Catherine Fuller: Into the Copper River Plume, July 7, 2019

NOAA Teacher at Sea

Catherine Fuller

Aboard R/V Sikuliaq

June 28 – July 18, 2019

Mission: Northern Gulf of Alaska (NGA) Long-Term Ecological Research (LTER)

Geographic Area of Cruise: Northern Gulf of Alaska

Date: July 7, 2019

Weather Data from the Bridge

Latitude: 59° 40.065 N
Longitude: 146° 04.523 W
Wave Height: 2-3 ft
Wind Speed: 10.4 knots
Wind Direction: 254 degrees
Visibility:  100 m
Air Temperature: 12.0 °C
Barometric Pressure: 1015.4 mb
Sky: Overcast, foggy


Science and Technology Log

Usually LTER cruises are more focused on monitoring the ecosystem, but in our case, the cruise will also focus on a process study of the Copper River plume.

Copper River plume
This is a satellite photo of the plume with an overlay of the salinity of the water along our course. The darker colors represent the lowest salinity.

This seasonal plume brings iron and fresh water into the marine ecosystem, where they are dispersed by weather and currents. Because our winds have been very light, the plume is retaining its coiled shape remarkably well.  Our sampling on the Middleton Line (prior to the plume study) will add information about how both the Copper River fresh water and iron are spread along the shelf and throughout the food web.  

Clay Mazur
Clay checking the fluorescence of a sample.

Clay Mazur has a particular interest in the iron-rich waters of the plume.  He is a graduate student from Western Washington University who is working under Dr. Suzanne Strom (also onboard). He is one of a few on board who are working on their own experiments as opposed to assisting others.  The overall goal of his work is to study how iron in phytoplankton is limited and how the sporadic addition of it can stimulate growth.  He has a gigantic on-deck incubation experiment in which he will take an iron-limited plankton community from offshore in the Gulf and introduce iron-rich water from the Copper River plume to see what happens.  Clay will measure chlorophyll – an indication of biomass – by which he can estimate the plankton population.  He will also be checking the physiology of plankton in different size classes, and taking samples to see the pigments that every cell produces and if they change over time with the addition of water from the Copper River plume. His hypothesis is that everything should change: phytoplankton species composition, cell size, photosynthetic ‘health’, and chlorophyll production. When phytoplankton are iron-limited, they cannot produce healthy photosynthetic structures. 

Clay measured the same indicators on every station of the MID (Middleton Island) line and will also measure the same on GAK line.  These samples will use the metrics described above to show environmental heterogeneity along the cross-shelf sampling lines. Samples from the MID and GAK line will also allow his iron experiment to be seen in context.  Does the iron-rich community that develops during the experiment match anything that we see on the shelf? How realistic is experiment within the Gulf of Alaska? Clay would also expect a diatom bloom with the introduction of iron into his sample population, but he says there are not a lot of cells greater than 20 microns out here and 5 days may not be enough for diatoms to grow up from this small seed population.

The Acrobat

One specialized instrument being deployed to gather information about the Copper River plume is the Acrobat.  Where the CTD is critical to give a site-specific profile of various indicators in the water column, the Acrobat can provide much of the same information along the path of the research ship, such as through the plume or across the shelf from deep regions to shallow.

CTD Screen
This is an example of the readout that comes from the CTD when it is deployed.

Lead scientist Dr. Seth Danielson from UAF, and Pete Shipton, a mooring technician from UAF’s Seward Marine Center are using the Acrobat to record a number of parameters as it moves through the water column.  The Acrobat is lowered off the stern of the ship and towed behind us.

Acrobat on deck
Bern, the Marine Tech, and Paul, the Bosun, with the Acrobat on deck prior to launch

As it is towed, it dives and climbs in a repeated vertical zigzag pattern to sample the water column vertically along the length of our course, creating a “cross-section” of the ocean along our line.  The Acrobat measures water temperature, salinity, density, chlorophyll, particle concentrations and CDOM (colored dissolved organic matter). The CDOM indicator allows the Acrobat to distinguish between different water colorations.

The path of the Acrobat can be constrained by distance from the surface or seafloor, in which case it receives depth sounder readings from the ship itself to inform its “flight” behavior.  It can also be set to run a path of a set distance vertically, for example, within a 20m variation in depth.  When set to a maximum depth of 40 m, it can be towed at 7-8 kts, but someone must always be monitoring the “flight” of the Acrobat in relation to ship speed to ensure the best possible results. The operator provides a watchful eye for shallow regions and keeps an eye on the incoming data feed.  The Acrobat also has two sets of wings.  The larger set will allow the Acrobat to reach a maximum depth of 100m or carry a larger sensor payload.  The profile being created as we tow through strands of the plume indicates that there is a pronounced layer of fresh water at the surface.  A concentration of phytoplankton, indicated by high chlorophyll a fluorescence levels, lies just beneath the fresh water layer and as we exit the plume, we observe a subtle shift towards the surface.  The fresh water also contains a good deal of sediment from the river that settles to the bottom as the plume spreads out. As we cross through the plume, we see the sediment levels at the surface drop, while the temperature, salinity and density remain fairly constant, showing a continued flow of fresh water at the surface. 

The readout from the Acrobat appears as a series of bar graphs that record in real time and provide a clear picture of what’s happening in the water column as we move.

Acrobat screen
This is what the Acrobat readout looked like as we went through a portion of the plume.

Once the data from the Acrobat is gathered, Dr. Danielson is able to create three-dimensional representations of the water column along our path according to the individual indicators. One that is particularly interesting and important for the Gulf of Alaska is salinity, which exerts strong control on water column stratification and therefore the supply of nutrients into the ecosystem.

Acrobat salinity graph
Here is a 3-D representation of the salinity along our plume route.

The low-salinity waters of the Gulf of Alaska are influenced by the fresh water precipitation, snow melt and glacier melt in the coastal Alaska watershed, including the big rivers like the Copper River and the thousands of un-gauged small streams.  Some of the fresh water runoff eventually flows into the Bering Sea, the Arctic and the Atlantic Ocean, playing its role in the global hydrological cycle and the conveyor belt that circulates water through the world’s oceans.  Oceanographic monitoring has shown that the Gulf of Alaska water column is warming throughout and getting fresher at the surface, a consequence in part of glaciers melting along the rim of the Gulf of Alaska.


Personal Log

Finding my way around onboard was initially somewhat confusing.  I would exit the main lab and turn the wrong way to locate the stairway back up to my room, and it took a few days to figure it out.  Here’s an idea of the path I take in the mornings to get from my room to the lab:

Here’s what our stateroom looks like…yes, it’s kind of messy!

One rule when you open a door, because the hallways are narrow and the doors are heavy, is to open slowly and check for people.

The stairs are steep with narrow treads and necessitate careful and constant use of the handrails.

From the main hall, I usually go into the wet lab.

From the wet lab I can either go into the main lab…

Main lab
Main lab

… or into the Baltic Room.

Baltic Room
Baltic Room

There are six levels to the ship.  At the bottom are supply rooms, equipment, the engine room, workrooms and the gym.  On the main floor are the labs, workrooms, laundry areas and computer center.  On the first floor are science team quarters, a control room for the main deck winches, the mess hall and a lounge.  On the second floor are crew quarters.  The third floor has officer quarters, and the fourth level is the bridge.  There are also observation decks at the stern and bow on the third level.

I have a bit of a reprieve during the plume study, since Steffi’s project does not focus on these waters.  It’s been a great opportunity to shadow other teams and learn about what they’re doing, as well as to explore more of the ship. Now that the first phase of the plume study is over, we are extending it farther out in the gulf to be able to examine a fresh water eddy that is showing up on satellite imagery.  After that, we will have about a 12-hour transit to the next line of stations, called the GAK (Seward) line, where Steffi (and I) will resume her testing. 


Did You Know?

It’s still foggy and the sea state is very calm compared to what everyone expected.  It’s great for the experiments, but doesn’t help with wildlife sightings.  We’re under the influence of a high pressure system currently, which is expected to keep things quiet at least through Wednesday.  At some point next week, we may have a low-pressure system pass through, which would increase wind speed and wave height. 


What Do You Want Kids to Learn from Your Research?

**Note: I’m asking the various scientists on board the same question.  Clay took five days to formulate this and it really captures the essence of his passion for his research and the effects of climate change.  It’s worth the read!

Clay: Recently, I was asked by Cat, our Teacher at Sea for this cruise, what I want members of the general public to take away from my work studying iron limitation of phytoplankton. Though I can provide her a superficial answer to my research question immediately, the motivations for my work go much deeper than answering “How does a micronutrient affect phytoplankton growth?”

There are two main levels at which I want to answer Cat’s question:

1. Proximal: Though phytoplankton are microscopic, they have macroscopic impacts.

2. Philosophical: Why bother in the quest for such knowledge?

Level 1: The Macroscopic Impacts of a Microscopic Organism 

Both human societies and phytoplankton communities are impacted by global climate change. Globally, humans are realizing the need to combat carbon emissions and mediate the effects of increasing global temperatures. Consequences of global climate change for us include mass emigration as sea levels rise and increased frequency of extreme weather events (e.g. droughts, wildfires). As a result, humans are racing to bridge political divides between countries, develop sustainable energy, and manage natural disaster response.

Phytoplankton, too, must respond to global climate change. As sea surface temperatures rise, phytoplankton will have to adapt. CO2 that is dissolved in seawater removes the precious materials some diatoms use to make their “shells” and takes away their protection. Dissolved CO2 can also alter the ability of micrograzers to swim and find food!

Melting glaciers are a double-edged sword. Glacial flour in freshwater runoff brings in vital nutrients (including iron) through the Copper River Plume and phytoplankton love their iron! But freshwater also works to trap phytoplankton in the surface layers. When all the nutrients are used up and you’re a phytoplankton baking in the heat of the sun, being trapped at the surface is super stressful!

As global climate change accelerates in the polar regions, phytoplankton in the Northern Gulf of Alaska are in an evolutionary race against time to develop traits that make them resilient to their ever-changing environment. Phytoplankton crossing the finish line of this race is imperative for us humans, since phytoplankton help to mediate climate change by soaking up atmospheric CO2 during photosynthesis to produce ~ 50 % of the oxygen we breathe!

Phytoplankton also form the base of a complex oceanic food web. The fresh salmon in the fish markets of Pike’s Place (Seattle, WA), the gigantic gulp of a humpback whale in Prince William Sound (AK) and even entire colonies of kittiwakes on Middleton Island (AK) are dependent on large numbers of phytoplankton. When phytoplankton are iron limited, they cannot grow or multiply (via mitosis). In a process called bottom up regulation, the absence of phytoplankton reduces the growth of animals who eat phytoplankton, the animals who eat those animals, and so on up the entire food chain.

Let us consider “The Blob”, an area of elevated sea surface temperature in 2015 to illustrate this point. “The Blob” limited phytoplankton growth and that of herbivorous fishes. As a result, the population of kittiwakes on Middleton Island crashed as the birds could not find enough fish to provide them the nutrients and energy to reproduce successfully. In this way, the kittiwake deaths were directly attributed to a lack of phytoplankton production.

Not only are phytoplankton ecologically important, they are commercially important. For consumers who love to fish (and for the huge commercial fisheries in the Northern Gulf of Alaska), the base of the food web should be of particular interest, as it is the harbinger of change. Fisheries managers currently use models of phytoplankton growth to monitor fish stocks and establish fisheries quotas. If sporadic input of iron from dust storms, glacial runoff, or upwelling stimulate phytoplankton to grow, fish stocks may also increase with the newfound food source. Because phytoplankton are inextricably linked to fish, whales, and seabirds, in years where nutrients are plentiful, you may well see more fish on kitchen tables across the U.S. and Native Alaskans may be able to harvest more seabird eggs.  

Level 2: The Nature of Science

As a supporter of place-based and experiential learning, I view myself as a student with a duel scientist-educator role. To succeed in these roles, I have to be able to combine reasoning with communication and explore questions like “How does science relate to society?” and “How do we foster scientific literacy?” What better way to think about these questions than embarking on a three-week cruise to the Pacific Subarctic?! Not only am I working with amazing Principal Investigators in an immersive research experience, I am able to collect data and think of creative ways to communicate my findings. These data can be used to build educational curricula (e.g. Project Eddy modules, R shiny apps, etc.) in an effort to merge the classroom with the Baltic room (where the CTD is deployed). But what’s the point of collecting data and sharing it?

Science is “a collaborative enterprise, spanning the generations” (Bill Nye) and is “the best tool ever devised for understanding how our world works” (Richard Dawkins). The goal of communicating my results in a way that touches the lives of students is two-fold. One aim is to allow them to appreciate the philosophy of science – that it is iterative, self-correcting, and built upon measurable phenomena. It is the best way that we “know” something.

The other aim is to allow students to engage in scientific discourse and build quantitative reasoning skills. As the renowned astrophysicist Neil DeGrasse Tyson has said, “When you’re scientifically literate the world looks very different to you and that understanding empowers you.” Using phytoplankton to model the scientific process allows students to enter into the scientific enterprise in low-stakes experiments, to question how human actions influence ecosystems, and to realize the role science plays in society. Ultimately, I want students to use my data to learn the scientific process and build confidence to face the claims espoused by the U.S. government and seen on Facebook with a healthy amount of skepticism and an innate curiosity to search for the truth.

Katie Gavenus: Don’t Forget the Phytoplankton! May 5, 2019

NOAA Teacher at Sea

Katie Gavenus

Aboard R/V Tiglax

April 26 – May 9, 2019

Mission: Northern Gulf of Alaska Long-Term Ecological Research project

Geographic Area of Cruise: Northern Gulf of Alaska – currently in transit from ‘Seward Line’ to ‘Kodiak Line’

Date: May 5, 2019

Weather Data from the Bridge

Time: 2305
Latitude: 57o 34.6915’
Longitude: 150o 06.9789’
Wind: 18 knots, South
Seas: 4-6 feet
Air Temperature: 46oF (8oC)
Air pressure: 1004 millibars
Cloudy, light rain

Science and Technology Log

Phytoplankton!  These organisms are amazing.  Like terrestrial plants, they utilize energy from the sun to photosynthesize, transforming water and carbon dioxide into sugars and oxygen.  Transforming this UV energy into sugars allows photosynthetic organisms to grow and reproduce, then as they are consumed, the energy is transferred through the food web.  With a few fascinating exceptions (like chemotrophs that synthesize sugars from chemicals!), photosynthetic organisms form the basis of all food webs. The ecosystems we are most familiar with, and depend upon culturally, socially, and economically, would not exist without photosynthetic organisms.

Indeed, productivity and health of species like fish, birds, and marine mammals are highly dependent upon the productivity and distribution of phytoplankton in the Gulf of Alaska. Phytoplankton also play an important role in carbon fixation and the cycling of nutrients in the Gulf of Alaska.  For the LTER, developing a better understanding of what drives patterns of phytoplankton productivity is important to understanding how the ecosystem might change in the future.  Understanding the basis of the food web can also can inform management decisions, such as regulation of fisheries.

niskin bottles on the rosette

Seawater captured at different depths by niskin bottles on the rosette transferred to bottles by different scientists for analysis.

To better understand these patterns, researchers aboard R/V Tiglax use the rosette on the CTD to collect water at different depths.  The plankton living in this water is processed in a multitude of ways.  First, in the lab on the ship, some of the water is passed through two filters to catch phytoplankton of differing sizes.  These filters are chemically extracted for 24 hours before being analyzed using a fluorometer, which measures the fluorescence of the pigment Chlorophyll-a.  This provides a quantitative measurement of Chlorophyll-a biomass. It also allows researchers to determine whether the phytoplankton community at a given time and place is dominated by ‘large’ phytoplankton (greater than 20 microns, predominantly large diatoms) or ‘small’ phytoplankton (less than 20 microns, predominantly dinoflagellates, flagellates, cryptophyte algae, and cyanobacteria).

Preparing filters

Preparing filters to separate large and small phytoplankton from the seawater samples.

For example, waters in Prince William Sound earlier in the week had a lot of large phytoplankton, while waters more offshore on the Seward Line were dominated by smaller phytoplankton.  This has important ramifications for trophic interactions, since many different consumers prefer to eat the larger phytoplankton.  Larger phytoplankton also tends to sink faster than small plankton when it dies, which can increase the amount of food reaching benthic organisms and increase the amount of carbon that is sequestered in ocean sediments.

The Chlorophyll-a biomass measurements from the fluorometer are a helpful first step to understanding the biomass of phytoplankton at stations in the Gulf of Alaska.  However, research here and elsewhere has shown that the amount of carbon fixed by phytoplankton can vary independently of the Chlorophyll-a biomass.  For example, data from 2018 in the Gulf of Alaska show similar primary productivity (the amount of carbon fixed by phytoplankton per day) in the spring, summer, and fall seasons even though the Chlorophyll-a biomass is much higher in the spring.  This is likely because of at least two overlapping factors.  Vertical mixing in the winter and spring, driven primarily by storms, brings more nutrients and iron into the upper water column. This higher nutrient and iron availability in the spring allow for the growth of larger phytoplankton that can hold more chlorophyll.  This vertical mixing also means that phytoplankton tend to get mixed to greater depths in the water column, where less light is available.  To make up for this light limitation, the phytoplankton produce more chlorophyll in the spring so they can more effectively utilize the light that is available.  This variation in chlorophyll over the seasons probably helps to make the phytoplankton community overall more productive, but it makes it problematic to use Chlorophyll-a biomass (which is relatively easy to measure) as a proxy for primary productivity (which is much more challenging to measure).

Phytoplankton sample in the flourometer

A sample of filtered, extracted phytoplankton is placed into the fluorometer.

To address the question of primary productivity more directly, researchers are running an experiment on the ship.  Seawater containing phytoplankton from different depths is incubated for 24 hours.  The container for each depth is screened to let in sunlight equivalent to what the plankton would be exposed to at the depth they were collected from.  Inorganic carbon rich in C13 isotope is added to each container as it incubates. After 24 hours, they filter the water and measure the amount of C13 the phytoplankton have taken up.  Because C13 is rare in ecosystems, this serves as a measurement of the carbon fixation rate – which can then be converted into primary productivity.

Phytoplankton samples from the rosette are also preserved for later analysis in various labs onshore.  Some of the samples will be processed using High Performance Light Chromotography, which produces a pigment profile.  These pigments are not limited to Chlorophyll-a, but also include other types of Chlorophyll, Fucoxanthin (a brownish pigment found commonly in diatoms as well as other phytoplankton), Peridinin (only found in photosynthetic dinoflagellates), and Diadinoxanthin (a photoprotective pigment that absorbs sunlight and dissipates it as heat to protect the phytoplankton from excessive exposure to sunlight).  The pigment profiles recorded by HPLC can be used to determine which species of plankton are present, as well as a rough estimate of their relative abundance.

A different lab will also analyze the samples using molecular analysis of ribosomal RNA.  There are ID sequences that can be used to identify which species of phytoplankton are present in the sample, and also get a rough relative abundance.  Other phytoplankton samples are preserved for microscopy work to identify the species present.  Microscopy with blue light can also be used to investigate which species are mixotrophic – a fascinating adaptation I’ll discuss in my next blog post!

It is a lot of work, but all of these various facets of the phytoplankton research come together with analysis of nutrients, iron, oxygen, dissolved inorganic carbon, temperature, and salinity to answer the question “What regulates the patterns of primary productivity in the Gulf of Alaska?”

There are already many answers to this question.  There is an obvious seasonal cycle due to light availability.  The broad pattern is driven by the amount of daylight, but on shorter time-scales it is also affected by cloud cover.  As already mentioned, vigorous vertical mixing also limits the practical light availability for phytoplankton that get mixed to greater depths.  There is also an overall, declining gradient in primary productivity moving from the coast to the deep ocean. This gradient is probably driven most by iron limitation.  Phytoplankton need iron to produce chlorophyll, and iron is much less common as you move into offshore waters.  There are also finer-scale spatial variations and patchiness, which are partly driven by interacting currents and bathymetry (ocean-bottom geography). As currents interact with each other and features of the bathymetry, upwelling and eddies can occur, affecting such things as nutrient availability, salinity, water temperature, and intensity of mixing in the water column.

View of horizon from station GAK

The early-morning view from station GAK on the ‘Seward Line.’ Patterns of primary productivity are driven both by amount of cloud cover and amount of daylight. During our two weeks at sea, we actually sampled at GAK1 3 separate times. The amount of daylight (time between sunrise and sunset each day) at this location increased by nearly 60 minutes over the two week cruise!

The current work seeks to clarify which of these factors are the most dominant drivers of the patterns in the Gulf of Alaska and how these factors interact with each other. The research also helps to determine relationships between things that can be more easily measured, such as remote-sensing of chlorophyll, and the types of data that are particularly important to the LTER in a changing climate but are difficult to measure across broad spatial scales and time scales, such as primary productivity or phytoplankton size community. Phytoplankton are often invisible to the naked eye.  It would be easy to overlook them, but in many ways, phytoplankton are responsible for making the Gulf of Alaska what it is today, and what it will be in the future.  Understanding their dynamics is key to deeper understanding of the Gulf.

Personal Log

The schedule along the Seward Line and as we head to the Kodiak Line had to be adjusted due to rough seas and heavy winds.  This means we have been working variable and often long hours on the night shift. It is usually wet and cold and dark, and when it is windy the seawater we use to hose down the zooplankton nets seems to always spray into our faces and make its way into gloves and up sleeves.  But we still manage to have plenty of fun on the night shift and share lots of laughs.  There are also moments where I look up from the task at hand and am immersed in beauty, wonder, and fascination. I get to watch jellies undulate gracefully off the stern (all the while, crossing my fingers that they don’t end up in our nets  — that is bad for both them and us) and peer more closely at the zooplankton we’ve caught.  I am mesmerized by the color and motion of the breaking waves on a cloudy dawn and delighted by the sun cascading orange-pink towards the water at sunset.  I am reminded of my love, both emotional and intellectual, for the ocean!

Float coats

We experienced a lot of wind, rain, waves, and spray from the high-pressure hose (especially when I was wielding the hose), but bulky float coats kept us mostly warm and dry.

Did You Know?

Iron is the limiting nutrient in many offshore ecosystems.  Where there is more iron, there is generally more primary productivity and overall productive ecosystems.  Where there is little iron, very little can grow.  This is different than terrestrial and even coastal ecosystems, where iron is plentiful and other nutrients (nitrogen, phosphorous) tend to be the limiting factors.  Because people worked from what they knew in terrestrial ecosystems, until about 30 years ago, nitrogen and phosphorous were understood to be the important nutrients to study.  It was groundbreaking when it was discovered that iron may be a crucial piece of the puzzle in many open ocean ecosystems.

Question of the Day:

Regarding sustainability and scalability of intensive ocean resource harvesting: If humans started eating plankton directly, what could happen? And a follow-up: Can we use algae from harmful bloom areas?

Question from Leah Lily, biologist, educator, and qualitative researcher, Bellingham, WA

I first shared this question with the zooplankton night crew.  The consensus was that it was not a good idea to harvest zooplankton directly for large-scale human consumption.  Some krill and other zooplankton are already harvested for ‘fish oil’ supplements; as demand increases, the sustainability of this practice has become more dubious.  The zooplankton night crew were concerned that if broader-scale zooplankton harvest were encouraged, the resource would quickly be overharvested, and that the depletion of zooplankton stocks would have even more deleterious consequences for overall ecosystem function than the depletion of specific stocks of fish. They also brought up the question of how much of each zooplankton would actually be digestible to humans.  Many of these organisms have a chitinous exoskeleton, which we wouldn’t be able to get much nutrition from.  So it seems like intensive ocean harvesting of zooplankton is likely not advisable.

However, when I talked with the lead phytoplankton researcher on board, she thought there might be slightly more promise in harvesting phytoplankton.  It is more unlikely, she thinks, that it would get rapidly depleted since there is so much phytoplankton out there dispersed across a very wide geographic scale.  Generally, harvesting lower on the food chain is more energy efficient. At every trophic level, when one organism eats another, only a fraction of the energy is utilized to build body mass. So the higher up the food web we harvest from, the more energy has been ‘lost’ to respiration and other organism functions.  Harvesting phytoplankton would minimize the amount of energy that has been lost in trophic transfer.  Unlike most zooplankton, most phytoplankton is easily digestible to people and is very rich in lipids and proteins.  It could be a good, healthy food source.  However, as she also pointed out, harvesting phytoplankton in the wild would likely require a lot of time, energy, and money because it is generally so sparse.  It likely would not be economically feasible to filter the plankton in the ocean out from the water, and, with current technologies, not particularly environmentally friendly.  Culturing, or ‘farming,’ phytoplankton might help to address these problems, and in fact blue-green algae/Spirulina is already grown commercially and available as a nutritional supplement.  And there may be some coastal places where ‘wild’ harvest would be practical.  There are a number of spots where excess nutrients, often from fertilizers applied on land that runoff into streams and rivers, can cause giant blooms of phytoplankton.  These are often considered harmful algal blooms because as the phytoplankton die, bacteria utilize oxygen to decompose them and the waters become hypoxic or anoxic.  Harvesting phytoplankton from these types of harmful algal blooms would likely be a good idea, mitigating the impacts of the HABs and providing a relatively easy food source for people.  However, it would be important to make sure that toxin-producing plankton, such as Alexandrium spp. (which can cause paralytic shellfish poisoning) were not involved in the HAB.

Frank Hubacz: Unimak Pass, May 4, 2013

NOAA Teacher at Sea
Frank Hubacz
Aboard NOAA ship Oscar Dyson
April 29 – May 10, 2013

 

Mission: Pacific Marine Environmental Laboratory Mooring Deployment and Recovery

Geographical Area of Cruise: Gulf of Alaska and the Bering Sea

Date: May 5, 2013

 Weather Data from the Bridge (0300):

Partly cloudy, S Winds, variable, currently 3.71 knots
Air Temperature 2.8C

Relative Humidity 73%

Barometer 1025.1 mb

Surface Water Temperature 0.10 C

Surface Water Salinity 31.66 PSU

Seas up to 5 ft

Science and Technology Log

Once we completed our mooring work from Gore Point through to Pavlof Bay, we sailed on to Unimak Pass, nearly 400 miles away, and then entered into the Bering Sea.  Unimak Pass is a strait (wide gap) between the Bering Sea and the North Pacific Ocean in the Aleutian Island chain of Alaska.  Upon arrival at our first station, we started the process of deploying our CTD sampling unit at predetermined points as well as MARMap Bongo casts(discussed in my next blog) when specified, within a region forming a rectangular “box” north of the pass.  If you have been following my voyage using NOAA ship tracker, hopefully you now understand why we appeared to have been “boxed in” (I can hear the groans from my students even out here in the Bering Sea). It is important to understand the ocean waters of this region given that it is a major egress between the North Pacific Ocean and the Bering Sea.  Therefore it serves as an important pathway between these two water bodies for commercially important fish stock as well as serving as a major commercial shipping route.

Unimak Pass

Unimak Pass

 A CTD (an acronym for conductivity, temperature, and depth) is an instrument used by oceanographers to measure essential physical properties of sea water.  It provides a very comprehensive profile of the ocean water to help better understand the habitat of important marine species as well as charting the distribution and variation of water temperature, salinity, and density.  This information also helps scientist to understand how variations in physical ocean properties change over time.  The  CTD is made up of a set of small probes attached to a large stainless steel wheel housing. The sensors that measure CTD are surrounded by a rosette of water sampling bottles (niskin bottles) that individually close shut by an electronic fired trigger mechanism initiated from the control room on-board the ship.  The rosette is then lowered on a cable down to a depth just above the seafloor.  The science team is able to observe many different water properties in real time via a conducting cable connecting the CTD to a computer on the ship. A remotely operated device allows the attached water sampling bottles to be closed (sample collected) at selective depths as the instrument ascends back to the surface.

 

CTD Unit

CTD Unit

Here I am in my hot rain pants helping to deploy the CTD

Here I am in my hot colored rain pants helping to deploy the CTD.  Notice the niskin bottles?

Monitoring the drop with Peter

Monitoring the drop with Peter

Monitoring the CTD deployment

Data screens in the lab

On this cruise, our CTD was equipped to collect real-time water column measurements of conductivity, temperature, density, dissolved oxygen, salinity, chlorophyll levels, and light as the unit traveled down through to a set point just above the ocean floor.  Additionally, water samples for determining concentrations of nutrients (nitrate (NO3-1), nitrite (NO2-1), ammonium (NH4+), phosphate (PO4-3), and silicates (SiO4-4), dissolved oxygen, dissolve inorganic carbon, and chlorophyll were measured at specified depths within the water column as the unit was raised back to the surface.  Replicate measurements of some chemical constituents measured on the ascent are completed to help support the reliability of  the dynamic measurements of these same species made on the drop.  All of the nutrient samples are then frozen to -80C and brought back to the lab on shore for analysis.  Dissolved oxygen, dissolved inorganic carbon, and chlorophyll samples are also treated according to unique methods for later detailed analysis.

The sampling begins!

The sampling begins from a niskin bottle!

Filling the sampling vials to be stored for later analysis

Filling the sampling vials to be stored for later analysis

Peter placing samples in the freezer

Peter placing samples in the freezer

Scott preparing the chlorophyll samples

Scott preparing the chlorophyll samples

Our first CTD cast from the “Unimak Box” began with my shift, a bit after midnight, on May 3rd and ended 32 hours later on May 4th.  The science crew worked nonstop as they completed 17 different CTD casts. Again, it was impressive to see the cooperation among the scientists as each group helped one another complete CTD casts, launch and retrieve Bongo nets, and then collect the many different samples of water for testing as well as the samples of zooplankton caught in the bongo nets.  My task was to collect nutrient water samples from each CTD cast.  As the water depth increased so did the number of samples that were collected.  During our sampling water depths ranged from approximately 50 meters (5 samples) up to 580 meters (11 samples).  On our last cast the air temperature was -2.3o C with water temperature reading 2.90 C. Seas were relatively calm and we were able to see many different islands in the Aleutian chain.

Personal Log

It was rewarding to be able to help the team collect water samples for nutrient testing, especially given that we are able to sample many of these same nutrient species in our chemistry lab at Franklin Pierce.  I want my students to know that I practiced “GLT” when collecting nutrient samples making certain to rinse each sample bottle and sampling syringe at least three times before each collection.  Want to know what “GLT” references…ask one of my students!

My most “interesting” time on board ship happened during our first night of CTD testing along one of the lines of the Unimak Box.  At 2:45 am Peter, Douglas, and I were recording flow meter values from the previous bongo net tow on the side quarter-deck.  I was writing values down on a clip board as Peter read the values off to me.  I happened to glance over the deck towards the sea when I noticed an unusually large wave about 2 meters out from the boat traveling towards us.  Suddenly it crashed on top of us knocking us to the deck floor.  Water flooded all around us and through the doors of our labs.  I immediately grabbed onto one of the ship’s piping units and held on tight as the water poured back off the deck.  In an instant the sea was calm again after the “rogue” wave released its energy on our ship.  Because Peter and I fell onto the deck our clothes became completely soaked with icy cold seawater.  Upon standing, we checked on each other and then immediately began retrieving empty sampling bottles and other lab paraphernalia as they floated by in the water emptying off the deck.  Douglas was able to hold-on to the CTD and remained standing and dry under his rain suit.  This is the first, and I hope the last, “rogue” wave that I ever experience.  Fortunately, no one was lost or injured and we were able to retrieve all of our equipment with one exception…the clip board of data log entries that I was holding!

I must admit that I am disappointed at the limited internet access while on board ship.  I find it somewhat disheartening that I have not been able to write the consistent blogs promised to you telling of my adventures.  Hopefully this will improve as we change course and you will continue to follow along.

IMG_7099

View as I traveled to work!

Islands of the Aleutians.

Islands of the Aleutians.

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Island hopping!

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Not all islands are completely snow covered.

 

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Gina Henderson: Samples Aplenty, August 23, 2012

NOAA Teacher at Sea
Prof. Gina Henderson
Aboard NOAA Ship Ronald H. Brown
August 19 – 27, 2012

Mission: Western Atlantic Climate Study (WACS)
Geographical area of cruise: Northwest Atlantic Ocean
Date: Thursday, August 23, 2012
Weather conditions: calm conditions overnight leading to widespread radiation fog immediately following sunset. Ship had to make use of foghorn for a couple of hours overnight. Today, cloudy with possible rain showers. Winds SW from 10-15 kts, with gust up to 20 in rain showers. Seas from the SW at 3-5 ft.

Science and Technology Log

WACS Field Campaign Update:

This morning we reached the 3-day mark for sampling at station 1, which was in the high chlorophyll concentration off of Georges Bank. During these 3 days, we have been continuously sampling aerosols using both the Sea Sweep and the Bubble Generator (see last post for descriptions of each of these methods).

Some issues that have cropped up throughout this time are linked to our extremely calm and settled weather. Although the calm winds have made for minimal seas, ideal conditions for the Sea Sweep, those scientists sampling ambient air have been picking up ship exhaust in their measurements, despite the bridge keeping our bow head-to-wind. However, during our transit this complication should not be an issue and ambient sampling can take place continuously.

Conductivity, Temperature and Depth:

CTD rosette

Conductivity, temperature, and depth (CTD) rosette after deployment. Niskin bottles can be tripped at different depths for seawater sampling at various levels.

We also took a Conductivity, Temperature and Depth (CTD) profile using the CTD rosette on the 21st, collecting water near the bottom at 55m and other levels on the way to the surface.  These water samples were utilized by numerous scientists on board for experiments such as, testing for surface tension, biological testing and chlorophyll measurement.

The science plan for today involved one final CTD cast while at station 1, with all Niskin bottles being tripped at 5m. This large volume is necessary for a Bubble Generator experiment that will be run with this CTD water during the transit to station 2.

After the CTD cast was completed, the Sea Sweep was recovered and other necessary preparations for the transition to our new station. While underway for approximately 24 hours, intake hoses were switched to enable sampling of ambient aerosols along the way.

How to sample aerosols?

One of the tasks that I have been helping out with is the changing of aerosol impactors that are used to collect aerosol samples. These impactors consist of metal cylinders with various “stages” or levels (upper left photo below). Each level has different sizes of small holes, over which a filter is laid. During sampling, these impactors are hooked up to intake hoses where airflow is pumped through them and as the air is forced through the different “stages” or levels, the aerosols are “impacted” on the filters.

Filters being changed inside aerosol impactors (upper left). Picture of me unhooking impactors from inlet hoses for filter switching (upper right). Kristen just finished changing filters in a clean box (bottom).

This all seems simple enough…. However can be a little more cumbersome as the impactors are heavy, climbing up ship ladders with heavy things can be tricky depending on current sea state, and 2 of our impactor changes happen routinely in the dark, making things a little interesting at times!

Seawater sampling for chlorophyll:

Megan filtering raw seawater for chlorophyll extraction and measurement.

Another type of sampling I have helped out with involves the filtration of raw seawater to extract chlorophyll. This is done in the seawater van where we have a continuous flow of in situ water that is taken in at the bow at a depth of approximately 5m. This is done with two different types of filters, a couple of times a day. The photo below shows Megan running a sample through one type of filter, which will later be prepared with an acetone solution and after a resting period, be measured for chlorophyll concentration using a fluorometer.

Lots of sightings during transit:

As we headed south during our transit to station 2, we had an afternoon full of sightings! An announcement from the bridge informing us that we were now in “shark infested waters” sent an air of excitement around the ship as we all raced to the bridge for better viewing. Some loggerhead turtles were also spotted. Our final sighting of the day was a huge pod of porpoises riding the wake from our bow.

Pod of porpoises riding the bow wave during our transit south to station 2.

Everyone races to the bridge after an announcement about “shark infested waters!”

Gina Henderson: 30 Days of Science in 9 Days… August 21, 2012

NOAA Teacher at Sea
Prof. Gina Henderson
Aboard NOAA Ship Ronald H. Brown
August 19 – 27, 2012

Mission: Western Atlantic Climate Study (WACS)
Geographical area of cruise: Northwest Atlantic Ocean
Date: Tuesday, August 21, 2012

Weather Data: Winds light and variable less than 10 kts. Combined seas from the SW 3-5 ft, lowering to 2-4 ft overnight. Into Wednesday 22nd, winds continue to be light and variable, becoming NE overnight less than 10 kts. 

Science and Technology Log

WACS Field Campaign Update

Greetings from Georges Bank off the coast of New England! This is our first of 2 sampling stations during the Western Atlantic Climate Survey (WACS) field campaign, over the next 9 days. Our current location was chosen due to its high chlorophyll values, indicating productive waters. Shortly after our arrival here approximately 0700 on the 20th, the Sea Sweep instrument was deployed, and aerosol collection began (see picture below). However, for many of the scientists onboard, data collection began almost immediately after disembarking Boston, on the 19th.

The Sea Sweep

Photographs showing the Sea Sweep (top left), deployment of the Sea Sweep (bottom left), and Sea Sweep underway with bubble generation and aerosol collection taking place (right).

Upon my arrival to the ship in Boston, I quickly learned that this field campaign is a little unusual due to the sheer volume of equipment being utilized, and the short nature of the cruise itself. As we disembarked the Coast Guard pier in Boston, a running joke being echoed around the ship was, “30 days of science in 9 days…. ready, set, and GO!”

Science vans on deck

Looking from the bow towards the bridge, not visible in this photograph due to the mobile lab vans that have been installed on the deck for this cruise.

Over 9 mobile research vans were loaded onto the Ron Brown in preparation for this campaign making for a “low-riding ship”, joked our captain at our welcome meeting on the 19th. Each van contains multiple instruments, computers, ancillary equipment and supplies, and they also serve as research labs for the science teams to work in.

During the past two days, I have been making the rounds to each of these lab vans to hear more about the science taking place in each. With the help of the Chief Bosun, Bruce Cowden, I have also been able to shoot some video of these visits. With the assistance of Bruce, I am learning how to stitch these clips together into some fun short video pieces, so stay tuned for more to come!

A Little about the Sea Sweep

The Sea Sweep instrument consists of floating pontoons that hold a metal hood. The hood is mounted on a frame that protrudes below the water line when deployed, with two “frizzles” or “bubble maker” nozzles that air is pumped through to produce freshly emitted sea spray particles. These particles are then collected through two intake pipes attached to the hood, and are piped into the AeroPhys van. From there, samples are collected and also the intake is drawn into other vans for additional measurements.

Comparison of Sea Sweep Data with “the Bubbler”

Aerosol generator

Scientist Bill Keene from University of Virginia talking to me about “the bubbler”.

Sea spray particles are also being produced and collected via another method onboard, allowing for comparison with the Sea Sweep data. The picture below shows bubbles being generated in seawater that is fed into a large glass tower. This is an aerosol generator (a.k.a. “the bubbler”) brought on board by the University of Virginia. Through sampling with both the Sea Sweep and the bubbler, a greater size range and variety of aerosols can be sampled throughout the cruise.

Personal Log

After waiting a day or so for things to settle down and instruments to get up and running, I was eager to dive right in and be put to work on board. After an announcement made by the chief scientist, Trish Quinn, during our first evening meeting I was quickly solicited by a few different people to help with a range of tasks. So far these have included helping change impactor filters necessary for aerosol sampling 3 times a day (1 of these switches has been happening at 0500, making for some early mornings but pretty sunrises), getting raw sea water samples every 2 hours from different sampling points on board, preparing sea water samples for different analysis such as surface tension, and measuring samples for chlorophyll, dissolved organic carbon and particulate organic carbon.

Amongst all the sampling taking place however, it has been nice to take a break every once in a while to enjoy the extremely calm and settled weather we are having. A very memorable moment yesterday occurred when an announcement over the ship’s intercom alerted all aboard to a pod of whales off the port bow. It was nice to see the excitement spread, with both crew and science team members racing to the bow in unison with cameras in tow!

fun pics aboard

Early morning sky after an impactor filter change (left). All hands rush to the bow after whale sighting is announced (right).

Bhavna Rawal: Conductivity, Temperature, Depth (CTD) and Water Testing, August 7, 2012

NOAA Teacher at Sea
Bhavna Rawal
Aboard the R/V Walton Smith
August 6 – 10, 2012

Mission: Bimonthly Regional Survey, South Florida
Geographic area: Gulf of Mexico
Date: Aug 7, 2012

Weather Data from the Bridge:
Station: 6.5
Time: 21.36 GMT
Longitude: 080 17’ 184
Latitude: 250 3’ 088
Water temp: 29.930 oC
Wind direction: East
Wind speed: 8 knots
Sea wave height: 3 ft

Science and Technology log:

Hello students! We know how to do water testing in our lab class using the testing kit. Today, I am going to explain to you the way ocean water is sampled and tested in the South Florida coastline.

Our 5 day cruise consists of over 80 stations along the Atlantic and Gulf coast of Florida.  At each station we take water samples, and at about 20 of the stations we tow nets to catch fish, seaweed or plankton and sometimes scuba dive to recover the instruments mounted on the seafloor.

Our journey begins at station #2 at Dixie shoal, which is near Miami; you can see this on the South Florida bimonthly Hydrographic survey map below (see fig).

South Florida Bimothly Hydrographic Survey map

South Florida Bimothly Hydrographic Survey map

At each station we performed CTD (conductivity, temperature and depth) operations. The CTD is a special instrument to measure salinity, temperature, light, chlorophyll and the depth of water in the ocean. It is an electronic instrument mounted on a large metal cage that also contains bottles to collect samples.  These bottles are called niskin bottles and every oceanographer uses them.  They are made of PVC and are specially designed to close instantaneously by activation from the computer inside the ship. Collecting water samples at various depths of the ocean is important in order to verify in the lab that the instruments are working properly. Each bottle has an opening valve at the bottom and top to take in the seawater. The top and bottom covers are operated by a control system. Once a certain depth is reached, the person sitting at the control system triggers and it closes the bottles. You can control each bottles through this system to get a pure water sample from different depths. For example, when the ocean floor is 100 meters deep, water is sampled from the surface, at 50 meters deep, the very bottom.

Hard hat and life vest on and ready for CTD

Hard hat and life vest on and ready for CTD

The CTD instrument is very large, and is operated by a hydraulic system to raise it, to place it and lower down into the ocean. Rachel (another fellow member) and I were the chemistry team; we wore hard hats and life vests while we guided the CTD in and out of the water. This is always a job for at least two people.

Guiding CTD in and out of water

Guiding CTD in and out of water

The team usually closes several bottles at the bottom of the ocean, in the middle layer and surface of the ocean. We closed the bottles in the middle layer because the characteristics of the water are different from at the bottom and the surface.  Remember, the ocean water is not all the same throughout, at different depths and locations it has different chemical characteristics. We closed two bottles per layer, just in case something happened with one bottle (it is not opened properly, for example) then the other bottle can be used.

Taking water sample out of CTD bottles

Taking water sample out of CTD bottles

Rachel and I took water samples from the CTD bottles and used them in the lab to conduct experiments. Before I explain the analysis, I want to explain to you the importance of it, and how a “dead zone” can happen. Remember phytoplankton need water, CO2, light and nutrients to live and survive. The more nutrients, the more phytoplankton can live in water. As you all know, phytoplankton are at the base of the food chain. They convert the sun’s energy into food. Too many nutrients mean too much phytoplankton.

  1. If certain species of phytoplankton increase, it increases the chance of a harmful algal bloom. Too much of one kind of plankton called the dinoflagellates can release toxins into the water which harms the fish and other ocean life and it can even cause people to feel like they have a cold if they swim in the water that has those plankton.
  2. Large amounts of plankton die and fall to the sea floor, where bacteria decompose the phytoplankton. Bacteria use available oxygen in water. The lack of oxygen causes fishes and other animals die. The zone becomes ‘the dead zone’.
    We prepare the sample for nutrient analysis to measure nutrients such as nitrate, nitrite, phosphate, ammonium and silicate in the water.
    We also prepare the sample for chlorophyll analysis. In the lab, we filter the phytoplankton out of the water. Phytoplankton contains special cells that photosynthesize (chloroplasts) which are made of chlorophyll. If we know the amount of chlorophyll, we can estimate the amount of phytoplankton in a given area of the ocean.

filtering the phytoplankton out of the water

Filtering the phytoplankton out of the water

Preparing the sample for nutrient analysis

Preparing the sample for nutrient analysis

Phytoplankton needs carbon dioxide to grow. Carbon dioxide analysis is useful because it provides an estimate of total carbon dioxide in the ocean.  It is also important in understanding the effects of climate change on the ocean.  If you increase the amount of CO2 in the atmosphere (like when you drive cars), it enters into the ocean.  If you think about a can of soda it has a lot of CO2 dissolved into it to make it fizzy, and it also tastes kind of acidic.  This is similar to when CO2 dissolves into seawater.  When the ocean becomes more acidic, the shells of animals become weaker or the animals cannot produce the shells at all.

Colored dissolved organic matter (CDOM) analysis informs us where this water comes from.  The dissolved organic matter comes from decomposing plants, and some of these dead plants entered the water through rivers.  You can tell for example that water came from the Mississippi River because of the CDOM signal.  You can then follow its circulation through the ocean all the way to the Atlantic.

From the CTD instrument, we measured temperature, light, salinity, oxygen etc. and graphed it on a computer (see figure) to analyze it.

Measured temperature, light, salinity, oxygen etc. and graphed it

Measured temperature, light, salinity, oxygen etc. and graphed it

Generally, I see that ocean surface water has high temperature but low salinity, low chlorophyll, and low oxygen. As we go deeper into the sea (middle layer), temperatures decrease, dissolved oxygen increases, chlorophyll and salinity increases. At the bottom layer, chlorophyll, oxygen, temp and salinity decrease.

Personal Log:

I arrived on the ship Sunday evening and met with other people on the team, tried to find out what we are going to do, how to set up, etc. Asked so many questions… I explored my room, the kitchen, the laundry, the science lab, the equipment, etc. Nelson (the chief scientist) gave me a really informative tour about the ship, its instruments and operations. He showed the CTD m/c, the drifter, the wet lab etc. He also gave me a tour of a very important instrument called the “flow-through station” which is attached to the bottom of the ship. This instrument measures temp, salinity, chlorophyll, CDOM, when the boat drives straight through a station without stopping. I was really stunned by how precise, the measurements taken by this instrument are.

flow-through station

Flow-through station

The next morning, Nelson explained that if we have enough tide the ship would leave. We had to wait a bit. As soon as we got the perfect tide and weather, R/V Walton Smith took off and I said ‘bye bye’ to Miami downtown.

‘bye bye’ to Miami downtown

‘Bye bye’ to Miami downtown

I learn so much every day in this scientific expedition. I saw not only real life science going on, but efficient communication among crew members. There are many types of crew members on the ship: navigation, technology, engineering, and scientific. Chief scientists make plans on each station and the types of testing. This plan is very well communicated with the navigation crew who is responsible for driving the ship and taking it to that station safely. The technology crew is responsible for efficient inner working of each scientific instrument. 10 minutes before we arrive on a station, the ship captain (from navigation crew) announces and informs the scientific team and technology team in the middle level via radio. So, the scientific team prepares and gets their instruments ready when the station arrives. I saw efficient communication and collaboration between all teams. Without this, this expedition would not be completed successfully.
I have also seen that safety is the first priority on this oceanic ship. When any crew member works in a middle deck such as CTD, Net Tow etc, they have to wear a hard hat and life jacket. People are always in closed toe shoes. It is required for any first timer on the boat to watch a safety video outlining safe science and emergency protocol. People in this ship are very friendly. They are very understanding about my first time at sea, as I was seasick during my first day. I am very fortunate to be a part of this team.

The food on the ship is delicious. Melissa, the chef prepares hot served breakfast, lunch and dinner for us. Her deserts are very delicious, and I think I am going to have to exercise more once I come back to reduce the extra weight gained from eating her delicious creations!

Watch TV, play cards and have dinner together

Watch TV, play cards and have dinner together

My shift is from 5 a.m. to 5 p.m. and I work with Rachel and Grant. After working long hours, we watch TV, play cards and have dinner together. I am learning and enjoying this expedition on the ship Research Vessel Walton Smith.

Question of the Day:

Why we do water testing in different areas of river and ocean?

New word:

Colored dissolved organic matter (CDOM)

Something to think about:

How to prevent dead zone in an ocean?

Animals Seen Today:
Two trigger fishes
Three Moon Jelly fishes
Five Crabs

Did You Know?
In ship, ropes called lines, kitchen called galley, the place where you drive your ship is called bridge or wheel house.

Dave Grant: Horse Latitudes, February 22, 2012


NOAA Teacher at Sea

Dave Grant
Aboard NOAA Ship Ronald H. Brown
February 15 – March 5, 2012

Mission: Western Boundary Time Series
Geographical Area: Sub-Tropical Atlantic, off the Coast of the Bahamas
Date: February 22, 2012

Weather Data from the Bridge

Position:26.30 N – 75.42 W
Windspeed: 0
Wind Direction: Calm
Air Temperature: 29 C
Water Temperature: 24 C
Atm Pressure: 1025
Water Depth: 4,410 meters
Cloud Cover: 0
Cloud Type: Slight haze

Science/Technology Log:

We are becalmed and even the veteran sailors onboard are remarking on how flat the sea has become. At about 30 degrees North and South Latitude, moist, low pressure air that was heated and lifted from the surface at the Equator has cooled and is now plunging back down to Earth, forming a line of light winds in a band across the sea. This dry, high pressure air becomes the Trade winds as it is drawn back towards the Equator along the sea surface in what is called a Hadley Cell (After its discoverer). We seem to be on the edge of this meteorological milepost, which was more than a nuisance in the days of sail. If stranded in its pattern too long, food and especially drinking water became an issue, and the first to suffer would be animals being transported from the Old World to the New. Legend has it that subsequent voyagers would come across their carcasses…hence the name Horse Latitudes.

While observing ships returning to port near his home, sixteen year-old future rock star Jim Morrison (The DOORS)  composed what is perhaps his most eerie ballot – Horse Latitudes.

“When the still sea conspires an armor
And her sullen and aborted
Currents breed tiny monsters
True sailing is dead
Awkward instant
And the first animal is jettisoned
Legs furiously pumping”

However, the stable ship makes deck work easier and I am catching up on samples under the microscope, including some of my own tiny “monsters” that the currents have bred.

It is the astonishing variety of life that makes the sea such a fascinating
hunting ground. Get a tow-net, dredge and simple microscope,
and a new world is yours – a world of endless surprises.”

(Sir Alister Hardy)

The chief survey technician set me up  with his  flow-through seawater system and I can leave a net under it to continuously gather plankton. I have noticed some patterns already.
One: Phytoplankton is scarce compared to temperate waters off of New Jersey, and this helps account for the clarity and
brilliant blue color of the water. The absence of large rivers here adding nutrients to the system, and little coastal
upwelling,  means that there is little to fertilize plantlife.
Two: More accumulates in the nets at night, confirming that Zooplankton rises to the surface at in the dark. This diurnal
pattern of the plankton community has been well documented ever since biologists and fishermen went to sea.
Three: Also, there is much more plankton at the surface than in deeper water. This is no surprise since sunlight is the
key ingredient at the surface of this ocean ecosystem.
Four: Creatures from offshore tend to have a more feathery look about them than inshore species. This added surface
area may use the turbulence to help support them near the surface  and increase their buoyancy.

It is said:  “Turn off the sun, and the oceans will starve to death in a week.”  It is assumed that among other stresses on the Biosphere that accompany disastrous impacts of large asteroids, dust and ash from these rare collisions block out enough sunlight to stifle photosynthesis, causing Phytoplankton (The “Pasture of the Sea”) to waste away, and setting the stage for the collapse of the Food Chain and mass extinction events. Fortunately we have plenty of brilliant sunshine here and no celestial catastrophes on the horizon.

Some of the most interesting Zooplankton are the Pteropods, the Sea Butterflies.

   
Empty shell and live pteropod specimen
(Images on the Ron Brown by Dave Grant)

The renowned oceanographer Alister Hardy used them as indicators of different water masses flowing around the British Isles; and New England’s great oceanographer, Alfred Redfield correlated their drifting with the anti-clockwise circulation of water in the Gulf of Maine. Although most are small and less than an inch long, they feed on a variety of creatures and in turn become food for many others. In surface waters they gather phytoplankton, some utilizing cilia and mucus to sweep food to the mouth; but in deeper waters, others are carnivorous.

I am informed by our English colleagues that on Europe’s fishing grounds, they are sometimes fed upon by herring, cod and haddock; which is bad news for British fishermen, whose catch rapidly decays and is not marketable. Such fish are referred to as “black gut” or “stinkers.”

How concentrated are pteropods? Whales and seabirds that we hope to encounter later in the cruise are sustained by them, and in the warmer waters of the Atlantic, at relatively shallow depths and on the tops of submerged peaks at around 2,000 meters, R.S. Wimpenny reports considerable deposits of “pteropod ooze” from their descending shells, covering an estimated 1,500,000 square kilometers of the bottom of the Atlantic (An area the size of the Gulf of Mexico.). Like the Foraminifera, in deeper waters the aragonite in their shells (a more soluble form of calcium carbonate) dissolves, and other sediments like silicates from diatoms accumulate instead. Check out any oceanography text and you are likely to find a picture of this biogenic pteropod mud, as well as other types of deposits.

At least 90% of the animals in the ocean are meroplankton – spending time in this itinerant stage before becoming adults. This phase may vary from a few days to over a year, depending on the creature. (European eels larva are the long distance champions; for over a year, drifting from below us in their Sargasso Sea breeding grounds, all the way to rivers in Britain and France.)

Drifting larvae are cheap insurance for a species, filling the surrounding habitat with individuals of your own kind, settling in new areas and expanding ranges, and particularly, not lingering around their birthplace and competing with the parent stock. However, most individuals simply end up as food for other creatures that are higher on the food chain.

Not surprising, there are copepods, the “cattle of the sea” grazing on smaller organisms.

  
(Images on the Ron Brown by Dave Grant)

Calanus finmarchicus is sometimes called the most abundant animal in the world and is found throughout the oceans, sustaining many types of marinelife; even right whales and basking sharks off the coast of New England.

Other sea soup and children of the sea that author David Bulloch likes to call them, drift by me and swim circuits trapped by surface tension in the water drop under the microscope.

  
Radiolaria are single cell Protozoa that not only ensnare food with mucous, but harbor mutualistic algae
among their spines. (100 x’s)


More live pelagic snails. (Pteropod means winged foot.)

  
An empty shell with  copepod sheltered inside. Other skeletons filled with Paramecia, and a mixed sample of shells
and dust particles.  (Images on the Ron Brown by Dave Grant)

Now that is calm, everyone seems to have their sea legs and are comfortable talking about their bouts of mal de mer.
Here is the worst story about sea sickness I have come across:

 From Dave Grant’s collection of sea stories:
The world’s worst tale of seasickness.
As told by Ulysses S. Grant in his Memoirs

One amusing circumstance occurred while we were lying at anchor in Panama Bay. In the regiment there was a Lieutenant Slaughter who was very liable to seasickness. It almost made him sick to see the wave of a table-cloth when the servants were spreading it. Soon after his graduation [from West Point] Slaughter was ordered to California and took passage by a sailing vessel going around Cape Horn. The vessel was seven months making the voyage, and Slaughter was sick every moment of the time, never more so than while lying at anchor after reaching his place of destination. On landing in California he found orders that had come by way of the Isthmus [Panama], notifying him of a mistake in his assignment; he should have been ordered to the northern lakes. He started back by the Isthmus route and was sick all the way. But when he arrived back East he was again ordered to California, this time definitely, and at this date was making his third trip. He was sick as ever, and had been so for more than a month while lying at anchor in the bay. I remember him well, seated with his elbows on the table in front of him, his chin between his hands, and looking the picture of despair. At last he broke out, “I wish I had taken my father’s advice; he wanted me to go into the navy; if I had done so, I should not have had to go to sea so much.”

Poor Slaughter! It was his last sea voyage. He was killed by Indians in Oregon.