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What Caused California's Napa Earthquake? - LiveScience

Featured News - Mon, 08/25/2014 - 11:00
Lamont-Doherty seismologist Felix Waldhauser comments on the magnitude 6 earthquake that struck Northern California on Sunday.

Faint Young Sun

Geopoetry - Fri, 08/22/2014 - 09:31
  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

Epic Drought in West is Literally Moving Mountains - Climate Central

Featured News - Fri, 08/22/2014 - 08:47
Lamont-Doherty seismology klaus Jacob comments on a new study showing that California's extended drought has raised the landscape nearly half an inch in the last 18 months.

Reflections of a Changing North

Greenland Thaw: Measuring Change - Fri, 08/22/2014 - 07:48
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/

As Messenger Nears Crash Landing on Mercury, Scientists Race to Collect Data - Baltimore Sun

Featured News - Wed, 08/20/2014 - 11:00
"We've had a lot of bonuses on this mission," said Lamont-Doherty director Sean Solomon, principal investigator of NASA's Messenger mission to Mercury. "We're in new territory for spacecraft."

How Climate Shaped Human Evolution - Scientific American

Featured News - Tue, 08/19/2014 - 09:30
Swings between wet and dry landscapes pushed some of our ancestors toward modern traits—and killed off others, writes Lamont-Doherty scientist Peter deMenocal.

In Many Spots, Hudson Unsafe for Swimming - Legislative Gazette

Featured News - Mon, 08/18/2014 - 11:00
Cites ongoing water sampling in the Hudson River led by Lamont-Doherty and partner institutions.

Bottom Feeders

Geopoetry - Fri, 08/15/2014 - 09:28
 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.

Underwater, Another Carbon Problem - Columbia Magazine

Featured News - Thu, 08/14/2014 - 11:26
A study by Lamont-Doherty geochemist Bärbel Hönisch finds that the oceans’ acidity doubled during the Paleocene Eocene Thermal Maximum in a few thousand years.

Can a Cold War Remnant Help Stem the Slaughter of Elephants? - Columbia Magazine

Featured News - Thu, 08/14/2014 - 11:24
A profile of Lamont-Doherty scientist Kevin Uno and a new dating technique that may help combat poaching of African elephants.

Rockland Scientists Solve Mystery of World Trade Center Ship - (Rockland, N.Y.) Journal News

Featured News - Fri, 08/08/2014 - 11:00
Lamont tree-ring scientists Neil Pederson and Rosanne D'Arrigo discuss their analysis of timbers in the sailing ship found beneath the World Trade Center.

Bird Brain

Geopoetry - Fri, 08/08/2014 - 09:17
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.

Ancient Piles of Clams Reveal Peek into El Niño's Past - Science

Featured News - Thu, 08/07/2014 - 11:00
Lamont-Doherty scientist Mark Cane comments on a new study finding that the El Niño climate pattern has remained largely unchanged for the last 11,000 years.

World Trade Center Ship Gets Its Birth Date - New Yorker.com

Featured News - Thu, 08/07/2014 - 08:58
Profile of Lamont tree-ring scientist Neil Pederson.

Centuries-Old Ship at Ground Zero Likely from Philly - CNN.com

Featured News - Wed, 08/06/2014 - 14:04
Cites research by Lamont-Doherty's tree-ring lab.

What's a ship from Colonial Philadelphia doing under the World Trade Center? - Philadelphia Inquirer

Featured News - Mon, 08/04/2014 - 10:04
Lamont's Tree-Ring Lab traces the age and origins of the sailing ship found at the World Trade Center site four years ago.

Deep Sea Plough

Geopoetry - Fri, 08/01/2014 - 09:00
 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.

Tree Rings Solve World Trade Center Ship Mystery - History Channel

Featured News - Wed, 07/30/2014 - 13:51
Using tree rings, scientists at Lamont-Doherty have identified the origins of a wooden ship unearthed at the former World Trade Center site in Manhattan four years ago.

Mystery of Shipwreck under World Trade Center Solved - Daily Mail

Featured News - Tue, 07/29/2014 - 11:00
Cites tree-ring research by Lamont-Doherty scientists.

A ‘Bumper-Car’ Ride in the Ice Mélange

Greenland Thaw: Measuring Change - Tue, 07/29/2014 - 09:28
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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