Sven's Blog

Long time no update here…Last Monday we arrived in Tromso, where the crew almost completely changed. We left land again at around six. Since then we were heading to the west, trying to find the west end of fish occurrences. As the weather was rather nice, a very calm sea though foggy and cloudy we decided to head directly towards Greenland. So today we arrived near the coast of Greenland and spotted two nice icebergs as well as what we think of as a mine, though one cannot be too sure if is not a buoy…The west end of the herring stock can now be determined with an accuracy of app. 60 miles, which is not too bad…The cruise track changed again a little bit just now and we are heading northwest of Iceland straight into the big mackerel area which is rather unluckily famous at the moment. Well that is one reason and the other one is the more scientific one we want to get a good view of the Greenland coast! 
Yesterday evening we spotted a seal in the water with some strange behaviour. Whale observations were rather lower then expected probably due to the very foggy weather conditions.

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I finally managed to get logbook information, catch data and ctd data into Eonfusion, also acoustic echograms with bubbles where fish was recognised are visible now and the cruise track as van be seen on the picture, with position of stations can directly be transformed into a kmz google earth file, so evertime i update the data, the position will be updated too…

View Larger Map

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Today we were passing the impressive island of Jan Mayen between the Greenland and Norwegian Sea, an impressive sight, even ameliorated by a couple of whale sightings, including a couple of notable breachings of a humpback and a nice sighting of a fin whale just next to the vessel. The vessel was changed for a couple of hours into more of a tourist boat with photo clicks at each ping of the echosounder. One can’t help wondering how it must feel to live on this kind of very isolated island, where LIBAS got stranded just 2 years ago.
A part from this work was also progressing. I managed to write yet another script to compile catch data into a useable format, and exported scrutinised data from LSSS was successfully integrated into Eonfusion. Yesterday progress was also achieved on the CTD and current data, not yet perfect but we are on the track. A few more code snippets in Eonfusion, with a couple of deep dives into C# should do the job…So for tomorrow definetely scrutinising of acoustic data has to be done and some work on current data. For the rest writing up should get a real start and not being pushed further off anymore.

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Crossed the arctic circle today with very nice weather! First catch filled with all 3 species, Blue Whting, Macherel and Herring, second catch dominated by Spring spawning Herring with few mackerel.

This morning Humpback whales were spotted at great distance and dolphins were swimming for a short time in front of the boat, although none of these could be observed by myself…Hope we or I am luckier tomorrow…

For the working progress finally the script to extract catch information and gps positions from the logbook completely works as a vba applet in Excel. Furthermore I finally managed to convert the ctd and logbook data  tables and create a working join in Echoview, so up to now my map includes acoustic SA values with species differentiation from the first day and CTD information of the first day.

Ok small update… we just saw at least 30 Orcas around the boat, an amazing sight…We could even see one big individual swim under the water surface, that’s how close they were…with loads of detections on the sonar and possibly a detection on the echograms…lets see what we manage to do with this data.

Unfortunately now the weather is more clouded then this afternoon and my hopes for a nice midnight sun are drastically shrinking…For the rest I would say everything is up and running. Eric Armstrong got an example file of the noise generated by the sonars so I would guess that there will be a solution rather soon…

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The weather improved over the last two days. Catches are still completely dominated by large mackerel, but night catches more and more contain samples of blue whiting, notable is also the first salmon in the catch. Besides the first cetaceans were spotted, 10 orcas and 1 sperm whale yesterday evening (unfortunately without me being present) and 2 sperm whales this morning, with one nice sighting of a deep dive.

For the rest yesterday I managed to write a script reading catch information directly from the server into excel, splitting it up into the different sheets, so that I can use it for further analysis and representations. The goal is to enhance the script in a way that basic fisheries statistics variables (such as length frequencies, length-weight relationships, sex distribution, maturity stage distribution)   are automatically generated. The first day of accoustic data was scrutinised with limited success, due to quite strong noise disturbances caused by the sonar, using 70 and 110 kHz frequencies, this should be fixed in Tromso on the 26th though, and for the files up to then I will try to come up with an algorithm or use an algorithm developped by collegues on previous cruises.

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The morning shift just started and the next station is going to be in about half an hour. The weather is of rather suboptimal conditions so far today.

I am currently working on my algorith to identify herring, mackereland blue whiting on the echograms from yesterday. Another mission for today is finding a way to visualise CTD information in a good way, showing the profile, especially the thermocline but which could also work as a 3-d map, so normal line are not the preferred option.

This map shows our planned cruise track (LIBAS is the red line), which may vary according to the occurence of the targetted species, we will adopt to nature, not assuming nature is adopting to our predefined track.

The first catch this morning was a big one, about 5 tons of mackerel, 3 Rama rama and 2 horse mackerel.

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After a big rain shower and a rush to the supermarket to get the last bits we could need over the next 2 weeks we were leaving Bergen…Out on the sea until a short stop in Tromso on the the 26th of July…According to the cruise plan we will head nothwest and then north along the Norwegian “coast”, before arriving in Tromso. From here we will head most into the west into Icelandic water and try to find the West spot, so more or less hit the ice of Greenland. In the end the complete survey, in collaboration with 4 other vessels will be covering the whole Norwegian Sea and surrounding waters, an area just approximately as big as the total of Europe.
We will collect ADCP (current), CTD (salinity, temperature, pressure) and accoustic, data as well as fish and zooplankton samples. Fish samples are recorded in an electronic logbook.
The different frequencies of the echosounder and the two sonars were calibrated over the past 2 days.
The first station will be at around 17.00.

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This morning the plane took me to the sunny Bergen (the blue city) and after a few personal complications and a tiredsome shopping afternoon (while LIBAS was getting calibrated) in the city I finally arrived onboard LIBAS. LIBAS is big! Impressed by the size and the equipment onboard. Pictures from onboard will follow very soon, but today I am just a little bit too tired…Tomorrow is another day!

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Two nice shots from yesterday evening…

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This site will soon feature information about what I am doing, where I am and what I am currently working on. For now you can find some information about my current projects and 2 examples of marine data visualisation. An in depth report of my participation oboard LIBAS starting from the 15th of July until the 6th of August will soon begin…

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