Other relevant info can be found at: http://www.nbs.ac.uk/public/icd/metlog/


The British Antarctic Survey (BAS) maintains a meteorological observing program at several stations in the British Antarctic Territory and in the South Atlantic with archiving of the data undertaken at Cambridge and the Meteorological Office. Surface and upper-air measurements carried out by the Survey in the region commenced at or around the time of the International Geophysical Year in 1956 although records dating back several decades in the Antarctic Peninsula are available (see, for example, Jones and Limbert (1989)). Much of the collected data has been included in an ORACLE computer database at Cambridge over the last few years allowing quick data retrieval. This short report describes the current database holdings with details of the stations, observing practises, period of record, a detailed description of the main parameters in the SYNOP database for less experienced users and examples of how to extract the data using SQL (Structured Query Language), together with information on various other related data on the database, e.g. monthly mean temperature and pressure data for the Antarctic Peninsula and other parts of the continent and the monthly location of the sea ice-open water margin in the Southern Ocean.

Surface SYNOP data is available for 8 stations, namely Deception Island, Grytviken, Adelaide Island, Signy Island, Port Stanley, Rothera Point, Halley (formerly Halley Bay) and Faraday (formerly Argentine Islands). All but the first 3 stations are operational. Those in operation have been located at the same or a nearby site up to the present and, apart from Rothera Point, Signy and Adelaide Island, have consistently carried out observations at 3 hourly intervals. Data for Signy is intermittent and irregular until recently and should be treated with caution from 1984 onward owing to the absence of a trained meteorological observer at the site at most times (see below). Meteorological observations are still undertaken by the Meteorological Office in the Falklands at Mount Pleasant airport but data are only available on the database for Port Stanley. Upper-air observations are currently only undertaken by BAS at Halley but data for Faraday and Port Stanley are also on the database.

The most important change in observing practise has been the changeover from manual to automatic observing systems to do many of the routine synoptic observations. This change occurred in the mid-1980's at Halley and Faraday, and more recently also at Signy Island and Rothera Point, and involved the deployment of SCAWS (Synoptic and Climatological Automatic Weather Station) which was replaced in 1992 with MAWS (Modular Automatic Weather Station). Apart from standard checks to the data, e.g. for extreme values, including those due to equipment malfunction, and incorrect codes, the experience of trained meteorological observers as well as further scrutiny of some of the data suggests that the performance of automatic weather stations and instruments after initial installation has been satisfactory. Instruments are regularly and frequently calibrated. Regular on-site monitoring of the performance of SCAWS and MAWS by observers, including comparisons with measurements from standard meteorological equipment, also appears to have prevented systematic errors in measurement (details of error checking that has been systematically carried out on synoptic observations (but not on upper-air data yet) are noted in Appendix A1). Apart from failure to launch radiosonde balloons due to bad weather, a problem most common at Halley due to high winds, serious problems in upper-air data collection have been confined to Halley. Here, inaccurate wind directions and speeds between 1984 and 1991 have periodically resulted from radio interference to the OMEGA windfinding system under certain weather conditions. Following introduction of radiotheodolite windfinding in 1992 this problem no longer occurs. At present upper-air data should be treated with caution as they have yet to be fully checked.


Description of the tables

Each ORACLE table contains SYNOP data for a number of parameters in column format for each of the standard reporting hours (rows) and at hourly intervals for automatic weather stations. The duration of the records for stations on the database varies. In some cases the stations are no longer operational but for others data may be available for nearby sites not maintained by BAS as noted below. The frequency of observations varies between stations and also at individual stations and, in some cases, not all parameters are recorded (stored as null values in the tables). Prior to the mid-1980's all observations were carried out manually. As noted below automatic weather stations (see below) were introduced after this period at Faraday and Halley, in 1988 at Signy Island and in 1990 at Rothera Point. These automatically log all parameters apart from those that describe weather, cloud, visibility and full date (as specified in section 2.2). 'SYNOP' as well as other ORACLE data bases are all indexed (see below) permitting rapid data retrieval.

Description of each column

In the following, except for OBTIME, information is given on a) what the parameter is (see section 7 and the Meteorological Office "Observer's Handbook" for a detailed description of these), b) the data type of the variable of the form integer (I), real (R) or character (C), c) whether the variable is in measurement or WMO code form, d) how it is measured, e) valid range in case of non-coded data. In d) the information in brackets refers to automatic weather instrumentation. Missing values for all data columns are left as null.


Date variable giving the calendar date and time of the observation in the form YYYY-MON-DD:HH24:MI:SS where YYYY is the year, e.g. 1987, MON is month, e.g. JAN, DD is day, e.g. 21, HH24 is the hour in the 24 hour clock, MI is minutes pas the hour and SS is seconds past the minute (also see indexing below). The default output format of OBTIME is DD-MON-YY.


a) Total cloud amount, b) I, c) oktas (eighths cover), d) visual, e) from 0 to 9 where 0 is clear sky, 8=total cover and 9 is sky obscured.


a) Direction from which wind blows, b) I, c) in tens of degrees from North via East measured to the nearest 10 degrees averaged over 10 minutes (5 minutes for MAWS), d) Munro direction vane (Vector Instruments), e) 0 to 360 where zero denotes calm and values from 1 to 360 give the wind direction where 360 denotes direction from due north. A 999 value indicates direction is variable.


a) Wind speed, b) R, c) in knots (measured to nearest 1 knot averaged over 10 minutes (5 minutes for MAWS), d) Munro cup generator (Vector Instruments) but occasionally subjectively estimated by observer or determined by using hand held equipment, e) 0 to 90 knots.


a) Visibility - "the greatest distance at which an object can be seen" (Meteorological Office Observers Handbook, 1982) from the point of observation, b) C, c) code (90 (less than 50 m) to 99 (greater than 50 km) code format is used), d) manual.


a) Present weather conditions, b) C, c) code, d) manual.


a) Past weather conditions, b) C, c) code (code changed from one to two characters in 1982), d) manual.


a) Mean sea level pressure, b) R, c) measurement to nearest 0.1 mb, d) Kew type or aneroid barometer (aneroid, KDG Setra barometer), e) 930 to 1030 mb.


a) Screen dry bulb temperature (Assman psychrometer at Halley for occasions of wind speed <16 knots up to end of 1986), b) R, c) measurement to nearest 0.1C, d) thermometer (platinum resistance thermometer (PRT), e) 26.3C (at Grytviken) to -55.3C (at Halley).


a) Screen wet bulb temperature, b) R, c) measurement to nearest 0.1C, d) thermometer (determined from PRT and humidity sensor readings (see below), e) range varies between stations.


a) Saturation vapour pressure, b) R, c) measurement in mb and tenths of a mb, (e.g. 49=4.9 mb) d) derived using wet and dry bulb temperature (PRT and humidity sensor readings), e) 0 to 10 mb.


a) Relative humidity, b) I, c) measurement to nearest 1%, d) derived from DRYBULB and WETBULB measurement (PRT and humidity sensor readings), e) 0 to 102%


a) Low cloud amount, b) I, c) as total_cloud_amount, d) manual


a) Type of low cloud, b) C, c) code, d) manual


a) Type of medium cloud, b) C, c) code, d) manual


a) Type of high cloud, b) C, c) code, d) manual


a) Dewpoint temperature, b) R, c) measurement to nearest 0.1C (rounded to nearest whole degree prior to 1st January, 1986), d) derived from dry and wet bulb measurements (PRT and humidity sensor readings), e) varies between stations.


a) Amount of lowest layer of cloud, b) I, c) as total_cloud_amount, d) manual


a) Type of lowest layer of cloud, b) C, c) code, d) manual


a) Height of lowest layer of cloud, b) C, c) code, d) manual


a) Amount of second lowest layer of cloud, b) I, c) as total_cloud_amount, d) manual


a) Type of second lowest layer of cloud, b) C, c) code, d) manual


a) Height of second lowest layer of cloud, b) C, c) code, d) manual


a) Amount of third lowest layer of cloud, b) I, c) code, d) manual


a) Type of third lowest layer of cloud, b) C, c) code, d) manual


a) Height of third lowest layer of cloud, b) C, c) code, d) manual


Source of synoptic observation in character form - one of either "BASYN SYNOP" (manual observation on synoptic reporting hour), "SCAWS SYNOP" (automatic observation on synoptic reporting hour),"SCAWS GMTOB" (automatic observation at other hours available only from AWS). For observations from MAWS substitute MAWS for SCAWS, e.g."MAWS SYNOP". Hourly observations for Halley in 1986 are under review (see section 2.4.2) and are indicated as "SCAWS TEST".

Data availability

Note that cloud observations prior to 1960 (apart from total cloud amount) are under review for all tables.

Faraday 89063 (formerly Argentine Islands, 88952)

a) Location: 6515'S, 6416'W; Alt: 11 m

b) Observations: continuous observations from January 1956 to present at 3 hour intervals (8 observations/day).

c) Equipment history: Manual observation for all parameters prior to installation of SCAWS in April 1985. SCAWS in test phase until end of 1985 and replacing manual observations from January 1986. SCAWS replaced by MAWS in March 1992. MAWS PRT is aspirated.

Halley 89022 (previously known as Halley Bay)

a) Location (as of January 1992): 7553'S, 2604'W; Alt: 37 m

The station is situated on a moving ice shelf and has been periodically relocated over the recording period. Sites have all been located within about 10 km of the present position.

b) Observations: continuous observations from January 1957 to present at 3 hour intervals (8 observations/day). For the period of testing of SCAWS in 1986 manual 3 hourly observations ("BASYN SYNOP") are available on the database (see section 2.2). Data included for other hours in this year is from the automatic equipment.

c) Equipment history: Manual observation for all parameters up to December 1986. Installation of SCAWS in January 1986 and in test phase until end of 1986. SCAWS replaced by MAWS in February 1992. The hourly SCAWS data for 1986 should be treated with caution as it is suspected instruments may have been improperly calibrated. MAWS PRT is aspirated.

Rothera Point 89062

a) Location: 6734'S, 6808'W; Alt: 16 m

b) Observations: continuous observations from March 1976 to present at 6 hour intervals (4 observations/day). Only 2 observations/day (0000 and 1200Z) in 1976. Data gaps in 1976.

c) Equipment history: Manual observation for all parameters prior to installation of MAWS in December 1990. MAWS in test phase until end of 1991 with manual observations of all parameters on the database up to this time.

Adelaide Island 88958

a) Location: 6746'S, 6855'W; Alt: 30 m

b) Observations: continuous observations from May 1962 to December 1975 at 3 hour intervals (8 observations/day).(station relocated to Rothera in 1976).

c) Equipment history: Manual observation for all parameters.

Signy Island 89042

a) Location: 6045'S, 4536'W; Alt: 7 m

b) Observations: continuous observations from January 1956 to December 1969 and January 1982 to present. Observations every 3 hours (8 observations/day) in first period and from January 1989, and every 4 hours (4 observations/day) at other times. Data complete up to 1969. Only wind speed, (no wind direction), pressure and temperature from 1982 to 1987. Infrequent cloud and visibility observations from 1988 to present, and gaps in other parameters due to lack of trained observer.

c) Equipment history: Manual observation for all parameters until SCAWS installed in 1988 and replaced by MAWS in 1992.

Deception Island 88938

a) Location: 6259'S, 60,34'W; Alt: 6 m

b) Observations: continuous observations from January 1959 to December 1967 when station closed. Observations every 3 hours (8 observations/day).

c) Equipment history: Manual observation for all parameters.

Grytviken 88903

a) Location: 5416'S, 3630'W; Alt: 2 m

b) Observations: continuous observations from January 1959 to December 1981 (with station closed in March 1982). Observations every 3 hours (8 observations/day) from 1959 to 1966 and from 1971 onward; otherwise every 6 hours (4 observations/day). Gaps in visibility and cloud observations from 1967 to 1970.

c) Equipment history: Manual observation for all parameters.

Port Stanley 88890

a) Location: 5142'S, 5752'W; Alt: 51 m

b) Observations: start in January 1958 and end in December 1967 on the database (although this station remained open until April 1982 and subsequently relocated to Mount Pleasant airport in 1984 under the Meteorological Office). Observations made every 3 hours(8/day).

c) Equipment history: Manual observation for all parameters.


Description of the tables

Upper-air data for each station is stored in five tables containing geopotential height, temperature, relative humidity and wind direction and speed at standard pressure levels between 1000 and 10 mb. The standard time of ascents is 1200Z but can be up to 2 hours earlier than this at times. The table names are in the form: _temp_ where parameter is 'height' (geopotential height), 'humidity' (relative humidity), 'temperature' (temperature), 'wind_direction' (wind direction) and 'wind_speed' (wind speed). Missing values are indicated as null.

Description of each column

In the following I = integer and R = real.

In general there are 25 columns in each table. The 'OBTIME' is given in the first column and is of identical form to that used in the SYNOP database (see section 2.2). 24 columns in each of the five tables are to allow for measurements of the different variables at the surface with variable name 'SURFACE', and the following standard pressure levels: 1000, 900, 850, 800, 700, 600, 500, 400, 300, 250, 200, 150, 100, 80, 70, 60, 50, 40, 30, 25, 20, 15, 10 mb. Measurements taken at the tropopause are included in the final column with the variable name 'TROP'. The variable name of each of the standard levels is a 'P' followed by the standard pressure level, e.g. P300. For Halley an additional column is included for measurements at 925 mb made from 1990 onward. Prior to 1984 the surface elevation is given in the SURFACE parameter but the pressure at launch is supplied from 1984 onward.

Prior to 1961 the standard levels above 100 mb were at 80, 60, 50, 40, 30, 25 and 20 mb but then changed to 70, 50, 30, 25, 20, 15 and 10 mb. The geopotential height (I) is to nearest metre, temperature (R) to nearest 0.1C, humidity (I) to nearest 1%, wind direction (I) to nearest whole degree and wind speed (R) to nearest 0.5 knot.

Data availability


a) Observations: The database contains observations from January 1956 to December 1982 when ascents ceased (following a fire at the station). The Faraday database is under review but is mostly complete up to 1975. Data need to be checked for superadiabatic layers and hydrostatic balance before use.

b) Flight frequency: once daily (occasional additional flights made at other times for special studies).

c) Equipment history.

Radiosondes used:

Jan. 1956-Feb. 1971 :  UK Met. Office MkIIb
Mar. 1971-Feb. 1975 :  Graw M60
Mar. 1975-Jan. 1983 :  VIZ (Beukers)


Jul. 1954-Jan. 1963 :  Pilot balloon theodolite
Apr. 1962-Jan. 1983 :  Radar


a) Observations: The database is under review but contains mostly complete observations from the start of observations in April 1957 up to 1974 as well as from 1984 onward. The geopotential height of the 1000 mb standard pressure level is estimated from the measured geopotential height for adjacent standard levels using the hydrostatic equation. Null values appear in the tables for a number of reasons including occasional failure to launch balloons - due to adverse weather conditions (most common in winter) - and to track balloons, as well as early bursting of balloons. Data for 900, 800 and 600 mb have not been computed for 1984 to 1989. Incorrect wind measurements occur during the period using OMEGA windfinding equipment (see section (c)). Quality control of these data is not yet complete and other errors are known to exist. Data should be checked for superadiabatic layers and hydrostatic balance before use.

b) Flight frequency: once daily (with occasional additional flights made for special studies at non-standard times).

c) Equipment history

Radiosondes used:

Apr. 1957-Feb. 1971 :  UK Met. Office MkIIb
Mar. 1971-Feb. 1975 :  Graw M60
Mar. 1975-Dec. 1983 :  VIZ (Beukers)
Feb. 1984-Dec. 1991 :  Vaisala RS80     
Jan. 1992-present   :  AIR Intellisonde  


Apr. 1957-Aug. 1981 :  Radar
Aug. 1981-Feb. 1984 :  Pilot balloon theodolite
Feb. 1984-Dec. 1991 :  OMEGA navaid       
Jan. 1992-present   :  Radiotheodolite 

Port Stanley

a) Observations: start in January 1956 and available on the database until February 1968 (observations recommenced in 1984 at Mount Pleasant airfield - see section 2.4.8). Quality control of these data is not yet complete and some errors are known to exist. Data should be checked for superadiabatic layers and hydrostatic balance before use.

b) Flight frequency: daily at 1200Z but only every 2 or 3 days in the latter part of the database.

c) Equipment history

Radiosondes used: UK Met. Office MkIIb; Windfinding: Radar



The tables contain the 3 hourly measurements of temperature, pressure, wind speed and wind direction for the automatic weather stations, that are deployed by the US, in the Antarctic. The table names are specified as NAME_AWS and the locations and periods for which we have data are shown below.

AWS  NAME        FROM       TO         LAT      LONG    HT(m)

AGO_SITE         01-JAN-91  31-DEC-92  77 31'S  23 44'W 1545      
ALLISON          28-JAN-86  31-JUL-87  89 53'S  60 00'W 2835
ASGARD           05-FEB-80  31-DEC-82  77 36'S 160 06'E 1750
BONAPART_POINT   01-JAN-92  31-DEC-92  64 47'S  63 04'W    8
BOWERS           11-JAN-86  25-AUG-86  85 12'S 163 24'E 2090     
BUCKLE_ISLAND    01-JAN-87  31-JUL-88  66 54'S 163 12'E  520
BUTLER_ISLAND    01-MAR-86  31-DEC-92  72 13'S  60 20'W   91
BYRD             05-FEB-80  07-OCT-92  80 00'S 120 00'W 1530
BYRD_GLACIER     01-JAN-84  31-AUG-84  80 00'S 165 02'E   75
CAPE_ADAMS       29-JAN-89  22-SEP-92  75 01'S  62 32'W   25
CAPE_DENISON     01-JAN-90  31-DEC-91  67 01'S 142 41'E   31
CLEAN_AIR        01-JAN-86  31-JAN-91  89 57'S  00 01'W 2835
DOLLEMAN_ISLAND  01-JAN-87  31-DEC-88  70 36'S  61 00'W  396
DOME_C           05-FEB-80  31-DEC-92  74 30'S 123 00'E 3280
D_10             08-JAN-80  31-DEC-92  66 42'S 139 43'E  240
D_17             11-JAN-80  19-JUN-80  66 42'S 139 42'E  438
D_47             01-JAN-83  31-DEC-92  67 23'S 138 43'E 1560
D_57             01-JAN-81  31-DEC-87  68 11'S 137 31'E 2105
D_80             14-JAN-83  30-SEP-90  70 01'S 134 43'E 2500
ELAINE           28-JAN-86  17-SEP-88  83 09'S 174 28'E   60
FERRELL          10-DEC-80  27-AUG-92  78 01'S 170 48'E   45
FOGLE            25-JAN-84  05-JAN-85  77 49'S 166 45'E  202
GILL             01-JAN-85  31-DEC-92  80 02'S 178 38'W   55
JIMMY            02-DEC-81  30-APR-90  77 52'S 166 49'E  200
LARSEN_ICE       01-JAN-86  31-DEC-92  66 58'S  60 33'W   17
LAURIE           12-DEC-81  31-DEC-85  77 33'S 170 05'E   23
LETTAU           29-JAN-86  31-DEC-92  82 35'S 174 16'W   55
LINDA            01-JAN-91  30-APR-92  78 30'S 168 21'E   50
LYNN             01-JAN-88  31-DEC-92  74 14'S 160 17'E 1772
MANNING          01-DEC-80  31-DEC-85  78 46'S 166 51'E   66
MANUELA          01-JAN-84  31-DEC-92  74 53'S 163 36'E   80
MARBLE_POINT     05-FEB-80  31-DEC-92  77 26'S 163 45'E  120
MARILYN          01-JAN-87  31-DEC-92  79 57'S 164 58'E   75
MARTHA1          01-JAN-84  31-DEC-86  78 18'S  72 30'E   20
MARTHA2          21-JAN-87  13-FEB-92  78 23'S 173 22'W   18
MEELEY           01-JAN-81  31-DEC-85  78 15'S 170 11'E   49
MINNA_BLUFF      01-JAN-91  31-DEC-92  78 33'S 166 41'E  917
MT_EREBUS        01-DEC-89  16-OCT-90  77 32'S 167 09'E 3700
MT_HOWE          01-JAN-92  31-OCT-92  87 19'S 149 33'W 2400
NANCY            17-JAN-83  25-NOV-83  77 55'S 168 10'E   25
PATRICK          28-JAN-86  26-JUN-87  89 54'S  45 00'E 2835
PAT              01-JAN-89  31-DEC-90  74 53'S 163 06'E   30
PEGASUS          19-JAN-89  10-NOV-89  78 00'S 166 38'E   50
PEGASUS_NORTH    01-JAN-90  31-DEC-92  77 57'S 166 31'E   10
PEGASUS_SOUTH    01-JAN-91  31-JAN-91  78 02'S 166 36'E   10
PENGUIN_POINT    01-DEC-92  31-DEC-92  67 37'S 146 00'E   30
PORT_MARTIN      01-JAN-90  31-DEC-91  67 12'S 141 26'E   15
RACER_ROCK       01-OCT-89  31-DEC-92  64 16'S  61 54'W   17
SANDRA           01-JAN-89  31-DEC-92  74 29'S 160 29'E 1525
SCHWERDTFEGER    01-JAN-85  30-SEP-92  79 56'S 169 50'E   60
SCOTT_ISLAND     01-JAN-88  31-JAN-91  67 22'S 179 58'E   30
SHRISTI          01-JAN-88  30-SEP-92  74 42'S 161 34'E 1200
SIPLE            01-JAN-82  21-APR-92  75 54'S  84 00'W 1054
SUSHILA          01-JAN-88  30-SEP-91  74 25'S 161 19'E 1430
TIFFANY          24-JAN-84  31-DEC-85  78 00'S 168 12'E   25
URANUS_GLACIER   01-MAR-86  30-NOV-92  71 26'S  68 56'W  780
WHITLOCK         01-JAN-82  31-JAN-92  76 14'S 168 42'E  275
WILLIS_FIELD     25-JAN-92  30-NOV-92  77 07'S 167 00'E   20
WINDLESS_BIGHT   01-JAN-83  31-DEC-85  77 45'S 167 40'E   40
YOUNG_ISLAND     01-JAN-91  31-DEC-92  66 17'S 162 20'E   30

Data source

The data is collected and quality controlled by the University of Wisconsin. No further error checking has been carried out . The potential inaccuracies of data from unmanned weather stations must be borne in mind and users should carry out their own data checks.

Table organisation

The tables contain 5 columns obtime, temperature, pressure, wind_speed and wind_direction. The wind speed is in m/s.



There are two tables GTS_SYNOP and GTS_TEMP containing synoptic and upper-air reports from most of the bases in the Antarctic. The bases and periods covered are shown below.


Station Station Name     From         To

85934   Punta            01-DEC-93    30-SEP-94     
88889   MPA              01-DEC-93    30-SEP-94     
89001   S.A.N.A.E        16-NOV-87    27-NOV-92     
89002   G von Neumayer   21-DEC-87    30-SEP-94     
89009   Amundsen-Scott   16-NOV-87    30-SEP-94     
89022   Halley           16-NOV-87    30-SEP-94     
89050   Bellingshausen   17-NOV-87    30-SEP-94     
89055   Marambio         23-NOV-87    30-SEP-94     
89512   Novolazarevskaya 16-NOV-87    29-FEB-92     
89532   Syowa            16-NOV-87    30-SEP-94     
89542   Molodeznaja      16-NOV-87    22-APR-94     
89564   Mawson           16-NOV-87    30-SEP-94     
89571   Davis            16-NOV-87    29-SEP-94     
89592   Mirnij           16-NOV-87    30-SEP-94     
89606   Vostok           16-NOV-87    07-JAN-92     
89611   Casey            16-NOV-87    30-SEP-94     
89642   Dumont D'urville 16-NOV-87    29-SEP-94     
89657   Leningradskaja   16-NOV-87    31-DEC-90     
89664   McMurdo          17-NOV-87    30-SEP-94     


Station Station Name      From         To

85934   Punta             01-JAN-88    30-SEP-94
87925   Rio Gallegos      01-JAN-88    30-SEP-94
87938   Ushaia            01-JAN-88    30-SEP-94
88889   MPA               01-JAN-88    30-SEP-94
88903   Grytviken         01-JAN-88    30-SEP-94
88963   Esperenza         01-JAN-88    30-SEP-94
88968   Orcadas           01-JAN-88    30-SEP-94
89001   S.A.N.A.E         01-JAN-88    17-NOV-92
89002   G von Neumayer    01-JAN-88    30-SEP-94
89009   Amundsen-Scott    01-JAN-88    30-SEP-94
89022   Halley            01-JAN-88    30-SEP-94
89024   AGO1 (AWS)        24-SEP-91    19-JUL-93
89034   Belgrano          12-DEC-93    30-SEP-94
89042   Signy             02-JAN-88    30-SEP-94
89050   Bellingshausen    01-JAN-88    30-SEP-94
89053   Jubany            12-DEC-93    30-SEP-94
89054   Dinamet           12-DEC-93    30-SEP-94
89055   Marambio          01-JAN-88    30-SEP-94
89056   Frei              01-JAN-88    30-SEP-94
89057   Aruro Prat        12-DEC-93    30-SEP-94
89058   Great Wall        12-DEC-93    30-SEP-94
89059   Bernado O'Higgins 12-DEC-93    30-SEP-94
89061   Palmer            12-DEC-93    30-SEP-94
89062   Rothera           01-JAN-88    30-SEP-94
89063   Faraday           01-JAN-88    30-SEP-94
89065   Fossil Bluff      01-JAN-88    21-FEB-94
89066   San Martin        01-JAN-88    30-SEP-94
89251   King Sejong       12-DEC-93    30-SEP-94
89261   Racer Rock (AWS)  26-JUL-89    30-SEP-94
89262   Larsen (AWS)      16-JAN-89    30-SEP-94
89264   Uranus Gl.(AWS)   16-JAN-89    02-FEB-94
89266   Butler Is. (AWS)  16-JAN-89    30-SEP-94
89268   Cape Adams (AWS)  26-JUL-90    22-SEP-92
89284   Siple (AWS)       25-JUL-90    19-JUL-93
89324   Byrd (AWS)        16-JAN-89    30-SEP-94
89512   Novolazarevskaya  01-JAN-88    30-SEP-94
89532   Syowa             01-JAN-88    30-SEP-94
89542   Molodeznaja       01-JAN-88    30-SEP-94
89564   Mawson            01-JAN-88    30-SEP-94
89571   Davis             01-JAN-88    30-SEP-94
89573   Zhongshan         12-DEC-93    30-SEP-94
89592   Mirnij            01-JAN-88    30-SEP-94
89606   Vostok            01-JAN-88    09-FEB-94
89611   Casey             01-JAN-88    30-SEP-94
89642   Dumont D'urville  01-JAN-88    30-SEP-94
89657   Leningradskaja    01-JAN-88    27-MAR-91
89664   McMurdo           01-JAN-88    30-SEP-94
89705   AGO1 (AWS)        01-SEP-93    30-SEP-94
89828   Dome C (AWS)      16-JAN-89    30-SEP-94
89832   D-10 (AWS)        31-JUL-89    30-SEP-94
89834   D-47 (AWS)        09-OCT-91    30-SEP-94
89836   D-80 (AWS)        25-JUL-90    30-SEP-94


All the data was received over the Global Telecommunications System (GTS). The data is incomplete for all stations and has been collected primarily for intensive study of short periods; great care should be taken if working out long term mean values.

Reports are recieved at 3 or 6 hourly intervals depending on the station. Range error checking has been carried out on the data.



The table "jones_and_limbert" contains the mean monthly values of temperature and mean sea level pressure or station pressure compiled for 30 stations throughout Antarctica by Jones and Limbert (1989). The length of record varies between stations but mostly dates from the 1950's and 60's and, apart from the British Antarctic Survey sites in the Peninsula and at Halley, are to as recently as 1988. Means for those Antarctic Survey stations still in operation have been updated to June 1993.

Data sources

The data sources used by Jones and Limbert (1989) mainly consisted of the World Weather Records covering the period 1951 to 1979 and Monthly Climate Data for the World for the period from 1961 to 1988. Records from adjacent stations for different periods were composited into single "station" records such as for Rothera Point (see sections 2.4.3 and 2.4.4). Station reports have been used to update the monthly means to June 1993 for the BAS stations that continued to operate after 1988. More information on data sources and stations included as well as details of station compositing can be found in Jones and Limbert (1989).

Table organization

The table contains 5 columns: STATION (character), OBTIME(date), DAY_NUMBER(integer), PRESSURE(real to nearest 0.1 mb) and TEMPERATURE(real to nearest 0.1C). DAY_NUMBER is the day number where day 0 is the 1st January, 1960 (day number is therefore an increasing negative number going back from this date), and where the day number for a particular monthly mean is for the first day of that month. OBTIME form is DD-MON-YY.



The table "ice_edge" gives the monthly northern limit of the icepack in the Southern Ocean from 1973 to 1991 at 10 degree intervals starting at 0E and finishing at 350W derived by Jacka (1990). The position of the icepack limit is for the middle of the month. The table "SIGRID" gives the corrosponding weekly northern limit of the icepack in the Southern Ocean from 1973 to 1988 at 1 degree intervals.

Data sources

Data in both these tables is based on the Weekly ice charts produced by the Navy/NOAA Joint Ice Center derived primarily from satellite passive microwave measurements and visible and infra-red imagery, but also incorporating ship and any other available observations. The limit of the ice is taken as where the ice concentration is less than 10%.

Table organization

The table contains 4 columns: OBTIME(date), SASDAY(integer), LONGITUDE(integer) and LATITUDE(real to nearest 0.1C). OBTIME form is DD-MON- YY. SASDAY is in the same form as DAY_NUMBER in the "jones_and_limbert" table.



Hourly radiation and sunshine duration measurements are available for the BAS sites at Halley and Faraday, both from 1986 onward, and for Signy Island from 1988 to date. Locations of the sites are noted in section 2. The table names are in the form: _radiation, e.g. halley_radiation.

Data sources

BAS automatic weather station and observational data.

Table organization

Tables contain 5 columns: OBTIME(date) in DD-MON-YY (note hour is not included), GMT - Greenwich mean time in HH form, e.g. 1300 is 1 PM, LAT giving the Local Apparent Time also in HH form, SUN - the duration (minutes) of sunshine in the hour proceeding the observation, e.g. from 1200 to 1300 GMT, TOTAL_SUN - the total duration of sunshine in the current day up to the hour of observation, RADIATION - solar radiation(wm-2) based on an average for the 60 minutes prior to the observation, UV (wm-2) - U.V radiation averaged for the 60 minutes prior to the hour of the observation and TEMPERATURE - temperature averaged over the 60 minutes before the observation.

Apart from temperature readings, all the parameters (except OBTIME that is in date form) are in integer format. Temperature is a real measurement to the nearest 0.1C. Radiation and sunshine instruments are as follows:

Solar radiation : Solarimeter Ultra-violet radiation : Eppley ultra-violet radiometer Sunshine : Haenni sunshine detector


The following notes are intended to provide the inexperienced user with more information on those parameters in the SYNOP database that are most likely to be used. They should be used in conjunction with the description of the different meteorological parameters and coding given in section 2. Please contact the database manager if you need any more information.

Temperature measurement:

Air temperature measurements are made by conventional thermometers and platinum resistance thermometers (PRT) housed in a Stevenson screen. The wet bulb temperature (or ice bulb temperature for temperatures below freezing) is used to calculate relative humidity, a measure of the water content of the air as a fraction of the total water content if the air was saturated. Wet and dry bulb readings are also used to determine the dew point temperature and saturation vapour pressure. Following introduction of automatic observing systems the various temperature measurements are now obtained using the humidity probe and PRT readings.

Screen temperatures can occasionally exceed ambient air temperatures. This problem, associated with a screen situated above a permanent snow/ice covered surface, arises from a lack of ventilation of the screen in calm conditions with solar radiation (direct and reflected from the surface) warming the screen compared to its surrounds. This situation occurs at Halley and the MAWS equipment here is now aspirated. Prior to introduction of SCAWS, Assman psychrometers were used at Halley to estimate temperatures at wind speeds below 16 knots. No aspiration was done during the SCAWS era and analysis of the dry bulb temperature data at low wind speeds indicates a higher frequency of temperatures above freezing from SCAWS compared to previous years and apparent record high maxima in the summer months.

Cloud type:

The total_cloud_amount, low_cloud_amount, etc indicate the amount of sky covered by cloud or a particular type of cloud, e.g. cumulus, cirrus. The amount is given in eighths (oktas) i.e. 1= one eighth. For many purposes a value of "9" in the amount column may be treated as an "8", i.e. overcast, since there is no sun reaching the surface. A "9" indicates the sky is obscured, e.g. due to fog.

The codes for the type of cloud in the "cloud_type" categories are:

        0  - Cirrus
        1  - Cirrocumulus
        2  - Cirrostratus
        3  - Altocumulus
        4  - Altostratus
        5  - Nimbostratus
        6  - Stratocumulus
        7  - Stratus
        8  - Cumulus
        9  - Cumulonimbus
        /  - Cloud not visible owing to darkness, storm, fog etc

Height of cloud:

The height of cloud is the height of the cloud estimated from the ground surface to cloud base. The coding used for the "first_cloud_height", "second_cloud_height" and "third_cloud_height", of which the "first" is the lowest, is

        00   <100 ft
        01    100 ft
        02    200 ft
        50   5000 ft 
Codes 51 to 55 are not used. For codes from 56 to 80 subtract 50 from the code and multiply by 1000, so

        56   6000 ft
        57   7000 ft
        80  30000 ft 
        81  35000 ft
        82  40000 ft
        83  45000 ft
        84  50000 ft
        85  55000 ft
        86  60000 ft
        87  65000 ft
        88  70000 ft
        89 >70000 ft


Codes for the different distances are:

       90 : < 50 m
       91 :   50 m
       92 :  200 m
       93 :  500 m
       94 :    1 km
       95 :    2 km
       96 :    4 km 
       97 :   10 km
       98 :   20 km 
       99 : =>50 km


This is the pressure reduced to sea level in mb, not the station pressure.


In meteorology wind direction always refers to the direction from which the wind is blowing. Wind speed in the BAS database is always given in KNOTS.


Sunshine is the total duration of sunshine at the surface in a given time period.


The measured total incoming solar and U.V radiation at the surface averaged over a specified period of time.


The following gives a short summary of the main error checking applied to synoptic observations. These errors include those that arise from mistyping with resulting mistakes in computation of some other related parameters. Values were corrected by entering those recorded in the original meteorological registers and by recomputation.

Wind Speed:

Wind speed > 50 knots compared with visibility and present weather.

In cases where the visibility, for example, is higher than expected the apparent high speeds are checked in the register.

Wind Direction:

Wind direction <0 or >360 degrees. Missing values (999) appear when the direction is highly variable such that a representative 10 minute average cannot be obtained.


Values checked to be in range 90-99; cross-checking with visibility and present weather.


5 consecutive pressures selected and if the difference between readings 2 and 3 and the difference between 3 and 4 exceeds the difference between 1 and 2 or between 4 and 5, readings 2,3 and 4 (the intermediate ones) are checked.


Dry bulb temperature checked against the extreme recorded maximum and minimum for each station (errors mainly occur in the sign due to mistyping).

Wet(ice) bulb and dew-point temperature < dry bulb temperature. Checking for valid cases of super saturation achieved by adding 1C to the dry bulb values to make them higher than wet(ice) bulb reading; remaining cases in which the wet(ice) bulb temperature is warmer than the dry bulb are then taken to be erroneous, the wet bulb temperature is set to equal the dry bulb temperature and relative humidity is set to 100%. Corrections made for incorrect signs, i.e. positive temperatures that should be negative, for cases of wrongly calculated dew-point temperature using wet and dry bulb readings and for incorrect wet-bulb temperature using dry and dew-point readings.

Vapour pressure and relative humidity:

RH < 103% New RH values inserted in cases with corrected temperature readings.

Saturation vapour pressure obtained using the Goff-Gratch equations.

Cloud observations:

Total amount of low cloud > total cloud amount. Repeated in order for second and third cloud amounts. Checking of cloud height and cross-checking of cloud observations with weather conditions now in progress.

List of ORACLE Meteorological Tables


Various other items are contained in the following tables for which more details may be obtained from the database manager:

'stations' - list of meteorological stations in Antarctica including station coordinates, elevation and station number details.

'iceberg' - recorded positions of icebergs in the Southern Ocean

'ice_edge_norms' - climatological mean monthly positions of the sea ice edge in the Southern Ocean derived from the table 'ice_edge'.