 APRFL $ 46 MAY 48-52 MAYFL $ 54 JUN 56-60 JUNFL $ 62 JUL 64-68 JULFL $ 70 AUG 72-76 AUGFL $ 78 SEP 80-84 SEPFL $ 86 OCT 88-92 OCTFL $ 94 NOV 96-100 NOVFL $ DEC 104-108 DECFL $ 110 Stated in tabular form, using variable names from the SAS format, the contents include the following. Variable Variable Starting Ending Variable type width column column STANUM Numeric 5 2 6 YEAR Numeric 4 9 12 RFLAG Character 1 14 14 JAN Numeric 5 16 20 JANFL Character 1 22 22 FEB Numeric 5 24 28 FEBFL Character 1 30 30 MAR Numeric 5 32 36 MARFL Character 1 38 38 APR Numeric 5 40 44 APRFL Character 1 46 46 MAY Numeric 5 48 52 MAYFL Character 1 54 54 JUN Numeric 5 56 60 JUNFL Character 1 62 62 JUL Numeric 5 64 68 JULFL Character 1 70 70 AUG Numeric 5 72 76 AUGFL Character 1 78 78 SEP Numeric 5 80 84 SEPFL Character 1 86 86 OCT Numeric 5 88 92 OCTFL Character 1 94 94 NOV Numeric 5 96 100 NOVFL Character 1 102 102 DEC Numeric 5 104 108 DECFL Character 1 110 110 where STANUM is the WMO station number; YEAR is the year of the data; and JAN-DEC are the monthly precipitation totals, given in tenths of millimeters. Flag codes for the data RFLAG is a flag denoting if any observations in the record have been flagged as being suspect. The codes are as follows: X = one or more precipitation totals have been flagged; and blank = the record contains no data flags. JANFL-DECFL are flags denoting suspect precipitation values. The single code used is: R = total is repeated over consecutive months*. *Totals less than or equal to 1.0 mm repeated over two or more consecutive months were not flagged. If all entries in records containing repeated totals contained zeros in their tenths place, the repeated totals were only flagged if they were greater than or equal to 10.0 mm. All non-zero totals repeated over three consecutive months were flagged regardless of magnitude. REFERENCES Eischeid, J. K., H. F. Diaz, R. S. Bradley, and P. D. Jones. 1991. A comprehensive precipitation data set for global land areas. DOE/ER-69017T-H1. Carbon Dioxide Research Division, U.S. Department of Energy, Washington, D.C.