The south-western Barents Sea may lie far to the north, but the heating effect of the Gulf Stream means that it is far warmer than other areas at the same latitude. But the eastern and northern parts of these waters are not affected by the warm current, and thereby remain colder.
Winter temperatures in the southern and western Barents Sea – in other words, close to the coast of Norway’s Finnmark county – can creep down towards -20°C.
Design temperatures for the producing Snøhvit field and the area around the Johan Castberg discovery are -17.5°C and -18°C respectively.
The northern part of the newly-opened Barents Sea South East area can experience temperatures down to -25°C or -30°C. Even further north, towards the southern tip of Svalbard, the thermometer can drop below -40°C.
Reading from the thermometer alone, temperatures in those areas of the Norwegian far north with current petroleum operations do not appear to be that extreme. The lowest figure ever recorded in mainland Norway, for example, is -51.4°C, measured at Karasjok in central Finnmark as long ago as 1886.
Taking the wind chill factor into account immediately makes conditions in the Barents Sea much tougher.
A wind chill scale is used to convert temperature and wind conditions from actual to perceived cold. This kind of index is also used to calculate the risk of cold-related injuries.
Cold combined with high wind increases the incidence of icing, when spray, supercooled rain or wet snow freeze to vessels or installations. This phenomenon primarily occurs in areas close to the coast, when strong winds blowing from the south and south-east combine with low temperatures.
A coating of ice can stop production equipment working or destroy it, freeze personal protective gear or safety devices, or render a vessel unstable. Icing is a well-known problem in the aviation industry, since the extra weight on wings and fuselage can pose a big threat to staying aloft.
Around Bear Island, roughly midway between Svalbard and the Norwegian mainland, the average sea surface temperature is 1.46°C from January to March and 3.43°C from June to August.
Temperature is very significant for staying alive in the sea. The colder the water, the faster hypothermia sets in. Just a few degrees makes a big difference. Special survival suits have accordingly been designed for use on Norwegian offshore facilities operating in the far north.
People in the cold
The far-northern climate can expose workers to extreme cold. Research shows that illness or injury can occur as a direct consequence of such exposure. Such outcomes include, for example, a sharp increase in cases of frostbite once temperatures fall below -10°C.
Work performance also falls in very cold conditions. Mental, emotional and motor abilities all decline, increasing the risk of work-related accidents.
Exposure to cold boosts the threat of: