The End

Success!

The end of the cruise finally came.  It was quite surreal finding oneself looking at land after staring at open waters for so long.  The day we arrived in Rio was gray and raining, though it is doubtful that it was noticed by many on board.

This was our first sighting of land way off in the distance it almost looks like dark clouds, right around 7:00 in the morning Rio time:

Molly and Alison organized a 'last hurrah' of sorts for the science party and crew the night of the 31st.  It was a way for everyone to say good bye and enjoy their first night back on terra firma.  It was quite a time, and one that few will forget if they still remember.

We finally made it even after everything that happened, and for a cruise lovingly (sometimes) renamed Murphy's Cruise for the frequency of almost catastrophe that followed us, it was an extremely successful cruise.  We were able to complete 120 stations out of the originally projected 124.  Over 2,800 Niskin bottles were fired and sampled from.  10 drifters from the World Drifter Program were released and 15 Argo floats were deployed.  Throughout the voyage 14 different types of samples were drawn to profile the waters in the Southern Atlantic.

There were rough days both physically and metaphorically.  We battled mechanical failures, loss of science party and crew due to time constraints, bad weather, more mechanical failures, homesickness, real sickness, yet more mechanical failures, and the untimely demise of the treadmill.  Yet, we still persevered.  The transect was completed, our sanity remained fairly intact and we all came out of it with a stock of sea tales worthy of any table.

A great thanks goes out to the entire crew of the Ronald Brown.  They kept us fairly lighthearted through most of the adversity we faced and were responsible for getting us up and running.  Without them we would still be sitting in Cape Town.  Thank you guys so much and a big hope that the next time we sail it will be under better winds.

Thanks for reading!
-Elizabeth

Since we have scattered if you want to know anyone's current location send them an e-mail.

Below are a few parting photos: a) A last sunrise, b) Rio,  c) Our grey entrance into Brazil

Day 31 Thursday October 27, 2011

The seas are settling down again after yesterday's trek through a storm system that left a lot of people a little green around the edges.  We were met with a nice sunny day and a few surprise critter visitors, including a sea turtle.

We have started moving north now, as well, along our station track which means Rio is not too far away.  Everyone is getting antsy to see land but work is still going strong.  We have about 14 more stations to go and then a transit to port.

Another group we have on board is Nutrients.  This group looks at the levels of life sustaining nutrients that can be found in the water column.  These are necessary building blocks that are the very start of the aquatic food chain.  These measurements help biologists and chemists measure any shifts of hypoxic regions, as well as expansions and contractions of barren regions in the oceans.  Another purpose for these samples is to measure the Phosphate levels to accompany DIC and DOC processing.  Since as mentioned before there is a known natural ration of Carbon to other elements, including Phospate, this sampling acts as a diagnostic and calibration for Carbon modeling.

Thanks for reading.
-Elizabeth

Our current position is:
28  57.732'S    and   43 15.189'W

Below are a few photos of: a) The sunrise this morning and b) Nutrient's sampling area

Day 29 Tuesday October 25, 2011 10:56 GMT

Both scientists and crew are now getting excited about how close we are to Rio now.  There is a palpable change in the air, a mix of anxious, impatient excitement. 

Work is still going well and fast, in fact we have slowed down a little to give the samplers some time to process the water they have collected before running to take more and becoming backlogged. 

Yet more whales have been sighted and remains quite an amazing spectacle for those who can make it out of labs, or bed to see it.

Another group of scientists on board are our pH and Alkalinity team.

Way back when in our middle/high school/college chemistry classes we learned about the pH scale.  A scale ranging from 0-14 that designates the acidity (or lack thereof) level in a given substance, where 0 was extremely acidic, 14 was an extremely strong base and 7 was fairly neutral.

The pH is measured in the oceans to better study the Ocean Acidification (OA) mentioned in the previous post.  Measuring pH as well as Alkalinity gives two out of four parameters (the other two are DIC and partial CO2) and allows for the calculation of the missing parameters.  The samples collected are analyzed and a specific pH given to each one.  These sample values are then compared to ones taken on previous CLIVAR cruises along the A-10 transect line.  The differences in pH over the years of data gathered give an indication of the change in acidity of the ocean.

Alkalinity is used in much the same way, an indicator in ocean acidity, but is processed differently.  The water samples collected are transferred into closed processing system that prevents the intrusion of air or other particulates into the sample.  Hydrochloric acid is then slowly added until it reaches the same concentration as carbonic acid (Carbon derived acid responsible for ocean acidification and used in studying the carbon cycle).  The amount of acid that needs to be added to the seawater to get this concentration is an important measurement.  The less acid needed, the higher in acidity the sea water is to begin with.

Thanks for reading.
-Elizabeth

We are currently on track to Station 100.  Our position is:
30 0.001'S   and    39 53.74'W

Below are some photos of: a) The pH crew (Valentina and Tammy) -photo by Valentina, b) The Alkalinity crew (Carmen and Jen) -photo by Valentina, c) The view from the bridge

Day 28 Monday October 24, 2011 01:37 GMT

Things are going smoothly.  The winch is working beautifully, the seas are calmer and the countdown until dry land is at 1 week now.  We have just moved through another time zone, we are now at 2 hours ahead of EST and currently on Brasil time.

There have been more whale sightings recently, especially as we moved to the western side of the Rio Grande Rise (located right around 35 deg W).  This rise is similar to the Walvis Ridge, that we passed early on into the cruise, in that it is an aseismic ridge.  An aseismic ridge is a long, linear, mountain chain that is formed by volcanic activity.  An interesting factoid of these ridges is that earthquakes do not occur in these regions.

Continuing with the discussion of the scientific groups sampling we come now to DIC and DOC.

DIC (dissolved inorganic carbon) references the total sum of inorganic carbons such as CO2, carbonic acid, bicarbonate anion, and carbonates.  DIC is linked to the measurements being done to determine the ocean acidification rate.  Ocean Acidification, caused by the absorption of DICs from the atmosphere, contributes to the breakdown of calcium carbonates, a necessary building block for organisms such as coral and shellfish.  For more information on Ocean Acidification see NOAA's site:
http://www.pmel.noaa.gov/co2/story/What+is+Ocean+Acidification%3F
Measurements taken in the ocean are a good way to measure the amount of DIC that is in the atmosphere.  It is hypothesized that one quarter of the DIC in the atmosphere is absorbed by the oceans.

DOC (dissolved organic carbon) is generally derived from the decomposition of organic materials, i.e., plants and animals.  DOC plays an important role in the carbon cycle found in oceans through something called the microbial loop.  This loop is simply a cyclical food chain where DOC is incorporated into a bacterial biomass and then carried through the chain until it returns eventually as DOC.
There is an indication that when high concentrations are found in areas that are typically low in DOC amounts, such as the deep oceans, it is caused by human influence.


Thanks for reading.
-Elizabeth

Our current position is on Station 94 at:
30 0.02 S    and   38 01.00 W


Below are several photos of: a) Location of Rio Grande Rise (located around the 35 W line) and b) Driving along the coast in Cape Town

Day 24 Thursday October 20, 2011 13:43 GMT

Another bumpy day weather-wise here aboard the Brown.  Over the past few days we have hit some high seas and winds.  Nothing too big though, we were still able to deploy and recover the rosette without too much trouble.  We are expecting a rockier ride, though, as we get closer to Brazil.

We have finally hit that countdown point where there are now less than two weeks before we are in Rio.  We just completed Station 76 out of 116 (8 stations needed to be cut due to the delays we incurred from winch issues) and are well on our way to Station 77.  After our deep cast at Station 69 the winch has been much better and casts have gotten faster.  Keeping our fingers crossed that this remains the case.

On that deep cast we sent some more cups down and they look great.  There were only one or two casualties out of the 60 or so that were sent.

Even with the higher seas, a humpback whale was spotted yesterday, though not many got to see it this time.

That's all for now.  Thanks for looking through.
- Elizabeth

We are currently located at:
30 0.001'S   and   29 35.67'W

Below are a couple photos of: a) More sunrise and b) The cups ready to be strapped to the rosette

Day 21 Monday October 17, 2011 13:27 GMT

What started out as a warm, calm day has turned into a fairly gray, cool, wet day.  It doesn't seem to be dampening anyone's spirits though. 

Today was a fairly busy day with multiple long casts and more samples being taken now that we are hitting stations where there is a possibility of North Atlantic Deep Water (NADW) collection. 

NADW is a deep circulation water mass that forms mainly in the Labrador Sea (located between Canada and Greenland).  It is formed of high salinity, dense water that can be tracked as it makes it way from Greenland down the eastern coast of the Americas at depths varying between 2km - 4km (~1 - 2.5 miles) and then east across the South Atlantic towards the tip of South Africa where it mixes with the extremely fresh, cold waters of Antarctica.  The NADW is part of the Atlantic 'conveyor belt' that gets news coverage once in awhile.

That's all for now, thanks for reading.
-Elizabeth

Our current position is:
29 59.99' S   and   23 6.05' W

Below are a few photos of: a) The sunrise this morning and b) A global look at ocean circulation including the NADW - image from: http://forces.si.edu/arctic/02_02_04.html

Day 20 Sunday October 16, 2011 12:41 GMT

There was another amazing sunrise this morning, sadly it did not last too long.
We will be going through another time change later this evening.  Tomorrow we will be 3 hours ahead of EST.

There is progress being made aboard.  The forward winch which we are now using, though slower than we would like, is keeping pace with the new schedule we have in place.  There have been many successful casts made over the last few days and lessening stress levels.

This new system could not have been possible without the enormous amount of hard work being put into it by the crew of the Brown.  There is an increased workload on everyone, including but not limited to the winch operators and second hands to make sure the line spools as well as it can, the survey crew, and all of the engineers.  A big thanks to everyone already for the amount of work they are putting into making this a successful cruise.

Continuing again with a discussion upon the importance of this CLIVAR CO2 Repeat Hydrography cruise, the next group to talk about is Helium and Tritium sampling.  The mention of Helium usually sends people's thoughts running the funny high pitched voices produced from inhaling the gas inside of super market bought balloons. 

In this case Helium takes on a much more serious role.  Helium and Tritium are both tracers much like the CFCs discussed earlier.  They are used to 'age the water'.  Samples taken for Helium are prepared for processing shipboard.  The gas is actually extracted from the water and stored to be sent through a mass spectrometer.  The spectrometer counts the atoms of Helium at each depth.  These amounts are then compared to ratios known for decay rates and the age of the water at those depths can then be determined. 

Why do you need to know the age of water?  Since most of these tracers are introduced at surface level and are consequently mixed down over time to deeper depths, we can determine how long it took the water to sink based upon the age of the tracers in the water.

Tritium is sampled for as well, but those samples are collected and sent back to a lab where they are then prepared and processed.


Thanks for looking through.
-Elizabeth

Our current location is:
29  59.99' S    and    20  46.76'W

*If you want more up to date information on where we are out here in the big, blue South Atlantic visit NOAA's shiptracker:
http://shiptracker.noaa.gov/ship.aspx?ship_code=RBSCSACQ&timeframe=cc&mapservi 


Below are some photos of: a) The sunrise this morning, b) The Helium lab with Anthony Dachille, c) Helium sampling - Photo by Co-Chief Alison and d) CFC sampling - Photo by Co-Chief Alison