• News
• Archive
• Projects
• Reviews

5.2 Ocean currents and calculations of drift
    
     - Ocean currents (Brief account by Harald Loeng, Institute of Marine Research)
      Objects that drift in the sea follow the direction of the current if they are
      floating low in the water or are more or less submerged. Objects that drift
      lightly on the sea, with ample windage, float predominantly in the direction
      of the wind with little influence from the direction of current. Since the Institute
      of Marine Research knows little or nothing about the wind during the period
      between the accident and the time the objects were found, emphasis in the
      following assessments has been placed primarily on the ocean current.

      Let us first consider the alternative that assumes the accident occurred between
      the mainland and Bjørnøya, most likely on the underwater ridge between the
      Barents Sea and the Norwegian Sea. The enclosed map roughly shows the
      pattern of the currents in the Norwegian Sea. It is possible for objects that drift
      out into the Norwegian Sea to be picked up by currents that first move
      north westwards then gradually turn more and more to the south. These
      currents would turn towards the Norwegian coast and it is therefore quite
      possible that objects can drift from the area around Bjørnøya to the Haltenbanken.
      It is also possible for objects from the same area to drift in towards the coast
      of Troms and Finnmark. The driftwood found along these areas of the coast is an
      example of this.


An accident just off the coast of Troms is not so easy to explain on the basis of ocean currents, because it is difficult to see how objects could have drifted down to the Haltenbanken from this area. In such a case, the wind would have to have played an important role, which is something of which we have no knowledge. The wind has probably played a role irrespective of where the accident took place, because it is difficult to imagine that parts of the wreckage could have reached the Haltenbanken in 4 months without the help of the wind.

Conclusion: Both sites submitted as locations for the accident are possible, given the finds that have been made, but the underwater ridge between Norway and Bjørnøya seems most probable in the light of what we know about the ocean currents. Drift calculations (made by Kjell Johansen, Main Rescue Co-ordination Centre (RCC),  North Norway) With the help of the RCC’s computer programme, drift calculations have been made regarding wreckage that “floats lightly” in the sea. The calculations are based on two positions  74°44’N 018°00’E (in the vicinity of the “Kvitholmen” find) and 72°30’N 018°00’E (estimated position for the “Latham’s” last radio message). Calculations of drift near the Norwegian coast are difficult because the waters are shallow and there are innumerable isles and skerries. The computer programme calculated drift in May/June 2003 compared to the weather in question. Calculations began on May 12 and were concluded on June 9, 2003. Compared with the right kind of weather in the area, the calculations provide a good indication of how current and wind may have influenced the drift of the pontoon and fuel tank from the “Lataham.”

15°E                    20°E	75°N      74°N    73°N    72°N    71°N

Conclusion, drift calculations:  The drift of wreckage both near Bjørnøya and between the Norwegian Sea and Bjørnøya is influenced to a greater extent by wind than by ocean current. In 1928 there was a strong easterly wind between Bjørnøya and the mainland during the days following the accident. At Bjørnøya on 18 June 1928 and for several weeks afterwards, there was only a light easterly wind, but rather heavy seas.

Conclusion “Ocean currents and drift calculations”:

          If the accident had taken place at position 72°30’N 18°E the wind
       may have carried the wreckage against the current, i.e. towards
       the west/south-west. When the wind died down the current would
       once again carry the wreckage eastwards, towards the Norwegian coast.

       On the other hand, if the accident had occurred in the vicinity of
       Bjørnøya, where the wind was calm, the wreckage would have followed
       the current from the outset. As the figure on page 10 shows, a cold
       ocean current moves from the north turning around Bjørnøya from
       east to west, where it meets the Gulf Stream and is pressed
       northwards towards Svalbard again. It is also worth noting that
       the Gulf Stream divides into two in this area. One part of the
       current turns down towards the Norwegian coast and into the
       Barents Sea, while the other moves northwards, to the west of
       Svalbard. In time, wreckage from an accident in the vicinity of
       Bjørnøya may therefore spread across a considerable area, from
       Svalbard to the entire Norwegian coast.