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Going With the Flow

February 13th, 2017 by Stephanie Uz

Trying to sleep on a trampoline while somebody is jumping on it – this is how it feels during many nights at sea as the ship zig-zags in an imaginary box around our drifting instruments in the North Pacific during winter. This is when biological activity is lowest, but clearly there is no absence of physical forces, such as waves. Clearly.

The aim of this expedition is to find phytoplankton and measure their characteristics using light detectors, cameras and microscopes. From my perspective as an oceanographer who uses satellite data to explore large scale physical forcing of biology, this is a great chance to think about the smaller-scale forcing mechanisms that supply nutrients to the phytoplankton. And I am glad to get acquainted with the optical and biological instruments and methods being used and tested here at sea.

Hemispheric view by Suomi-NPP VIIRS on Feb 9, 2017 in true color. Clouds and airborne particles are white; ocean, blue. The ship’s track is shown in the red line. Station M is our last sampling site. NASA/ Norman Kuring

 Slow Water, Low Biology

We began the campaign near Hawaii at the end of January in the North Pacific subtropical gyre, which has a predominate slow-moving circulation pattern that causes nutrient-depleted surface water. We experienced plenty of swell from distant storms – lab equipment had to be tied down, and chairs slid across the galley. Still, nutrient-rich deep water remained far below the well-mixed surface waters.

The water was exceptionally clear. Sunlight penetrated deeper than 150 meters (500 feet). In spite of the dearth of nutrients, our imaging systems revealed some phytoplankton! They appeared malnourished, but surprisingly diverse nonetheless.

In the absence of strong currents or other flow patterns, the Wirewalker instrument drifted westward making daily clockwise loops with the Earth’s rotation. I was excited to see its path mapped with inertial oscillations so clearly visible. Although they are always present, it is rare to see them this obviously as they are usually hidden by stronger forcing.

A plot of the Wirewalker’s track as it drifted freely at our second site for three days. Each point in the plot represents one hour. SOI/ Melissa Omand

Fast Water, More Biology

The end of our sampling campaign is approximately 250km (150 miles) west of central California over a site called ‘Station M.’ This location is typically more productive, being in the California Current that brings cooler water southward from the subpolar gyre.

Additionally, we arrived between low pressure frontal systems that have been pummeling the west coast with strong winds, rain and snow over the past month. These strong weather systems cause wind-mixing at the surface of the ocean, bringing nutrients up from depth. Sampling revealed a warmer, fresher top 30 meters (100m) above cooler, nutrient-rich water.

Immediately, the instruments monitoring phytoplankton and nutrients began registering significantly higher quantities than anything we saw earlier in the expedition: even more diverse and even more abundant. Collectively, this team has gathered an amazingly rich data set of measurements and images that makes the discomfort of sleeping on a trampoline all worth it.

Stephanie Schollaert Uz monitors the speed and direction of water flowing under the ship with the Acoustic Doppler Current Profiler. SOI/ Monika Naranjo Gonzalez

Measuring the Pulse of the Ocean

February 11th, 2017 by Ryan Vandermeulen

Act 1: Blowin’ in the wind

At the unholy hour of 0400, I find myself on the aft deck of the world-class research vessel Falkor, bubbling with excitement stemming from a unique combination of four shots of espresso, generally being a morning person, and, most importantly, preparing to test an experimental device that I have put my blood, sweat, and tears into. As I bear-hug my newly collected bucket full of seawater on the rocking transit back to the wet lab, I take a moment to silently congratulate myself on the superb display of stamina and posture; it appears that my sea legs have finally decided to make an appearance. The sun will be coming up soon. It’s a Bob Dylan kind of day. Time to turn up the music and get to work.

Act 2: There ain’t no party like a plankton party

Ryan Vandermeulen, optical oceanographer, is testing this instrument at sea for the first time. The experimental “photosynthetron” (a.k.a. electro-squid 4000) serves as an incubation chamber for seawater samples. SOI/ Vandermeulen

In addition to being an eclectic lab DJ, one of my roles as a scientist aboard this righteously amazing research vessel is to investigate the rates of biological activity among microscopic communities within the ocean. The invitees to this epic microbial festival include bacteria, viruses, zooplankton, larval fish, and phytoplankton (algae). The photosynthetic members of this microscopic plankton community (PHYTO-plankton) are the base of a complex ocean food web, and have a large cascading ecological impact on the abundance and diversity of fisheries that we depend on. In addition, phytoplankton play a significant role in the global cycling of carbon, as well as the production of oxygen we breathe. Just like the plants in your garden, phytoplankton utilize carbon dioxide and micronutrients in the seawater – along with various light harvesting pigments which capture sunlight at different wavelengths – to create new cell bodies.

A byproduct of this magnificent life-giving process of photosynthesis is the production of oxygen, which we measure with great precision as a proxy for the amount of carbon that has been fixed into organic matter. The remaining (non-photosynthetic) members of this microbial party are not particularly polite dinner guests and have a tendency to exploit the kindness of our fearless photosynthetic community by eating the food that the phytoplankton have dutifully prepared, namely themselves (phytoplankton bodies) along with their subsequent secretion of dissolved organic matter (zooplankton are quite the sloppy eaters). We measure this microscopic massacre in the form of oxygen consumption, because, like us, these microbial heterotrophs need oxygen and organic matter that phytoplankton produce in order to live. Collectively, the ocean acts as one breathing organism as this process plays out, silently taking in copious amounts of carbon dioxide from the atmosphere and giving us oxygen that we breathe. This balance (or lack thereof) of carbon/oxygen uptake versus production lends us insight into the overall health or metabolic status of an ecosystem, in a way similar to taking the pulse of your body.

The Various light levels of the photosynthetron simulate different light conditions through the day, and the subsequent oxygen production/consumption is measured using optical sensors. SOI/ Vandermeulen

Act 3: Some telescopic insights into microscopic processes

One of the more confounding elements of studying oceanography is dealing with the fact that many measurements only tell us something about one very specific time and place in a very large and dynamic ocean. So, in addition to these experiments, we are monitoring the “color” of the ocean with continuous underway measurements of the reflectance of sunlight from the water. As sunlight hits the ocean, phytoplankton are capturing some of this light for photosynthesis, and they imperceptibly change the color of the water as light scatters back from the sea. Out in this near-barren desert of photosynthetic activity, we use a very precise radiometric measurement of over 100 wavelengths across the ultraviolet/visible spectrum to detect these subtle changes. As a NASA scientist, my other research life consists of using data from ocean-observing satellites that monitor changes in the color of the ocean over the entire globe every day. By understanding more about the link between biological activity that I’m measuring in the lab, the types of phytoplankton in the water, and how this changes the color of the ocean, we can refine how we monitor these processes from space, and thus increase our understanding of carbon cycle dynamics on a global scale. Just to re-iterate, we are literally monitoring the activity of microscopic organisms that are too small to see with the naked eye with a telescope orbiting our planet at over 15,000 mph to study climate scale processes. I think that’s pretty neat.

Act 4: Some microscopic insights into life, the universe, and everything

It’s been a long day, so I am going to wind down, grab my guitar, and serenade the sunset. They say if you sing to plants, they grow better, so there is some scientific merit to this ritual, mind you. Incidentally, our artist-at-sea, Kirsten, has inspired me through one of her onboard art + science seminars to try and take a more careful and purposeful look at the world around me. I will temporarily suspend the thought of Rayleigh scattering and radiative transfer equations as I watch the sun’s rays extend across the horizon. For now, I’ll just listen and observe.

NAAMES-II Expedition: June 5, 2016

June 8th, 2016 by Kristina Mojica

I have the uncanny privilege of penning this blog on the very day that we return to terra firma. In other words, we’re finally back on land and you expect me to write about the cruise?!?  It is true that most everyone’s thoughts are bent toward home and whatever awaits them there (kids, family, friends, pets, etc.) and I’m certainly no different. Nevertheless, I will take this opportunity to reflect on few things that I will in fact, miss from our trusty mobile home over the last month, the R/V Atlantis. Indeed, there are many advantages to life at sea. Mariners have known this ever since, but there are subtle, more modern differences as well. For instance, it has been 26 days since I last handled money, keys, or a wallet. While these small things are necessary items to successfully navigate everyday life back home, they have no real value out here. No moments of “Where are my keys?” or “I forgot my wallet!” Our currency consists of good deeds and efforts to make the work/living space as enjoyable as possible. It’s easy to prosper when that is your measuring stick.

"How do these things work again?"

“How do these things work again?”

And don’t even get me started about cell phones. Being at sea is a bit of a throwback to a time (not that long ago), when not everyone had their faces buried in a personal device. Yes, we rely on all sorts of technology while out here, but there something not so offensive about it….but I digress … Generally speaking, being insulated from the continuous onslaught of [mostly bad] news is also a blessing in disguise. For better or worse, I haven’t thought about this year’s presidential election once this past month (insert your favorite presidential candidate joke here). That is not to say that I don’t care, or more importantly, that it has no bearing on our ability to be here, but there is more than a kernel of truth in the old saying, “Ignorance is bliss”. Overall, there is just less to worry about out here. For us , the passengers, that is. The captain, mates, engineers, and seamen worry about our course and our safety. Our food and shelter is well cared for by the stewards department. Life is easy……sort of…..

Now, in contrast to the enjoyment of getting home, there is actually a lot to worry about work-wise once we’re back!! Despite working 14+ hours per day, 7 days per week while on the cruise, we return to work having been out of the office for a month! There’s a lot to catch up on. Add to that all the samples that are being shipped home for further analyses and follow-up work that we have generated as a result of the cruise. Of course, then there is the planning for the next expedition in 18 months, the papers that need to get written, meetings, etc.……Well, it once again makes this life at sea seem so bad after all …..So, thanks for reading, but I had better get to work!……Wait, where’s my wallet?…

Written by Toby Westberry

NAAMES-II Expedition: May 31, 2016

June 1st, 2016 by Kristina Mojica

PMEL Aerosol Group

Aerosols are another name for particulate matter in the atmosphere. Aerosols are important because in clear skies they can scatter sunlight back to space can act to help cool the planet. Aerosols are also important because they can act as a site for water to condense on and form cloud particles. Particles that water can condense on are called Cloud Condensation Nuclei, CCN. In fact the concentration of CCN can greatly affect the optical properties of the cloud that is formed when air is lifted and cooled. If there are a small number of CCN the resulting cloud will have a small number of large droplets. If there are a much larger number of CCN the resulting cloud will have a large number of small droplets. Even though the liquid water concentration in both clouds is the same, the cloud with the large number of small droplets will be much whiter, and reflect more sunlight then the cloud with the small number of large droplets.

It is believed that Aerosols can thus counteract some of the present and future greenhouse warming, and it is vital to understand the processes that create and modify aerosols in the marine atmosphere.

Our group from NOAA-PMEL and the University of Washington JISAO is making measurements of the physical, chemical and optical properties of the aerosols in the marine atmosphere.

The following is a photo tour of some of our instrumentation

Our aerosol inlet at the top of one of our lab-vans.  Our inlet is aerodynamically designed and has a computer controlled motor to keep the inlet pointed into the wind so the large particles do not impact on the side of the inlet.

Our aerosol inlet at the top of one of our lab-vans. Our inlet is aerodynamically designed and has a computer controlled motor to keep the inlet pointed into the wind so the large particles do not impact on the side of the inlet. Photo: Jim Johnson

This is the inside of one of our aerosol vans with assorted particle counters, and several devices to measure the particle size spectrum.   Photo: Jim Johnson

This is the inside of one of our aerosol vans with assorted particle counters, and several devices to measure the particle size spectrum. Photo: Jim Johnson

Our Cloud Condensation Nuclei Counter, CCNC, an instrument that takes sample air and raises the humidity to various levels that are just above the condensation point, then it measures concentration of water drops that are formed. Photo: Jim Johnson

Our Cloud Condensation Nuclei Counter, CCNC, an instrument that takes sample air and raises the humidity to various levels that are just above the condensation point, then it measures concentration of water drops that are formed. Photo: Jim Johnson

Another activity is to help with the launch of the weather balloons. The radiosonde attached to the balloon measures temperature, relative humidity and pressure. The radiosonde also receives GPS to track its motion as it ascends, so that a vertical profile of the horizontal winds can also be derived.

Preparing the radiosonde for launch. Photo: Jim Johnson

Preparing the radiosonde for launch. Photo: Jim Johnson

A weather balloon is filled with helium and the radiosonde is attached. Photo: Jim Johnson

A weather balloon is filled with helium and the radiosonde is attached. Photo: Jim Johnson

The balloon and radiosonde are walked to the back of the ship's fantail and released.  As the package rises it sends back the data by a radio link to make a vertical profile of temperature, humidity and winds. Photo: Jim Johnson

The balloon and radiosonde are walked to the back of the ship’s fantail and released. As the package rises it sends back the data by a radio link to make a vertical profile of temperature, humidity and winds. Photo: Jim Johnson

Written by Jim Johnson

NAAMES-II Expedition: May 30, 2016

May 31st, 2016 by Kristina Mojica

THE BLOW
So far we have been blessed with calm seas and fair winds. We arrived yesterday at our last station, somewhat rested after a 24 hours transit and ready for the grand finale. Neptune had another plan. Half way through the station the winds picked up very quickly, reaching 50 knots with gusts of 60 and the ocean began to build up. The aerosol team got very excited. For oceanographers, the prospect of completing the station looked gloomy. At 11:00 PM I went to the Alvin hanger, the official gathering spot of the nocturnal NCC (NAAMES Coffee Club). All the ‘regulars’ were there with the coffee mugs and it was clear that there would be no overboard deployment of instruments at night (or the day after) so we just sat for a long time, on a pile of crates (aka the bleacher), watching the waves flooding the stern and admiring the power of the ocean. A visit to the bridge provided even more dramatic views of the developing storm.

The nocturnal NCC

The nocturnal NCC

Images from 'the blow' experienced on-board the Atlantis. Photo: Lee Karp-Boss (top left), Nils Haentjens  (top right and bottom left), : Cleo Davie-Martin (bottom right)

Images from ‘the blow’ experienced on-board the Atlantis. Photo: Lee Karp-Boss (top left), Nils Haentjens (top right and bottom left), : Cleo Davie-Martin
(bottom right)

A wave splashing on deck of the RV Atlantis during 'the blow'. Photo: : Cleo Davie-Martin

A wave splashing on deck of the RV Atlantis during ‘the blow’. Photo: : Cleo Davie-Martin

Twelve hours later, a fully developed sea with 30 ft. waves. Two of the incubators on the fantail got damaged and other items shifted place or were lost for good. No one is allowed on deck. We are rocking and rolling but everyone is still smiling. Lunch required good motor skills and coordination, eating a hamburger while keeping the plate and cup from flying across the table. The lab spaces that normally hustle and bustle with activity are fairly quit today and people take the opportunity to get much needed sleep, process data, relax and play cards. For our team (and the aerosol group) sampling continues through the inline system (described in an earlier blog), pumping seawater into the lab and measuring optical properties, abundances and species composition of plankton. Tomorrow we will begin our journey back to WHOI. Some high seas are still expected but nothing like what we have experienced today.

Written by Lee Karp-Boss (member of the nocturnal NCC)

Notes from the Field