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A Meeting for the Kullorsuaq Community

Greenland Thaw: Measuring Change - Sat, 07/19/2014 - 20:58
Our community meeting was held in the new Kullorsuaq school. (Photo D. Porter)

Our community meeting was held in the new Kullorsuaq school, the blue and white building in the center of the cluster of buildings . (Photo D. Porter)

Søren, a local teacher in Kullorsuaq and our contact here, returned from a summer trip home to Denmark on today’s helicopter. He is instrumental in building a link to the community members suggesting we start with a meeting to explain our project to the residents.  We jot down a few lines for a flier that will be translated first into Danish and from there into Greenlandic to be posted around town.  We then head down to the waterfront to look for boating prospects. It seems that many of the local fishermen have gone Narwal hunting further north but there are several good prospects for boats that Søren will scout further as several of the fishermen are sleeping.  The fishing is better right now at night and with 24 hours of daylight day or night fishing doesn’t really seem to matter.

Magnus and Gabriel meet with Dave to discuss the planning for our measurements. (Photo M. Turrin)

Magnus and Gabriel meet with Dave to discuss the planning for our measurements. (Photo M. Turrin)

Within what seems to be hours news has spread around the community that we are looking for a boat and we have been introduced to Gabriel and his cousin Magnus. Gabriel has a sturdy trustworthy boat and Magnus can translate for us.  We have a team. We will have to make some adjustments as Gabriel has a winch, but it is a hand crank.  We have a power winch but he does not have a battery available so we will need to switch the line to make it work.  The loose ice is also shifting Gabriel notes which might help our ability to reach the sites we hope to sample.

Fishermen and community members from the town meeting. (Dave, Edvin (meeting translator), Søren, Gabriel, Ella, Magnus in the back row). (Photo M. Turrin)

Fishermen and community members from the town meeting. (Dave, Edvin (meeting translator), Søren, Gabriel, Ella, Magnus in the back row, other community members front row). (Photo M. Turrin)

The town meeting is an opportunity to share information.  We cover the project goals, existing studies and resulting understanding of ice/ocean interactions around Greenland, show the CTD instrument (for measuring conductivity, temperature and depth) and explain why we are here in Kullorsuaq.  We then gather around the maps we have brought and learn from the local fishermen about water depths, ice conditions, and recent changes in the area around Kullorsuaq.

Gathering feedback from the community members on depths in the fjords. (Photo M. Turrin)

Gathering feedback from the community members on depths in the fjords. (Photo M. Turrin)

According to the fishermen the area in front of Allison is much deeper than the small amount of available data had shown.  The best fishing is right in front of the glacier – what we call Alison they smile and call Nanatakavsaup.  The depth is great there and they let down lines 1000 meters long to hook the Greenlandic Halibut.  They let the line stay an hour or so but not too long so they don’t feed their catch to the Greenlandic shark that share the water. We ask them to jot down on the map wherever they know depths.  Some depths they know from dropping their lines, others they learned from larger fishing boats that came into the area with depth finding sonar.

Amasat a small fish that arrived recently in northwest Greenland. (Photo M. Turrin)

Amasat a small fish that arrived recently in northwest Greenland. (Photo M. Turrin)

New fish have moved in over the last few years. Cod, Catfish and Salmon have moved into the area and Amasat arrived about 7 years ago. Amasat were smaller when they first arrived but they have now put on a little size, although they are still only 6-7 inches in length.  Like sardines they are eaten completely, fins, bones and head.

The night view of the  Kullorsuaq waterfront where the darkness never comes at this time of year. (Photo M. Turrin)

The night view of the Kullorsuaq waterfront where the darkness never comes at this time of year. (Photo M. Turrin)

The meeting runs until everyone has added and shared what they can. The locals note that the ice conditions can turn around in a day so we are hopeful about our ability to get up close to the front of the glacier when we head out in the morning with Gabriel and Magnus.

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/

‘Thumbs Up’ for Travel to Kullorsuaq

Greenland Thaw: Measuring Change - Thu, 07/17/2014 - 17:46
The local coastline has been steeped in fog which prevents helicopters from flying the Upernavik to Kullorsuaq leg. (Photo M. Turrin)

The local coastline has been steeped in fog which prevents helicopters from flying the Upernavik to Kullorsuaq leg. (Photo M. Turrin)

For the last few days we have been laying the groundwork for getting to Kullorsuaq.  We have missed flights due to engine difficulties and have been grounded due to dense fog along the coastline. Today we are assured the helicopter will fly, taking us to our science destination.

While waiting at the airport for our helicopter, a small plane arrives from Upernavik filled with a local sports team decorated with medals hanging from ribbons around their necks. Tossing coins in celebration is part of the reception. (Photo M. Turrin)

While waiting at the airport for our helicopter, a small plane arrives from Upernavik filled with a local sports team decorated with medals hanging from ribbons around their necks. Tossing coins and a Greenlandic cheer set against the fjord is part of the celebration. (Photo M. Turrin)

Our flight is delayed a few hours due to low-lying fog. At the small airport a smiling woman approaches us asking our plans in one word “Kullorsuaq?”  We smile and nod and she grins broadly motioning that she and her daughter are going there too – it is their home she manages to convey.

Landing at the Kullorsuaq ‘helipad’. The helipad is surrounded by canisters of gasoline used to refuel for the return leg. The local transport of luggage and gear is a front loader that delivers the gear to your door. (Photo M. Turrin)

Landing at the Kullorsuaq ‘helipad’. The helipad is surrounded by canisters of gasoline used to refuel for the return leg. The local transport of luggage and gear is a front loader that delivers the gear to your door. (Photo M. Turrin)

Community turns out to wait for helicopter.  Child is holding a Greenlandic flag. (Photo M. Turrin)

Community turns out to wait for helicopter. Child is holding a Greenlandic flag. (Photo M. Turrin)

There are five on our helicopter, our friend from the airport and her young daughter and another woman who slides to the middle seat and willingly becomes our ‘navigator’, pointing on the map and motioning in gestures to us regularly. She mimes birds, seals, steep cliffs, and finally the thumb that marks our final destination – Kullorsuaq, or Big Thumb, named for the prominent thumb shaped rock that projects skyward in the middle of the small island. Some maps use the Danish name Djoevelens Tommelfinger (Devil’s Thumb) a name that Edvard had noted was in reference to the difficult currents that in stormy conditions can surround the island and threaten a boat.

 

 

 

 

 

 

Kullorsuaq Island, Greenland -  the Big Thumb. (Photo M. Turrin)

Kullorsuaq Island, Greenland – the Big Thumb. (Photo M. Turrin)

Now that we have arrived in Kullorsuaq we are in reach of the fjord we have come to measure. Communication is a challenge – a word or two meets with smiles and agreement but ‘hello’ and ‘bye’ seem to be the extent for most.  The village is small, overlooking a southern spur on the main fjord.  Our goal is to travel to the north where Alison glacier empties, so we climb to a high point to see if we can get a better idea of the ice extent.  From our vantage we can see open water, which is encouraging, but we don’t have a view of the full fjord where conditions may differ.

Overlooking the small village of Kullorsuaq. (Photo M. Turrin)

Overlooking the small village of Kullorsuaq. (Photo M. Turrin)

A check in later with the science team in Kangerlussuaq gives us the disappointing news that the satellite image shows that sometime between the 8th and 11th Alison fjord has filled with mélange (chunks of ice). The innermost data points will be unreachable unless conditions change so we will spend a few hours re-planning collection points so we are ready if current conditions persist. Tomorrow the teacher we have been in contact with in the local school is due to return and we can begin to build connections with the local community members, asking for their help in traveling into the fjord.

Looking down on the bay from atop the western end of Kullorsuaq. (Photo M. Turrin)

Looking down on the bay from atop the western end of Kullorsuaq. (Photo M. Turrin)

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/

The Son of a Hunter

Greenland Thaw: Measuring Change - Mon, 07/14/2014 - 22:36
Dave (r) speaks with Edvard (l) about his life as a young Greenlandic growing up as the son of a hunter. (Photo M. Turrin)

Dave (r) speaks with Edvard (l) about his life as a young Greenlandic growing up as the son of a hunter. (Photo M. Turrin)

A visit to the Upernavik museum brought us to ‘Edvard’ a young Greenlandic and the local museum curator.  Embracing the opportunity to practice his English he enthusiastically spent time sharing the historic art and past of the community and his experiences as a young adult growing up in a Greenland that is shifting from one set of cultural norms to another.

Greenlandic mythology (photo M. Turrin)

Greenlandic mythology image (photo M. Turrin)

The first building of the museum is dedicated to traditional Greenlandic art.  An entire room is filled with the creatures of Greenlandic mythology dating back to well before the Danish arrived in the land. The focus of the art revolves around the challenge of the life of a hunter: Ingnerssuit the underground spirits who weep with the springtime cracking of the ice which ends the winter hunt season; Imap Ukua, mother of the sea who must right the evil deeds of all mankind by releasing the seals that have become bound, thus enabling the hunters’ success; Anguit the spirit and looks like a seal who guides the success of the hunt.

The second building is filled with skins, boats and the tools of the hunt.  Seals dominate the display but a walrus and narwal are also on exhibit.  The life of a hunter is hard, it is a test of strength, seal against man.  Edvard explains that one will lose and it is sometimes the hunter.  A choice must be made whether to release the catch or be pulled to their death.  It takes physical strength, understanding of the situation and conditions and the ability to judge when to continue and when to let go of the hunt. A hunter is a respected member of the community, there is much to know in being a good hunter.

Greenlandic (harp) seal skin with the horseshoe shape on its back. (Photo M. Turrin)

Greenlandic (harp) seal skin with the horseshoe shape on its back. (Photo M. Turrin)

Here Edvard begins to talk of his own father, born a hunter. For many years he supported his family hunting seal, polar bear and whale.  Both Menke & Narwal (monodon monoceros – meaning one horn one tooth) were part of his catches over the years. He loved the life of a hunter and Edvard, his son, was anxious to join in his trips, asking as a young son if he too could go.  His father was careful in sharing this hunting life with his son, seeing that change was coming and that the life of a hunter was no longer going to be a way for many of the people.  He did not want Edvard to join him in hunting for fear he would like it too much, for he knew that Edvard was born with a hunter’s spirit just as he was himself.  He wanted his son to be free to have a different life.

Anguit, in Greenlandic mythology the spirit who looks like a seal and guides the success of the hunt. (Photo M. Turrin)

Anguit, in Greenlandic mythology the spirit who looks like a seal and guides the success of the hunt. (Photo M. Turrin)

By 2000 Edward’s father’s love for hunting could not continue to sustain their family.  The ice season had shortened, and the changes in the ice meant that he could hunt for only 5 or 6 months, not enough to support his family.  For musk ox there was a lottery designed to ensure that not too many were taken, while offering a protection for the animal it caused problems for the hunters who depended on their meat and skins. Hunters today must also be fishermen taking advantage of the open water where the ice once filled the bay. That is a hard life.

Ingnerssuit the underground spirits who weep with the springtime cracking of the ice which ends the winter hunt season (Photo M. Turrin)

Ingnerssuit the underground spirits who weep with the springtime cracking of the ice which ends the winter hunt season (Photo M. Turrin)

Edvard’s father now drives a truck in the town hunting only as a hobby, able to join a friend who continues to fish and hunt for a livelihood.  The knowledge of where the prey will be, the water depths and currents, all the pieces that are essential to a successful hunter are still valued, but the changed conditions means there is not the ability to support all who once hunted. The changes in the ice are having a direct impact on the Greenlandic people.  Perhaps we should turn to the Greenlandic mythological spirits and ask for their help.  Where are Anguit and Imap Ukua?  Are the Ingerssuit weeping so loudly the other gods can not hear?

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/

The Changing Upernavik Waterfront

Greenland Thaw: Measuring Change - Mon, 07/14/2014 - 08:01

Leveraging Local Knowledge to Measure Greenland Fjords: Understanding the Community 

GreenlandicLight2Sm

Project location. Currently we are located in Upernavik prior to moving on to Kullorsuaq.

Project location. Currently we are located in Upernavik prior to moving on to Kullorsuaq.

Project Background: Changing conditions in Greenland’s northwest glaciers over the last decade have led to a range of questions about water temperature and circulation patterns in the fjords where ocean water meets the glacial fronts.  We can use satellites to measure the loss of elevation, the acceleration of ice flow, or the retreat of ice from a glacier, but we can’t use satellite measurements to collect water column temperature profiles. Water column profiles would allow us to better determine how much melt is possible at the glacier connection to the ocean, and help us pinpoint why neighboring glaciers are behaving differently.

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.

Our Journey: Our research trip to the small village of Kullorsuaq is a journey that will start 200 kms to the south in the community of Upernavik, located 800 kms north of the Arctic Circle. Flying in on a small 37 seat Dash 7 airplane we overlook a coastline that is lined with glaciers flowing into a bay that is dotted with islands.  Most are uninhabited, but Upernavik is home to a population of 1500 permanent residents. An island community, the main employment is fishing with the waterfront sporting a range of both commercial and smaller independent fishing boats.

Fishing

Fishing is a major occupation in this waterfront community (Photo M. Turrin)

Upernavik town was established by the Danes in the late 1700s but trade and a religious mission in the early 1800s cemented it as a permanent settlement. The southern end of the island is dotted with a cross covered graveyard representing the religion the Danish settlers brought and the practice of the current community. Christmas, Three Kings Day and other religious holidays are all causes for the community to celebrate. This week the priest will visit Upernavik to celebrate three weddings (Friday and Saturday) and the Confirmation (Sunday).  With all such events scheduled for when the priest can preside the parties and celebrations will involve the whole community for days. Celebration and gatherings are a large part of this community’s practice.

Upernavik graveyard (Photo M. Turrin)

Upernavik graveyard (Photo M. Turrin)

The Setting: The icebergs being sloughed from the neighboring glaciers dominate the horizon, littering the waterfront with ice ranging from house-sized blocks to looming masses that appear as large as the neighboring islands. Looking around at the open water it is hard to imagine the origin of these large masses of ice.  The closest blocks of ice move during the course of the day, shifting back and forth from north to south and back again.  With the shifting and changing of the icebergs the sound of the settling and collapsing of ice is drilled into our consciousness – the sharp crack of the ice as if fractures and the larger canon-like rumble as sections break and fall into the water.

Large Iceberg on the waterfront (Photo M. Turrin)

Large Iceberg on the waterfront (Photo M. Turrin)

Our local host, a Dane who has lived in Upernavik for 40 years, has fully blended himself into the community where he and his family are well known and liked by both the Inuit and the Danish population. When he learns of our project he observes that in his time here ice cover has significantly changed. He recalls his early years here when the ice in May was so solid in the bay that visiting boats had to drop dynamite on the ice to open a pathway. He points to the open water and the line of haze that hangs on the horizon offering a cause, ‘global heating’.

The Community of Upernavik (Photo M. Turrin)

The Community of Upernavik (Photo M. Turrin)

Other changes have hit Upernavik.  We meet a Danish couple who had spent 4 years living in the community, now returning after 30 years to ‘close out their memories’.  They spoke with fondness of this lost time when they raised their small children as they worked as a teacher and a nurse.  With a team of 10 dogs ‘Lars’ had hunted Greenlandic seal and still had a sharp eye picking a bobbing seal head out on the horizon. They spoke of the people numbering 900 while the Greenlandic dogs had numbered 3000, many times more than the dogs are now. Dogsleds were an important part of that older Upernavik when individual hunting and fishing were the mainstay of the community. While hunting and fishing are still important today Lars notes that things have changed becoming less rugged for an individual. Whether the changes in ice cover have played a part in this is hard to determine.

Bear Skin

Polar Bearskin hangs off front porch in Upernavik (Photo M. Turrin)

In our few days here in Upernavik we learn that residents are happy to help, they have networks that reach from one island community to another.  Names and contacts are offered freely – “try this person for a place to stay”, “this teacher may be interested in helping you”.  It is this networking of local people that we will rely on for the project. Their overall interest in what is happening to their community will be an important part of its long term success.

Glaciers in Upernavik Waterfront (Photo M. Turrin)

Icebergs in Upernavik Waterfront (Photo M. Turrin)

 

Leveraging Local Knowledge to Measure Greenland Fjords:
Dave Porter and Margie Turrin are in northwest Greenland working with local community members to collect water column temperature profiles.  The project is funded by a Lamont Climate Center grant with support from the NASA Interdisciplinary Program and logistical support from NSF.

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

 

 

The Changing Upernavik Waterfront

Arctic Thaw: Measuring Change - Mon, 07/14/2014 - 08:01

Leveraging Local Knowledge to Measure Greenland Fjords: Understanding the Community

GreenlandicLight2Sm

Project location. Currently we are located in Upernavik prior to moving on to Kullorsuaq.

Project location. Currently we are located in Upernavik prior to moving on to Kullorsuaq.

Project Background: Changing conditions in Greenland’s northwest glaciers over the last decade have led to a range of questions about water temperature and circulation patterns in the fjords where ocean water meets the glacial fronts. We can use satellites to measure the loss of elevation, the acceleration of ice flow, or the retreat of ice from a glacier, but we can’t use satellite measurements to collect water column temperature profiles. Water column profiles would allow us to better determine how much melt is possible at the glacier connection to the ocean, and help us pinpoint why neighboring glaciers are behaving differently.

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.

Our Journey: Our research trip to the small village of Kullorsuaq is a journey that will start 200 kms to the south in the community of Upernavik, located 800 kms north of the Arctic Circle. Flying in on a small 37 seat Dash 7 airplane we overlook a coastline that is lined with glaciers flowing into a bay that is dotted with islands. Most are uninhabited, but Upernavik is home to a population of 1500 permanent residents. An island community, the main employment is fishing with the waterfront sporting a range of both commercial and smaller independent fishing boats.

Fishing

Fishing is a major occupation in this waterfront community (Photo M. Turrin)

Upernavik town was established by the Danes in the late 1700s but trade and a religious mission in the early 1800s cemented it as a permanent settlement. The southern end of the island is dotted with a cross covered graveyard representing the religion the Danish settlers brought and the practice of the current community. Christmas, Three Kings Day and other religious holidays are all causes for the community to celebrate. This week the priest will visit Upernavik to celebrate three weddings (Friday and Saturday) and the Confirmation (Sunday). With all such events scheduled for when the priest can preside the parties and celebrations will involve the whole community for days. Celebration and gatherings are a large part of this community’s practice.

Upernavik graveyard (Photo M. Turrin)

Upernavik graveyard (Photo M. Turrin)

The Setting: The icebergs being sloughed from the neighboring glaciers dominate the horizon, littering the waterfront with ice ranging from house-sized blocks to looming masses that appear as large as the neighboring islands. Looking around at the open water it is hard to imagine the origin of these large masses of ice. The closest blocks of ice move during the course of the day, shifting back and forth from north to south and back again. With the shifting and changing of the icebergs the sound of the settling and collapsing of ice is drilled into our consciousness – the sharp crack of the ice as if fractures and the larger canon-like rumble as sections break and fall into the water.

Large Iceberg on the waterfront (Photo M. Turrin)

Large Iceberg on the waterfront (Photo M. Turrin)

Our local host, a Dane who has lived in Upernavik for 40 years, has fully blended himself into the community where he and his family are well known and liked by both the Inuit and the Danish population. When he learns of our project he observes that in his time here ice cover has significantly changed. He recalls his early years here when the ice in May was so solid in the bay that visiting boats had to drop dynamite on the ice to open a pathway. He points to the open water and the line of haze that hangs on the horizon offering a cause, ‘global heating’.

The Community of Upernavik (Photo M. Turrin)

The Community of Upernavik (Photo M. Turrin)

Other changes have hit Upernavik. We meet a Danish couple who had spent 4 years living in the community, now returning after 30 years to ‘close out their memories’. They spoke with fondness of this lost time when they raised their small children as they worked as a teacher and a nurse. With a team of 10 dogs ‘Lars’ had hunted Greenlandic seal and still had a sharp eye picking a bobbing seal head out on the horizon. They spoke of the people numbering 900 while the Greenlandic dogs had numbered 3000, many times more than the dogs are now. Dogsleds were an important part of that older Upernavik when individual hunting and fishing were the mainstay of the community. While hunting and fishing are still important today Lars notes that things have changed becoming less rugged for an individual. Whether the changes in ice cover have played a part in this is hard to determine.

Bear Skin

Polar Bearskin hangs off front porch in Upernavik (Photo M. Turrin)

In our few days here in Upernavik we learn that residents are happy to help, they have networks that reach from one island community to another. Names and contacts are offered freely – “try this person for a place to stay”, “this teacher may be interested in helping you”. It is this networking of local people that we will rely on for the project. Their overall interest in what is happening to their community will be an important part of its long term success.

Glaciers in Upernavik Waterfront (Photo M. Turrin)

Icebergs in Upernavik Waterfront (Photo M. Turrin)

 

Leveraging Local Knowledge to Measure Greenland Fjords:
Dave Porter and Margie Turrin are in northwest Greenland working with local community members to collect water column temperature profiles. The project is funded by a Lamont Climate Center grant with support from the NASA Interdisciplinary Program and logistical support from NSF.

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

 

 

Glacier Marks on Mount Chirripó

Sculpting Tropical Peaks - Wed, 07/09/2014 - 16:39

By Max Cunningham
June 12, 2014
We continued to sample boulders in Valle de Las Morrenas, Valle Talari, where the hostel sits, and several places along Mount Chirripó’s ridgeline.

Max 7.1

Large boulders of granodiorite line the ridge of Mount Chirripó. These are likely produced by exfoliation, a process that occurs in response to stress release associated with the melting of glacier ice.

The view from the top of Mount Chirripó is spectacular.  Looking out along the ridge I could see huge boulders of granodiorite produced by exfoliation, or the response of rock at the surface to the removal of ice.

Max 7.2

Striations in the meta-sandstone at the summit of Mount Chirripó point down the axis of Valle de Los Lagos, (a mechanical pencil and sample bag are included in the picture for scale, the pencil points in the direction of striations). Striae are a telltale sign of glacial coverage.

The actual summit of Chirripó, however, is a very different kind of rock.  I believe the peak is composed of a sedimentary rock that was melted and then fused back together as the magma that formed the granodiorite rocks moved toward the surface.  This metamorphosed sandstone (meta-sandstone) is extremely hard, and resistant to weathering processes.

In the meta-sandstone near the summit of Mount Chirripó, I discovered glacial striations.  These striations occur at 12,513 feet (the summit is 12,529 feet), which is a good 1,000 feet above the moraines in the upper portion of Valle de Las Morrenas.

Back to Mount Chirripó

Sculpting Tropical Peaks - Tue, 07/08/2014 - 12:14

By Max Cunningham
June 11, 2014

 Volunteers  at the Cloudbridge Reserve stay in a series of houses built in the Costa Rican rainforest.   They work towards returning mountainsides near Mount Chirripó to natural conditions.

Volunteers at the Cloudbridge Reserve are returning the hills near Mount Chirripó to natural conditions.

Mike and I hiked down 7,000 feet from Mount Chirripó to the Cloudbridge
Reserve early on the morning of June 10th to refuel and replenish supplies.

At this point, the Cloudbridge Reserve deserves a special mention.  Tucked away in the forest above San Gerardo de Rivas, volunteers at the Cloudbridge Reserve work to transform old farmland into natural forest.  After the cold ruggedness of the Mount Chirripó summit, the volunteers at Cloudbridge provided an exceptionally welcoming and engaging environment.  Mike and I were extremely lucky to have such a supportive base camp.

I kept an eye out for interesting geomorphology as I walked along the trails of the Cloudbridge Reserve.  The rivers here are particularly beautiful.  The water is clear and blue, and channel beds are floored by bedrock and boulders (all granodioritic in composition, like many of the rocks atop Mount Chirripó).  I was struck by the power of the local rivers; the erosional features carved into this hard, granodioritic rock were impressive.

The raging Chirripó River cuts through granodiorite, about 1 mile away from the Cloudbridge Reserve.

The raging Chirripó River cuts through granodiorite, about 1 mile away from the Cloudbridge Reserve.

After two days of rest and catching up on all we’d missed while isolated on Costa Rica’s highest peak, Mike and I headed back up to Mount Chirripó to continue sampling and to learn more about the processes shaping this landscape.

During our second journey, we hoped to extend our sampling range by venturing farther into glacial valleys and higher onto peaks.  We targeted Valle de Las Morrenas, a valley that we knew well from our first sampling trip and that other researchers had discussed extensively.

Earlier, we sampled boulders from moraines adjacent to large lakes.  This time, we targeted a steep drop-off (what we called a “lip) that occurs in the valley directly below the lakes.  Looking at maps and satellite images, it appeared that the lower valley was actually a remnant cirque:

A 60-foot drop-off separates the upper and lower valleys in this picture.  The lip may represent the retreat of a large glacier that once filled lower Valle de Las Morrenas.

A 60-foot drop-off separates the upper and lower valleys in this picture. The lip may represent the retreat of a large glacier that once filled lower Valle de Las Morrenas.

Our discovery of a large lateral moraine in the lower valley corroborated our hypothesis that a glacier produced the pronounced lip in Valle de Las Morrenas.  The vegetative cover increased substantially as we moved lower in the valley, which made accessing the moraine a real challenge.  After pushing through thick, woody bushes, we finally found ourselves on the crest of the moraine.

From the image it’s hard to tell, but this is actually a pretty big moraine, Max 6.4about 50-60 feet in height.  Meandering rivers cut through cobbles along the moraine’s edge, analogous to what we saw in Sabana de los Leones, only here with water raging through the channel.

Max 6.5We quickly came to realize that the boulder selection on the crest of this lower moraine was a far cry from the beautiful, large, flat boulders we saw along moraines in the upper valley.  Here, boulders seemed to be more deeply weathered, and more sparsely scattered.

While the lack of good boulders for sampling induced a bit of hand wringing (made worse by storm clouds quickly moving up the valley), the effectiveness of weathering on these boulders may add to the story of glaciation at Mount Chirripó.  Deep weathering of boulders suggests that they have been sitting around, exposed to the atmosphere, for a long time.  How long?  Glaciologists have employed relative weathering techniques for centuries to estimate exposure age, but 10-Be dating will tell us for sure.

 

 

Herbie’s Great Adventure: NUM Dendroecological Fieldweek

Kristen de Graauw and Cari Leland

Cari and Kristen here, checking in from Mongolia. This year we were invited to be instructors for the Third National Dendroecological Fieldweek, May 23-29 in Udleg, Mongolia. We arrived to Ulaanbaatar on May 20th so we were fortunate enough to have a few days to recover from some pretty terrible jetlag before beginning the fieldweek marathon. Anyone who has ever attended a fieldweek anywhere in the world knows how challenging (and rewarding!) these events can be. Our first few days of the fieldweek were spent at the NUM (National University of Mongolia) research station near Udleg, a few hours north of UB. We were so happy to see the beautiful countryside for a few days. We got to ride there in this awesome Russian vehicle, which Cari nicknamed Herbie.

 

The roads were rough but Herbie was a trooper and we arrived at the research station safely.

The roads were rough but Herbie was a trooper and we arrived at the research station safely.

We took a break at Teacher’s Pass for a nice panoramic view of the mountains before continuing on to the research station.

We took a break at Teacher’s Pass for a nice panoramic view of the mountains before continuing on to the research station.

The research station was a complex of buildings for housing, a kitchen, and lecture rooms. We shared a cozy room for two and enjoyed beautiful views of the valley and mountains surrounding us.

The NUM Forestry research station

The NUM Forestry research station

Our room from the outside...

Our room from the outside…

..and the inside.

…and the inside (Hi Cari!).

After everyone settled in, we met for the opening ceremony. Baatar gave a nice introduction of the project and the history of the CEME collaboration. There were 8 students in total, and 7 of them were female (girl power!). There was a good mix of participants; from first year undergraduates to PhD students.

Baatar giving the opening ceremony speech.

Baatar giving the opening ceremony speech.

After the opening ceremony we went out to the field. Baatar gave us a guided tour of all the current research projects at the station (there were many!) and the potential sites for the fieldweek. Then we gave a quick lecture on the basics of dendrochronology and headed back towards the research station to discuss potential fieldweek projects.

The flux tower on the research station property. It was pretty impressive.

The flux tower on the research station property. It was pretty impressive.

We noticed Gypsy moth larvae emerging from their cocoons on the ground near the forest.

We noticed Gypsy moth larvae emerging from their cocoons on the ground near the forest.

More gypsy moth larvae after emerging from their cocoons.

More gypsy moth larvae after emerging from their cocoons.

We headed back after a nice hike through the forest.

We headed back after a nice hike through the forest.

Day 2 at the research station was field sampling day. Unfortunately we woke up to a cold and rainy day but that didn’t stop our groups from heading out into the forest. After a long discussion we decided Cari would teach the Climate group and Kristen would teach the Ecology group. Cari’s group headed up the mountain in search of old larch and pine trees to core while Kristen’s group went to a portion of the forest that had been logged. The goal for the climate group was to find moisture-stressed trees and look at the relationship between tree rings and climate. The ecology group’s goal was to determine logging dates and the effects on surviving trees.

Cari’s group preparing to core a large pine near the mountain ridge.

Cari’s group preparing to core a large pine near the mountain ridge.

Kristen’s group coring a living larch near the stump graveyard.

Sundermaa coring a living larch near the stump graveyard for Kristen’s ecology group.

After one of the coldest and rainiest field days we’ve ever experienced we headed back to the field station to thaw and dry ourselves and the cores.

Cari’s group heading back from the ridge.

Cari’s group heading back from the ridge.

While we waited for the cores to dry, the students practiced skeleton plotting.

The students mounting wet cores with tape to help them dry straight.

Margad, Togii, and Badra mounting wet cores with tape to help them dry straight.

Byamba teaching Oyunna a skeleton plotting exercise.

Byambaa teaching Oyunna a skeleton plotting exercise.

The students are working hard on their skeleton plot exercises, while Kristen and Cari check their work.

The students are working hard on their skeleton plot exercises!

Everyone was very anxious to see if their skeleton plots matched!

Everyone was very anxious to see if their skeleton plots matched!

After a rainy day, we were treated with a beautiful sunset.

After a rainy day, we were treated with a beautiful sunset.

The next day we mounted the cores with glue and taught the students how to sand. They quickly learned that a well sanded core took time, patience, and persistence. At the end of the day we headed back to UB to begin laboratory methods.

Sainaa sanding her first core.

Sainaa sanding her first core.

Kristen telling the students they need to sand more! “Sand more!!”

Kristen telling the students they need to sand more…“Sand more!!”

The view from our sanding “room”. Not bad!

The view from our sanding “room”. Not bad!

Back at the university we had to hit the ground running with lab methods. The students skeleton plotted the samples from the research station one day, learned how to do the list method and measure the next day, and finally on the last day they learned how to run COFECHA and read the output files. It was challenging but everyone worked their hardest. The final day was very busy. The students were working on their presentations until the very last minute. The groups did an outstanding job presenting their projects, which made us feel so grateful for being able to teach such a bright and dedicated group of students. During the closing ceremony Baatar gave us both a really nice Mongolian tree and shrub guide book and then presented each student with a certificate of achievement. The students then gave us the most thoughtful gifts of Mongolian art and script.

Oyunna discussing the correlations between climate and pine during the climate group presentation.

Oyunna discussing the correlations between climate and pine tree growth during the climate group presentation.

Baatar presenting Margad with her certificate of achievement.

Baatar presenting Margad with her certificate of achievement.

 Cari, Margad, Togii, Sundermaa, Oyunna, Sainaa, Gerelee, Baatar, Sanaa, Kristen, M?, Byambaa, and Badra.
The whole group after an amazing fieldweek! From the left: Cari Leland*, Margad Ovgonkhuu, Togtokhbayar Erdene-Ochir, Sundermaa Sergelen, Oyunmunkh Byambaa, Sainbayar Gombo, Oyungerel Sereenen, Baatarbileg Nachin*, Oyunsanaa Byambasuren*, Kristen de Graauw*, Myagmarsuren Batdorj, Byambagerel Suran*, and Badar-Uugan Khasbaatar. ( *Instructors)

 

 


Categories: TRL

A Quick Retreat from ‘Mountain Lion’ Savannah

Sculpting Tropical Peaks - Tue, 06/17/2014 - 12:03
Max 5.1

The discovery of a flat grassland leads to a morning of exploration.

By Max Cunningham
June 10, 2014

Mike, Colin and I made meticulous plans for exploring Mount Chirripó before we left New York, but on the way to the summit Mike and I saw something that made us change direction: at about 9,500 feet, a mysterious grassland beckoned beneath jagged peaks. With just one day to go before our trip back to the Cloudbridge Reserve to refuel, we decided to make an early morning trek to this unusual valley to investigate why it is so flat and devoid of vegetation.

Max 5.2

The dry stream bed is sharply cut but lined with angular rocks suggesting minimal erosion.

Over the course of a beautiful, sunny day Mike and I trekked over the rugged terrain from Crestones Base Camp before reaching a sudden transition from forest to grassland. A few things struck us. First, a thin river snakes through this entire shallow valley. Around bends in the river we noticed sharply cut banks where the stream has become more powerful and eroded away the banks.

Max 5.3

A stone marks the place where a lion killed someone in 1956.

Second, we were surprised to find the stream bed completely dry. From a distance, we had expected to find a powerful body of water. In another test of our geomorphology knowledge we discovered that this dry stream bed is paved mostly in cobble-sized rocks, the type you might find on a cobblestone street except these cobbles are sharp and angular instead of smooth and rounded. Mike and I spent the morning walking the Sabena de Leones valley and the more we looked, the more baffled we remained by the processes that shaped this landscape. Why is the river bed dry and its sediment load so large and angular? We hope to find more clues in the coming week.

In the early afternoon, Mike and I stumbled on a small marker along the river channel in Spanish dated 1956. Combining our Spanish skills, Mike and I deduced that the sign commemorated the unfortunate death of a man by mountain lion, and then I realized that Sabana de los Leones  translates to “Savannah of the Lions.” That’s all we needed to know before skedaddling back to the Talari Valley and the security of the Crestones Base Camp.

Landslide Up Close

Sculpting Tropical Peaks - Mon, 06/16/2014 - 12:31

By Max Cunningham
June 9, 2014

Max 4.1

The landslide below the dark rocks in the center of this photo was discovered first in satellite images.

During the last decade, scientists have noticed an apparent rise in catastrophic events in mountain valleys as glaciers retreat and permafrost thaws. Some evidence suggests that thawing glacial valleys are responsible for enormous, fast-moving landslides that can destabilize river dams and cause other damage. Last July, my colleague Colin Stark and others at Lamont identified one such landslide in Alaska.

The idea that catastrophic processes may become more frequent as glacial valleys warm globally is a frightening one, but further information is needed to assess the threat. I came to Mount Chirripó hoping to find evidence of past landslides. Before flying here, Stark and I used high-resolution satellite images to identify potential landslide features on Mount Chirripó. On our second day in the field, Kaplan and I tried to locate them on foot.

We found our first landslide in Valle de los Conejos, a cirque valley carved into Mount Chirripó’s southern side. Apparently, we walked right by it on our previous day of fieldwork; the trees and bushes growing amid the fallen boulders provide an excellent disguise.The glacial debris blends in almost perfectly with the hillside. To highlight it, I have outlined the scarp in red where the failure occurred, but even this image, taken more than a half-mile away, is deceiving. Mike and I spent what felt like hours whacking through thick bushes to get there. You can just make out some of the large boulders in the background.

Max 4.2

Kaplan bushwhacks to the landslide.

From a distance I thought we could scale the landslide, but the house-sized blocks were too big to scramble over.  During the slide, boulders stacked up on each other and formed crevasses and caves that are now covered in treacherous mats of vegetation. I suspect that pumas may sleep in the caves by day if they are able to withstand the altitude.

Mike and I traipsed around the landslide, stopping at various scarps to enjoy the views. The run-out distance appears to be only about a tenth of a mile, and the boulders are densely packed. Looking down, I got the impression that the landslide created a crevasse somewhere between 60 to 100 feet in depth. When did this major failure happen in relation to deglaciation?

Max 4.4

Quartz sampled from the landslide debris may help us discover when the event happened.

Mike and I decided to use our CRN dating tools to find out. We made our way to several boulders on the east side of the landslide, where the rock is sedimentary, unlike the granodiorite found in the Valle de las Morrenas.  Once again, Mike and I found bits of fine-grained quartz in the rocks, indicating we can measure their Beryllium-10 levels to understand how long this landslide has been exposed to cosmic rays. Mike and I think that the extent of weathering on these boulders is a clue to the age of the landslide: For the surface of these boulders to undergo alteration, they probably sat in the same place for a long period of time. Perhaps this landslide is indeed paraglacial, a result of glacier retreat and permafrost thaw. We hope our efforts to measure CRN production here will inform us.

Chiseling Away

Sculpting Tropical Peaks - Fri, 06/13/2014 - 10:52

By Max Cunningham
June 8

Max 3-4

Cunningham chisels away at this glacial moraine for a sample that will reveal when the ice last withdrew.

Our expedition has two main goals: assess glacial erosion features on Mount Chirripó and search for clues of the summit’s age. Were the broad, flat landscapes on Mount Chirripó formed by glacial erosion or a change in tectonic forces pushing the Talamanca Range up about 2.5 million years ago?

A chemical dating technique called Cosmogenic Radionuclide (CRN) Dating may lead us to the answer. This technique will help tell us how long ago the valleys flanking Mount Chirripó eroded, and therefore, whether Mount Chirripó’s high elevation landscape is older than 2.5 million years or whether it eroded into its current shape as recently as 10,000 years ago.

Earth is being constantly bombarded by high-energy protons and neutrons from beyond our solar system, and CRN dating exploits this process. The collision of high-energy particles and atoms in the atmosphere and on rock at Earth’s surface produces new atoms of different mass, or isotopes. Fortunately for many Earth scientists, the impact of cosmic rays and oxygen produces an extremely rare isotope of the element Beryllium: Beryllium-10.  Oxygen is abundant in Earth’s crust, and quartz (SiO2) is among the most common minerals found there. When cosmogenic rays react with quartz at the surface, about six atoms of Beryllium-10 are produced per gram of quartz per year.

Measuring concentrations of Berylium-10 at the surface can potentially tell us how long the rock has been exposed to the atmosphere, and quartz is a particularly convenient mineral for measuring Beryllium-10 concentrations. Mike and I sought out glacial features with quartz-bearing rocks at Mount Chirripó with the hope of understanding whether rocks here were exposed to the atmosphere after the recent retreat of ice.

Max  3-1

Glacial debris can create natural dams where lakes form.

Glacial features jumped out at us during our initial tour of Mount Chirripó. We saw broad cirque valleys, floored by large lakes likely filled during glacial retreat. We also saw striated rocks and moraine ridges scattered with cobbles and boulders. In one valley, Valle de Las Morrenas, we noticed several lakes above the boulder-strewn ridges. This fits in neatly with previous observations of lakes dammed by moraines.

Max 3-2

Kaplan inspects a moraine.

Because moraines are abandoned when the ice retreats, measuring concentrations of Beryllium-10 in boulders on top of moraines may give us an idea of how long ago glacial erosion happened here. After locating boulders sitting on moraines, our next step was to see what the boulders are made of.

 

Max 3-3

Chiseling exposes a fresh surface of quartz.

We discovered that many are granodioritic, an intrusive igneous rock composed of the minerals plagioclase, amphibole and our good friend quartz! Next we took samples to analyze their Beryllium-10 levels in the lab later. Collecting samples is a physically rigorous process, especially in the low-oxygen, rainy conditions at 10,000 feet on Mount Chirripó. With a hammer and a chisel, and a bandanna to protect our faces from shattering rock fragments, we chipped away at the surface of the boulder, hoping to come away with about two pounds of rock to analyze.

We collected samples from boulders on two moraine crests. After months of processing, we hope to be able to describe how long ago glacial ice retreated from different parts of the valley. Calling the day a success, we hiked back through the afternoon rain to Crestones Base Camp.

 

Climbing Mount Chirripó

Sculpting Tropical Peaks - Thu, 06/12/2014 - 15:09

By Max Cunningham
June 7

After arriving in the town of San Gerrardo de Rivas, Mike Kaplan and I immediately started gearing up for our trek to Mount Chirripó.

Our arrival here was somewhat hectic. After landing in San Jose around 10:30 a.m., we hopped a bus to San Isidro de el General, a town just west of Chirripó National Park.  Winding through the rugged mountains of the Talamanca Range, we were treated to spectacular views of central Costa Rica’s countryside. Max 2a

Once in San Isidro de el General, we navigated our way to the local office of Ministerio de Ambiente y Energia de Costa Rica, the government agency that provides research permits for Chirripó National Park. Our contact, Marisol Rodríguez Pacheco, showed remarkable patience with our broken Spanish and helped us pull together some final requirements for the permit.

By 5 p.m., the two of us made base camp at the Cloudbridge Reserve, above the San Gerrardo de Rivas. Founded in 2002, the Cloudbridge Reserve supports researchers in Costa Rica and works towards sustainable forest management. Volunteers at the Cloudbridge Reserve provided us with a beautiful working space and a warm place to sleep.

Max 2-1

The clouds rolled in early, by 9 a.m., on their way from San Isidro de el General in the distance.

The weather here can be erratic.  During the early morning hours the sun is intense and the sky is blue; by 1 p.m. clouds roll in. You can anticipate heavy rain from 4 to 6 every day, and nights are cold.

After taking a day to gather food supplies and find porters to help us carry heavy packs up to Mount Chirripó, Mike and I set off around 4:30 a.m. to make our way to the top of Mount Chirripó before the afternoon rain.

Travelers and locals alike warned us that the hike would be strenuous, and indeed they were correct. The trail leading to Mount Chirripó is steep and rugged (although pristinely maintained), and we gained nearly 5,000 feet in elevation over nine miles of trail.

The trail leading up to Mount Chirripó around 8,000 feet is densely vegetated and humid.

The trail leading up to Mount Chirripó around 8,000 feet is densely vegetated and humid.

One especially difficult aspect of our climb was the dramatic change in climate with elevation. Below 10,000 feet, we trekked through a humid, dense rain forest, but once above about 9,500 feet, the vegetation became sparse and the temperature dropped. At the summit of Chirripó, we rarely experienced temperatures warmer than 60°F.

In terms of Earth surface processes, this dramatic change in environment invokes thoughts about difference in landscape evolution: How does change in altitude, and associated changes in climate, affect erosion processes in the long term? This is just one question we hope our research can eventually inform.

Above 10,000 feet, the climate is extremely different, and so is the terrain.  At high elevations we see broad U-shaped valleys, and cold conditions inhibit dense vegetation growth.

Above 10,000 feet, the climate is extremely different, and so is the terrain. At high elevations we see broad U-shaped valleys, and cold conditions inhibit dense vegetation growth.

After an 8.5 hour hike, we finally reached Talari Valley, a lowland about 500 feet below Mount Chirripó. We made camp at the Crestones Base Camp, a meticulously maintained hostel in the Talari Valley, near Cerro Chirripó. The Crestones Base Camp is home to many travelers seeking the thrill of climbing Mount Chirripó. Impressively, many of the hikers we encountered wake up around 2:30 a.m. to hike the remaining 5,000 feet to the peak of Cerro Chirripo to watch the sunrise over this beautiful mountain. Mike and I made no such plans, and instead rested for a busy week of fieldwork.

Max 2-5

From Crestones Base Camp, you can pick out our hostel with the green roof in this expansive view of Talari Valley.

 

Mount Chirripó: Shaped by Glaciers or Tectonic Forces?

Sculpting Tropical Peaks - Fri, 06/06/2014 - 14:38

By Max Cunningham

Max Cunningham

Max Cunningham

I’m a graduate student at the Lamont-Doherty Earth Observatory and work in Colin Stark’s Earth Surface Processes Group. My research focuses on the role that climate plays in molding Earth’s surface, and how we can use clues carved into landscapes to learn more about climate and climate change in the past.

Since arriving at Lamont-Doherty, I’ve focused my attention on glacial valleys responding to climate change. I want to learn more about erosion in landscapes undergoing a transition from cold, frozen conditions to warm conditions. Questions about the timing of glacial retreat in the past and the erosional processes that occur as landscapes unfreeze are particularly relevant today, as glaciers around the world shrink in response to a warming global climate. max 1

Specifically, I want to learn about the history of glacial erosion in tropical mountains. Features on many tropical peaks around the world suggest that glaciers once persisted at low latitudes, but nearly all of these places are far too warm to sustain glaciers today.

Google Earth images of glacial thumbprints at Mount Chirripo, Costa Rica (left) and Mount Wilhelm, Papua New Guinea (right).  Both mountains are located within 10° latitude of the equator.

Google Earth images of glacial thumbprints at Mount Chirripo, Costa Rica (left) and Mount Wilhelm, Papua New Guinea (right). Both mountains are located within 10° latitude of the equator.

Glaciers are a crucial link between climate and erosion: They form only under very specific climatic conditions and leave very distinctive marks after they retreat. During a glacier’s lifetime, snow accumulates at high elevation and compacts into hard ice that flows downslope; at lower elevations warmer temperatures melt away layers of snow, allowing ice deeper within the glacier to move toward the surface. The total effect of compacting ice above and disappearing ice below is a “scooping” motion, and rocks caught in this “ice scoop” wear away bedrock. A combination of this rock-on-rock wear and other processes produces features unique to glacial erosion, such as circular valleys called cirques. In map view glacially sculpted valleys look like thumbprints in clay.

A somewhat startling realization is that these glacial thumbprints can be found on mountains in hot, tropical places like Costa Rica, Uganda, Kenya and Papua New Guinea. Some major questions arise: How long ago did glaciers carve out valleys in the tropics? How far down mountainsides did glaciers persist in these perennially warm regions? To start honing in on these questions, I’ll be traveling to Costa Rica’s tallest peak, Mount Chirripó, in Chirripó National Park for the month of June.

On Mount Chirripó, which rises to 12,530 feet, glacial thumbprints are clustered a few hundred feet below the summit. River profiles have a distinctive shape, exiting U-shaped valleys along gentle gradients and then breaking suddenly into a steep slope at about 6,500 feet. Waterfalls, or more technically “knickpoints,” form at this steep slope change.

Scientists have studied the unusual glacial thumbprints and clustering of knickpoints at Mount Chirripó. In 2000, researchers at the University of Tennessee identified a series of lakes that formed as a result of glacial erosion. They extracted sediment cores from the lakes and noticed a sharp transition from granular, glacially-produced sediment to organic material with depth in the core. Using 14C radiometric dating, they found that the transition occurred between 12,000 and 9,800 years ago.

Why is that important? Between 20,000 and 10,000 years ago the world was thawing out of an ice age. The 14C dates imply that glaciers persisted at about 12,000 feet at Mount Chirripó as recently as 9,800 years ago. By comparison, North America’s Laurentide ice sheet, which once extended south of New York City, retreated into Canada well before 9,800 years ago.

A 2012 study looked at Mount Chirripó from a different lens. The collision of tectonic plates in the tropical Pacific Ocean pushed Mount Chirripó to its modern elevation, but the timing of this uplift remains unclear. The 2012 study suggested that the clustering of knickpoints could reveal when tectonic uplift began.

Rapid tectonic uplift provides rivers with potential energy that expresses itself in steep slopes that slowly creep up mountainsides, creating a “wave” of erosion that travels up hillslopes. By assuming a “vertical” erosion rate, these researchers estimate that knickpoints at 6,500 feet signify tectonic upheaval that began about 2 million years ago.

The conclusions reached by these independent studies present a major conflict. On the one hand, valleys atop Mount Chirripó may have been carved by glaciers. If this is the case, the landscape must be “young,” as glacial erosion would have occurred during the last 2.5 million years. On the other hand, the valleys at high elevations at Mount Chirripó may represent a landscape that existed before 2 million years ago and rode a pulse of uplift to 12,500 feet.

In other words, two competing hypotheses have emerged: Is Mount Chirripó a sculpture of glacial erosion, or an ancient landscape perched at high elevations by tectonic forces?

My colleague Mike Kaplan and I plan to analyze evidence of past glaciation on Mount Chirripó in an attempt to test these two competing hypotheses. Using a geochemical technique called surface exposure age dating, which will allow us to measure how long rocks at the summit of Mount Chirripó have been exposed to the atmosphere, we will attempt to test how “old” the landscape is—is it relatively young, around 9,800 years old? Or does it predate a massive shift in tectonic uplift that began 2 million years ago?

Clock Is Ticking in West Antarctic

Melting Glaciers-Tracking Their Path - Fri, 05/23/2014 - 12:54
Pine Island Glacier, Antarctica

The leading edge of the floating ice tongue of the Pine Island Glacier, Antarctica. Photo: M. Wolovick

Reports that a portion of the West Antarctic Ice Sheet has begun to irretrievably collapse, threatening a 4-foot rise in sea levels over the next couple of centuries, surged through the news media last week. But many are asking if even this dramatic news will alter the policy conversation over what to do about climate change.

Glaciers like the ones that were the focus of two new studies move at, well, a glacial pace. Researchers are used to contemplating changes that happen over many thousands of years.

This time, however, we’re talking hundreds of years, perhaps — something that can be understood in comparison to recent history, a timescale of several human generations. In that time, the papers’ authors suggest, melting ice could raise sea levels enough to inundate or at least threaten the shorelines where tens of millions of people live.

“The high-resolution records that we’re getting and the high-resolution models we’re able to make now are sort of moving the questions a little bit closer into human, understandable time frames,” said Kirsty Tinto, a researcher from Lamont-Doherty Earth Observatory who has spent a decade studying the Antarctic.

“We’re still not saying things are going to happen this year or next year. But it’s easier to grasp [a couple of hundred years] than the time scales we’re used to looking at.”

The authors of two papers published last week looked at a set of glaciers that slide down into the Amundsen Sea from a huge ice sheet in West Antarctica, which researchers for years have suspected may be nearing an “unstable” state that would lead to its collapse. The West Antarctic Ice Sheet is mostly grounded on land that is below sea level (the much larger ice sheet covering East Antarctica sits mostly on land above sea level).

Advances in radar and other scanning technologies have allowed researchers to build a detailed picture of the topography underlying these glaciers, and to better understand the dynamics of how the ice behaves. Where the forward, bottom edge of the ice meets the land is called the grounding line. Friction between the ice and the land holds back the glacier, slowing its progress to the ocean. Beyond that line, however, the ice floats on the sea surface, where it is exposed to warmer ocean water that melts and thins these shelves of ice. As the ice shelves thin and lose mass, they have less ability to hold back the glacier.

What researchers are finding now is that some of these enormous glaciers have become unhinged from the land – ice has melted back from earlier grounding lines and into deeper basins, losing its anchor on the bottom, exposing more ice to the warmer ocean water and accelerating the melting.

In their paper published in Geophysical Research Letters, Eric Rignot and colleagues from the University of California, Irvine, and NASA’s Jet Propulsion Laboratory in Pasadena, Calif., described the “rapid retreat” of several major glaciers over the past two decades, including the Pine Island, Thwaites, Haynes, Smith and Kohler glaciers.

“We find no major bed obstacle upstream of the 2011 grounding lines that would prevent further retreat of the grounding lines farther south,” they write. “We conclude that this sector of West Antarctica is undergoing a marine ice sheet instability that will significantly contribute to sea level rise in decades to come.”

The region studied holds enough ice to raise sea levels by about 4 feet (Pine Island Glacier alone covers about 62,000 square miles, larger than Florida). If the whole West Antarctic Ice Sheet were to melt, it could raise the oceans about 16 feet.

 Eric Rignot

The glaciers studied by Rignot’s research team. Red indicates areas where flow speeds have increased over the past 40 years. The darker the color, the greater the increase. The increases in flow speeds extend hundreds of miles inland. Image: Eric Rignot

In the second paper, Ian Joughlin and colleagues from the University of Washington used models to investigate whether the Thwaites and Haynes glaciers, which together are a major contributor to sea level change, were indeed on their way to collapsing. “The simulations indicate that early-stage collapse has begun,” they said. How long that would take varies with different simulations – from 200 to 900 years.

“All of our simulations show it will retreat at less than a millimeter of sea level rise per year for a couple of hundred years, and then, boom, it just starts to really go,” Joughin said in a news release from the University of Washington.

Many scientists who’ve been studying the region were already braced for the storm.

“It’s gone over the tipping point, and there’s no coming back,” said Jim Cochran, another Lamont researcher with experience in the Antarctic. “This … confirms what we’ve been thinking for quite a while.”

Cochran is principal lead investigator for Columbia University in Ice Bridge, the NASA-directed program that sends scientists to Antarctica and Greenland to study ice sheets, ice shelves and sea ice using airborne surveys. Much of the data used in the new papers came from the Ice Bridge project.

Tinto, also an Ice Bridge veteran, agreed. “I thought it was pretty exciting, because we’ve all been working on this area for a long time, and that potential for the West Antarctic Ice Sheet to behave in this way, we’ve been aware of it for a long time,” she said. “[It] made me want to get in there and look at the rest of the area, what else is going on.”

And there are still many questions about what’s going on: How fast the ocean that swirls around Antarctica is warming, how those ocean currents shift, and to what extent that is influenced by global warming.

“I have a problem with the widespread implication (in the popular press) that the West Antarctic collapse can be attributed to anthropogenic climate change,” said Mike Wolovik, a graduate researcher at Lamont-Doherty who studies ice sheet dynamics. “The marine ice sheet instability is an inherent part of ice sheet dynamics that doesn’t require any human forcing to operate. When the papers say that collapse is underway, and likely to last for several hundred years, that’s a reasonable and plausible conclusion.”

But, he said, the link between CO2 levels and the loss of ice in West Antarctica “is pretty tenuous.” The upwelling of warmer waters that melt the ice has been tied to stronger westerly winds around Antarctica, which have been linked to a stronger air pressure difference between the polar latitudes and the mid-latitudes, which have in turn been linked to global warming.

“I’m not an atmospheric scientist, so I can’t evaluate the strength of all of those linkages,” Wolovik said. “However, it’s a lot of linkages.” And that leaves a lot of room for uncertainty about what’s actually causing the collapse of the glaciers, he said.

Researchers have been discussing the theory of how marine ice sheets become unstable for many years, said Stan Jacobs, an oceanographer at Lamont-Doherty who has studied ocean currents and their impact on ice shelves for several decades.

“Some of us are a bit wary of indications that substantial new ground has been broken” by the two new papers, Jacobs said. While ocean temperatures seem to be the main cause of the West Antarctic ice retreat, there’s a lot of variability in how heat is transported around the ocean in the region, and it’s unclear what’s driving that, he said. And, he’s skeptical that modeling the system at this point can accurately predict the timing of the ice’s retreat.

But, he added, “this is one more message indicating that a substantial sea level rise from continued melting of the West Antarctic Ice Sheet could occur in the foreseeable future. In the absence of serious near-term greenhouse gas mitigation efforts, such as an escalating tax on carbon, they may well be right.”

“It starts bringing it a little closer to home,” said Tinto. “It’s a significant amount of change, but something we can start planning for. Hopefully [this will] make people stop procrastinating and start planning for it.”

Cochran agreed: The papers’ message is “that … over the next couple hundred years, there’s going to be a significant rise in sea level, and at this point we can’t stop it.” But, he added, “it doesn’t say give up on trying to cut emissions. … [Just] don’t buy land in Florida.”

____________________________________________

For further details on what’s going on in West Antarctica, check out these resources:

The two papers in question:

Widespread, rapid grounding line retreat of Pine Island, Thwaites, Smith and Kohler glaciers, West Antarctica from 1992 to 2011, E. Rignot, J. Mouginot, M. Morlighem, H. Seroussi, B. Scheuchl, Geophysical Research Letters (2014)

Marine Ice Sheet Collapse Potentially Underway for the Thwaites Glacier Basin, West Antarctica, Ian Joughin, Benjamin E. Smith, Brooke Medley, Science (2014)

Armin Van Buuren, Ancient Wood, and Ghengis Khan: This is not your father’s field research in Mongolia

We never expected this. Enkhbat had us hovering at warp speed along the Millennium Road in the northern shadows of the Khangai Mountains. Armin Van Buuren’s A State of Trance filling our rig. We were starting a new project to study the interaction between climate, fire, and forest history in the land of Chinggis Khaan and a silky voice was lifting us higher, “and if you only knew, just how much the Sun needs you, to help him light the sky, you’d be surprised. Do…do…do.do”. We were exhilarated. The Sun was shining. This was not exactly Chinggis’ steppe. But little did we know, we would eventually be chasing his ghost.

 

Image

Byarbaatar & Amy in front of Khorgo, unknowingly about to meet Chinggis’s ghost. Photo credit: Enkhbat.

After about a day’s travel we started passing the Khorgo lava field. Amy asked, “What’s that?” Neil had forgotten about this landmark despite having walked upon it 10 years prior. It is a ~30 km2 lava field with old trees on it. Gordon Jacoby, Nicole Davi, Baatarbileg Nachin, and others had sampled in the early aughts and put together a ca 700 yr long drought record from Siberian larch. Neil relayed this information to Amy and she said that we should sample on it knowing that a 2,000 yr long record in the American Southwest had been produced on a similar landscape feature. We had a tight schedule, but as we drove out to the western edge of the Khangai’s, sampled sites, witnessed a sheep in the dying throes of a brain worm infection, got snowed on, and then sweated in much warmer temperatures, we decided it was worth the time to see what was out there. Little did we know.

By the time we arrived to start sampling, Neil was getting sick (we learned days later that Neil was coming down with tonsillitis) and we were on fumes from some bone-challenging swings in the weather. Amy pushed on during the first day with Byarbaatar and Balginnyam. The found a pile of dead horse bones and couldn’t get the chainsaw running stopping them from acquiring samples from downed, dead trees. It felt almost hopeless.

We summoned our strength the next day and explored a new section of the lava field. Soon after getting out there we starting seeing Siberian pine, a tree Neil hadn’t seen on his first visit and hadn’t been sampled previously at this site. We decided that after our fire history collection we would sample some pine trees just to see what They might have to say.

 

Image

The Logo Tree: The Siberian pine that clued us into the possibility that there might be something extraordinary on the Khorgo lava field. Photo credit: Amy Hessl

As this collection wasn’t priority, these samples sat until late January of the following year. Here is the first email of the discovery (partially redacted for some sensitive language).

 

The sample “locked in and said the inner ring i measured was 1235…whoa! that was cool b/c i started a good bit from the pith…. i race back to me scope and measuring stage…..make mistakes. going too fast. fix the mistakes…..the PITH is 1142!!!!

yes, i can see the yr Chinggis was born. i can see the yr he died. i can see the yrs Mongolia rose to rule Asia!

this has been our Holy Chinggis during the entire Mongolian project.

this is totally hot censored.

neil

ps – i guess we are going back to Khorgo, huh?”

 

Image

KLP0010a – the first sample of Siberian pine from the 2010 Khorgo lava collection to break the 1200s. The pith is 1142 CE (Common Era). Photo credit: Neil Pederson

We secured funding and we went back to Khorgo in 2012 with a bigger crew and one goal in mind – collect more wood.

We cannot believe what we have found.

For centuries, common wisdom held that the Mongols were driven to conquest because of harsh conditions – drought. Our new record, dating back with confidence to 900 CE (Common Era), indicates the opposite. After the unification of the Mongols, Chinggis Khan, you know him as Ghengis Khan, led his army from Northern China in 1211 to the Caspian Sea in 1224 CE. Our new record in PNAS indicates that it was consistently wet from 1211-1225, a period we are calling the Mongol Pluvial (look for an open access version of this paper here or contact Amy or me). No years during this period were below the long-term average, which is a singular rare run of moisture conditions in our 1,100 year long record. Independent tree-ring records over extra tropical Asia also indicate that this period was warm.

On the cool semi-arid steppe of Central Asia, water is life and in those days, water was energy. The Mongol diet is heavily based on the meat of grazers. Their mode of transportation was the short, but Pheidippidic horse. So, for food and for travel, grass is life. Grass is energy. An abundance of moisture would seem to provide the horsepower for the rapidly growing Mongol Empire. The Mongol soldier had five steed at their disposal. With a large army, that quickly translates into a huge herd and a huge need for grass.

Our tree-ring record suggests that the grasslands of central Mongolia were likely productive. They strongly agree with satellite estimates of grassland productivity. Going back in time, then, the trees would suggest the Mongol Empire during its rapid expansion was sitting in a sea of grass, a sea of energy, a potential abundance of life.

That is our hypothesis, anyhow, and something we will test in the coming years with historical documents, environmental records from lake sediments, more tree rings, and ecological modeling experiments.

While this record speaks to a rapid transformation of Eurasian culture during the 13th century, it also speaks about an abrupt transformation in Mongol culture today. Towards the end of our tree-ring record we see a prolonged drought from the end of the 20th century into the beginning of the 21st century. This drought followed the wettest century of the last 11 and occurred during the warmest period of the last 1,100 years in Asia. The abrupt transition in the environmental conditions, a transition that saw hundreds of lakes and wetlands disappear from the landscape, occurs during the transition from a more agriculturally-based economy to a more urban-based economy. These severe conditions, in combination with some harsh winters, killed millions of livestock and are thought to be one trigger of a mass migration of Mongols from the countryside into the capital of Ulaanbaatar.

 

Image

Ulaanbaatar in 2006. The homes on the far hills likely reflect climatic and economic refugees moving from the countryside into the city. Photo credit: N. Pederson

Though we cannot connect this heat drought to climate change (though maybe we kind of can), warming temperatures have stacked the deck towards higher evaporative demand, so even if the amount of precipitation remains the same, high temperatures will generate a more intense drought. That’s what we observed in the early 21st century and based on past moisture variation in Mongolia and future predictions of warming, we would expect to see similar events in the future.

From Armin Van Buuren to Chinggis Khaan to Armin Van Buuren again. We had no clue of how Summer 2010 would light the sky.*

 

_____________

 

* this post was requested by a media outlet so they could have the ‘author’s voice’ on this discovery. That version was ultimately sanitized for your protection. Here it is unadultered.

 

 


Categories: TRL

Long lines and lots of instruments

Sugar - Tue, 03/25/2014 - 11:38
If you want to image the Earth’s crust and upper mantle with seismic data, you need to record the arrival of seismic waves that have propagated down to, in our case, depths of up to ~30 km.  These deep-diving phases travel quickly through the denser, higher velocity rocks of the lower crust and upper mantle, and they arrive back at the surface ahead of shallower phases at long source-receiver offsets (see video below).  




To record these lower-crustal and upper-mantle phases as “first arrivals”, where they are not obscured by the arrival of energy from shallow paths, we use long lines.  Long lines mean lots of receivers and lots of driving to deploy and recover these instruments.  We could have used lots of sources instead, but the blasts we used to get seismic energy into the lower crust and upper mantle in this experiment take a lot of time and money to setup.  Receivers are much cheaper, so we used a lot of them.  (For similar wide-angle/long-offset work at sea, airgun sources are cheaper than putting seismometers on the seafloor, so we use many shots and a smaller number of receivers out there.)


This time-lapse video shows Team 13 of 14 recovering 89 of the 1200 total short-period seismograph stations from where our line crossed Fort Benning, near the northwestern end of the line.



Nathan Miller, LDEO


Deploy in the rain, recover in the sunshine…

Sugar - Tue, 03/25/2014 - 00:32


Weather map during deployment.
When the time came to install our 1200 small seismographs across Georgia at the flagged positions, the rains came….   A lot of rain.  During our first deployment day, we received 1-2 inches of rain, and another wave of rain clouds came through on Day 2 (check out map). Roads that used to be easily passable became mudholes or were flooded with water. All-wheel-drive vehicles and drill rigs alike got stuck, and a few station locations could only be reached on foot. Our hard-working field crew labored in the rain digging holes and deploying seismometers.  Vehicles, equipment and people were covered in the famous Georgia red clay (and other muds and sands of Georgia and northernmost Florida). Adding insult to injury, problems with the programming of some of the instruments meant that we actually had to pick up and redeploy many of them. It was a mudbath.  Nonetheless, our field crew managed to deploy 1200 seismometers across Georgia by Tuesday at sundown. It was an impressive show of endurance, and an inspiring display of positivity given the number of people that were still smiling and upbeat at the end of it all. 
A couple of days later, after our seismic shots, it was already time to pick up the instruments, and the weather changed completely.  The sun shined on SW Georgia, and we picked up almost every last seismometer in just one day under blue skies….  
Donna Shillington, LDEO

Random Pictures from the Road (and otherwise)

Sugar - Wed, 03/19/2014 - 13:43
As a follow follow up to Chastity's post, I thought a few random pictures from the road would be entertaining. I have been part of group 5 and as such responsible for the part of the line that spans from Hahira in the south to just north of Adel.

 South-central part of the seismic line. The yellow line is team 5's section.  We have been in a relatively rural part of Georgia and as a result have not encountered many locals save a few who have stopped to ask if we are ok. However, we have seen quite a few interesting things that are quite out of the ordinary (to me at least).

Friendly Muscovy duck.Rocks in a stream bed with associated pink spongy material (?)
Spanish moss.Linguoid (current) ripples on a washed out road. We have also seen quite a few old abandoned farm houses in various stages of aging...



At least 10-15 dogs were standing guard at this house, including about 8 puppies.

Caroline making some new friends.
All said we have dug 122 holes in team 5's stretch. We have also helped deploy instruments in other sections as well and while doing so have seen others hard at work.

Meghan and Nate getting it done!Along the way the cars have taken quite a beating and have actually held up pretty well. Although there have been a few instances where people got stuck, I think that the people with the toughest job will be the guys that have to detail the cars upon their return...



A more appropriate vehicle (?)And lastly here's a couple more random pictures that I thought were interesting.

The large disparity in fuel grade gas prices.
A ~perfectly leveled geophone (it's harder than you'd think).Hopefully this random selection of pictures was entertaining. Up next we will post about last night's "shots." In the meantime, I can say that they were all successful with varying degrees of excitement. The most important thing is that all of our hard work is being realized as the instruments are recording refractions from buried geology that will help us unravel some of the mystery that surrounds events that happened in this area long ago.

James Gibson, LDEO

Rain, geophones, and animals … Oh my!

Sugar - Tue, 03/18/2014 - 17:15

Chastity Aiken
Georgia Institute of Technology

Flags, Flags, and More Flags - Locating the sites for 1200 instruments

Sugar - Sat, 03/15/2014 - 23:14
Many of the SUGAR field team arrived in Americus, GA on Wednesday to start helping with the massive charge of deploying 1200 seismic instruments along the SUGAR seismic line.  The seismic line spans 200 miles from northwest Georgia to just past the Georgia-Florida border; a 4+ hour car drive from end to end!  Everyone gathered early Thursday morning on the idyllic Georgia Southwestern State campus to meet with the chief scientists and learn about the proper techniques for identifying installation sites for the seismographs (just the first step in installing the instruments).  With neon orange safety jackets, numerous maps, GPS devices, packets of official permitting documents, and heads full of safety precautions the field team split into seven two-person pairs each equipped with their own squeaky clean rental car (though they didn’t stay clean for very long!).  
The fleet of SUGAR rental cars looking clean and shiny before being driven
into the field where they undoubtedly got a little mud on their tires.
Each pair of field assistants was given a segment of the seismic line to drive and flag locations for instrument installation deemed safe both from the seismograph (i.e. dry, firm soil) and the install team (i.e. a safe distance from the road).  Given the shear distance of the seismic line, teams found themselves amid diverse backdrops from rolling farmland with overly friendly cows to buzzing residential neighborhoods to sandy stretches flanked by towering groves of Ponderosa Pine trees. 
Antonio placing a flag and using a GPS device to note the location where a
seismograph will be installed amid the sandy surroundings of a Ponderosa Pine farm.
Every team was able to flag all their sites within just two days leaving us the luxury of a sunny Saturday morning free for exploring more of our beautiful Georgia surroundings.  Next up is the actual task of installing the 1200 seismographs which will involve twice the people, six more (temporarily clean) vehicles, and of course countless exciting adventures from the field.  Happy (almost) St. Patrick’s Day from Americus!
A picturesque county road near Jasper, FL along which instruments will be deployed.
-- Natalie Accardo, LDEO





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