Thursday, September 21, 2017

Running South

The aftermath of a wave over the back deck. The float was thankfully still in its
plastic bag. The tape holding the cardboard box closed dissolves after a few
minutes in the water, releasing the float into the ocean (or wherever it is at the time).
We've spent this week in the famous Roaring Forties, named for the westerly winds that are prevalent in this part of the world and often keep the seas high. We left Gough Island (40.3 degrees South) and headed south on what is called 'the buoy run." The weather service onboard the ship deployed drifters that will track currents and weather conditions, and the oceanography team deployed a total of four floats. This included two for the SOCCOM program, floats named Titans and Zora.

The Roaring Forties were true to their name and kept us all rocking and rolling. It's easy enough to adapt when you're walking through a hallway - every once in awhile, a perpendicular step on the wall may be necessary. "Keep one for the ship" means always keep hand free to grab a railing. Less easy is the task of eating in the dining room when everyone's chair is shifting left and right, and the peas on your plate are following suit. The hardest may be to sleep through uneven rolls, a few which threaten to spill you right out of bed. The movement of the curtains on their metal track, the apple in your drawer (don't tell, we're not supposed to have food in our rooms) thumping back and forth with the swell. That being said, I've done alright. Thankfully I can sleep through a lot, and generally sleep better at sea than on shore. But from the grumblings at breakfast and the lack of people socializing in the evenings, I can tell that some of the others have had trouble.

UW technician Rick readied Zora to be boxed up while back
 in Cape Town. The sensor visible at the base of the float
measures chlorophyll fluorescence and backscatter, from
which zooplankton populations can be studied. 
Thankfully the floats were not put off by the weather - both were deployed smoothly and are dutifully at work gathering data. Zora (named for the species of fish people in the video game Legend of Zelda) was deployed at our furthest south station, 47.5 degrees. I was surprised at first to hear that this was the highest latitude some of the scientists onboard have ever been, but then I thought about it and realized it's likely a result of living in the Southern Hemisphere. The only land below 45°S is in Patagonia. Whereas in the Northern Hemisphere, 47.5° runs pretty much along the border between the United States and Canada. All of the UK and half of Europe is above that latitude, as well as most of Russia.

The ship is returning to Gough Island, where there's a few more days of work for the helicopter pilots to do. We did the buoy run ahead of schedule to avoid a storm. Which, considering how high the seas were already, was probably a good idea. It's satisfying to have gotten the work done, and sent the floats off safely. Their work has just begun!

My attempt at drawing a Zora.
Titans, pictured with Cape Town and
Table Mountain in the background.
More on this float in a future post!


Sunday, September 17, 2017

A Float Between Islands

The ship's bosun and his mates stand ready to lower Pixel off the stern of the ship.


Yesterday we deployed another float, our second of the six planned for this cruise. Adopted by Stanford Online High School in California, the float is named Pixel, after the school's mascot.

Pixel was deployed at 06:00 local time, which right now is the same as GMT (Greenwich Mean Time, also referred to as Zulu time). We crossed the zero (also called prime) meridian a few days ago and are now in the West longitudes instead of East. It was still dark out, so not quite as photogenic of an operation as the one from last week, but it went smoothly and that's the important part.

We deployed Pixel during our transit between the islands of Tristan de Cunha and Gough, and it should provide some interesting data. The South Atlantic Subtropical Front crosses through this passage, separating two very different water masses from each other. Oceanographers are able to tell the origin of water throughout the world's ocean using many of the properties collected by these floats, including salinity, pH, nitrate, and dissolved oxygen.

The hope is that Pixel will drift back and forth across the boundary a few times, profiling the water column on each side. It would be great to see plots from this float providing a direct comparison of the tropical-influenced water mass on the north side and the polar-influenced waters on the south.

As I mentioned in a previous post, the scientist studying rockhopper penguins can see the difference in the population that lives on either side of this front as the different water masses support different prey species. She got off on Nightingale Island yesterday, and I will make sure to ask her more questions when the ship picks her up again in a few weeks.

Thankfully Pixel is a simple mascot, so didn't ask too much of my limited artistic skills. 

Pixel is just the latest float to be deployed for the SOCCOM project. Also underway right now is the GO-SHIP P6 cruise, crossing the Southern Pacific Ocean from Sydney, Australia to Valparaiso, Chile. They are also conducting CTD casts and deploying floats, with names like Floaty McFloatface and Magic School Bus. You can follow their blog here.

Wednesday, September 13, 2017

A Day on Tristan da Cunha


Agulhas II off the coast, with the volcano rising in the center, and St. Mary's School (for kids age 3-16) on the right.

The weather was nice today as the ship approached the island of Tristan de Cunha. Passengers were offloaded by helicopter, and then there was time for us scientists to take a trip over as well, being ferried back and forth by the ship's small boat. Tristan is the most remote inhabited island on the planet, 1,500 miles from South Africa and 2,100 miles from Brazil. There's only 260 residents, many of whom are descendant from the same 15 settlers. Even the dogs we saw seem to be from the same family. There's no hotels, but we were able to get our passports stamped and send postcards (which will come back to South Africa on our ship in a few weeks). I recommend reading the Wikipedia entry, it's fascinating. It was quite a treat to get to step on land and see such a unique place. My roommate Caitlin, a scientist studying microplastics, and I walked through town and then out to the lava fields (there was an eruption in 1961) and then to a rocky beach. We saw skuas and albatross by the dozen. I wish we'd had a geologist with us, the rock formations are gorgeous. We had a few hours to explore, and it really did feel like being an explorer as I reckon only a few thousand people have ever been to this place. It was an experience I'll never forget.


Past the lava fields is a rocky beach, with Tristan skuas flying in the breeze.


As we returned to the ship, a Tristan albatross (once thought to be a subspecies of wandering albatross) flew overhead. 

Tuesday, September 12, 2017

Weather Balloons


Weather balloon and instrument package,
with me for scale.
Weather and a few other delays dictated that we put off deploying the next two SOCCOM floats until the return trip. So I've had a few days with nothing much to do, but I'm trying to keep busy by chatting with the other science groups and learning about their projects. 

There's members of the South African Weather Service onboard, some of who will stay on the ship while others get off and work from the islands. Every night, a weather balloon is deployed from the ship - and tonight I went to observe and take pictures.

The balloon is filled with helium on the ship, but on land they're usually filled with hydrogen. A package is attached that measures temperature, dew point (from which humidity can be calculated), and wind speed and direction using a GPS. Last night's balloon went to 21 kilometers before popping. I didn't stay long enough to see how high tonight's went, but I did check out the real-time data plots (see picture below).

From land stations like on Gough Island, a balloon is launched twice a day at roughly the same moment. This global network provides data to forecast weather and track storm movements. It's easy to take for granted that an app on my phone will tell me the forecast, so it's very interesting to see in person how that data gets collected. 
Locations of weather service stations worldwide.
The ascension rate (green), temperature (red), and dew point (cyan) data is plotted in real time.
The calculated humidity (dark blue) spiked likely due to the balloon going through a cloud layer.

Monday, September 11, 2017

Transporting Scientists

Agulhas II will offload scientists and gear
at Tristan, Nightingale, and Gough Islands.
A number of science talks were given today in the ship's auditorium. It turns out that there's multiple field projects on Tristan, Nightingale, and Gough Islands that are being staffed by people on the ship. I'll try to add some figures from the talks, and pictures of the scientists at work if possible.

Antje Steinfurth is on her fourth trip to Tristan Island to study the Northern Rockhopper penguin population, called pinnamins by the locals. 85% of the population breeds on Gough and Tristan Islands. The two islands are 380 kilometers apart (236 miles), but there's a front that crosses through the ocean there that creates a very different environment around each, including a temperature gradient that influences the dominant food source for penguins. I'll see this for myself in the next few days, and we're specifically deploying one of the SOCCOM floats right along that oceanographic boundary. In 2011, an oil spill from a ship that ran aground on Nightingale Island created an environmental disaster and seriously affected the beloved penguins (see more pictures here). Since then, the locals have partnered with government agencies to support scientific studies to monitor the population. Some have been micro-chipped, much like a cat or dog, so that they can be tracked. Antje has set up a scanner that the penguins have to cross in order to get in between the ocean and the nesting grounds. So it counts each individual as they go back and forth.

Subantarctic fur seals live on the islands
by the thousands. 
Greg Hofmeyr of the Port Elizabeth Museum is studying layers of fur seal teeth, which grow like tree rings as they age, in order to determine their diets. The seals breed on Tristan Island, and his team will be aboard for three weeks to collect skulls and teeth from any dead seals they find there. Last year they collected got 90 specimens, so I'm picturing a big bag of them being brought by helicopter when we return to the island next month. Recent specimens will be compared to those in museum collections to determine how changes in the environment has affected their diet over the last 50 years.

There's also a French project called Enviroearth that uses monitoring stations on remote islands to detect nuclear explosions. There are arrays of sensors on the ground that pick up seismic waves and some in the air that can detect even the smallest amount of radioactive isotopes. After the madness of the 20th century, an international treaty in 1995 ended nuclear testing. Since then only six detonations have happened (looking at you North Korea). The scientists are also installing renewable energy in the form of solar panels and heaters on houses on the island.

The South African Weather Service has scientists onboard, a few of who will get off at Gough Island to spend a year taking measurements at the station there. It's been monitored for nearly 60 years and the station is getting old, so one of the technicians is stopping at Tristan Island in order to assess relocating the weather station there. Because of the previously mentioned environmental differences between the islands, this raises questions about data continuity. A few of the weather service employees will stay on the ship for the whole trip. They report weather conditions every three hours, which is used to help the captain make navigation decisions, and the data goes to ground truth climate models based on satellite data. On the run south after we leave Gough Island, they will deploy weather balloons and drifting buoys that will further add to the data set.

So there's a lot going on! This is in addition to the 10 scientists who will get off to spend a year on Gough Island, as well as a married couple who will study land birds on Nightingale Island, completely cut off from the rest of the world for six months. And here I thought I lived remotely for long periods of time in order to do science - all of a sudden this five week cruise doesn't seem like such a sacrifice.

Sunday, September 10, 2017

Marine Mustang begins her mission!

Marine Mustang makes it safely into the ocean.
We deployed our first float on Saturday! Its nicknamed Marine Mustang after being adopted by J.C. Parks Elementary School in Indian Head, Maryland. Deployment went smoothly. Though I usually describe my role in all this as “I chuck floats off the ship and then run analyses to calibrate the sensors,” there is absolutely no ‘chucking’ allowed! Lovingly, gently, carefully it is lowered into the ocean. The sensors and housing may be engineered to withstand freezing temperatures and crushing depths, but a fall could prove fatal. The ship's bosun and his mates did a great job.

It's a little less photogenic this time around since each float is packed up in a cardboard box. This prevents any banging of sensors against the ship during deployment. Tape that holds the box together dissolves after a few minutes, releasing the float. I've heard that this one has checked in, and even gone on its first dive to 2000 meters and reported back with data.



The float before it went in the box. I'm quite pleased with my drawing of a horse actually.




CTD deployment, as seen from two decks up.












The CTD cast came before the float deployment. On the Agulhas II, a giant door along the starboard side opens up and an A-frame lowers the CTD into the water. Once it's back on deck, we deploy the float and then sample the water brought back up from various depths between the surface and 2000 meters.

We have had to delay the second deployment due to bad weather. Since yesterday's blue skies and calm seas, both wind and waves have picked up. We'll deploy the float at that location on our way back, in about four weeks. That's the advantage of a cruise that's going out and back.

Below are a few more pictures. More to come in future posts, thanks for following along!


Bon voyage, Marine Mustang!
J.C. Parks Elementary students learn how to reduce their use of plastic,
which is a huge threat to the health of the world's oceans.





Wednesday, September 6, 2017

Setting up in Port

The floats take in a lovely Table Moutain view.
There's always a loading period before a research cruise where the ship is in port and the science party rushes around getting everything prepared. I've been in Cape Town for a few days now and it's been very busy! I will be analyzing seawater samples for nutrient and dissolved oxygen concentrations onboard, so I have a lot of gear to set up. Thankfully since there's only a few scientists on this cruise, I have plenty of lab space. After making sure all my shipments arrived safe and got onboard, I started unpacking. The lab didn't have power or water the first day, so there was only so much I could do.

By the afternoon of day two, that was up and running so I could test each machine and start making reagents. I had to make a trip to a hardware store to get supplies for securing everything on the lab benches (tables) so it won't fly around if/when we hit some weather. Today (day three) I realized that the power converter I was using for the filtration rig wasn't strong enough and had blown a fuse. Most of our equipment can be used with either 110V (US) or 220V (everywhere else) power, but there's a few things that have to go through a transformer. So I spent a few minutes panicking and then called the chief scientist, who within a matter of minutes had secured me a replacement pump and transformer from a lab at the University of Cape Town. A taxi ride and an hour later, I now have three working pumps instead of zero!

Technician Rick enters the matrix.


I also helped the technician from University of Washington prepare the floats for deployment. He went through a whole series of tests to make sure all the instrumentation wasn't damaged during transport (see photo at right). This involves bringing them out on deck so they can communicate with a satellite, which provided some lovely photo opportunities as well (photo above).
Each float has been adopted by a school, so I wrote the name and drew a few designs on them. We're deploying them in cardboard boxes this time around, so I'll probably decorate those as well.

R/V Agulhas II is quite a ship! It's the biggest I've ever worked aboard, and thankfully has color-coded decks like a parking garage (the lab is on purple fish, or deck 3). There are many differences I've noticed already from the U.S. research vessels that I'm used to - including served meals (rather than cafeteria style) to which men have to wear collared shirts, tea time, a bar (two actually), and the presence of passengers instead of just crew members and scientists. I'll write more about that in an upcoming post. Every ship has its own vibe, and I'm interested to learn more about this one. The South African people I've met so far as friendly and helpful, so that bodes well. Last year I was aboard an Australian research vessel deploying SOCCOM floats and shared that experience in a blog post. 
We leave tomorrow, hope you'll follow along!