Home again.

34°27S 150°52E
11:48AM

Hi all,

I’m now back home in Wollongong, back studying at the university.

The ship returned to Hobart on Sunday the 5th of March. We had a couple of busy days of demobilisation, then some (hopefully temporary!) goodbyes before we went our separate ways.

Some of the gang!

Reflecting on the voyage, I feel exceedingly grateful to have been on board. It was inspiring to see firsthand how exciting and relevant science happens in the challenging and isolated work environment of the Southern Ocean.

It was great to learn about science outside my discipline and meet so many people motivated to better understand our world. I’m sure some of them will be my friends for a very long time.

Heavy weather on the way home.

I need therefore to say thanks again: to CSIRO Oceans and Atmosphere, in particular Ruhi Humphries, the Centre for Atmospheric Chemistry at UOW, the MNF and all on board the Investigator.

Thank you all for reading and following my adventure!

Cheers,
Jack

Rough seas

01/03/2017 14:40 EAST

54°28S  135°36E

Hello again from the middle of the Southern Ocean.

We are currently in the early stages of what’s forecast to be a pretty solid storm. Life at sea conjures up images of a moving a vessel, so I thought I’d share some of the unique parts of living on a moving vessel.

Showering one handed is very difficult! When the ship is rocking and rolling, it’s necessary to hold on at all times to avoid a trip to the little hospital on 02 Deck. This makes it hard to wash your hair and clean under your arms- water also goes all over the floor!

Cups and plates also slide around very easily: Meghan discovered this the other day when she left a coffee unattended for a second, and before she knew it she had a slightly caffeinated sleeve. To this end, it is very important to tie down everything that can move on board. This includes equipment in the lab as well as personal items.

Another thing is the noise. There are endless creaks and groans, and the occasional boom and shudder as the bow of the ship plunges into a wave trough.

At the present moment, winds are blowing at 30kn, it’s raining, and air pressure is 989hPa and dropping. Something tells me it’s going to get worse before it gets better!

 

Instrument of the Day

The nephelometer is a permanent instrument here on board the Investigator. It measures light scattering caused by aerosols in the atmosphere. When certain wavelengths of light hit particles with a particular size, it can be scattered (deflected off it’s original path).

The nepheolometer measures this deflection at angles from 0° through to 90° at 5° increments. Lasers at three wavelengths provide the light source.

 

Thanks for reading!

Jack

(Apologies for the lack of photo: we are having some issues with communications down here)

The Engine Room

23/02/17 02:45EAST
65°06S 118°50E

The Engine Room

Genna is from the Ukraine. He has 30 years experience at sea, and holds a very impressive title: chief engineer of Investigator for this voyage. The engine room is a part of the ship off limits to us most of the time. However Genna takes pride is showing off his work so takes a couple of engine room tours each voyage. I joined him yesterday.

We first visited the emergency generator. This automatically switches on to provide emergency power to the necessary places in eleven seconds, should the main generator fail. It can run independently for three days and requires no cooling.

We then went down to look at the propeller shafts. Two main propellers drive the ship. They are specially designed to move quietly through the water and are made of a Cu:Ni alloy, with a diameter of 2.9m. Two rudders behind the props steer the shift. They are controlled from the bridge, but can be controlled manually from the head of the rudder in the engine room should the system to the bridge fail.

The top of the port rudder, which steers the ship.

There are 14 winches on board, used for a variety of tasks. There is a winch to lift on board the supplies for the galley and large instruments, winches for putting down corers, winches for the plankton net and for the water-sampling rosette. The winch room is where many of them are kept, including the long core winch. The cable on this winch has is made of a pre-stretched polymer material, making it very light and limiting stretching. The cable is seven kilometres long, for coring deep seafloor.

The synthetic long core winch cable, all seven kilometres of it.

 

The main engine room was noisy, but not as noisy as you would expect! Three main diesel electric generators power the ship. This ensures the ship burns cleaner than other vessels, which burn crude oil.

It was very interesting to go down into the depths of this ship and see the complex system that provides our fresh water, energy and propulsion.

Instrument of the Day
The PM (Particulate Matter) 1 filter system on board is designed to capture all atmospheric particles greater than one nanometre in diameter. This pore size captures everything considered an aerosol., which can be taken back to a lab ashore for further analysis. The filter system consists of a pump, a flow meter, and the filter cartridge, in which the filter is changed every 24 hours. The pump is on a switch that automatically cuts off when the air sampling inlet is pointed towards the ship’s exhaust.

Thanks for reading,

Jack

 

A whale of a time.

16/2/17 0511 EAST
65°07S 120°22E

In Wollongong, twice a year we are lucky enough to see the migration of humpback whales north and south off our beaches. Last spring I saw an especially large number of whales: almost every morning while down at the beach I would spy a puff of spray or a dorsal fin.

Down here, however, whale activity is on another scale! As my biological peers tell me, the whales are feeding on krill. Krill in turn feed on the massive phytoplankton blooms that occur in the Southern Ocean each summer. The upwelling of nutrient rich deep ocean water, and the abundance of incoming solar radiation present in this part of the world during the short summer trigger these blooms.

On calm days, especially when the boat is stationary (while a core is being taken for example), it seems the ship is a whale magnet. The other day we had about five friendly humpbacks come to investigate the Investigator, and swim two full laps around the ship! The ‘whoosh’ of the blows apparently made the deck crew jump. It is very cool to be able to truly get a perspective on the size of these creatures (especially considering the tiny creatures on which they feed!).

Sadly, I’ve not detected any whale blows in my aerosol measurements.

Instrument of the Day:
The Aerosol Chemical Speciation Monitor (ACSM) reveals the chemical makeup of measured aerosol. While the other instruments described previously focussed on counting aerosols and telling us how big they are, the ACSM can tell us what they made of. Some possibilities in this part of the world are sea salt aerosols, emitted directly by wind and wave action, or sulphate aerosols, produced via chemical reactions with a by-product of phytoplankton photosynthesis. It works using mass spectrometry, a widely used chemical technique in which molecules are fragmented into ions, of which a mass-to-charge ratio can be measured.
Molecules form characteristic ion fragments, which allows for reconstruction of the parent compound.

Jack

A new cetacean pal waves hello.

A trio of humpbacks. Deck crew for scale.

 

The core of it all

14/02/17 02:27 EAST
64°32’S 117°26’E

As I’ve mentioned previously, the main objective of this voyage is not aerosol chemistry. Rather it focuses on the past climate of the East Antarctic region by mapping the sea floor surface, examining sub-seafloor sediment layers, and taking water samples and sediment cores.

The last of these processes is amazing. The depths of water in which we core often exceed 3000 m! A barrel goes down on a (very long) winch, and is speared into the sediment. There are three different coring processes, aimed at different parts of the sediment, in use on this voyage of the Investigator.

The Kasten core has a square barrel that can be opened on board. This means extensive core descriptions can be undertaken, and samples taken and processed for further analysis ashore. It normally has a three-metre barrel. The multicorer is a rosette of six identical core barrels, each one metre long. This device is designed to land gently on the sea floor, and provides an excellent record of the sea floor surface. Finally, there is the piston core. This is by far the longest coring system in use on the voyage. The core barrel has been deployed at 18 metres, with a whopping 16 metres of sediment retrieved. The piston cores are cut into more convenient one-metre chunks and are kept closed. They are run through the GeoTek logger, which provides some properties such as magnetic susceptibility and resistivity.

So what is so interesting about this sediment? Seeing the cores and the variation between them has let me begin to appreciate what many of the other scientists on board are so excited about. The sediment mostly consists of fine clay material, fossilised plankton, and occasionally layers of sandy grains. The composition of the sediment and species of plankton observed under the microscope can provide clues as to what environmental factors were effecting sediment deposition as we go down the core. This provides a very useful proxy for paleoclimate (the climate of the earth in the geological past). Hopefully by examining past trends we will be able to take a better guess at the behaviour of the Totten glacier in warmer periods of the earths history, and make some predictions about the future. Not bad for a bunch of mud if you ask me!

Instrument of the Day:
The Scanning Mobility Particle Sizer (SMPS) is an instrument that provides a size distribution of the aerosol in the local atmosphere. As the air enters the instrument, it enters a radioactive chamber which ionises (gives a charge to) the aerosol population. The newly charged particles then travel into a column across which voltage is applied. How the particle reacts to the applied voltage depends on its size-to-charge ratio. Since we know the charge on the particles, we can easily select the size of the particle by changing the voltage in the column. The column therefore takes an aerosol population with many different aerosol sizes, and selects just one size, which is fed into a simple particle counting instrument (see my post from January 28th) giving a particle concentration for a given size. As we ramp through the voltages, we change the size being counted, and in a few minutes, we get a full size distribution (an histogram if you will). The size distribution obtained can give us clues to what kind of aerosols we are seeing in our sample and what interactions they are having with their environment.

Sarah examining the archive section of a kasten core up close. It’s wrapped in plastic to assist with preservation. The rest of the core has been sampled for further analysis such as fossil counts and x-ray diffraction.

 

 

Sunshine on my window makes me happy

10/02/17 08:48 EAST
64°49S 119°12E

Since we left Hobart, I can recall it being sunny for about 5 hours. That’s not much sunshine for about 25 days at sea. I thought it wasn’t really affecting me, I didn’t feel down when I got up in the morning and saw grey clouds and grey sea.

But yesterday, the sun came out properly, and stayed out for more than a few minutes. I finished my shift a little after two and wandered outside on 02 Deck. Seated against the wall on the port side, facing the sun, was a collection of about ten of my fellow scientists, all very much enjoying the light and warmth. I joined them, and was soon warm enough to sit in just a t-shirt. This might not sound very exciting to those of you in the baking Australian summer, but down here its rare to go out without at least four layers. It was a very pleasant way to finish the day, sitting out there chatting.

Coming back inside, I felt like jumping for joy. Though I hadn’t realised it, I had missed the sun, and very buoyed to see it for a couple of hours! I also like seeing the sun for another reason…

Instrument of the Day
MicroTops is a portable sun photometer. It measures what wavelengths of radiation from the sun has been scattered out and absorbed as it travels through the atmosphere. I aim it at the sun and take measurements. However, to collect reasonable data I need to be able to see the entire solar disk (with no cloud cover of any kind). For that reason, I haven’t been able to take as many measurements as I would have liked with the MicroTops to date!

Cheers,
Jack

Liam, my cabin mate, helping me out by taking a sun photometry measurement in a rare moment of sunshine

Getting up at 0200 means (very occasionally) a beautiful sunrise.

 

A real process.

06/02/2017 05:27 EAST
64°40S 119°18E

Now you know a little bit about some of the instruments in the lab, you might wonder what happens to all the data they put out. As the instruments are running continuously and measure at short intervals, there are many points created over the course of an hour, let alone the whole voyage.

All the computers on which the instruments are running are connected to the ship’s network. The helpful people in Data Acquisition and Processing (DAPs, the ships IT gurus) have set it up so that when a data file is saved on the instrument PC, at specific times of the day it is backed up on the ship’s server system. The ship server is replicated multiple times throughout the vessel, providing multiple layers of data security.

As well as providing a backup system, this means I am able to access data from my own computer. This is very helpful: it allows me to work on data processing from wherever I please on board.

During the voyage, I have begun learning how to process data using the computer programming language ‘python.’ Karl, the DAPs staff on my shift, has assisted greatly with this. Ruhi, my supervisor from CSIRO, has also provided me with some scripts he wrote to process similar data.

It is like designing a small piece of software: you tell your code where to find the data, what parts are important and any processing you need it to do. Hopefully at the end you can end up with a data product such as a voyage time series or diurnal plot that is much more user friendly than the list of numbers produced initially by the instrument. I’ve managed to make a few rough initial graphs of the data I’m collecting, but still have a long way to go!

Instrument of the Day
Today’s instrument is the Tekran Ambient Mercury Vapour Analyser. This instrument measures gaseous mercury in its elemental phase. It works by first collecting the mercury from the air on a gold cartridge. The mercury is then taken off the cartridge by heating, and measured via a
mercury lamp emitting a specific wavelength of light that mercury absorbs. The instrument calculates mercury concentrations in units of nanograms per cubic metre!

¡Hasta luego!
Jack

Raw data showing cloud condensation nuclei (CCN) counts (number of CCN per mL). Each hour the instrument goes through a cycle of supersaturations, starting at 1% and decreasing to just 0.3% (i.e. 101% and 100.03% relative humidity). The higher supersaturations result in more of the aerosol population being able to grow to detectable sizes. The large spike just before 4pm UTC is when I was doing my daily checks and the instrument was measuring lab air for a short period. Just after these checks, we experienced a big snowstorm which scavenged lots of the particles, resulting in very low concentrations compared to earlier in the day.

Sarah and Adrián hard at work, possibly looking at data stored on the ship server.

ShipMATES.

02/02/2017 03:36 EAST
64°44S 118°20E

Before getting on board, I was a little apprehensive about the voyage.
Being unfamiliar with being at sea and the instruments I would be working with was one thing, but a main concern was the social aspect of the journey. Seven weeks is a long time to spend with people you have never met. Seven weeks on a relatively small ship (with no escape!) could feel like forever! I needn’t have worried.

Upon leaving Hobart, and especially since starting shift work, my fellow scientists and I have become firm friends. Our shift represents a cross section of the scientific community, encompassing undergraduate students, PhD students, post-docs and established professors. This creates a wonderful learning environment for the other students and me.

We are often treated to pearls of science wisdom from our seniors, which are much appreciated. I hope this relationship goes both ways, and that our youthful vigour is enough to keep everybody excited and motivated.

While the 2am-2pm shift is a great scientific environment, it is also great fun. I have no problem finding volunteers to come to the aerosol lab with me (a number of mates have commented that they find the instrument humming very peaceful!), in return for a hand with core processing or water filtration. We laugh often and all get along well which makes sometimes arduous tasks, such as sieving kilograms of mud, much more bearable.

A frequent source of mirth originates in idioms lost in translation (Adrián is a Spanish PhD student and Amaranta Italian); or in different pronunciations between English speaking nations (Meghan and Amy are here from New York state).

I’m very grateful for the company of all the wonderful people that I am working with on the ship. I know I’ll have someone to laugh with and someone to talk with whenever I need (which is comforting in this amazing but sometimes strange part of the world!).

Instrument of the day: Cloud Condensation Nuclei Counter

This machine measures aerosols that are hydrophilic (water-loving). This type of aerosol is crucial for cloud formation, and impact cloud properties such as lifetime and precipitation patterns – hence they are known as Cloud Condensation Nuclei, or CCN.

It works very similarly to the UCPC I described in my previous post, but instead of using butanol, we pass the sample air through a chamber supersaturated with water. As water condensed onto the particles, the aerosols grow to a size detectable by laser. The type of CCN affects how quickly the particle grows, and the instruments measures this by outputting both a particle count and a size distribution.

Thanks for tuning in!
Jack.

Adrián and Meghan measuring the magnetic susceptibility of a sediment core

The lab.

28/01/2017
64° 28S 115° 27E

Measuring aerosols is a little logistically tricky. They have a frustrating tendency to stick to inlet lines if they have to travel any great distance. To counter this, the aerosol sampling lab on board the Investigator is right at the bow of the ship. The Investigators website has a virtual tour of the ship, the aerosol lab can be found on the Foscle. It is situated directly beneath the mast, where the air sampling inlet is located. This minimises the distance samples have to travel before being measured by instruments in the lab.

This location provides an interesting work environment. The lab is essentially fully enclosed within the ship’s hull. There are no windows!
This lab, different to most others I have worked in, also tends to move around. Being at the very bow, when the ship is pitching and rolling, the aerosol lab is an exciting (or terrible, depending on the quality of your sea legs) place to be.

Accessing the lab requires crossing the foscle deck. This is where the anchor chains and mooring lines are stored. It is partially open to the air, via a series of portholes. Looking out these portholes makes you feel as close to the ocean as anywhere on the ship. At night, the inky blackness provides a reminder of how far we are from other artificial lights. During the day, depending on the mood of the sea, it is either a beautiful or humbling reminder of the scale of the ocean.

So getting to the lab is exciting! But ‘what is in there?’ you may ask.
For the next few posts, I’ll describe an ‘instrument of the day’ to give you an idea of how it all works.

Today: the Ultrafine Condensation Particle Counter (UCPC)

The UCPC is an instrument designed to count particles of diameter 3 nm (that’s a billionth of a metre!) and greater. It works by passing sample air through a chamber supersaturated with butanol (a type of alcohol), which condenses onto the aerosol particles being sampled (hence the “condensation particle” in the instrument name).
This grows the particles sizes larger than a micron (a thin human hair is 20 microns) where they can be detected by a laser, giving a count of particles over time. Measurements are taken at 10 Hz (10 times per second) then averaged over each second.

Thanks for reading!
Jack

Who needs weekends?

22/01/2017
64°13S 117°43E

You may wonder how those aboard the Investigator fill our days. Surely one can only steel their gaze to the horizon so many times? Below is what my day will look like today. Nearly everyone on board is on shift, crew and scientists. We work the same hours seven days a week, which makes it hard to keep track of which day it is!

0130 Get up and have a cup of tea.
0200 Start shift, go to aerosol lab and do instrument checks (see photo!).
0330 Computer work (trying to get some data into plots, check data backups), help do some microscope work looking at plankton from seawater samples, learn about sedimentary core descriptions from my friend Adrian (in preparation for when we get them on board for analysis).

0700 “Breakfast” (aka lunch).
0800 Change filters and check instruments in the air chemistry lab.
0830 Watch for whales with Vanessa, the marine mammal observer on board.
0930 Back to the lab to address any issues, more microscopy or computer work, go outside and look at icebergs.
1030 Log ship position, seawater temperature, speed and other variables.
1200 “Lunch” (aka dinner).
1300 More lab time or computer work.
1400 Finish shift, scientists meeting.
1430 Go do exercise and wander round outside.
1530 Play cards or read.
1700 ‘Dinner’ (little bowl of soup or something)
1800 Bedtime.

There you have it!
Jack

A panorama perspective of the aerosol lab showing some of the instrumentation being used for continuous atmospheric sampling.