Four days hiking in Tromsø – part one

Prologue

I am sitting in the bus number 24, the bus that usually brings me to work.

But not today. It is Saturday, my wife Annika is with me and we will not leave the bus in the center but at the last stop „Kroken“. We have backpacks with us and are about to start a four-day hiking trip through the mountains on Tromsø’s mainland. We leave the bus stop behind, follow the street to the parking place above, pass the graffitis on the “trykkbassenget” and then …

Day 1 – Kroken—Skarvassbu

… we are on the hiking trail. Between the following two photos lie six minutes.

We are following the broad trail slowly gaining altitude and it doesn’t take long till we reach the tree line, which is between 300 and 400 metres in Tromsø. When we look back we can see the northern tipp of the island Tromsøya, but soon the city disappears behind the mountains.

At the lake Krokvatnet the path gets steeper and rockier. We celebrate every cloud because it is a warm summer day with temperatures above 20 °C.

With every hundred metres of altitude the landscape is changing. Soon rocks dominate the landscape, being a perfect habitat for the lichens growing on them.Here we are at an altitude of 700 metres – the highest of our whole trip.

Now we are descending again. Larger lakes have come into view: Čazajávrrit (or Storskarvatnan) and Storskarvatnet. Yes, the Norwegian names are almost alike.+

Between the lakes the cabin Skarvassbu is supposed to be – and there it is. A couple of black-roofed buildings, perhaps a kilometre away. We cross some more boulder fields and then arrive at the cabin. We have a DNT-key with us. That key fits to all but a few cabins of the DNT (the Norwegian Trekking Association), We unlock the door and enter the “hytte”. As many in Norway it is very cozy.

We have pre-booked two beds – probably quite unnecessary, since we will be alone in the night. Since it has been a dry summer the river usually being used to fetch water is dried up completely.

Luckily the small lake nearby has clear water and I fill one of the cabin’s buckets. A bit later I return to the lake to take photos from the cottongrass.

One of the things I love being out in the mountains for several days is watching the changes of light. It still does not get dark but still the sky shows evening colours.

Day 2 – Skarvassbu—Blåkollkoia

When I wake up at 5 o’clock it is broad daylight. It is Sunday, the 4th of August and sunrise was already at 2:45. No reasons for a photo session, I continue sleeping. At 8 o’clock I take some photos with my drone. It’s the first time I have it with me while hiking. Some aerial photos can be pretty boring but the extent of the landscape is often impressive. The mountain in the background is Tromsdalstinden (1238 m).

We have Müsli for breakfast. For milk we mix our milk powder with water. Perhaps not our favourite meal, bit it easy to carry and provides energy for our long trip. Wait, did I write “long”? Today it is only 5–6 km to go.

The first part takes a bit of time because the hiking trail crosses a large boulder field. The marks of red paint – sometimes a dot, sometimes a “T” – are guiding us.

We have left the worst rock fields behind and are looking at a lovely, grassy mountain valley from the escarpment we are standing on. That looks nice! But first we have to follow the winding path that leads down. We pass one of the rare and small snow fields. It has been a warm year and even many higher mountains are free of snow.

And then we reach the alpine meadows that present us a treasure: Blueberries!

According to some tour description Annika found in the net there are rivers to cross. Wading however was not required, all rivers and brooks had very low water levels and were easy to cross and so was the river Goahtevuomieatnu (or Norwegian: Tønsvikelva). We are walking along the river and soon the small cabin Blåkollkoia comes into view where we arrive round noon.

In the afternoon Annika and I go to the river again. We want to check how to cross it the next day, we want to fetch water, we want to clean some clothes and we want to bath. Four times success: There is a bridge, there are nice places to refill our water bottles and to do some cleaning and most important: there is a deeper spot perfect for taking a refreshing bath on an even warmer day. We dry ourselves in the sun and then are sitting by the river for an eternity. This is definitely a highlight of the tour that I will remember for a long time!

And we still have plenty of time. For reading, for taking photos of birds …

… for flying my drone again …

… for preparing dinner (Pancakes with blueberries), for enjoying sun and seeking shadow and for enjoying life.

Note to ourselves: if you want to make pancakes, bring butter or oil …

The next day we will continue to Trollvassbu, with 13+ km it will be the longest day of our four day hiking trip which on the one hand is far, far away from everything and on the other part of the neighbourhood of my work town Tromsø. What a special place in many ways!

 

Visiting the Polarstern

Two days ago the German research icebreaker Polarstern has arrived in Tromsø after a three and a half week cruise in the Fram Strait between Greenland and Svalbard. Today I met the data manager of the Polarstern to learn more about how data is handled on board. Well – I’m deeply impressed! This however is a private blog and no place to talk data.

However I was lucky that the data manager had time to give me a guided tour through the ship. Beside things of professional interest I got to see the mess, the helicopter hangar, a bunk, the operating room, some of the labs, the recreation area with a small swimming pool and much, much more. I took some snapshots that I am allowed to share.

Tomorrow the scientists will arrive and then the next cruise PS144 starts. It is a nine week cruise to the Arctic Ocean crossing the North Pole. (Sounds tempting!)

Today I left the ship after two hours but I’m lucky. On Sunday I will fly to Longyearbyen and next Tuesday I’ll go on board the Norwegian icebreaker Kronprins Haakon to join the two week Fram Strait cruise of the Norwegian Polar Institute. It will be my third cruise and I’m happy and grateful that I’ve got this opportunity.

Today’s thanks go to the data manager – for your time, your explanations and for the “private guided tour”. Vielen Dank!

Four days hiking in Tromsø – part two

It is the morning of 5th of August, the third day of Annika’s and my four day hiking tour in the fjell of Tromsø’s mainland. (Part I)

Day 3 – Blåkollkoia—Trollvassbu

We are at the small and cosy cabin Blåkollkoia and will hike to the next and last cabin Trollvassbu. With round 13 km it is the longest stage, which is actually not so long after all.

The weather is still calm, sunny and pretty warm. We leave round 9 o’clock. The way leads up through sparse birch forests with wet ground. The air is humid and feels hot in the sun. We are sweating and walk quite slowly. After a good km we leave the forested valley behind. Now we have an easy path to walk on over the vidda – the mountain plateau.

But still we are pretty slow. Why? Because of the many berries to pick and to eat. It’s not only the omnipresent blueberries but a lot of multe, Norwegian for cloudberries. They prefer boggy ground with normally zillions of mosquitoes around. This year however the summer was dry and so was most of the ground. Too dry for the mosquitoes. Yeah! I don’t think I ever ate so many cloudberries on a single day as today.

This part of the trail is very easy to hike and it is a pleasure to follow the small path. We really liked it. Some birds – long-tailed-jaegers – however don’t want to have us around. They are flying mock attacks. Soon they realise that we’re just passing and leave us alone. Beautiful birds nevertheless.

We continue walking through the mellow landscape and meet only a single person – a hiker we already met two days before.

The terrain is undulating and the views are constantly changing. So the question is: when will we see the cabin for the first time? Oh – there it is, less than a kilometre away. It lies on an idyllic place by the river Trollvasselva. We are lucky, the river carries water. Most of the smaller streams have been dried out and it was not so easy to find water to drink.

We arrive at the cabin in early afternoon. There are two hikers in the cabin but they do not stay overnight. So we will have the cabin completely for ourselves. We unpack our things, take a snack and wash ourselves in the river. In the evening it is spaghetti time. „Pasta pesto.“

Day 4 – Trollvassbu—Snarbyeidet

Today it is only five kilometres to the bus stop by the road. We have to leave early to catch the bus at 9:55.

I was awake early and took the opportunity to fly my drone. I need some training for the cruise I’ll join next week. Again the vastness of the landscape is impressive. Then we take breakfast, pack our stuff, tidy up and are ready to lock the cabin with the DNT-key.

And off we go. Some hundred metres in open terrain before we enter a dense birch forest that will surround us for the next kilometres. To the right, down in the valley we can hear and sometimes see the river.

The last hundred metres are more open terrain again. There is even a short boardwalk we follow. Minutes (and a bunch of blueberries) later we arrive at the parking place where the busstop is. Time to drop the backpacks and wait for the bus.

At ten o’clock we climb into the bus. We have reliable internet again and are back in civilisation. I’m glad that we did the tour. It is pure luxury to have such tour opportunities right on the doorstep.

Change of subject while sitting in the bus: where is the Polarstern actually? I will visit this German research ice breaker two days later. Oh it already arrived in Grøtsund. And there it is, we can see it from the bus.

Thanks Annika for the wonderful tour. Takk for turen!

I really want to thank the people from the Troms section of the Norwegian Trekking Association (DNT). The cabins are great, in great shape and you all do a fantastic job. Now we are looking to visit the place again in wintertime which according to the guestbooks seems to be the preferred season of many locals.

 

 

 

Before the cruise – Longyearbyen, Svalbard

This article is part of the series “2024-08: Fram Strait cruise KPH”.

Sunday, 11. August

I am sitting in a plane heading north. Tromsø lies behind, the plane goes to Longyearbyen, the largest settlement on Svalbard. If everything goes according to plan I’ll be on board of the Norwegian research icebreaker Kronprins Haakon two days from now to join a scientific cruise to the Fram Strait between Svalbard and Greenland.

Eight other participants are in the same plane, there are not so many flights to Longyearbyen. The rest will arrive tomorrow or has been joining already the previous cruise. We wait for the luggage and then for the “Maxitaxi“ that brings us to our different accommodations. I check in at Gjestehuset 102 and start a photo tour back to the center.

In August the town looks brown. It’s brown water, brown mountains and brown dust everywhere. As a photographer I prefer winter. Longyearbyen lies by the fjord Adventfjorden and there lies the German research icebreaker Polarstern that I visited in Tromsø three days ago.

It is windy but surprisingly warm with temperatures round 19 °C. Later I learn that the maximum was 20.3 °Con this day, the warmest August temperature measurement ever. I stroll around and go to the huge supermarket to buy some goodies. Then I head to the beach again to take some more photos. At 18:30: dinner time with nine of the cruise participants. After that I walk the 2.3 km back to the guesthouse. And take some more photos in the evening light.

Monday, 12. August

Before the cruise many things are on hold. When will the ship arrive? When are the first scientists allowed on board? Is my help needed? When is the flare gun training for the ice people? And so on. Let’s wait and see.

KPH has arrived in the morning but only a few selected scientists were supposed to go on board to get a handover. So I have time to stroll around again – it is still warm and sunny – and take some more photos while constantly checking our WhatsApp group for plans being updated. And I meet some of my colleagues that joined the previous cruise.

In the evening we have another dinner, this time with all 19 participants. That is quite a small team this time, there are 35 berths on the vessel. We have pizza and the first opportunity to get to know each other. What a nice and interesting team I am allowed to work with for the next two and a half weeks :-) !

Tuesday, 13. August

Today is the day. I was already in town and bought a woollen sweater that I wanted to buy for years. Then at 13:00 the first group of people gets a ride to our swimming research platform – Kronprins Haakon. Welcome back. At 13:15 I have boarded, at 15:00 I have checked in. I have got the very same room as on the first cruise two years ago. It’s on deck 3 in the bow and when there is ice, it is shaky, loud and noisy. I love it! Arctic lullabies. This time I have it eben for me alone. That’s luxury!

At 16:00 we get a safety briefing. After that I fetch my safety boots and my survival suit. Will I ever wear it on the ice on this cruise? At 17:00 we have our first dinner. Salmon and rice – delicious. Ice cream as dessert. And at 18:19 I realise that we have left port. Now we will be on our way west.

I will work with a software project and I want to join the sea ice team. The ice situation however is doubtful. Last year there was so much ice, that navigation was a real issue, not its the absence of ice that can lead to problems for the ice people. But as on each cruise – let’s wait and see.

Anyhow I’m lucky and happy to be on tokt – on cruise – again!

I decided not to blog regularly while being on the cruise. There is just too much going on and too much work to do. Anyhow I may show some photos in a few days. Let’s wait and see.

Wind and weather, water and ice

This article is part of the series “2024-08: Fram Strait cruise KPH”.

Wednesday, 21 August 10:36. It’s Annika’s and my fourth wedding anniversary, but I’m far away from her. I’m on the icebreaker Kronprins Haakon in the Fram Strait at 78° 50′ N, 12° 16′ W, that’s between Greenland and Svalbard. Air temperature is +0.2 °C, water temperature -0.1 °C. It is day 9 of the scientific cruise FS2024 of the Norwegian Polar Institute. Today I have found some time to write a blog article and also to publish it thanks to the fast satellite internet on board.

This article is about the journey, about the elements, not about research. I’ll come to this later in other articles.

13 August

Today the 2024 expedition to the Fram Strait begins. Short name: FS2024. 19 participants and 20 crew members are on board. Round 18:00 we leave the port, sail along the Adventfjorden and turn into the 107 km long Isfjorden. When we reach the open sea the sea gets rough and our ship starts to pitch and roll in the waves and not all people feel well. I have a cabin in the bow of deck 3 and the larger waves splash sea water against the port hole.

14 August

In the night the wind has calmed down. We are heading west and it is quite foggy. This year there is much less sea ice in the Fram Strait then usual at this time. Less ice coverage means increased air humidity and that results in fog.

15 August

It continues to be foggy, no need to take any photos of the sea. But in the afternoon the sun manages to fight its way through the fog. This results in two hours with blue sky and also in a phenomenon I never experienced before. A fog bow. As with usual rainbows the sun is in the back so it is not a halo. The water droplets of the fog are so small, that the colours are very weak and so the fog bow looks almost white.

16 August

Research as usual: Two mooring recoveries and several CTD casts, MSS casts, optical casts. The weather: also as usual. It is foggy again and it will stay like this the whole day.

It is not clear whether we will have any ice station on this cruise. The ice stations planned for yesterday and today have already been canceled due to the lack of sea ice and tomorrow it doesn’t look better. At lunch time at least the first chunks of ice have appeared.  That’s a nice change in the uniformness of the foggy weather.

17 August

For days we have been checking the wind speed on windy that forecasted winds up to 40 knots for today. That’s 20 m/s. And the gale has already reached us. The waves have started to get larger with spray on the top. They splash against the few ice floes drifting around us.

In the afternoon all research has been cancelled because of the increasing wind and growing waves. After dinner I go down to deck 3 and into my room. We have average wind speeds of 22-23 m/s now. The ship pitches a lot and in combination with the high waves (I think, 3–4 metres) the port hole of my cabin is occasionally under water. These are some screenshots of a short movie I made with my mobile:

Now the ice floes are not gently drifting anymore but are at the mercy of the waves. Is the storm our friend and blows that one nice looking ice floe in the north towards us? Or will the swell break the ice into smithereens?

18 August

Half past seven – breakfast time. Wind has calmed down to 15 m/s. We are at 78°50′ N und 9°30′ W. I work a lot this day on my computer, hardly looking out of the window. We want to reach 14° W tonight. That’s not so so far away as it sounds, since one degree west means a distance of just 21.5 km at these latitudes.

At 18:30 all people involved in sea ice work meet up. That’s also the people doing “bridge watch” looking for polar bears from the bridge at deck 8. We get a safety briefing for being on the ice and then we see a presentation created by ice expert Henrik that shows the ice situation. There are two possibilities for an ice station for the next day.

It’s hardly believable – we are still in open water with less than 1% ice. But we have a fresh satellite image and people who know ice so I’m optimistic. If only the ice is stable enough.

At least there are some flat ice bergs around.

19 August

At 4 o’clock in the night I wake up. I know this noise, the vibrations, these movements. Kronprins Haakon breaks though the ice! I look through the porthole – we are in the ice! Despite the early hour I get up to take photos on the helicopter deck. It looks so different from the previous days.

Shortly after nine o’clock I take my mobile phone to make this photo:

And this means – after a year and two month I finally stand on the arctic sea ice again. I missed it, I just love this environment! Today’s mission: Flying a drone to produce images for a so-called orthophoto. But that is another story to be told a bit later.

Mooring recovery and deployment

This article is part of the series “2024-08: Fram Strait cruise KPH”.

Yannick using the hydrophoneFor science it is important to get measurements, preferably a lot of measurements. That’s not so easy if you have to take the icebreaker, you have only one and very limited ship time. One thing to go round this is to have sets of instruments that are moored at different locations in the sea. A weight and a buoy keep the communication cable with the instruments vertically and make the mooring stationary

On this cruise we had to recover seven moorings between 78° und 79° N and between 2° and 10° W. To communicate with the mooring a so-called hydrophone is used which can transmit and receive acoustical signals. The hydrophone is used to find the mooring and also to release it. Then the mooring will detach from the weight at the bottom and the upper buoys will slowly drift to the surface.

Then you have to find the mooring . Visually. That’s not an easy task because you will release the mooring in a certain distance to the ship to avoid crashing it into the hull. Beside of that it was pretty foggy this day when a team of NPI engineers and the ship’s crew tried to recover the first mooring with the id F10-19.

But look: There it is! It was found a while ago and our ship Kronprins Haakon is already in position for the recovery.

Now it takes a while to get everything on board without to destroy the scientific instruments. A lot of winch work is involved in the process.

This recovery at 2° W took approximately took one and a half hours. I think that’s quite fast if you consider, that the depth of the sea is round 2650 m at this place. That’s a lot of cable to pull up.

In the afternoon the second mooring recovery took place, this time at 3° W. I’ll show some more photos because this was one of the rare occasions when we actually had sun.

When the mooring was on board the collected data had to be fetched from the instruments and checked while other research was going on in parallel. And so the work continued until the last mooring was recovered three days later.

Of course you want to proceed with the continuous measurements. So on our way back the same amount of moorings had been deployed at the same places. Sometimes a mooring could be re-used, sometimes instruments had to be calibrated on mainland and a replacement was deployed. Each deployment started with the heaviest part, the iron weight that moors the cable to the ground following by the cable, the instruments and some buoys. And then again – a lot of winch work, setting carbines and so on.

Today we got the message: “All moorings are deployed! 🎈” – Great news!

P.S.: One instrument was lost but already in November. The data anyhow is saved elsewhere in the mooring and could be recovered.

Disclaimer: This is a private blog. I try to stick to the facts as good as I can. However this article has not proofread by any other people. Therefore some facts can be slightly inaccurate or even plainly wrong. If you find a mistake, please let me know and I will correct it. Thank you!

Ice station one and polar bears

This article is part of the series “2024-08: Fram Strait cruise KPH”.

For days we wondered, will we ever have an ice station on this Fram Strait cruise in open water? But then at 14° 21′ W, 79° 02′ N we found a large ice floe to work on. Shortly after nine o’clock I finally was on the ice again!

But I wasn’t here to take snapshots but to fly drone and to take a lot of photos from above.

I had issues with the drone from the Polar Institute, so I fetched my private one. First I had to calibrate some sensors, especially the compass and then I put the drone into the air and made some photos to check the image exposure. Ok, looks pretty good.

Now I flew the drone in a rectangular zig-zag pattern. That’s a bit tricky, because the drone is positioned by GPS while the ice flow is drifting. Since I wasn’t sure if I covered every part of the ice station I flew a second round. The single photos look like these:

Before going on board I took a couple of photos on the ice.

On board I uploaded the photos first into my laptop and then into the program OpenDroneMap that would stitch the photos together and add geographical information. And then it was 11:30, lunch time!

After lunch I went up on the bridge on deck 8. Together with two others I was observing my segment checking for polar bears, cracks in the ice and weather. There were several polar bears around but all were further away. I also had a VHF to keep track on the people on the ice. I had two shifts, 12:30–13:15 and 14:00–14:45.

After my second shift I got to know that we had a polar bear in front of the ship. So one of the bears that we had observed for hours had finally decided to pay us a visit. That meant of course that all people had to leave the ice.  On the helicopter deck many people were around to watch the bear.

And there it was – a surprisingly white curious fellow that examined our ship. Did it smell the cake?

In the meanwhile OpenDroneMap finally created a properly rendered orthophoto. I was relieved because I was not sure if my drone photos were sufficient. This is an excerpt:

In the afternoon I had fixed the issue with the other drone. At 19:00 I would have another opportunity to go onto the ice to re-calibrate and test it. Our ice visit was however postponed because another polar bear was paying a visit. It looked much thinner than the other one, but on the other side the fur was wet. So photo shooting again. It surrounded the ship and then stopped, laid down onto its stomach, pushed itself forward with its furry feet and  then rolled in the snow before it continued its walk.

We had to wait some time but then the ice was clear and I had time to test the drone on the ice. It worked. Hopefully I would be able to use it on the second ice station on the next day but the forecast does not look promising. Too much wind.

I shot a drone selfie and then I was ready to go on board. I just had to put my hand into one of the polar bear paw prints for size comparison.

The bear won!

Ice station two and icebergs

This article is part of the series “2024-08: Fram Strait cruise KPH”.

When I woke up in the morning of the 20th of August my first thought was: will there be another ice station? I peeked through the port hole and – yes – we were at least in the ice. From the helicopter deck it looked like this:

Round nine o’clock the ice station is started. Eleven people are involved – four scientists and students actually doing science, a polar bear guard on the ice and two times three bridge watches taking turns to observe everything from above. I take the morning shifts, the weather is not good for drone flying anyhow. Yesterday we had a lot of polar bears on the ice, today it is quiet. It is more the fog that could lead to problems, but even the visibility is ok. Good luck.

In the afternoon it has become too windy to fly the drone. I get onto the ice anyhow to take photos for outreach. Time to show people doing research on the ice. It is a lot of manual work. Carrying things down the gangway, pulling sledges, using drills with coring equipment, a saw to slice the ice cores, a digital thermometer and for a lot of data – paper and pencil. This may sound antiquated but writing down notes works often works better in harsh environments than using electronics.

Later, just before dinner people who never have stood on the sea ice before become an opportunity to do that. I was on the sea ice three times since yesterday, so I volunteer for bridge watch again. The weather has become more and more nasty. It is raining and wind is blowing with temperatures round +1 °C. So it looks from the bridge:

At 17:30 (dinner time) the second ice station is finished. Now we will head back more or less the same way we came from. I take some photos from the helicopter deck, especially from the turquoise coloured melt ponds that I have never seen before like that.

At 9 o’clock we reach the ice edge and sail through the open sea again. Time to say farewell. I do not know when I’ll may see my beloved sea ice again.

Anyhow one thing was different than on our way there some days ago: icebergs are drifting on the sea. We see a lot of them on this and the following day. Some of them are small or medium sized …

… one of them was huge. I am able to take a drone photo from above. I estimate that the cliff to the right has a height of 10-15 metres.

There was one difference between the two ice stations. It is visible on the map:

While the 2nd ice station started and ended at the same place, the 1st ice station didn’t. This is because the 1st station was on drift ice while the 2nd station was on fast ice. Fast ice is either grounded or it is connected to land, in this case Greenland.

Although Greenland with islands was more than 50 km away it was visible on the 19th of August. I was really surprised and also happy – I have never seen Greenland before. And I managed to take some blurred photos (cropped image, 600 mm focal length).

Feels like I should visit that place sometimes …

Hydrographical measurements in the Fram Strait

This article is part of the series “2024-08: Fram Strait cruise KPH”.

You see the map with Greenland to the left and Svalbard to the right? And all these orange dots?

Each of the dots stands for a cast where an instrument or a set of instruments was lowered into the water. As you see it was quite a lot of casts that the researchers and the crew of the icebreaker Kronprins Haakon conducted in the Fram Strait between 14° W and 10° E within two weeks.

Let’s start with the most prominent hydrographical instrument, the CTD.

CTD stands for Conductivity, Temperature, and Depth. It is a group of instruments to measure these important water properties. The conductivity is directly related to salinity. While the CTD is lowered these three properties are measured continuously which results in so-called “profiles” that show the salinity and the temperature per depth. With these properties oceanographers get the first insight in what kind of sea water it may be. It is Atlantic? Or Arctic? But there are also other sensors mounted to the CTD to measure properties such as fluorescence or current velocities.

Also part of a CTD is the rosette of “Niskin bottles”. These bottles can be opened and closed remotely underwater to fetch sea water in defined depths on the way up. The large CTD has 24 of these bottles. When it is on board again and stands on the euro-pallet in the main hangar on deck 3 then it is time to fetch water samples from the Niskin bottles.

Some of the samples will be processed on land after the cruise but many samples are processed directly. Two examples:

Anne-Marie Wefing (NPI) uses the Winkler titration to measure the concentration of dissolved oxygen in the sea water. My chemical knowledge is too weak to explain this process. For the chemists amongst you I refer to the Wikipedia article for details.

Daniel Koestner (University of Bergen) leads water through different types of filters. The water can pass, particles exceeding a certain size will remain in the filter. While the deeper sea water is quite pure the samples from the upper water column contain more particles. The difference is visible by the naked eye but only land-bound lab work will give quantifiable results. Some of the filters can be transported at room temperature, those for chlorophyll have been frozen at -80 °C.

Daniel Koestner is also part of the team that measures particle concentrations directly in the water using a laser. This is how the instrument of the “optical cast” looks like:

The CTD is a heavy-duty instrument and could be used more or less all the time. Other instruments such as the laser or the MSS are much more fragile and the usage had to be skipped when the waves were to high. Too big the risk, that an expensive instrument would crash. But as far as I know everything has gone well!

Some cruise stats:

CTD casts 73
Optical casts 44
MSS casts 27
Total casts 144

While I have the luxury to work whenever I want the sheer amount of casts has led to a huge amount of lab work and some teams have been working in shifts, because casts have been conducted day and night.

Disclaimer: This is a private blog. I try to stick to the facts as best as I can. However, this article has not been proofread by anyone, so some facts may be slightly inaccurate or even plainly wrong. If you find an error, please let me know and I will correct it. Thank you!