こんにちは！M1のMiyaです！
From May 17th to 22nd, I boarded Shinsei Maru together with Shoko and Ren from Yokoyama lab. It was my first time boarding a research vessel, so I was both nervous and excited.
WHERE DID WE GO?
We boarded the ship in Hachinohe in Aomori on May 17th and sailed across the Northwest Pacific Ocean. During the 5 days, we stopped at 16 sites along 4 different latitudes to collect samples. The Pacific Ocean offshore Sanriku region plays a special part in the global ocean circulation. In the surface ocean layer, the Tsugaru current from the Japan Sea joins the cold Oyashio current from the North and meets the warm Kuroshio current from the south. In the deep ocean, you can find the oldest waters of the global ocean, with about 70% originating from the Southern Ocean surrounding Antarctica.
Below is a simple illustration of our voyage route.
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| Ship route of Shinsei Maru KS-22-7 |
Shinsei Maru is a small ship, so it was quite shaky. The first day of work felt quite okay, and then seasickness and sleep deprivation kicked in. About 2 days later, I could survive without seasickness pills. For almost an entire week after coming back to land, I felt super shaky, as if I was still sailing on a ship. Apparently, this means that I have developed my “sea legs”.
WHAT DID WE DO? WATER SAMPLING!
This time, Yokoyama Lab was there to collect water samples for
1. d14C analysis
2. d18O analysis
3. d234U analysis
The water samples were collected by a device called CTD (Conductivity Temperature Depth profiler). A CTD is composed of 12 Niskin bottles, each automatically closes its cap at a predetermined depth and lets the water flows in. There are also multiple sensors on the CTD that gives us real-time data, such as salinity, temperature, and oxygen.
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| CTD rising. This reminds me of flag raising ceremony. |
After sending the CTD into the ocean, it was time to wait. The waiting time ranges from around 20 minutes to 2 hours, depending on how deep underwater we want samples from. When the CTD came back from its deep dive, it was our turn to fill our bottles with the water CTD got us.
Filling water bottles with seawater samples collected by CTD.
The CTD came back! Time to pretreat the samples! |
3 working bees~ From left to right: Ren was sealing the water samples for d18O analysis. I was adding mercury to water samples for d14C analysis to kill the organic stuff. Shoko was filtering water samples for d234U analysis. |
For Uranium analysis samples, we had to filter the water before adding concentrated nitric acid. The filtering system is almost like taking blood. The pulse of the pump felt like the heartbeat of the ocean. When I felt sleepy, I just imagined myself being a doctor, doing a health checkup for the ocean. This woke me up a little bit.
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New knowledge: OCEAN DNA
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| Made with Canva |
In spite of the tight schedule, I had the opportunity to talk with a few chats with some other members on board. Most of the members on board came from the Ocean DNA group since the major research objective of the voyage was to study the salmon migration from Sanriku region to the north. According to my understanding, their goal is to understand baby salmon distribution by analyzing the Ocean DNA in water samples collected from different depths, as well as phytoplankton, the food for baby salmons. Global warming and ocean acidification have huge impacts on the lives below the ocean, and hence generate ripple effects that affect us in return. To better study the health of the ocean, we need to know how the living organisms in the ocean are doing. Ocean DNA contains a wide range of living organisms ranging from bacteria to whales. It is a rather new method that allows us to study the ocean without taking actual living samples. This seems quite fascinating!
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Ocean DNA group collecting surface water. |
PHOTO DUMP
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| Spotted some mariners fishing while the scientists took their samples! I heard that they have these catches as their snacks. |
Time on a research vessel passed real fast. I wonder if it is because we have been working almost non-stop, or is it because happy time always feels fast? Or perhaps, the ocean has some kind of magical power that bends time? Time is relative anyway.
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| Jumping again! |
