ANT-XXVII/4, Weekly Report No. 2
An object without shadow when the sun is at 90° elevation. (photo: Max Miller)
The assembled new cable termination. (photo: E. Dunker)
The disassembled cable termination. (photo: Saad El Naggar)
1 May - 8 May 2011
The South-Easterly trade winds pushed us towards the Equator. This implied advantages and disadvantages. Among the advantages we count that we were able to save a significant amount of very expensive fuel and that the wind conditions on the decks where rather comfortable by cruising with the wind. As disadvantage we had to accept that our scientific programme was disturbed, in particular the collection of air samples. The wind from the back pushed the exhaust gases and most of other ship’s gas emissions towards the aerosol container and contaminated the collected samples. After having passed the Equator, the wind direction changed and the North-Easterly trade winds took over. With this advantageous wind direction the scientists collecting air samples were very satisfied about the clean air masses passing their instrumentations. However, now the relative wind on deck is so strong, that sometimes relative winds of force 9 were reached. So, life is about give and take.
The wind increased after crossing the Equator and so did the sea state. We crossed 17° 7’ N on May 6th at noon time, where the sun elevation was about 90° at zenith (real declination was 16° 24’ N). This is the highest elevation of the sun during our cruise. Under these conditions objects standing in the sun, do not form shadows (Fig. 1). Now the sun’s elevations at zenith will decrease slowly in relation to our positions. We carried out the daily noon station collecting surface water samples by using an inflatable utility boat. Bad weather and sea conditions interrupted the work on May 6th and 7th.
All other programmes are running as planned without any disturbances. The evening programme was continued with talks and presentations. On 7 May we carried out a joint safety drill with crew and scientists both participating in the manoeuvre. Such exercises are essential for the safety on board.
A new cable termination for the 18 mm fibre optical and coax sea cable developed at AWI was successfully tested on May 7th. This modular termination allows the universal use of the sea cable on board without spending significant ship time to transfer it from one winch to the other and without cutting and refitting the expensive connector. The new termination consists of two symmetric parts, which can be easily assembled and disassembled (Fig. 2 and Fig. 3).
All on board are well and greet all those that remained at home including our readers.
On behalf all on board
Saad El Naggar - Chief Scientist