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A Swirling Stew of Trichodesmium

Wide Ocean, Tiny Creatures - Mon, 03/09/2015 - 09:43
A large population of Trichodesmium, known as a bloom, seen from the side of the R/V L'Atalante.

A large population of Trichodesmium, known as a bloom, seen from the side of the R/V L’Atalante.

Greetings from the center of that eddy I mentioned in my last post! We’ve been here for five days so far, but tomorrow we are finally moving on. As far as eddies go, this is a tiny one, only 15 kilometers, but larger eddies can be 100 to 200 kilometers in diameter. The eddy we’re in is anticyclonic, which means it has a warm water core and rotates counterclockwise, albeit imperceptibly from my point of view on the deck of L’Atalante. Here in the center, the water seems smooth as a pond.

The physical oceanographers on board were excited about studying the turbulence throughout the water column here in the eddy center. I share in their excitement because studies have shown that Trichodesmium abundance is correlated with anticyclonic eddies.

Cruising toward the eddy, I pictured a swirling stew of Trichodesmium, an ephemeral phenomenon that would dissipate, sweeping away clues about how these transient physical features influence microbial physiology and biogeochemistry. We found a ton of Tricho out here, but it wasn’t necessarily soupy until today. At some point between this morning when Andi and I went out with the net tow and this afternoon, the surface water around us became dense with mats of Trichodesmium.

As the ship maneuvered to maintain position, the bow sliced through the mats, sending tendrils of green curling away in our wake. I watched the green swirl with the blue water and pondered what all that Tricho was doing up at the surface. It’s inhospitable for any organism floating out there in the direct sunlight. I can attest to this: the five minutes I stood on the deck taking pictures of the Trichodesmium were enough to give me a sunburn.

I’ve heard that floating mats of Trichodesmium is the sign of a crashed bloom. So, what changed suddenly changed? Some limiting nutrient could have been depleted to critically low levels, or a virus could have decimated the Trichodesmium population around us. Or the physics of the eddy could have forced the colonies to the surface. Whatever happened, it likely altered the physiology of the Trichodesmium, and consequently the environment.

Colonies of Trichodesmium (also known as"puffs") collected from the South Pacific

Colonies of Trichodesmium (also known as “puffs”) collected from the South Pacific.

Retreating back into the shade, I realized that our time in the eddy could encompass a narrative of a Trichodesmium bloom. Each day I’ve taken in situ samples of Trichodesmium, meticulously cleaned the colonies of any stowaway microbes. Back in the Dyhrman Lab at Lamont-Doherty Earth Observatory, I will extract the RNA from these samples and look at how gene expression of Trichodesmium changed over the course of our stay in this eddy. Hopefully this will help get a step me closer towards answering the questions above.

Now, however, with the day’s experiments finished, samples safely stored and bottles washed, I’m looking forward to a mini break from 24/7 science as we steam to the next station. As I was frantically running up to the incubators to harvest the last experiment, I noticed the crew building something on the front deck of the ship. Later, I enquired about this mystery project: it’s a hot tub.

Au revoir from 19 degrees south, 164 degrees east!

Follow @kylefrischkorn and the @DyhrmanLab on Twitter for more frequent updates from the OUTPACE cruise.

Trichodesmium is Everywhere!

Wide Ocean, Tiny Creatures - Thu, 03/05/2015 - 20:26

We have completed the first two stations of the OUTPACE cruise and we are steaming to Station 3. By noon tomorrow we should be in the center of an eddy that our colleagues back on dry land have used satellite data to identify. Apparently they are detecting very high chlorophyll in the center of the eddy, which should make for good sampling.

Trichodesmium is everywhere out here. I just looked out of the porthole next to the desk in my cabin, and a giant bloom was floating by on the surface of the waves. Filaments of the cyanobacterium Trichodesmium clump together and form little colonies about the size of an eyelash. When we’re on station, Andreas and I fish for colonies using a special net that we tow up and down through the water column to concentrate thousands of liters of water’s worth of biomass. It’s grueling work—I have blisters on my hands and my biceps are sore…but it makes me feel like I’m earning the five-course French meals served on this ship.

Once we’ve fished for colonies, Andi and I individually pluck out Trichodesmium colonies from amidst the other organisms that were concentrated during the tow and rinse them twice in sterile filtered seawater to remove all but the closely associated symbiotic microbes that colonize Trichodesmium. This is grueling work too, but for a very different reason than towing a net. Imagine using a tiny pipette to grab things the size of eyelashes out of water while rocking side to side on a moving ship in 90 degree Fahrenheit weather. Come visit me in the lab at Lamont and I’ll let you try and pick some Tricho—it’s hard even when the ground isn’t moving beneath you.

Sunset over the South Pacific ocean at the end of Station One.

Sunset over the South Pacific ocean at the end of Station 1.

So far, we’ve set up experiments to look at how nutrient uptake changes when we add different microbial communication molecules to the Trichodesmium colonies we’ve plucked, and of course we’ve taken samples so I can look at the molecular underpinnings of these physiological changes. The first two stations have been pretty successful. The ship is stable enough that I haven’t had to take any Dramamine, and really, the food is incredible. I woke up to sample at 5 a.m. yesterday, buoyed by the smell of freshly baked croissants.

Now that we’ve got our sea legs, I think we’re ready for the big kahuna, so bring on whatever’s happening in that eddy!

Follow @kylefrischkorn and the @DyhrmanLab on Twitter for more frequent updates from the OUTPACE cruise.

Trichodesmium is Everywhere!

Wide Ocean, Tiny Creatures - Thu, 03/05/2015 - 18:00

So far, we have completed the first two stations of the OUTPACE cruise and we are steaming to Station 3. By noon tomorrow we should be in the center of an eddy that our colleagues back on dry land have used satellite data to identify. Apparently they are detecting very high chlorophyll in the center of the eddy, which should make for good sampling. 

Trichodesmium is everywhere out here. I just looked out of the porthole next to the desk in my cabin, and a giant bloom was floating by on the surface of the waves. Filaments of the cyanobacterium Trichodesmium clump together and form little colonies about the size of an eyelash. When we’re on station, Andreas and I fish for colonies using a special net that we tow up and down through the water column to concentrate thousands of liters of water’s worth of biomass. It’s grueling work—I have blisters on my hands and my biceps are sore…but it makes me feel like I’m earning the five-course French meals served on this ship.

Once we’ve fished for colonies, Andi and I individually pluck out Trichodesmium colonies from amidst the other organisms that were concentrated during the tow and rinse them twice in sterile filtered seawater to remove all but the closely associated symbiotic microbes that colonize Trichodesmium. This is grueling work too, but for a very different reason than towing a net. Imagine using a tiny pipette to grab things the size of eyelashes out of water while rocking side to side on a moving ship in 90 degree Fahrenheit weather. Come visit me in the lab at Lamont and I’ll let you try and pick some Tricho—it’s hard even when the ground isn’t moving beneath you.

Sunset over the South Pacific ocean at the end of Station One.

Sunset over the South Pacific ocean at the end of Station One.

So far, we’ve set up experiments to look at how nutrient uptake changes when we add different microbial communication molecules to the Trichodesmium colonies we’ve plucked, and of course we’ve taken samples so I can look at the molecular underpinnings of these physiological changes. The first two stations have been pretty successful. The ship is stable enough that I haven’t had to take any Dramamine, and really, the food is incredible. I woke up to sample at 5 a.m. yesterday, buoyed by the smell of freshly baked croissants.

Now that we’ve got our sea legs, I think we’re ready for the big kahuna, so bring on whatever’s happening in that eddy!

Follow @kylefrischkorn and the @DyhrmanLab on Twitter for more frequent updates from the OUTPACE cruise.

Jawbone of Early Human Puts Evolution in a Whole New Light - LA Times

Featured News - Thu, 03/05/2015 - 12:00
"It's as if we were putting together this gigantic, multidimensional puzzle," DeMenocal said. "There was a big missing piece we couldn't find anywhere in the box. Now, we've magically found it."

OUTPACE Cruise: Setting Sail

Wide Ocean, Tiny Creatures - Tue, 03/03/2015 - 11:28

The OUTPACE 2015 cruise has set sail on February 20! We left port in Nouméa at 8:30 a.m. last Friday morning. I lost sight of land around 10 a.m. or so, and I won’t see it again until we return to port in Papeete, Tahiti on April 3.

Filling dewar flasks with liquid nitrogen at a nickel mine in Noumea in preparation for the OUTPACE research cruise.

Filling dewar flasks with liquid nitrogen at a nickel mine in Noumea in preparation for the OUTPACE research cruise.

Preparations before departure were so hectic that I didn’t even take a moment to appreciate the last time my feet left dry land as I climbed the gangway onto the ship. I spent the majority of my last two days in New Caledonia in a nickel mine north of Nouméa with a man from Vanuatu named Lulu. One of the byproducts of nickel mining is liquid nitrogen, the ultra-cold substance used to make ice cream, slow down the Terminator, and most importantly, preserve our samples until we can analyze them back at our labs on land. There are around 30 scientists on board, and with the exception of the physical oceanographers, everyone needs liquid nitrogen. I am very thankful for Lulu, he was my escort between ship and mine as I filled dewar flask after dewar flask of liquid nitrogen, he was my translator when I thanked the miners for their time, and he very kindly obliged when I suggested that perhaps he could drive slower because the dewars are fragile and his truck had no seat belts.

Having a stockpile of liquid nitrogen is especially critical for the samples I am planning to take during the OUTPACE cruise. I mentioned before that we are interested in how communication between Trichodesmium and other bacteria influences physiology and biogeochemistry. In the Dyhrman Lab at Lamont-Doherty Earth Observatory, we go about answering these questions in part by looking at what genes these microbes turn on or off under different conditions. To do this, we sequence the RNA, or the messenger molecules that act as the intermediary between the genome and the proteins that do the work in an organism. This data provides us with a snapshot in time of every single thing the cell was doing. The unique challenge is that RNA turns over incredibly rapidly. Shortly after fishing a Trichodesmium colony out of the ocean, their RNA profile could change from representing their in situ physiology to representing the response to sudden changes in temperature, light levels or the other stresses that accompany getting jostled around in a pipette by a graduate student trying to maintain balance on a moving boat. From ocean to liquid nitrogen, I have around five minutes before the samples are ruined.

It’ll be a day and a half until I take the first sample of the cruise, however. We’re currently steaming northwest from the southernmost point of New Caledonia to our first sampling station. For now we are rehashing plans, looking at satellite data to figure out where the eddies are and the patterns in sea surface chlorophyll, and finally ensuring every single thing in the lab is secured now that there is the pitch and roll of a cruising ship.

Follow @kylefrischkorn and the @DyhrmanLab on Twitter for more frequent updates from the OUTPACE cruise

Climate Change Helped Fuel The Syrian Conflict, New Paper Finds - Huffington Post

Featured News - Mon, 03/02/2015 - 12:00
Quotes Lamont scientist Richard Seager.

Study Links Syria Conflict to Drought Caused By Climate Change - New York Times

Featured News - Mon, 03/02/2015 - 12:00
Quotes Lamont scientist Richard Seager.

California’s terrifying climate forecast: It could face droughts nearly every year - Washington Post

Featured News - Mon, 03/02/2015 - 12:00
Cites research by Lamont scientists Jason Smerdon and Ben Cook.

Study: Human-caused global warming behind Calif. drought - USA Today

Featured News - Mon, 03/02/2015 - 12:00
Quotes Lamont scientist Richard Seager.

Pakistan's Water Shortage Creates Dangerous Agriculture Conditions - CCTV-America

Featured News - Sat, 02/28/2015 - 12:00
A Pakistan Minister has warned that scarcity of water is a major issue looming in the country and efforts need to be made to resolve it right away. Pakistan is already facing a massive power and...

The Most Astonishing Thing

Geopoetry - Fri, 02/27/2015 - 09:00
A super-massive black hole, roughly 12 billion times as massive as our sun, has been discovered at the center of a bright quasar. The light reaching us now from that distant location has been traveling for billions of years, and thus offers a glimpse into the earliest stages of the universe.

A super-massive black hole, roughly 12 billion times as massive as our sun, has been discovered at the center of a bright quasar. The light reaching us now from that distant location has been traveling for billions of years, and thus offers a glimpse into the earliest stages of the universe. Image: NASA/JPL-Caltech

 

The most astonishing thing about the universe, in my eyes,

Is not merely its gargantuan, unfathomable size,

But the way its vastness ferries gorgeous, primordial light,

So that as we look up into the night,

The farther afield our gaze penetrates, the higher we climb,

The farther we can see back in time.

Like ancient missives carefully tucked into a bottle,

Flashes of history race towards us full-throttle,

At the speed of light traversing a fabric expanding,

These waves touch our shores, and fuel our understanding

Of quasars and black holes, the light and the dark,

The Very Beginning, the bright cosmic spark

From which all this sprang – upon us, the story rains:

Of how we arose with star stuff in our veins.

 

_________________________________________________________

Further reading:

Gigantic Black Hole Discovered from the Dawn of Time, National Geographic

An ultraluminous quasar with a twelve-billion-solar-mass black hole at redshift 6.30, Wu et al. (2015) Nature

This is one in a series of poems written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory and the Department of Marine and Coastal Sciences at Rutgers University.

3 Reasons to Give a Damn About the Deep Sea - Environment Guru

Featured News - Tue, 02/24/2015 - 12:00
In a new study published in the journal Geophysical Research Letters, Columbia University marine geophysicist Maya Tolstoy reports fluctuations in eruption activity that correlate with changes in sea...

Global Warming Likes its Chicken Fried - Red Orbit

Featured News - Mon, 02/23/2015 - 12:00
Quotes Jason E. Smerdon of Columbia University’s Lamont-Doherty Earth Observatory.

Unexpected role of climate in bringing plague to medieval Europe - CBS News

Featured News - Mon, 02/23/2015 - 12:00
Quotes Lamont scientist Brendan Buckley.

A Thirsty, Violent World - The New Yorker

Featured News - Mon, 02/23/2015 - 12:00
Growing hunger and the struggle to find clean water for billions of people are clearly connected. Quotes Lamont scientist Jason Smerdon.

Did Dark Matter Kill the Dinosaurs? - Science

Featured News - Sat, 02/21/2015 - 12:00
Quotes Dennis Kent, a geophysicist at the Lamont-Doherty Earth Observatory.

Eco-Drones Aid Researchers in Fight to Save the Environment - NBC News

Featured News - Fri, 02/20/2015 - 12:00
At Lamont Doherty Earth Observatory, Chris Zappa is planning his next mission to monitor ice melt in the Arctic..

Mysterious Demise of an Australian Thunder Bird

Geopoetry - Fri, 02/20/2015 - 08:00
 Ann Musser @ Australian Museum.

Genyornis newtoni, one of the great “thunder birds” of Australia, went extinct about 50 thousand years ago, for reasons that are still not clear. Image: Ann Musser @ Australian Museum.

 

Here, mankind and death coincide,

But everyone’s still mystified …

Geologists find

This thunder bird’s kind

Were lost as Australia dried.

 

_________________________________________________________

Further reading:

Hydrological transformation coincided with megafaunal extinction in central Australia, Cohen et al. (2015) Geology

Drying lakes linked to extinctions, Nature

 

This is one in a series of poems written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory and the Department of Marine and Coastal Sciences at Rutgers University.

Bonjour de Nouméa!

Wide Ocean, Tiny Creatures - Wed, 02/18/2015 - 10:46

Scientists from research institutions around the world are participating in a research expedition aboard the R/V L ‘Atalante to study how microorganisms in the South Pacific Ocean influence the carbon cycle. Lamont-Doherty Earth Observatory graduate student Kyle Frischkorn is among them; his goal is to assess how the microorganism Trichodesmium, and other microbes, interact and the resulting physiological and biogeochemical impacts these processes have on marine ecosystems. This is the first in a series of posts in which Kyle shares what it’s like to do research at sea.

The research vessel L'Atalante in port in New Caledonia.

The research vessel L’Atalante in port in New Caledonia.

I am reporting from the shores of New Caledonia. I am just about as far away from my home in New York City as one can get—literally and metaphorically: New Caledonia is an island in the southern hemisphere, in the subtropical South Pacific, east of Australia. I am in the capital city, Nouméa, where palm trees lines streets that move at a leisurely, island pace. It’s also about 80 degrees Fahrenheit warmer than New York City right now, which is perhaps the most jarring difference of all.

Few have heard of New Caledonia, a French “special collectivity”. I hadn’t either, until I had to get a plane ticket here. During World War II this island served as the South Pacific headquarters of the US military. This was strategically important for the Allied forces during WWII, it had good infrastructure and developed roads. Additionally, the hospitality of the New Caledonians and the tropical amenities offered much needed respite for the soldiers. This is a snippet of what I learned at the Musée de la Seconde Guerre Mondiale, just one stop on my two-day exploration of the city before embarking on 45 days of non-stop science.

As luck would have it, on my way to the museum I rode the bus one stop too far—an easy mistake to make, the street signs are miniscule and in French, also the buses blast catchy, island-y remixes of American Top 40 songs so I was reluctant to disembark. After I stepped off the bus, I got my bearings and by chance found myself face to face with the research vessel L’Atalante, my home for the next 2 months.

Scientists from research institutions around the world are partaking in this expedition, the broad, overarching goal of which is to study how microorganisms in the South Pacific Ocean influence the carbon cycle. My specific project focuses on one particular microorganisms, a cyanobacterium called Trichodesmium. This microbe is important in the low nutrient, oligotrophic ocean because of their ability to take in and fix carbon dioxide through photosynthesis, and because they have the relatively rare ability to transform atmospheric nitrogen into a form that is a utilizable nutrient for other organisms in the ocean. These abilities make Trichodesmium colonies oases of biological activity in a desert-like ocean. My colleague Andreas Krupke, a post-doctoral researcher in the Van Mooy Lab at Woods Hole Oceanographic Institution, and I will be conducting a series of experiments on this transect from Nouméa, New Caledonia to Papeete, Tahiti to assess how other microbes and Trichodesmium interact and the resulting physiological and biogeochemical impacts these processes have.

Before we can get started on the science, however, the first mission is to unpack all of the gear I shipped from Lamont and re-assemble the Dyhrman Lab on L’Atalante. It’ll function just like our lab back on dry land, but all the equipment is literally tied, drilled or bungee corded to the benchtop… stay tuned!

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