of previous
version of NDP-048 documentation (data through 1990)(Current version of pdf file under construction.)
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Access all data files from NDP-048, with data through 2000
Access all data files from the previous version of NDP-048 (data through 1990, published in 1998)
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version of NDP-048 documentation (data through 1990)
(Current version of pdf file under construction.)
Date Published: November 2007
Prepared by the
Carbon Dioxide Information Analysis Center
OAK RIDGE NATIONAL LABORATORY
Oak Ridge, Tennessee 37831-6335
managed by
University of Tennessee-Battelle, LLC
for the
U.S. DEPARTMENT OF ENERGY
under contract DE-AC05-00OR22725
1. Name of the Numeric Data Package
2. Principal Investigators
3. Keywords
4. Background Information
5. Description of the Database
6. CDIAC Quality Assurance Checks
7. File Descriptions
1. Locations of stations in the 223-station former U.S.S.R. network
1. Inventory of stations in the 223-station former U.S.S.R. network
2. Gaps in the periods of record of the 223 former U.S.S.R. stations
Razuvaev, V. N., E. G. Apasova, and R. A. Martuganov. 2007. Six- and Three-hourly Meteorological
Observations from 223 Former U.S.S.R. Stations.
ORNL/CDIAC-108, NDP-048. Carbon Dioxide Information Analysis Center,
Oak Ridge National Laboratory, U.S. Department of Energy,
Oak Ridge, Tennessee.
This database contains 6- and 3-hourly meteorological observations from a 223-station network of the former Soviet Union. These data have been made available through cooperation between the two principal climate data centers of the United States and Russia: the National Climatic Data Center (NCDC), in Asheville, North Carolina, and the All-Russian Research Institute of Hydrometeorological Information-World Data Centre (RIHMI-WDC) in Obninsk, Russia. The first version of this database extended through the mid-1980s (ending year dependent upon station) and was made available in 1995 by the Carbon Dioxide Information Analysis Center (CDIAC) as NDP-048. A second version of the database extended the data records through 1990. This third, and current version of the database includes data through 2000 for over half of the stations (mainly for Russia), whereas the remainder of the stations have records extending through various years of the 1990s. Because of the break up of the Soviet Union in 1991, and since RIHMI-WDC is a Russian institution, only Russain stations are generally available through 2000. The non-Russian station records in this database typically extend through 1991. Station records consist of 6- and 3-hourly observations of some 24 meteorological variables including temperature, past and present weather type, precipitation amount, cloud amount and type, sea level pressure, relative humidity, and wind direction and speed. The 6-hourly observations extend from 1936 through 1965; the 3-hourly observations extend from 1966 through 2000 (or through the latest year available). These data have undergone extensive quality assurance checks by RIHMI-WDC, NCDC, and CDIAC. The database represents a wealth of meteorological information for a large and climatologically important portion of the earth's land area, and should prove extremely useful for a wide variety of regional climate change studies.
Six- and Three-hourly Meteorological Observations from 223 Former U.S.S.R. Stations
U.S.S.R., former Soviet Union, Russia, hourly data, air temperature, dew point temperature, relative humidity, water vapor pressure, sea level pressure, visibility, cloud amount, cloud height, wind direction, wind speed, precipitation amount, soil temperature, weather type, atmospheric phenomena
The Carbon Dioxide Information Analysis Center (CDIAC), through a cooperative agreement with NCDC , has packaged and made available to the public the four databases referred to above. The monthly mean temperature data from 243 stations (1891-1988) are included in the Global Historical Climatology Network database (Vose et al. 1992); the daily temperature and precipitation data from 223 stations (1881-1989) are documented in Razuvaev et al. (1993). The purpose of this numeric data package (NDP) is to update (for many stations, through 2000) the 6- and 3-hourly observations from the 223-station network of the former Soviet Union (FSU). These hourly data represent a wealth of meteorological information for a large and climatologically important part of the earth's land area and are described in the following sections.
The data records contained in this NDP include 25 types of meteorological observations from each of the 223 FSU stations. These observations appear in each record of the database in the order given below.
Not all stations have data for 1936-2000; some station records begin after 1936,
and some have gaps ranging from one month to several years.
An inventory of the 223-station network, including each station's name, World Meteorological
Organization (WMO) station number, latitude, longitude, elevation above sea level, and
beginning and ending years of record, is given in Table 1.
Stations with gaps in their period
of record are identified in Table 1 by asterisks, with these gaps presented in detail
in Table 2. A map
showing the locations of all 223 stations is presented in
Figure 1. The number plotted next to each
station in Figure 1 is the station sequence number given in the leftmost column
in Table 1.
Some basic data checks had been performed by RIHMI-WDC and NCDC prior to the arrival of the data at CDIAC. Extensive documentation pertaining to the units, acceptable ranges, and coding of variables in the database was provided by RIHMI-WDC to CDIAC. This information provided a basis for data checks performed by CDIAC and comprises the bulk of the database description presented in Sect. 7. Descriptions of data checks performed and a few general comments on findings are presented below.
Station numbers in data files were verified through comparison with station inventory information provided in a separate file by RIHMI-WDC and also through the WMO website (www.wmo.int).
Dates in data records were checked. Checks included:
This file is an ASCII version of this HTML documentation. It exists for the benefit of those downloading the database directly from CDIAC's anonymous FTP site without the use of a web browser.
These files are provided for the benefit of users with FORTRAN or SAS on their systems, enabling them to read any of the data files in this database using these software packages. The program files are:
Each record of the station inventory file contains a station's sequence number (1-223), WMO station number, name, latitude, longitude, elevation, beginning month and year of record, and ending month and year of record. The file may be read using invent.for or invent.sas. Stated in tabular form, the contents include
Variable Variable Starting Ending
Variable type width column column
SEQNUM Numeric 3 1 3
WMO Numeric 5 5 9
NAME Character 25 11 35
LAT Numeric 5 37 41
LON Numeric 7 43 49
ELEV Numeric 6 51 56
BMONTH Numeric 2 61 62
BYEAR Numeric 4 64 67
EMONTH Numeric 2 69 70
EYEAR Numeric 4 72 75
where
SEQNUM is the sequence number of the station in the data base (1-223);
WMO is the WMO No. of the station;
NAME is the name of the station;
LAT is the latitude of the station in decimal degrees north;
LON is the longitude of the station in decimal degrees east;
ELEV is the elevation of the station above sea level (meters) missing elevations
are coded as -999.9;
BMONTH is the beginning month of the station's period of record;
BYEAR is the beginning year of the station's period of record;
EMONTH is the ending month of the station's period of record; and
EYEAR is the ending year of the station's period of record.
DATA GAPS FILE (gaps.dat)This file contains information on stations that have at least one gap of at least one month in duration at any time during their period of record. There are only two variables in the file: WMO (WMO station number), a numeric variable in columns 1-5, and GAP (month/year with no data or the range of months/years with no data), a character variable in columns 9-25. Many stations have more than one record in this file, due to multiple gaps in their periods of record. This file may be read with gaps.for or gaps.sas.
STATION TIMEZONE FILE (timezone.dat)
This file contains information for converting observations at each former U.S.S.R. station from GMT (the time given in the data files) to LMT. There are only two variables in the file: WMO (WMO station number), a numeric variable in columns 1-5, and ZONE (the number of hours that must be added to the GMT of an observation to obtain the LMT of the observation), a numeric variable in columns 7-8 ranging from 3 to 13 h. This file may be read with timezone.for or timezone.sas.
Further data checks performed as part of updating the FSU database through 1990 (the previous version of the database) uncovered evidence of several stations requiring a new timezone assignment at some point in their period of record in order for the data to be properly sorted over time. The main check made use of the variable PTND, which is the reported change in station pressure from the previous observation to the current observation. Taking the difference of actual station pressure values from successive observations and comparing this difference to the value of PTND occasionally produced conflicting results. This always signaled a point in a station's record where the hourly values needed to be sorted differently from that point forward so as to be serially correct. It is uncertain whether these needed modifications resulted from actual changes in official timezone designation at stations or from changes in local observing time. This information is important for users who wish to calculate the correct LMT of observations. The required adjustment is to increase the value of the variable ZONE in (timezone.dat) by 1 hour for particular stations beyond specific dates. Stations that this applies to are given below by WMO station number with the required date of change.
24966 - October 1, 1981
25551 - January 1, 1982
27648 - January 1, 1970
27947 - April 1, 1981
34123 - April 1, 1981
34139 - April 1, 1981
In addition, further QA checks determined that the correct value of the ZONE variable for Kolpasev (WMO No. 29231) is 7, not 5 as given in Razuvaev et al. (1995). The file timezone.dat has been modified accordingly.
STATION HISTORY FILE (station.his)
This file contains information on rain gauge replacement dates and the date, direction, and distance of any station relocations. It only reflects information available as of the late 1980s. There are two types of entries for each station. One type contains the station's WMO No. and rain gauge replacement date. The other type contains the station's WMO No. and a relocation date, distance, and direction. The file is sorted by WMO No., year, month, and day. This file may be read using history.for or history.sas. Stated in tabular form, the contents include
Variable Variable Starting Ending
Variable type width column column
WMO Numeric 5 1 5
TYPE Character 4 7 10
YEAR Numeric 4 12 15
MONTH Numeric 2 17 18
DAY Numeric 2 20 21
DIST Character 2 23 24
DIRECT Character 3 26 28
where
WMO is the WMO No. of the station;
TYPE is the type of change indicated by this entry. The possible values of TYPE
are as follows:
RAIN = rain gauge replacement (i.e., change from old-type gauge
to Tretyakov-type gauge). Each station will have only one
RAIN entry. When this type of entry is used, DIST and
DIRECT (described below) are not relevant and thus are
coded as blanks;
MOVE = station relocation. Each station will have at least one
MOVE entry. If a station moved on more than one
occasion, then separate entries are included for each
relocation. If a station never moved, then that station will
have only one MOVE entry; in this entry, YEAR,
MONTH, DAY, DIST, and DIRECT (described below) are
all coded as missing. In other words, if a station has only
one MOVE entry, and if all variables in that MOVE entry
are coded as missing, then the given station never moved;
YEAR is the year in which the change took place. Missing years are coded as
999;
MONTH is the month in which the change took place. Missing months are coded
as 9;
DAY is the day on which the change took place. Missing days are coded as 9;
DIST is the distance (km) that the station was moved. Missing distances are
coded as 9. A distance of zero indicates that the station moved less than 1
km. DIST only applies to station relocation entries (i.e., lines in which
TYPE = MOVE). In rain gauge replacement entries (i.e., lines in which
TYPE = RAIN), DIST is not relevant and thus is coded as blanks; and
DIRECT is the direction in which the station was moved (e.g., N = north, SE =
southeast). Missing directions are coded as 99. DIRECT only applies to
station relocation entries (i.e., lines in which TYPE = MOVE). In rain
gauge replacement entries (i.e., lines in which TYPE = RAIN), DIRECT is
not relevant and thus is coded as blanks.
STATION DATA FILES (XXXXX.dat)These files (where "XXXXX" is filled with a particular station's 5-digit WMO station number) contain the 6- and 3-hourly meteorological observations from the stations. They may be read with data.for or data.sas. The date and time in all data records correspond with GMT. Stated in tabular form, the contents include the following numeric variables
Variable Starting Ending
Variable width column column
WMO 5 1 5
YEAR 4 6 9
MONTH 2 10 11
DAY 2 12 13
HOUR 2 14 15
RH 3 16 18
RHQF 1 19 19
VAPORP 3 20 22
VAPQF 1 23 23
SLP 5 24 28
SLPQF 1 29 29
HDEF 3 30 32
HDEFQF 1 33 33
PCHR 1 34 34
PCHRQF 1 35 35
PTND 3 36 38
PTNDQF 1 39 39
VIS 2 40 41
VISCF 1 42 42
VISQF 1 43 43
HCLD 2 44 45
HCLDCF 1 46 46
HCLDQF 1 47 47
TDEW 3 48 50
TDEWQF 1 51 51
GRND 1 52 52
GRNDQF 1 53 53
TCLD 2 54 55
TCLDCF 1 56 56
TCLDQF 1 57 57
LCLD 2 58 59
LCLDCF 1 60 60
LCLDQF 1 61 61
WDIR 2 62 63
WDIRQF 1 64 64
WSPD 2 65 66
WSPDQF 1 67 67
PRCP 4 68 71
PRCPCF 1 72 72
PRCPQF 1 73 73
STAP 5 74 78
STAPQF 1 79 79
SOILT 3 80 82
SOILQF 1 83 83
W 1 84 84
WCF 1 85 85
WQF 1 86 86
WW 2 87 88
WWQF 1 89 89
AIRT 4 90 93
AIRTQF 1 94 94
APH1 1 95 95
APH1CF 1 96 96
APH1QF 1 97 97
APH2 1 98 98
APH2CF 1 99 99
APH2QF 1 100 100
APH3 1 101 101
APH3CF 1 102 102
APH3QF 1 103 103
APH4 1 104 104
APH4CF 1 105 105
APH4QF 1 106 106
APH5 1 107 107
APH5CF 1 108 108
APH5QF 1 109 109
APH6 1 110 110
APH6CF 1 111 111
APH6QF 1 112 112
APH7 1 113 113
APH7CF 1 114 114
APH7QF 1 115 115
CLDH 1 116 116
CLDHCF 1 117 117
CLDHQF 1 118 118
CLDM 1 119 119
CLDMQF 1 120 120
CLDL1 1 121 121
CLDL1F 1 122 122
CLDL2 1 123 123
CLDL2F 1 124 124
CLDL3 1 125 125
CLDL3F 1 126 126
WIR 1 127 127
WIRF 1 128 128
where
WMO is the WMO number of the station;
YEAR is the year (Greenwich) of the observations in the record;
MONTH is the month (Greenwich) of the observations in the record;
DAY is the day (Greenwich) of the observations in the record;
HOUR is the GMT of the observations in the record;
RH is the relative humidity of the air (expressed in percent) as determined by
use of a psychrometer. Relative humidity is defined as the ratio of the
observed vapor pressure to the saturation vapor pressure for the observed
air temperature. Values of observations may range from 0 to 100%.
Missing observations are coded as 999;
RHQF is the quality flag for the relative humidity observation (0 indicates a valid
observation; 9 indicates a suspect or missing observation);
VAPORP is the water vapor pressure of the air [expressed in tenths of hectopascals
(hPa)] as determined by use of a psychrometer. The water vapor pressure
is the partial pressure of the water vapor contained in the air. Values of
observations considered valid may range from 0.0 to 95.0 hPa. Missing
observations are coded as 999;
VAPQF is the quality flag for the water vapor pressure observation (0 indicates a
valid observation; 9 indicates a suspect or missing observation);
SLP is the sea level pressure of the air (expressed in tenths of hPa) as
determined by use of a barometer. Because a station would rarely be able
to position a barometer precisely at sea level, the air pressure measured at
a station is "reduced" to sea level by using a standard barometric height
formula. Values of observations considered valid may range from 900.0 to
1100.0 hPa. At stations located above a certain elevation (500 m through
1980; 800 m since 1981), air pressure is not reduced to sea level, but is
assigned the missing code 99999;
SLPQF is the quality flag for the sea level pressure observation (0 indicates a valid
observation; 9 indicates a suspect or missing observation);
HDEF is the humidity deficit (saturation deficiency); the difference between the
saturation vapor pressure and the actual water vapor pressure at a given
temperature and pressure as measured in tenths of hPa. Valid values may
range from 0.0 to 95.0 hPa. Missing observations are coded as 999;
HDEFQF is the quality flag for the humidity deficit observation (0 indicates a valid
observation; 9 indicates a suspect or missing observation);
PCHR is the pressure tendency characteristic, corresponding to the shape of the
barograph trace of air pressure at the station for the preceding 3-h period.
This is a coded value ranging from 0 to 8, as explained below (a missing
value is coded as 9):
0 = increasing, then decreasing; pressure unchanged or higher than 3 h ago;
1 = increasing, then steady; increasing, then weaker increase;
current pressure is higher than 3 h ago;
2 = uniform or non-uniform increase; current pressure is higher than 3 h ago;
3 = decreasing, then increasing; steady, then increasing; or
increasing, then increasing more rapidly; current pressure is
higher than 3 h ago;;
4 = steady; pressure is the same as 3 h ago;
5 = decreasing, then increasing; pressure is the same or lower than 3 h ago;
6 = decreasing, then steady; or decreasing then decreasing more
slowly; current pressure is lower than 3 h ago;
7 = decreasing steadily or unsteadily; current pressure is lower than 3 h ago;
8 = increasing, then decreasing; steady, then decreasing; or
decreasing, then decreasing more quickly; current pressure is
lower than 3 h ago;
PCHRQF is the quality flag for the pressure tendency characteristic (0 indicates a
valid observation; 9 indicates a suspect or missing observation);
PTND is the pressure tendency value (i.e., the absolute difference between the
current air pressure at the station and that which was observed 3 h before).
The sign of PTND is indicated by the value of PCHR: if PCHR is equal to
0, 1, 2, or 3, then PTND is positive; if PCHR is equal to 4 then PTND
should equal 0; and, if PCHR is equal to 5, 6, 7, or 8, then PTND is
negative. Values are given in tenths of hPa; observations considered valid
may range from 0.0 to 20.0 hPa, and a missing observation is coded as
999);
PTNDQF is the quality flag for the pressure tendency value (0 indicates a valid
observation; 9 indicates a suspect or missing observation);
VIS is the horizontal visibility, given as a coded value indicating distance in
km. The horizontal visibility is defined as the maximum distance at which
an absolutely black body of rather large angular dimensions (over 15
angular min) can be distinguished against the background of the sky in
daylight, or the distance at which an unfocused light source of a given
intensity becomes indistinguishable at night. Horizontal visibility depends
on atmospheric phenomena. Thus, in the fog it can be reduced to zero,
while in clear arctic air it can reach hundreds of kilometers. Coded values
may range from 00 to 50 and from 56 to 99. Codes 00-50 and 56-89 are
used when visibility is measured using instruments; codes 90-99 are used
when visibility is estimated visually. The codes and their meanings are as
follows:
00-50 = indicates visibility in tenths of km (i.e., 0.0 km to 5.0 km).
For example, 25 = 2.5 km (00 is the code for visibility less
than 0.1 km);
51-55 = not used;
56-80 = the range 6 km to 30 km. Visibility in whole kilometers
may be determined by subtracting 50 from the code, e.g., a
code of 65 indicates the visibility is 15 km;
81 = 35 km;
82 = 40 km;
83 = 45 km;
84 = 50 km;
85 = 55 km;
86 = 60 km;
87 = 65 km;
88 = 70 km;
89 = >70 km;
90 = <0.05 km;
91 = 0.05 km;
92 = 0.2 km;
93 = 0.5 km;
94 = 1 km (about 1/2 mile);
95 = 2 km (about 1 mile);
96 = 4 km (about 2 miles);
97 = 10 km (about 6 miles);
98 = 20 km (about 12 miles); and
99 = >50 km (>30 miles).
If VIS = 99 with both the complement and quality flags set to 9 (see
below), the observation is missing.
VISCF is the horizontal visibility complement flag. VISCF = 0 indicates the
visibility corresponds to the value given for VIS; VISCF = 1 indicates the
visibility is actually greater than the value given for VIS; VISCF = 9
indicates a suspect or missing observation;
VISQF is the quality flag for the horizontal visibility value (0 indicates a valid
observation; 9 indicates a suspect or missing observation);
HCLD is the height above ground of the base of the lowest cloud. This height is
usually coded in hundreds of meters, as detailed in the following:
00 = less than or equal to 50 m with fog present;
01-25 = 100 m to 2500 m, e.g., 10 = 1000 m;
98 = no clouds below 2500 m, however there may be mid- or
high-level clouds whose height has not been determined;
99 = no clouds or traces of clouds whose height has not been
determined; or observation is missing if both complement
and quality flags are set to 9 (see below);
HCLDCF is the complement flag for the lowest cloud height observation. A value of
0 means the height was measured using instrumentation; a value of 1
indicates the height was estimated visually. This flag is set to 9 in the
case of a suspect or missing observation;
HCLDQF is the quality flag for the lowest cloud height observation (0 indicates a
valid observation; 9 indicates a suspect or missing observation);
TDEW is the dew point temperature in whole degrees celsius. The dew point
temperature is defined as the temperature to which moist air must be
cooled, with air pressure and water vapor pressure held constant, in order
that it just reach saturation with respect to the water in the air. The dew
point is determined by using a psychrometer. Observations considered
valid may range from -70° to +40°C. Missing observations are coded as 999;
TDEWQF is the quality flag for the dew point temperature (0 indicates a valid
observation; 9 indicates a suspect or missing observation);
GRND is the ground state, a visual observation of the state of the ground surface
in the vicinity of the station made usually near 0800 and 2000 LMT. This
is a coded value as detailed in the following:
0 = surface of ground dry (no appreciable amount of dust or loose sand);
1 = surface of ground moist (no pools);
2 = surface of ground wet (standing water in small or large pools on surface);
3 = surface of ground frozen;
4 = glaze on ground, but no snow or melting snow;
5 = ice, snow, or melting snow covering less than one-half of the ground;
6 = ice, snow, or melting snow covering more than one-half of the ground;
7 = ice, snow, or melting snow covering ground completely;
8 = loose dry snow, dust, or sand covering more than one-half of the ground;
9 = loose dry snow, dust, or sand covering ground completely (if GRNDQF = 0;
otherwise, the observation is missing);
GRNDQF is the quality flag for the ground state observation (0 indicates a valid
observation; 9 indicates a suspect or missing observation);
TCLD is the total cloud amount, estimated visually by an observer according to a
10-point system (i.e., in tenths of sky cover). A value of 0 indicates no
clouds present or <1/10 sky cover, a value of 10 indicates an overcast sky
(with or without gaps amounting to <1/10 sky cover; see explanation of
complement flag below), and a value of 99 indicates a missing
observation. The gaps between individual cloud elements, typical of some
cloud genera (e.g., altocumulus and stratocumulus) are not to be included
as part of the total cloud cover estimate (i.e., they are counted as clear sky);
TCLDCF is the total cloud amount complement flag. TCLDCF = 1 is used if
10-point cloudiness (overcast) is observed with gaps; TCLDCF = 0 is
coded for all other valid cloud amounts; and TCLDCF = 9 indicates a
suspect or missing observation;
TCLDQF is the quality flag for the total cloud amount observation (0 indicates a
valid observation; 9 indicates a suspect or missing observation);
LCLD is the low-cloud amount, estimated visually by an observer according to a
10-point system (i.e., in tenths of sky cover). A value of 0 indicates no
low clouds present or <1/10 of the sky is covered with low clouds. The
gaps between individual cloud elements, typical of some cloud genera
(e.g., stratocumulus and cumulus) are not to be included as part of the low
cloud cover estimate (i.e., they are counted as clear sky). Missing
observations are coded as 99;
LCLDCF is the low-cloud amount complement flag. TCLDCF = 1 is used if
10-point cloudiness (overcast) is observed with gaps; TCLDCF = 0 is
coded for all other valid low-cloud amounts; and TCLDCF = 9 indicates a
suspect or missing observation;
LCLDQF is the quality flag for the total cloud amount observation (0 indicates a
valid observation; 9 indicates a suspect or missing observation);
WDIR is the direction from which the wind is blowing, as measured 10-12 m
above ground level. This is a coded observation, the values for which are
given as follows:
Code Wind direction
---- --------------
00 = calm winds
02 = NNE
05 = NE
07 = ENE
09 = E
11 = ESE
14 = SE
16 = SSE
18 = S
20 = SSW
23 = SW
25 = WSW
27 = W
29 = WNW
32 = NW
34 = NNW
36 = N
99 = variable winds (if WDIRQF = 0; otherwise, the observation is missing);
WDIRQF is the quality flag for the wind direction observation (0 indicates a valid
observation; 9 indicates a suspect or missing observation). Missing
observations are coded as 99;
WSPD is the wind speed in m/s as measured 10-12 m above ground level.
Observations considered valid may range from 0 to 60 m/s;
WSPDQF is the quality flag for the wind speed observation (0 indicates a valid
observation; 9 indicates a suspect or missing observation);
PRCP is the precipitation amount to the nearest tenth of a millimeter.
Observations considered valid may range from 0 to 5000 (0 mm to 500 mm).
Missing observations are coded as 9999. Rain gauges are positioned
2 m above ground level, and were read at 0700 and 1900 LMT from 1936
through 1965. In 1946, the old-style gauge (exact type unknown) was
replaced with the Tretyakov-type gauge (see Appendix A for the date of
implementation at each site). Beginning in 1966, gauges were read at
0300, 0900, 1500, and 2100 MLT in timezone 2; at 0300, 0600, 1500,
and 1800 MLT in zones 3-5; at 0300 and 1500 MLT in zones 6-8; at
0000, 0300, 1200, and 1500 MLT in zones 9-11; and at 2100, 0300, 0900,
and 1500 MLT in zone 12. Also, beginning in 1966, wetting corrections
of 0.2 mm were applied to each hourly measurement. (Because four
observations per day were collected at stations in timezones 2-5 and
9-12, four corrections were counted in the calculation of daily totals;
therefore, total daily corrections are higher for stations in these areas.)
From 1966 onward, readings at some stations were also taken at the
observing hours closest to 0800 and 2000 LMT. Beginning in 1986,
readings at 0300 and 1500 MLT were discontinued at all stations except
those in timezone 2. (The term "timezone" in the preceding corresponds
to assigning the numbers 1-12 to 12 timezones stretching from west to
east across the FSU. The timezone of each station in this
sense may be obtained by subtracting 1 from the value of the ZONE
variable in the file timezone.dat.)
PRCPCF is the precipitation amount complement flag. It is set to 1 if a trace of
precipitation has been measured, i.e., <0.1 mm. This flag is set to 0 for all
other valid precipitation observations, and is set to 9 for suspect or missing
precipitation observations;
PRCPQF is the quality flag for the precipitation amount (0 indicates a valid
observation; 9 indicates a suspect or missing observation);
STAP is the pressure of the air at station level (expressed in tenths of hPa) as
determined by use of a barometer. Values of observations considered valid
may range from 600.0 to 1100.0 hPa. Validity is of course assessed by
considering factors such as the station's elevation above sea level,
geographic location, season, and pressures at neighboring stations.
Missing observations are coded as 99999;
STAPQF is the quality flag for the station level pressure observation (0 indicates a
valid observation; 9 indicates a suspect or missing observation);
SOILT is the soil surface temperature, expressed in whole degrees celsius. Soil
surface temperature is measured at a smooth, unshaded site that is devoid
of vegetation. When the ground is snow-covered, the thermometer is
placed on the snow surface and the temperature of the snow cover is
measured. Observations considered valid may range from -75 to +75°C.
Missing observations are coded as 999;
SOILQF is the quality flag for the soil surface temperature (0 indicates a valid
observation; 9 indicates a suspect or missing observation);
W is the past weather code, used in describing the meteorological conditions
observed between the past and current observations. At 0000, 0600, 1200,
and 1800 GMT this code describes weather from the previous 6-hour
period; at 0300, 0900, 1500, and 2100 GMT it describes weather for the
previous 3-hour period. The codes and their meanings are as follows:
0 = clear sky or no more than 5/10s cloud amount;
1 = variable sky; cloud amount was both less than and greater than
5/10 sky cover during the preceding three hours;
2 = overcast or cloud amount greater than 5/10s;
3 = sand or dust storm, or drifting or blowing snow;
4 = fog, ice fog, or thick haze or smoke;
5 = drizzle;
6 = rain;
7 = snow, or rain and snow mixed;
8 = shower(s);
9 = thunderstorm, with or without precipitation (if WQF = 0;
otherwise, the observation is missing);
WCF is the past weather complement flag. It is set to 0 when used with the
previously defined past weather codes, however it is set to 1 for past
weather codes 3, 7, and 8 if the past weather also included a snowstorm.
The complement flag is set to 9 in the case of a suspect or missing past
weather observation;
WQF is the quality flag for the past weather observation (0 indicates a valid
observation; 9 indicates a suspect or missing observation);
WW is the present weather code, reflecting the meteorological conditions at the
time of observation or during the preceding 1-h period. Codes range from
00 to 99 and are defined as follows:
Code Present weather
---- ---------------
00-19 = no precipitation, fog, dust storm, sandstorm, drifting or
blowing snow at the station at the time of observation
and, except for codes 09 and 17, during preceding hour;
00 = cloud development conditions unknown;
01 = cloud generally dispersing;
02 = state of sky on the whole unchanged;
03 = clouds generally forming or developing;
04 = visibility reduced by smoke or volcanic ash;
05 = haze;
06 = widespread dust in suspension in the air;
07 = dust or sand raised by wind at or near the station at the
time of observation;
08 = well developed dust whirl(s) seen at or near the station;
09 = dust storm within sight;
10 = mist, steam mist (light fog);
11 = patches of shallow fog, or, from 1966 onward, ice fog;
12 = more or less continuous shallow fog, or, from 1966
onward, ice fog;
13 = lightning visible, no thunder heard;
14 = precipitation within sight, not reaching the ground;
15 = precipitation within sight, reaching the ground or the
surface of the sea, but distant (i.e., estimated to be
more than 5 km from the station);
16 = precipitation within sight, reaching the ground or the
surface of the sea, near to, but not at the station;
17 = thunderstorm, but no precipitation at the station or
within sight;
18 = squall;
19 = funnel cloud;
-----------------------------------------------------------------------
20-29 = precipitation, fog, ice fog, or thunderstorm at the
station during the preceding hour but not at the time of
the observation;
20 = drizzle or snow grains;
21 = rain;
22 = snow;
23 = rain and snow or ice pellets;
24 = freezing drizzle or freezing rain;
25 = showers of rain;
26 = showers of snow, or of rain and snow;
27 = shower of hail, or ice pellets;
28 = fog or ice fog;
29 = thunderstorm;
-----------------------------------------------------------------------
30-39 = dust storm or sandstorm, drifting or blowing snow at
the time of observation;
30 = slight or moderate dust storm or sandstorm subsiding;
31 = slight or moderate dust storm or sandstorm, no
appreciable change during the preceding hour;
32 = slight or moderate dust storm or sandstorm, increasing;
33 = severe dust storm or sandstorm, decreasing;
34 = severe dust storm or sandstorm with no appreciable change;
35 = severe dust storm or sandstorm, increasing;
36 = slight or moderate drifting snow;
37 = heavy drifting snow;
38 = slight or moderate blowing snow;
39 = heavy blowing snow;
-----------------------------------------------------------------------
40-49 = fog or ice fog at the time of observation;
40 = fog or ice fog near the station;
41 = fog or ice fog in patches;
42 = fog or ice fog decreasing, sky discernible;
43 = fog or ice fog decreasing, sky not discernible;
44 = fog, or, from 1966 onward, ice fog; sky discernible; no
appreciable change;
45 = fog, or, from 1966 onward, ice fog; sky not
discernible; no appreciable change;
46 = fog or ice fog, sky discernible, becoming thicker;
47 = fog or ice fog, sky not discernible, becoming thicker;
48 = fog, depositing rime, sky discernible;
49 = fog, depositing rime, sky not discernible;
-----------------------------------------------------------------------
50-59 = drizzle at the station at the time of observation;
50 = drizzle intermittent, slight at time of observation;
51 = drizzle continuous, slight at time of observation;
52 = drizzle intermittent, moderate at time of observation;
53 = drizzle continuous, moderate at time of observation;
54 = drizzle intermittent, heavy at time of observation;
55 = drizzle continuous, heavy at time of observation;
56 = drizzle, freezing, slight;
57 = drizzle, freezing, heavy;
58 = drizzle and rain, moderate or heavy;
59 = drizzle and rain, moderate or heavy;
-----------------------------------------------------------------------
60-69 = rain at the station at the time of observation;
60 = rain intermittent, slight;
61 = rain continuous, slight;
62 = rain intermittent, moderate;
63 = rain continuous, moderate;
64 = rain intermittent, heavy;
65 = rain continuous, heavy;
66 = rain, freezing, slight;
67 = rain, freezing, moderate or heavy;
68 = rain or drizzle and snow, slight;
69 = rain or drizzle and snow, moderate or heavy;
-----------------------------------------------------------------------
70-79 = solid precipitation not in showers at the time of
observation;
70 = intermittent fall of snow flakes, slight;
71 = continuous fall of snow flakes, slight;
72 = intermittent fall of snow flakes, moderate;
73 = continuous fall of snow flakes, moderate;
74 = intermittent fall of snow flakes, heavy;
75 = continuous fall of snow flakes, heavy;
76 = diamond dust;
77 = snow grains;
78 = isolated starlike snow crystals;
79 = ice pellets;
-----------------------------------------------------------------------
80-90 = showery precipitation at the time of observation;
80 = rain shower(s), slight;
81 = rain shower(s), moderate or heavy;
82 = rain shower(s), violent;
83 = shower(s) of rain and snow mixed, slight;
84 = shower(s) of rain and snow mixed, moderate or heavy;
85 = snow shower(s), slight;
86 = snow shower(s), moderate or heavy;
87 = shower(s) of snow pellets or small hail, slight;
88 = shower(s) of snow pellets or small hail, moderate or heavy;
89 = shower(s) of hail, slight;
90 = shower(s) of hail, moderate or heavy;
-----------------------------------------------------------------------
91-99 = thunderstorm during the preceding hour or at the time
of observation;
91 = slight rain at time of observation, thunderstorm during
the preceding hour;
92 = moderate or heavy rain at time of observation,
thunderstorm during the preceding hour;
93 = slight snow or hail at the time of observation,
thunderstorm during the preceding hour;
94 = moderate or heavy snow or hail at the time of
observation, thunderstorm during preceding hour;
95 = thunderstorm, slight or moderate with rain and/or snow
at the time of observation;
96 = thunderstorm, slight or moderate with hail at the time
of observation;
97 = thunderstorm, heavy, with rain or snow at time of
observation;
98 = thunderstorm, combined with dust storm or sandstorm
at time of observation;
99 = thunderstorm, heavy, with hail at the time of
observation (if WWQF = 0; otherwise, the observation
is missing);
WWQF is the quality flag for the present weather observation (0 indicates a valid
observation; 9 indicates a suspect or missing observation);
AIRT is the air temperature (tenths of degrees celsius), measured 2 m above
ground or snow surface level. Observations considered valid may range
from -70.0° to +55.0°C. Missing observations are coded as 9999;
AIRTQF is the quality flag for air temperature (0 indicates a valid observation; 9
indicates a suspect or missing observation);
APH1-APH7 are seven atmospheric phenomena groups, used for reporting various
atmospheric phenomena during the ten minutes preceding the observation
hour. These phenomena are observed visually, as are estimates of their
intensity. Atmospheric phenomena intensity can be weak, moderate or
strong. The phenomena are described by means of codes that are
particular to each of the seven groups. A coded value of 0 indicates that
atmospheric phenomena were not observed at the time of observation.
Additional codes and their meanings are as follows:
APH1 group: 1 = not used;
2 = not used;
3 = dew;
4 = rime;
5 = crystalline frost, grain frost;
6 = glazed frost;
7 = rime and crystalline frost;
8 = rime and glazed frost;
9 = crystalline frost and glazed frost;
APH2 group: 1 = not used before 1966, from 1966 onward: snow haze;
2 = haze;
3 = mist;
4 = ground fog;
5 = crystalline fog, sky visible;
6 = ice fog;
7 = fog, sky visible;
8 = fog;
9 = not used before 1966, from 1966 onward: shallow ice fog;
APH3 group: 1 = drifting dust;
2 = funnel cloud;
3 = dust storm;
4 = whirl;
5 = drifting snow;
6 = blowing snow;
7 = blizzard;
8 = snow storm;
9 = not used;
APH4 group: 1 = before 1966: corona around sun/moon; not used
from 1966 onward;
2 = sunshine;
3 = before 1966: halo around sun/moon; not used from
1966 onward;
4 = snow grains and sunshine;
5 = snow pellets and sunshine;
6 = snow grains;
7 = snow pellets;
8 = ice pellets;
9 = ice pellets and sunshine;
APH5 group: 1 = not used;
2 = glazed rain;
3 = drizzle;
4 = rain;
5 = rain shower;
6 = glazed rain, rain;
7 = glazed rain, rain shower;
8 = not used;
9 = not used;
APH6 group: 1 = not used;
2 = mirage;
3 = ice needles;
4 = snow melting;
5 = snow melting shower;
6 = not used;
7 = snow;
8 = snow shower;
9 = not used;
APH7 group: 1 = not used;
2 = sea soaring (lake or river soaring);
3 = polar lights;
4 = sea soaring and polar lights;
5 = summer lightning;
6 = before 1966, thunderstorm in the distance; not used
from 1966 onward;
7 = thunderstorm;
8 = hail;
9 = thunderstorm and hail;
APH1CF- are the corresponding complement flags for the seven atmospheric
APH7CF phenomena groups. These flags are used to denote whether or not an
observation has been made, and if so, to denote the intensity of the
phenomena. A complement flag of 0 accompanying an atmospheric
phenomena code of 0 means none of the phenomena in a particular group
have been observed. When accompanying a nonzero phenomena code, a
complement flag of 0 denotes phenomena of weak intensity, 1 denotes
moderate intensity, and 2 denotes strong intensity. A complement flag of
9, when accompanied by a quality flag of 9 (see below) indicates a suspect
or missing observation;
APH1QF- are quality flags for the seven atmospheric phenomena groups (0 indicates
APH7QF a valid observation; 9 indicates a suspect or missing observation);
CLDH is the coded value for the high-level cloud type. High clouds are defined
as those with bases higher than 6000 m and include cirrus (Ci),
cirrocumulus (Cc), and cirrostratus (Cs) clouds. Codes have the following
meanings:
0 = cloud type is not indicated, but low- or mid-level clouds
observed, with total cloud amount ranging anywhere from 1/10
to overcast with gaps; high-level clouds are absent or amount
to less than 1/10 sky cover;
1 = Ci;
2 = Cc;
3 = Cs;
4 = Ci and Cc;
5 = Ci and Cs;
6 = Cc and Cs;
7 = Ci, Cc, and Cs;
8 = high cloud presence and type cannot be determined because of
continuous fog or snowstorm; or high-level cloud presence and
type cannot be determined because of overcast conditions at
lower levels;
9 = complete absence of clouds or, in the case of translucent fog,
clear in the zenith (if CLDHQF =0; otherwise the observation
is missing);
CLDHCF is the high-level cloud type complement flag. It is set to 0 when the
high-level cloud type has been determined with no fog present; set to 1
when the high-level cloud type has been determined with translucent fog
or when the high-level cloud type cannot be determined because of
continuous fog; and set to 9 if the high-level cloud type is suspect or
missing.
CLDHQF is the high-level cloud type quality flag (0 indicates a valid observation; 9
indicates a suspect or missing observation);
CLDM is the coded value for the mid-level cloud type. Mid-level clouds are
defined as those with bases between 2000 m and 6000 m; they include
altocumulus (Ac) and altostratus (As) clouds. Codes have the following
meanings:
0 = cloud type is not indicated, but high-level clouds (amount
ranging from 1/10 to overcast) and/or low-level clouds (amount
ranging from 1/10 to overcast with gaps) observed; mid-level
clouds are absent or amount to less than 1/10 sky cover;
1 = Ac;
2 = As;
3 = not used;
4 = Ac and As;
5-7 = not used;
8 = mid-level cloud presence and type cannot be determined due to
fog or snowstorm; or mid-level cloud presence and type cannot
be determined because of overcast at lower levels;
9 = complete absence of clouds or, in the case of translucent fog,
clear in the zenith (if CLDMQF =0; otherwise the observation
is missing);
CLDMQF is the mid-level cloud type quality flag (0 indicates a valid observation;
9 indicates a suspect or missing observation);
CLDL1 is the first of three code groups for describing low-level cloud type.
Low-level clouds are defined as those with bases lower than 2000 m; they
include stratocumulus (Sc), stratus (St), nimbostratus (Ns), cumulus (Cu),
and cumulonimbus (Cb) clouds. Codes have the following meanings:
0 = cloud type is not indicated, but high- or mid-level clouds
observed, with total cloud amount ranging anywhere from 1/10
to overcast; low-level clouds of the CLDL1 group (see below)
are absent or amount to less than 1/10 sky cover;
1 = Cu;
2 = Cb;
3 = not used;
4 = Cu and Cb;
5-7 = not used;
8 = low-level cloud presence and type cannot be determined due to
fog or snowstorm;
9 = complete absence of clouds or, in the case of translucent fog,
clear in the zenith (if CLDL1F =0; otherwise the observation is
missing);
CLDL1F is the low-level cloud type quality flag for the first low-level cloud group
(0 indicates a valid observation; 9 indicates a suspect or missing
observation);
CLDL2 is the second of three code groups for describing low-level cloud type.
Low-level clouds are defined as those with bases lower than 2000 m; they
include stratocumulus (Sc), stratus (St), nimbostratus (Ns), cumulus (Cu),
and cumulonimbus (Cb) clouds. Codes have the following meanings:
0 = cloud type is not indicated, but high- or mid-level clouds
observed, with total cloud amount ranging anywhere from 1/10
to overcast; low-level clouds of the CLDL2 group (see below)
are absent or amount to less than 1/10 sky cover;
1 = St;
2 = Sc;
3 = not used;
4 = St and Sc;
5-7 = not used;
8 = low-level cloud presence and type cannot be determined due to
fog or snowstorm;
9 = complete absence of clouds or, in the case of translucent fog,
clear in the zenith (if CLDL2F =0; otherwise the observation is
missing);
CLDL2F is the low-level cloud type quality flag for the second low-level cloud
group. (0 indicates a valid observation; 9 indicates a suspect or missing
observation.);
CLDL3 is the third of three code groups for describing low-level cloud type.
Low-level clouds are defined as those with bases lower than 2000 m; they
include stratocumulus (Sc), stratus (St), nimbostratus (Ns), cumulus (Cu),
and cumulonimbus (Cb) clouds. Codes have the following meanings:
0 = cloud type is not indicated, but high- or mid-level clouds
observed, with total cloud amount ranging anywhere from 1/10
to overcast; low-level clouds of the CLDL3 group (see below)
are absent or amount to less than 1/10 sky cover;
1 = not used;
2 = Ns;
3 = fractostratus (Fs) and fractocumulus (Fc) of bad weather (also
known as scud);
4-5 = not used;
6 = Ns and Frnb;
7 = not used;
8 = low-level cloud presence and type cannot be determined due to
fog or snowstorm;
9 = complete absence of clouds or, in the case of translucent fog,
clear in the zenith (if CLDL3F =0; otherwise the observation is missing);
CLDL3F is the low-level cloud type quality flag for the third low-level cloud group
(0 indicates a valid observation; 9 indicates a suspect or missing
observation);
WIR is the wind irregularity characteristic. It is a coded value used to describe
the wind speed as steady or gusty and the wind direction as constant or
variable. The wind is considered to be steady if its speed remains
essentially constant over the course of two minutes; otherwise it is
considered gusty. The wind direction is considered constant if over the
course of two minutes it varies within one compass point; otherwise it is
considered to be variable. Observations of this variable are only present in
the 6-hourly data records (i.e., in the pre-1966 data). The 3-hourly records
(1966 onward) contain a value of 9 to indicate missing data. For the pre-
1966 data, a value of 9 is also used to indicate a missing value. Codes for
observations have the following meanings:
0 = no wind;
1 = steady speed, constant direction;
2 = steady, variable;
3 = gusty, constant;
4 = gusty, variable;
5 = characteristic is not defined;
6 = the wind speed and direction at this hour are considered suspect.
WIRF is the wind irregularity characteristic quality flag (0 indicates a valid
observation; 9 indicates a suspect or missing observation).
Razuvaev, V. N., E. G. Apasova, and R. A. Martuganov. 1995. Six- and Three-Hourly Meteorological Observations from 223 USSR Stations. ORNL/CDIAC-66, NDP-048. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee.
Vose, R. S., R. L. Schmoyer, P. M. Steurer, T. C. Peterson, R. Heim, T. R. Karl, and J. K. Eischeid. 1992. The Global Historical Climatology Network: Long-term monthly temperature, precipitation, sea level pressure, and station pressure data. ORNL/CDIAC-53, NDP-041. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee.