1. TEMPERATURE, SALINITY AND DENSITY OF THE SURFACE LAYER OF SEA WATER.
This description below is based on the original one from AARI (See Expl.doc).
The source tables referred to are included in the Data_1.xls spreadsheet in the
\INSROP_GIS\Sourcedata\AARI-SOF 1996\tables folder.
1.1. A brief description of initial data.
Data of the Russian ship- and airborne expeditions in the Arctic Seas for the
period 1960-1994 were used. The shipborne expeditions were conducted from late
July to early October over the ice-free sea areas. The airborne expeditions
were carried out from March to May (the most favourable period for aircraft
landing on the drifting ice). The observations at the polar stations were used as an
additional source of the initial data. The distribution of shipborne
observations both in space and in time is distinguished by a large non-uniformity. In
connection with the significant seasonal and interannual variability of ice
conditions, the number of observations significantly varies both from year-to-year
and during the same years in various regions. The East-Siberian Sea, which is
characterised by more severe ice conditions, is quite poorly covered. The airborne
hydrological observations are also non-uniformly distributed in space and in
time. This is related to different possibilities for conducting them in various
years (organisation problems, weather and ice). The observation interval in
space in the summertime is 10-60 km, in the wintertime - 50-250 km.
For water temperature measurements, deep-sea reversing thermometers were used.
The accuracy of temperature determination is 0.01° C.
For salinity determination during ship- and airborne expeditions two methods
were used: the electromagnetic method (based on determination of electrical
conductivity of a sea water sample by means of an electrical salinometer GM-65) and
the Knudsen's method (based on determination of chlor content in a sea water
sample by titration). The accuracy of salinity determination is 0.01 per mil.
Sea water density values were calculated from data on temperature and salinity
using the methods approved by UNESCO in 1983 with an accuracy up to 0.01.
1.2. A brief description of the processing/analysis method.
For obtaining temperature, salinity and density values at the prescribed
points, the information sets of observation data were formed. These sets were used
for constructing mean monthly fields in the form of charts for each year. The
values of the characteristics at the prescribed points were taken from the
charts. The occurrence frequency of the ranges of mean seasonal temperature, salinity
and density values was calculated on the basis of the obtained series. The
number of the ranges were selected in each specific case depending on the
variability and the number of observations.
1.3. A brief description of the data transferred.
The tables of the occurrence frequency of the ranges of mean seasonal values
of temperature, salinity and density in the sea water surface layer were
calculated for points 2 to 23 (the Kara, Laptev, East-Siberian and Chukchi Seas) for
the following seasons: the season of the development of spring processes (July)
the season of the development of summer processes (August), the season of
stable summer processes (September), the season of the development of autumn
processes (October), the winter season (March-May). For points 24 and 25 (the Barents
Sea) the following seasons were used: the spring season (June); the summer
season (July-September); the autumn season (October); the season of the development
of winter processes (November - December); the season of stable winter
processes (January-May). The differences in the seasonal presentation of information
are explained by the fact that the hydrological regime of the Barents Sea
significantly differs from that of the Kara, Laptev, East-Siberian and Chukchi Seas.
The calculation results are transferred in the form of three ASCII files
(tbl_2.txt, tbl_3.txt and tbl_4.txt), containing Table 2 (occurrence frequency of
the ranges of sea surface temperature), Table 3 (occurrence frequency of the
ranges of salinity of the surface layer) and Table 4 (occurrence frequency of the
ranges of density of the surface layer).
The tables consist of the records, which include the following fields: No. of
the point; the month of the beginning of the period of averaging; the month of
the end of the period of averaging; the lower limit of the range of the
characteristic; the upper limit of the range of the characteristic; the number of
cases in the range; the occurrence frequency (%).
In some cases, initial information necessary for estimating the distribution
of the values of hydrological characteristics, is absent in a given region at a
given time. In connection with this, the tables have the occurrence frequency
values calculated from a non-representative sampling.
Path: <NSR_DATA>\oceanriv\aari_sof
Table type: dBASE table.
* Sea surface temperature
685 records, 8 descriptive fields.
Fields: [<Name>] -- <Alias> (type of field)
[Location] -- "Location" (Numeric, no decimals)
ID number for the location
[Month_1] -- "First month in season" (Numeric, no decimals)
First month in season
[Month_2] -- "Last month in season" (Numeric, no decimals)
Last month in season
[Ll] -- "Lower limit (°C)" (Numeric, 2 decimals)
Lower limit (°C)
[Lu] -- "Upper limit (°C)" (Numeric, 2 decimals)
Upper limit (°C)
[Ll_ul] -- "Range" (String, max. 11 characters)
Lower limit - Upper limit
[N] -- "No. of observations" (Numeric, no decimals)
No. of observations
[Fr] -- "Frequency of occurrence (%)" (Numeric, 1 decimal)
Frequency of occurrence (%)
Sea surface temperature