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The Night Crew

The ENAM Seismic Experiment - Thu, 09/18/2014 - 22:06

September 18, 2014


No breaks from science! The Endeavor runs 24/7. When we are doing a line, we launch an OBS about every hour and a half from the ship. Here are some pictures on the night crew hard at work.
Pamela, Afshin, and Ernie assembling the Scripps OBS (Photo credit: Gary Linevich)Pamela, Afshin, Ernie, and Jenny assembling the Scripps OBS (Photo credit: Gary Linevich)Pamela and Jenny admiring their work (Photo credit: Gary Linkevich)Ernie and Afshin hooking up the OBS (photo credit: Gary Linkevich)Charlie operating the crane (Photo credit: Gary Linkevich)
Launching the OBS (Photo credit: Gary Linkevich)



See you Later, 

Kate Volk Aboard the R/V Endeavor









Ships crossing in broad daylight...

The ENAM Seismic Experiment - Thu, 09/18/2014 - 21:41
We passed the R/V Endeavor today as she steamed towards the southern end of this profile, where she will begin recovering OBS after the Langseth has passed over them, and the OBS have had a chance to record sound waves that turned deep below Earth's surface.  The Endeavor kept her distance to avoid disturbing all of the seismic gear that we are towing behind the Langseth!

Donna Shillington aboard the R/V Langseth
The R/V Endeavor on the horizon...

Seismic gear is deployed, and we are collecting data!

The ENAM Seismic Experiment - Thu, 09/18/2014 - 20:43

Yesterday, we deployed the seismic streamer and source of the R/V Langseth in record time - its no small feat to put 8 km (~5 miles) of streamer plus other equipment in the water behind a ship.  The streamer is filled with pressure sensors that will record sound waves that have traveled into the earth and bounced off geological features, like faults, sedimentary layers, and ancient lava flows.  It is unwound from a gigantic spool on the back of the vessel.  As it leaves the ship, we festoon it with a variety of important devices, like “birds” that control the depth of the streamer, “streamer recovery devices” that are air bags that deploy and float the streamer to the surface if it gets too deep, and acoustic navigation units that are used to help determine the position of the streamer beneath the ocean surface.  A tail buoy is located at the end of the streamer to help with positioning and alert others of the presence of the streamer, and a float is at the front to further control the depth of the streamer. We also check that everything is working while we’re putting it into the water. We deployed all 8 km in just 7 hours, and were rewarded with a rainbow and spectacular sunset as the last bits of equipment went off the stern.   We also deployed the seismic source, which consists of air guns suspended below four snake-like black floats.  Now that all the kit is in the water, we are happily collecting data. Its a very good moment when the seismic data begins to come in...

Donna Shillington aboard the R/V Langseth
The top of the streamer reels. We are unspooling seismic streamer from the reel on the right. (Photo: Jenna Hill)
Looking towards the stern across the streamer reel (Photo: Derek Sawyer)Matt, Sasha and Carlos attach a bird to the streamerThe streamer entering the water behind the ship with a bird
Kara fetches a bird to place on the streamerMatt and Robert monitor the deployment operation from the main lab.A rainbow hovers over Jenna and Ben with the final bit of streamer (Photo: Derek Sawyer)

Transit update and food for thought

The ENAM Seismic Experiment - Thu, 09/18/2014 - 16:26

September 18th, 2014
1625

I was awoken early this morning, after only a few hours of sleep, by some unknown portion of my subconscious and was struck by a thought concerning the unique nature of performing science at sea. The ocean, as a scientific laboratory, forms a constant connection with those who venture into it that is experienced by few, if any, terrestrial experimentalists. During my 12-hour watch, my mind is clearly engaged by the science that we are performing. When is the next instrument being deployed? What needs to be done to be ready for it? Will we survey this instrument once it rests on the seafloor? These are just a few examples of the many questions that cross not only my mind, but the minds of my peers as well. More interestingly, however, I also find that I am acutely aware of changes to my environment, which readily defy alterations in our scientific progress, even as I lay semi-conscious in my bunk. The temporal spacing between the response of the 12hz Echosounder pinging against the hull informs me of any relative change in depth from the last time I was awake. The direction and intensity of the ship’s sway can tell me about our heading and/or a change in weather conditions. A variation in the output frequency of the engine’s constant drone provides me with our current speed and suggests what kind of scientific activity the other watch might be performing one deck above my head. It the result of these types of observations that those aboard these floating beasts that operate 24-hours a day are constantly engaged in their environment, whether or not they desire to be. Anyways, perhaps this helps orient those who have never been to sea for an extended period or recalls reflection for those who have ventured out into the wild blue yonder previously, either way I felt it was an interesting thought worth sharing.

Currently, the R/V Endeavor is a little over halfway through its transit back to the end of Line 2. Along the way, we surveyed OBS Sites 210 and 211 to accurately locate each device on the seafloor which will assist with our recovery. Once we reach the eastern end of Line 2, before starting our recovery operations, we will perform a rosette test. However, the event that all the scientific party is looking forward to is passing by the R/V Langseth sometime early evening and waving ‘hello’ to our scientific comrades.

Till next time,
Dylan Meyer aboard the R/V Endeavor


One of the crew, Chris, noticed this awesome moth that landed on deck yesterday. A clear sign that we were close to shore (Photo Credit: Dylan Meyer)

After passing through a heavy squall, we were rewarded with a full rainbow! (Photo Credit: Dylan Meyer)

OBS Deployed

The ENAM Seismic Experiment - Wed, 09/17/2014 - 23:53

 September 17, 2014

We are moving right along with our OBS deployments. We have finished deploying along line 3 and line 2. The R/V Langseth is now on its way to start shooting line 2. Next we are heading back for the recovery of line 2 before starting to deploy at line 4. The seas have been fairly calm, making for easy deployments and smooth sailing!

Mark assembling the data logger (photo credit: Kate Volk)Mark and Gary assembling the OBS (photo credit: Kate Volk)
Dylan taking down numbers on the OBS (photo credit: Kate Volk)
Kate with assembled Scripps OBS (Photo credit: Dylan Meyer)Mark, Gary, and Kate hooking up the Scripps OBS for deployment (Photo credit: Dylan Meyer)

Kate holding the tag line (photo credit: Dylan Meyer)Scripps OBS being deployed (Photo credit: Dylan Meyer)
Rainbow! (Photo credit: Kate Volk)
See you later, 

Kate Volk aboard the R/V Endeavor 

The OBS is in the water!

The ENAM Seismic Experiment - Tue, 09/16/2014 - 21:58

September 16th, 2014
2142

At 0630 on September 15th, after a successful CHIRP survey, rosette test, and styrocast, our team released the first OBS, allowing it to fall 4100 meters to the seafloor. Our first deployment was of an OBS from WHOI, pictured below, and it was followed a couple hours later by an OBS instrument from SIO. This method was adopted to get the members of the watch acclimated to the process of preparing and launching each of these devices. Now, approximately 39 hours later, both watches have fallen into a rhythm, each person comprehending how to efficiently setup and deploy both types of instrument. As a result of our efforts, we are currently ahead of our original schedule! We are currently 16 instruments away from completing our first deployment campaign and are looking forward to beginning to recover our instruments for redeployment. Also, everyone on board to excited to hear that the R/V Langseth has left the dock early on the 16th and is in transit to begin their multi-channel seismic (MCS) surveys!

Until next time,
Dylan Meyer aboard the R/V Endeavor


I would like to thank science (and pressure) for helping us shrink 15 styrofoam cups to approximately a quarter of their original size! (Photo Credit: Dylan Meyer)


A WHOI OBS being prepared for deployment at night. The SIO OBS lays ready for later deployment just off to the left. (Photo Credit: Dylan Meyer)


An OBS from WHOI about to be released. (Photo Credit: Dylan Meyer)

A small rain squall on the horizon is a common occurrence out here. Personally, I find them very refreshing! (Photo Credit: Dylan Meyer)

Sunset on September, 16th. I swear this photo is unedited. (Photo Credit: Dylan Meyer)

The Langseth heads to sea

The ENAM Seismic Experiment - Tue, 09/16/2014 - 15:30

This morning, the R/V Langseth left port in Norfolk, passing saluting gantry cranes, container ships, and naval vessels on her way out to open waters.    The sun is shining and the seas are calm – perfect weather for adjusting to life at sea and getting our collective sea legs.  
The R/V Langseth tied up at Lambert Point port in NorfolkWe will steam for ~24 hours to the eastern edge of our study area, where we will deploy our sound source and an 8-km-long streamer filled with pressure sensors. Over the next 35 days, we hope to use this seismic equipment to image everything from the base of the crust and deep magmatic intrusions related to the breakup of Pangea and opening of the Atlantic ocean to recent, large landslides along the east coast.   We will report often!
Passing container ship...Cranes waving to us...
Air craft carriers in NorfolkMatt Hornbach and Derek Sawyer rocking lifejackets at the first Fire and Emergency DrillThe science party of MGL1408
Donna Shillington aboard the R/V Marcus Langseth

Salty Seismic Station Servicing in the Outer Banks

The ENAM Seismic Experiment - Mon, 09/15/2014 - 22:40

Over the last three days Celia and I (both geophysics graduate students at Columbia University – Lamont-Doherty Earth Observatory) have been servicing ENAM’s three land-based broadband seismometers that sit on the Outer Banks of North Carolina.  These seismometers, installed in May of this year, represent a critical extension of ENAM’s ocean work as they expand the project’s scientific footprint across the western expression of the Eastern North American Margin magnetic anomaly.  This feature is one of ENAM’s key scientific targets as it is believed to be intimately tied to the complex rifting history of the Atlantic Ocean. 
Map showing the locations of existing USArray seismic stations (white), ENAM offshore seismic stations (yellow), and ENAM onshore seismic stations (red).
For our part, the goals for this service run were simple: 1) Safely retrieve the previously recorded data from the seismometers and 2) Check to make sure the instruments have been and currently are running well.  After spending a few days working in the sun and sand we are cautiously happy to report that we were successful on both fronts! First let’s talk about data.  
Station CHPH located near Cape Hatteras Middle School.  The solar panel sits on the right and the computer and seismic instrument sit buried beneath the sand on the left.  Their location is marked by the line of logs.
These instruments were installed in May 2014 and have been sitting quietly, buried beneath the sand recording ground motions from distant earthquakes ever since.  Amongst the treasure trove of data that we retrieved from the instruments are gorgeous records of both the Mw 6.9 Chiapas, Mexico event and of the recent Mw 6.0 Napa Valley earthquake, just to name a few.  Scientists will utilize traces of events such like these recorded at these stations to image the subsurface along the North Carolina coast with the aim to reveal the tectonic and deformational history of the region. 

Seismic records from the recent Mw 6.0 Napa Valley earthquake (left) recorded on ENAM station FFMS (located at First Flight Middle School) and the Mw 6.9 Chiapas, Mexico earthquake (right) recorded on station CHPH (located at Cape Hatteras Middle School).
With the data safely retrieved and stored on backup hard drives, we next moved onto checking on the instruments themselves or as we call it, their “state of health” (SOH).  The term SOH includes a variety of checks including the temperature of the digitizer (the computer that interacts with the seismometer), the accuracy of the clock used to keep time for the seismometer, the voltages of the batteries that power the instrument and the computer, …  By looking at the SOH we make sure that the entire package from the instrument to the computer to the solar panel (used to charge the battery) is performing adequately and that all components are successfully interacting with each other.
Natalie (left) and Celia (right) stand proudly in front of recently serviced seismic stations ECHS (located at East Carteret High School) and FFMS (located at First Flight Middle School).
With the data collected and health of the stations verified, it’s time to leave the seismometers to collect data silently by themselves for another few months.  More students and scientists will come to check on them again and retrieve their records this winter.  With such an active and dynamic world around us, who knows what geophysical treasures will be hidden amongst the data that will be collected then!

- Natalie Accardo, Columbia University - LDEO

Rosette Test

The ENAM Seismic Experiment - Mon, 09/15/2014 - 22:36

 September 15, 2014

Testing one, two, three! We successfully completed a Rosette test of the Scripps acoustic transducers at 4000 meters water depth. We wanted to be sure we could talk to the ocean bottom seismometers once deployed to the bottom of the Atlantic where the pressure is around 40 MPa and the temperature at about 4 °C. The test went smoothly, and now we are ready to deploy! While we were at it, we had a little fun with Styrofoam cups sending them down as well with messages and pictures making styrocasts.

Recovery from the Rosette test (photo credit: Gary Linkevich)
See you later,

Kate Volk aboard the R/V Endeavor 

Survey

The ENAM Seismic Experiment - Sun, 09/14/2014 - 21:48
 
September 14, 2014

Science! At about 20:30 Eastern Time on September 13 we reached our first survey site off the coast of Virginia. While we’re excited to start deploying ocean bottom seismometers, we know that there might be some coral in the area. We don’t want to disturb any wildlife and therefore want to avoid placing an ocean bottom seismometer on any coral. We used 3.5 KHz sound waves to penetrate the subsurface and see what the seafloor looked like in order to find a safe place for the OBS. We surveyed the desired area of deployment and 500 meters in any direction from that location. Overall we surveyed 3 separate locations finishing up about three in morning. 


The science party discussing the recording of the survey. (Photo Credit: Gary Linkevich)
Kate watching the response from the 3.5 KHz chirp. (Photo Credit: Gary Linkevich)Gary, Brandon and Harm looking at the record from the 3.5 KHz chirp survey 

R/V Endeavor Cruise Summary

The ENAM Seismic Experiment - Fri, 09/12/2014 - 18:24
September 12, 2014
1547

It’s a beautiful, sunny day in North Kingstown, RI and the R/V Endeavor bustled with activity as we made the final preparations for our 38-hour transit to Cape Hatteras.  The past two days have been a blur of science meetings, last minute purchases and preparations, and forced suppression of my excitement to be onboard another research cruise. I now stand on the observation deck above the bridge, calmed by the brisk sea breeze rushing through my hair, ready for the tasks required of me in the month to come.

The R/V Endeavor at dock from astern. The OBSs have been loaded onto the fantail. (Photo Credit: Dylan Meyer)Initial science party meeting while still at the dock. (Photo Credit: Dylan Meyer)On the observation deck after getting under way. (Photo Credit: Jennifer Harding)Okay, enough of the fluffy mumbo-jumbo. Let’s get to the good stuff. For those of you who haven’t yet read through the information on the Eastern North American Margin Community Seismic Experiment (ENAM CSE), may we never have to write out that acronym in full again, here’s a summary of our research goals on the R/V Endeavor. Over the next 32 days at sea (or less, if things go well), we have four main tasks:

          -    Perform a survey of the seafloor near three drop sites that are within an essential fish habitat - habitat area of particular concern (EFH-HAPC) off Cape Hatteras to assure proper placement of our equipment.
          -    Test the acoustic release mechanisms for the Ocean Bottom Seismometer (OBS) devices from Scripps Institution of Oceanography (SIO) and the Woods Hole Oceanographic Institution (WHOI), to assure that we can release the OBSs from the seafloor during the recovery process.
          -    Deploy and recover each of the 47 OBSs twice along the four multi-channel seismic (MCS) lines that will be shot by the R/V Langseth.
          -    Perform all the above operations in an efficient and safe manner.

The figure below shows the deployment stations for each of the OBSs and the MCS lines that will be run on the R/V Langseth after deployment.

Bathymetric/topographic map of the region around Cape Hatteras with MCS lines drawn in blue and OBS deployment stations as pink dots
The expanse of this experiment is absolutely incredible, and I highly suggest that you visit the “About” portion of this blog site as well as the GeoPrisms website:

http://www.geoprisms.org/enam.html

for additional information on the broader scientific goals of the ENAM CSE as well as specifics about the other branches of the experimental plan (MCS array, terrestrial seismic, long-period OBS).

Our scientific party consists of twelve people (2 research scientists, 6 graduate students, and 4 OBS technicians) from institutions spread across the US:

Harm van Avendonk – UT Austin Institute for Geophysics      Research Scientist
Brandon Dugan – Rice University Dept. of Earth Science        Research Scientist
Afshin Aghayan – Oklahoma State University                          Graduate Student
Jennifer Harding – UT Austin Institute for Geophysics            Graduate Student
Pamela Moyer – University of New Hampshire                        Graduate Student
Kathryn Volk – University of Michigan                                     Graduate Student
Dylan Meyer – UT Austin Institute for Geophysics                  Graduate Student
Gary Linkevich – Rice University Dept. of Earth Science        Graduate Student
Ernie Aaron – Scripps Institute of Oceanography                      OBS Technician
Peter Lemmond – Woods Hole Oceanographic Institute           OBS Technician
Mark Gibaud – Scripps Institute of Oceanography                    OBS Technician
Dave Dubois – Woods Hole Oceanographic Institute                OBS Technician

Research scientists and graduate students of the scientific party aboard the R/V Endeavor. From left to right - Pamela Moyer, Jennifer Harding, Afshin Aghayan, Dylan Meyer, Kathryn Volk, Brandon Dugan, Harm van Avendonk, and Gary Linkevich. (Photo Credit: Gary Linkevich) The scientific party (partial group photo above), assisted by the magnificent crew of the R/V Endeavor, will hopefully start our OBS deployment by Sept. 16th on lines 2 and 3, completing enough of the deployments on Line 2 such that the R/V Langseth can begin shooting as soon as they are on station and their equipment is deployed. From that point, we will recover all the OBSs and redeploy them along lines 1, 4a, and 4b in time for the R/V Langseth to begin shooting those MCS lines sometime on Sept. 30th. The OBSs will then be recovered and the R/V Endeavour will steam back to Quonset Point, arriving some time on or before Oct. 13th (knock on wood).

Before any science could commence, however, we all participated in a mandatory safety lecture and ship orientation. We tried out the “Gumby” Immersion Suits (pictured below), learned the essential emergency procedures, and were introduced to the myriad of safety equipment available on the R/V Endeavor. I have no doubts that the University of Rhode Island has provided us with a superbly safe working and living environment.

Testing out the "Gumby" suits during the safety orientation after getting under way. (Photo Credit: Gary Linkevich)
We’ve started our 12-hours on/off shift schedule now and I can already start to feel people falling into a routine. As we steam ahead with the wind from astern and following seas, the scientists on watch make preparations, calculations, and estimations aimed at improving our efficiency, while those off watch read, rest, and relax in anticipation of their next watch. The sun is shining, the seas are calm, and everyone is excited to get to work.

Till next time,
Dylan Meyer aboard the R/V Endeavor

Graceful, Tiny, Toothy Ancestors

Geopoetry - Fri, 09/12/2014 - 10:00
An artist's illustration of the tree-dwelling mammal Xianshou songae (by Zhao Chuang). The discovery of three new Jurassic species suggests that mammals evolved earlier and diversified more rapidly thank previously thought.

An artist’s illustration of the tree-dwelling mammal Xianshou songae (illustration by Zhao Chuang). The discovery of three new Jurassic species suggests that mammals evolved earlier and diversified more rapidly than previously thought.

 

With body spry, tail curly,

This mammal showed up early.

Did Xianshou squeak?

If bones could speak …

These might say “I’m squirrely!”

 

 

________________________________

Further reading:

Chisel-toothed beasts push back origin of mammals, National Geographic

Three new Jurassic euharamiyidan species reinforce early divergence of mammals, 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 Institute of Marine and Coastal Sciences at Rutgers University.

 

 

Dreadnoughtus

Geopoetry - Fri, 09/05/2014 - 08:00
 Jennifer Hall

An artist’s vision of how Dreadnoughtus schrani would have appeared. Credit: Jennifer Hall

 

If you, like me, are something of a paleo-romantic,

Swooning over dinosaurs both fearsome and gigantic,

Come feast your eyes on new reports the bone-hunters have brought us:

“Fearing nothing” means its name – the mighty beast Dreadnoughtus!

Seven times as heavy as Tyrannosaurus rex,

This gentle vegan creature boasted tons of muscle flex.

Patagonian earth under its massive feet would quake,

What a silhouette at dawn a family would make!

Even ‘mongst Titanosaurids, this one breaks the ceiling,

A shoulder blade as tall as I am – God, it sets me reeling.

On top of that, when this one died, it wasn’t yet mature …

How much more would it have grown? We can not be quite sure.

3D-scanning, high-tech models try to help us see one,

But why were creatures bigger then? What was it like to be one?

Children are the best at this, working on all fours,

Today, I think I’ll try it too: fear nothing, shake the floors!

 

____________________________________________

Further reading:

Giant dinosaur unearthed in Argentina, Science SHOT

A Gigantic, Exceptionally Complete Titanosaurian Sauropod Dinosaur from Southern Patagonia, Argentina, Nature

New “Dreadnought” Dinosaur Most Complete Specimen of a Giant, Scientific American

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 Institute of Marine and Coastal Sciences at Rutgers University.

Erosion, Then Explosion

Geopoetry - Fri, 08/29/2014 - 10:00
 Peters & Gaines, Nature, 2012

Illustration: Peters & Gaines, Nature, 2012

When viewing The Great Unconformity,
The result of a vast denudation,
One feels a new sense of enormity …
And above it lie critters crustacean!
Life during this wild explosion,
For armor, developed affinity.
Whence the new ions? Erosion!
Gooey life — meet alkalinity!

______________________________

Further reading:

Formation of the “Great Unconformity” as a trigger for the Cambrian explosion, Shanan E. Peters & Robert R. Gaines, Nature, 2012

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 Institute of Marine and Coastal Sciences at Rutgers University.

Faint Young Sun

Geopoetry - Fri, 08/22/2014 - 10:31
  Science online, J.F. Kasting

Image: Science online, J.F. Kasting

 

Through an ancient looking-glass,
Perhaps you’d see more H2 gas,
And if with denser gas collided,
Greater greenhouse warmth provided.
With faint young sun, would this suffice
To maintain water and not ice?
And when methanogens arrive?
This old debate is much alive.

_____________________________

Further reading:

Hydrogen-Nitrogen Greenhouse Warming in Earth’s Early Atmosphere, Wordsworth and Pierrehumbert, Science, 2013

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 Institute of Marine and Coastal Sciences at Rutgers University

Reflections of a Changing North

Greenland Thaw: Measuring Change - Fri, 08/22/2014 - 08:48
View from our small Poco 500 fishing boat as we skirted through the ice to collect samples. (Photo M. Turrin)

View from our small Poco 500 fishing boat as we skirted through the ice to collect samples. (Photo M. Turrin)

No one ever leaves the field the same way they entered it. Yes there is a new layer of mud on equipment, the expected wear and tear on your personal gear and your physical being, but that is not what I am referring to. I am acknowledging the intangible shift in perspective from a deepened understanding and a broadened vision that has been provided by the experience and beyond that the questions that drive the next field campaign.

Fishing and hunting is still the main livelihood of the Kullorsuaq community.  This type of small Poca 500 with a hand winch was what we found along the waterfront. (Photo M. Turrin)

Fishing and hunting is still the main livelihood of the Kullorsuaq community. This type of small Poca 500 with a hand winch was what we found along the waterfront. (Photo M. Turrin)

The end of any field campaign is bittersweet. The adrenaline rush of the data collection phase slows to a more normal rhythm of daily life. There is a change from an unwavering focus on the many details of the project with a hard push day after day to extract as much out of the field time as possible, to a position of intense reflection. Was the campaign a success? Were we able to accomplish what we had hoped? Did we come away with the data we wanted? What did we learn? Should this project be repeated? or adjusted? perhaps expanded?

Our Reflections –

The Kullorsuaq waterfront. (Photo M. Turrin)

The Kullorsuaq waterfront. (Photo M. Turrin)

Establishing Connections

Our fledgling partnership has shown there is both a willingness and an interest among the local Greenlandic to work with scientists in collecting measurements. There is an aptitude for working with the instruments and a desire by them for the collected data on temperatures at depth in their local fjords to build a broader understanding of their environment. Both the science team and the Greenlandic fishermen see this data as important to planning for the future. They are hopeful it will provide them insights to direct their fishing practices, which in this traditional community remains their main livelihood. We are hopeful it will provide evidence of processes driving change in the Greenland tidewater glaciers.

The Kullorsuaq fishermen are seen moving through the water at all times of the day and night. While we were there fishing conditions were difficult and fishermen were traveling well south to drop their lines. (Photo M. Turrin)

The Kullorsuaq fishermen are seen moving through the water at all times of the day and night. While we were there fishing conditions were difficult and fishermen were traveling well south to drop their lines. (Photo M. Turrin)

The Kullorsuaq fishermen have told and showed us that they will adapt to change in the north. We can help them adapt by providing them information that assists their choices and adjustments.

Deeper Understanding

Alison Glacier flows into Melville Bay just behind the rocky foot of Kullorsuaq (visible at the top of this photo). The bits of ice debris are loosely jumbled at this distance from the glacier front unlike at the mouth where they are densely packed. (Photo M. Turrin)

Alison Glacier flows into Melville Bay just behind the rocky foot of Kullorsuaq (visible at the top of this photo). The bits of ice debris are loosely jumbled at this distance from the glacier front unlike at the mouth where they are densely packed. (Photo M. Turrin)

When we arrived in this small community there were no water temperature measurements inside the fjords for this area of Greenland. We hoped to collect water column data that would tell us if this northwest corner of Greenland was being affected in the same way as other parts of Greenland, with warm Atlantic Water flowing in at depth. Bathymetry (bottom depth) measurements did not exist in this section of Greenland’s coastline and it turned out the area was much deeper than we had expected. When we planned the project the little data that is available showed depths of 400m, yet we lowered our instrument approximately 500 meters and only three of our casts reached bottom. The Kullorsuoq fishermen told us that in front of the glacier it is over twice this depth which they have learned from lowering their fishing line.

A preliminary look at one of our data casts shows the temperature dropping and then warming as the depth increases, a result of intersecting the different water masses. (Credit D. Porter)

A preliminary look at one of our data casts shows the temperature dropping and then warming as the depth increases, a result of intersecting the different water masses. (Credit D. Porter)

While we were not able to get data the full extent of the water column the measurements we collected confirmed that, as in other areas of Greenland, warm surface water (>4°C) is layered on top of colder fresh Polar Water (<-1.5°C), and below this, from about 200 m (700 ft.) and below, flows warmer Atlantic Water. As our equipment didn’t allow us to go the full water depth we don’t know how warm it gets, but we know it exceeded 1.7°C and was still rising at the depth of the cast. This warm deep water is affecting glaciers like Alison that sit in deep fjord troughs by melting the ice at the base of the glacier, causing weakening and retreat.

Moving Forward

Map of the series of casts completed in front of Alison Glacier and Hayes Glacier to the north. Red was day 1 of sampling, Green was day 2.  (Credit D. Porter)

Map of the series of casts completed in front of Alison Glacier and Hayes Glacier to the north. Red was day 1 of sampling, Green was day 2. (Credit D. Porter)

Our sampling plan was adjusted to deal with the ice conditions in the field. We had to shift our collection points to work around the mélange in front of glacier. We focused the first day (shown in red) on getting as close to the ice front as possible, collecting a ‘transect’ or line of measurements, and surveying the smaller channels. Day 2 (shown in green) we extended the transect from day 1, tested for pathways to the outer shelf, and tested one of Hayes Glacier (just north of Alison) outlets paths, and collected some repeat measurements from Day 1 to see how conditions vary with time and tides.

Moving through the water to collect more samples is done by boat for summer sampling, but the conditions will be very different in the winter when dog sledges will be needed. (Photo M. Turrin)

Moving through the water to collect more samples is done by boat for summer sampling, but the conditions will be very different in the winter when dog sledges will be needed. (Photo M. Turrin)

We have plenty of data to analyze but in the future collecting data in other seasons and locations would be beneficial. According to our Greenlandic partners getting winter measurements in Kullorsuaq is possible using their dog sledges to move the instrument. Early spring would offer interesting conditions as well. The local fishermen are anxious to continue to work with us, and we hope to be able to continue and build on this partnership.

It is always bittersweet to leave an area where you have built connections and learned so much.  (photo M. Turrin)

It is always bittersweet to leave an area where you have built connections and learned so much, but we look forward to more opportunity to work together. (photo M. Turrin)

Qujanoq (kwee-yan-ok) to our new Greenlandic friends – Thank you.

Project Information: Dave Porter and Margie Turrin were in northwest Greenland working with local community members to collect water column temperature profiles. The Leveraging Local Knowledgeproject will work with members of local Greenlandic communities to collect water measurements in the fjords. This will assist in determining if warming Atlantic Ocean water is circulating up through Baffin Bay where it enters the fjords to lap against the frozen glacier footholds, causing them to loosen their hold on the rock below. Alison Glacier (74.37N and 56.08W) is selected as the project focus. Emptying into Melville Bay to the east of Kullorsuaq Island and has been undergoing dramatic change over the last decade.

The project is funded by the Lamont Climate Center with support from the NASA Interdisciplinary Program and logistical support from NSF.

http://www.ldeo.columbia.edu/~dporter/Kullorsuaq/

Bottom Feeders

Geopoetry - Fri, 08/15/2014 - 10:28
 Yuki Morono

Microscopic images: Yuki Morono

Graduate students, microbe goo …
What is it that links the two?
It seems that both life forms are found
Where electron donors (food) abound!
Sed rates, organic stuff control
Cell distribution on the whole.
New techniques birth a new notion:
Sub-seafloor mass, the same as ocean.

_______________________________

Further reading:

Downsizing the Deep Biosphere, Perspective, Science 2012

Global distribution of microbial abundance and biomass in subseafloor sediment, Kallmeyer et. al., PNAS 2012

Katherine Allen is a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory.

Bird Brain

Geopoetry - Fri, 08/08/2014 - 10:17
Science 2012

Science 2012

A pigeon’s got cells in its brain
That link up with its inner ear.
Despite any wind, fog, or rain,
These talented birds, they can steer!
The magnetic field is their guide
(At bygone reversals: a rumpus?)
A field vector’s measured inside
A bird-brain equipped with a compass!

_____________________________

Further reading:

Neural Correlates of a Magnetic Sense, Wu & Dickman, Science, 2012

Katherine Allen is a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory.

Deep Sea Plough

Geopoetry - Fri, 08/01/2014 - 10:00
 2011room5mgk.wikispaces.com

Photo: 2011room5mgk.wikispaces.com

Giant fleets the oceans trawl,
Gasping fish they skywards haul.
Not just critters do they move,
But sediments they push and groove …
Ten times greater their extent
Than the land that farmers dent!
What will come of shelf slopes now,
Underneath the deep-sea plough?

___________________________

Further reading:

Ploughing the deep sea floor, Puig et al., Nature 2012

Katherine Allen is a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory.

A ‘Bumper-Car’ Ride in the Ice Mélange

Greenland Thaw: Measuring Change - Tue, 07/29/2014 - 10:28
Kullorsuaq's thumb is a beacon when on the water. (Photo M. Turrin)

Kullorsuaq’s ‘thumb’ serves a beacon when you are on the water. (Photo M. Turrin)

By this point many people in the village know about our project and greet us with ‘Aluu’ (Greenlandic Hello) as we move back and forth down the steep hill to the small harbor. We are anxious to get back on the water but we need more benzene and are looking for a swivel that Magnus has suggested will improve the function of the line we are using on the CTD casts.

Magnus and Dave work on improving the CTD connection to the.  (Photo M. Turrin)

Magnus and Dave work on improving the CTD connection to the. (Photo M. Turrin)

Like many places around the world Sundays in Kullorsuaq get off to a slow start. The local branch of the Pilersuisoq, a state owned general store with branches throughout Greenland, doesn’t open until 11AM on Sundays meaning little happens until close to noon. In this village the store serves as a type of community hub, it is where you purchase benzene, boating line, swivels, shackles, cigarettes, food and any other gear one might need for time out on the water.

Gabriel Petersen navigates through the ice with the GPS (Photo M. Turrin)

Gabriel Petersen navigates through the ice with the GPS (Photo M. Turrin)

Gabriel arrives at 11:30 AM as planned and although we can’t find the swivel Magnus had suggested we have a few back up options and so we begin to load. Dave hands Gabriel the GPS he loaded with a map and sample points. We learned yesterday that Gabriel really enjoys using this to navigate, employing his knowledge of the local waterway and the GPS points to smoothly move us as close as possible to the sample points. We head out.

The local community talked of the distinction between large and small icebergs. Minitoq,the large iceberg, were described as being  more tabular in shape, very high and straight sided, extremely large and more dangerous when they split or broke apart because of the large waves they could generate or the sudden ice fall that could bury a boat.  The iceberg pictured here was not a minitoq but was large enough to be skirted with a respectful distance in the boat.

The local community talked of the distinction between large and small icebergs. Minitoq, the large iceberg, were described as being more tabular in shape, very high and straight sided, extremely large and more dangerous when they split or broke apart because of the large waves they can generate or the sudden ice fall that can bury a boat. The iceberg pictured here was not a minitoq but was large enough to be skirted with a respectful distance in the boat.

Today’s plan is to extend the sampling to include a wider region of the water exchange between Alison (Nanatakavsaup), the surrounding ocean and the connection to Hayes glacier. At the Village Meeting we had queried the local fisherman about the iceberg exit pathways for both Alison and Hayes to confirm or correct information we have gleaned from satellite imagery. These pathways should be where the water is the deepest providing the best connection to the open ocean, the measurements we are after. On the water Gabriel and Magnus were able to provide more context to the discussions showing us regions that are shallow with larger icebergs ‘fast’ or grounded to the bottom, and other areas where the depth allows the icebergs to move more readily through to the open ocean.

Dave Porter and Magnus Petersen enjoy a koffemik while Gabriel navigates with the GPS (Photo M. Turrin)

Dave Porter and Magnus Petersen enjoying what we called a ‘boat kaffemik’. Gabriel is intent on the GPS as he navigates to the next sample spot. (Photo M. Turrin)

The Day 2 plan is just as aggressive as Day 1 with a minimum of 8 sample points intended. We expect the workday will last a full 8 hrs. again. Each day when we load into the boat Magnus pulls out a few surprises- a thermos of coffee complete with a box of sugar lumps, and snacks.

Greenlandic cake and coffee become a Kaffemik on the water. (Photo M. Turrin)

Greenlandic cake and coffee become a Kaffemik on the water. (Photo M. Turrin)

Today he has brought Greenlandic Cakes which include several loaves of cake with raisins and a chocolate glazed finger cake. It will be just like a ‘Kaffemik’, the name for a popular open-house Greenlandic gathering of friends and family with coffee, cakes and visiting. We had been included in one a few days earlier in honor of a 15th birthday celebration in one of the local families. On a cool day in the small Poca 500 this is a real celebration with the coffee and food supplies layered on wrappers in the fishing line bucket.

When out on the water icebergs fill your vision in every direction. (Photo M. Turrin)

When out on the water icebergs fill your vision in every direction. (Photo M. Turrin)

The first few sample points go extremely well, we have a protocol down that seems efficient and we are smoothly moving through the sites. A small island appears which is not on our map images or the map we purchased in Upernavik. The shallower depths in this area match with ‘fast’ or grounded icebergs and requires an adjustment in two of the sample points of our transect.

Gabriel and Magnus climb to a high point to get a better view of the  dense ice pack in front of Alison fjord. (Photo M. Turrin)

Gabriel and Magnus climb to a high point to get a better view of the dense ice pack in front of Alison fjord. (Photo M. Turrin)

We complete 8 points with a bit of time left in our 8 hour day to fit in additional sampling. The hope is to still collect a transect of 3 points close in across the mouth of the glacier but we have not navigated into that ice congested area today to see if it is possible. We consult with Magnus and Gabriel – it is 18 km further in from where we are currently which could take an hour or more with the ice. ‘Suu’ (yes) they answer, they are willing to try. (Suu is pronounced with a quick inward most gasp of air and punctuates much of their conversation. Some speakers, like Magnus, follow it with a short inward whistle for emphasis.) As Gabriel moves through the ice it closes around us so he suggests navigating in to land to climb up high for a vantage point. He pulls over immediately and we clamber out to see what we can see. Gabriel can see what might be a pathway close to the north edge of Alison’s fjord outlet.

We found shells of sea urchins, mussels and Greenlandic scallops along the northern flank of Alison fjord. Dropped by the sea birds they seemed out of place against the ice scraped rock. (Photo M. Turrin)

We found shells of sea urchins, mussels and Greenlandic scallops on the southern flank of Alison Fjord. Dropped by the sea birds they seemed out of place against the ice scraped rock. (Photo M. Turrin)

We move towards the possible ice opening in what feels like boat bumper cars. The ice is banging against the sides of the boat with regular thumps and knocks as Gabriel maneuvers expertly through the maze of ice mélange. Periodically I look back and he smiles and laughs when he catches my eye – hard to tell if he is trying to encourage me or if he is enjoying showing how well he can navigate the ice debris. We make it across the front and in a bit along the north edge of the fjord before Gabriel suggests another lookout view is needed, and we stop to clamber up the rocks that form the northern flank of the Alison glacier outlet.

A look out is taken by our guides from on top of Alison Fjord's northern flank. (Photo M. Turrin)

A look out is taken by our guides from on top of Alison Fjord’s northern flank. (Photo M. Turrin)

This time the news is not so good. The ice is pretty densely packed. Magnus explains that Gabriel had been in this area just a few days ago edging his way up bit by bit to try to get to the front edge of the glacier to drop his fishing line. When he tried to work his way back out he had been stuck for several hours in the tightly packed ice and is reluctant to take us into that situation, especially this late in the day and with a threat of rain in the sky.

Reluctantly we take a look at the ice before us. It is densely compacted. Gabriel notes he can maneuver us back to resample one point we collected near the center of the glacier on Day 1. We are happy with this consolation for all the navigating through the ice.

 

 

Alison Fjord filled with icy mélange. (Photo M. Turrin)

Alison Fjord filled with icy mélange. (Photo M. Turrin)

As we collect this last site the rain begins to fall, and turns to a sharp biting storm on the way back to Kullorsuaq. Gabriel notes a seal just meters from the boat as we travel and quickly slows so we can get a look. His sharp eyes have been spotting seals all day but they pop up quickly and we hardly catch a glimpse before they are gone. This time the seal is much closer and we see its full head and flipper emerge. When asked if they could identify the type Magnus noted without hesitation “ours” – claiming it as the Greenlandic seal.

Project Information: Dave Porter and Margie Turrin are in northwest Greenland working with local community members to collect water column temperature profiles. The Leveraging Local Knowledge project will work with members of local Greenlandic communities to collect water measurements in the fjords. This will assist in determining if warming Atlantic Ocean water is circulating up through Baffin Bay where it enters the fjords to lap against the frozen glacier footholds, causing them to loosen their hold on the rock below. Alison Glacier (74.37N and 56.08W) is selected as the project focus. Emptying into Melville Bay to the east of Kullorsuaq Island and has been undergoing dramatic change over the last decade.

The project is funded by the Lamont Climate Center with support from the NASA Interdisciplinary Program and logistical support from NSF.

http://www.ldeo.columbia.edu/~dporter/Kullorsuaq/

 

 

 

 

 

 

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