From the Desert to the Rainforest: Heading to Alaska

June 19th, 2012

(Guest Blogger: Lauren Vargo)

From the desert to the rainforest, several other Wooster geologists, Dr. Greg Wiles, Jenn Horton, and myself, traveled to southeast Alaska. The main goal of the trip was to investigate Adams Inlet in Glacier Bay National Park and Preserve where we planned to use tree rings and stratigraphy to gain a more detailed geologic history of the Inlet.

However, our journey started (and ended) in Juneau with hikes up to and around Mendenhall Glacier. On our first day in the capital city, we took a leisurely hike up to the Glacier where we ate lunch near the terminus and saw first-hand glacial calving.

 

Jenn and I at the start of our hike up to Mendenhall Glacier

 

Jenn and I with the Wooster flag at Mendenhall Glacier

 

On our last day in Alaska, instead of hiking to the Glacier, we hiked up to the snow near tree line. We cored mountain hemlock trees for samples to send to a Swiss group to do isotope research, as well as to update our existing chronology.

 

Jenn and I above Mendenhall Glacier, hiking up to tree line

 

Coring a mountain hemlock tree

 

 

In between these excursions in Juneau, we traveled to Adams Inlet, our main destination, to research and collect data for our Independent Studies. We were lucky enough to have beautiful, sunny weather on our first day in the field.

 

A map of Glacier Bay National Park, with Adams Inlet marked with the red star

Jenn and I on our first day in Adams Inlet, enjoying the sun and clear view of the mountains

 

Watching the sunset on our first night in the field

 

Jenn and Dr. Wiles with all of our gear and the kayaks

 

In the Inlet, we looked at and took careful notes of the stratigraphy of several different valleys. We spent a good deal of time using the ice axe to clear off weathered and eroded sediment exposing varves (annual layers of clay and silt deposited in lakes) and other layers, usually of sand, gravel and glacial diamict.

 

Glacial lake varves we uncovered in one valley

 

 

Jenn and I sitting on top of glacial lake varves with deltaic sediment and mountains in the background

 

Dr. Wiles clearing off sediment to expose layers of varves and oxidized sand and gravel (also, notice the mud slickenlines from mudslides in the area)

 

Layers of clay alternating with sand and gravel exposed by the river cutting into the sediment

 

A closer view of clay layers within oxidized sand and gravel

 

 

In addition to the stratigraphy, in one valley we saw an amazing matrix supported rock flow.

Check out the video here.

And a second video here. 

 

Alaska 2011

July 6th, 2011

Guest Blogger: Sarah Appleton

Wooster Geology takes its students all across the globe and this time they have traveled to the distant land of Glacier Bay National Park and Preserve (http://www.nps.gov/glba/index.htm), Alaska, for a better look at the sedimentation, ancient forests, and glacial processes at work there. Three of Wooster’s finest, Dr. Greg Wiles, Joe Wilch (Junior), and Sarah Appleton (Senior) ventured out into the Alaska back-country for a chance to study at three amazing sites within Glacier Bay; Wachusett Inlet, Casement Glacier, and Mount Wright. Each site gleaned a tidbit that falls into the overall complex story of glaciations and ice melt throughout the Holocene time period.

A map of Glacier Bay National Park and Preserve, Alaska.

The team of Wooster geologists set out on the 14th of June for their wilderness study aboard the proud vessel, The Capeland. Captain Justin Smith and the Capeland took out five brave scientists ready to brave the wilderness in order to learn more about the natural world around them.

Captain Smith standing on the front of the Capeland as they are getting ready to leave.

 

Our team of Wooster Geologists we accompanied out into the field by two noble scientists from the University of Birmingham in the United Kingdom, Meagan and Ed. They were out studying the effect of wood in the stream on the amount nitrogen present and the presence of different microbial organisms in the water and soil of the stream. They brought with them their brilliant sea faring skiff, Porcupine, (which they affectionately refer to as Porkey) who blazes through land and sea.

Porkey the skiff, blazing a trail on land and sea.

The Capeland dropped both groups of dedicated scientists off at their first campsite, a large outwash fan near the head of Wachusett Inlet. We dropped off our gear and got right to work. The first order of business was to investigate the Plateau Glacier, an ice remnant across the fjord near to Megan and Ed’s site of study. They lead us bravely through the maze of alders to their study site below two small lakes, and pointed us upstream toward the source of the water, the glacier. We hiked up and made our way out of the alder and brush and onto the glacial outwash plane. A cool breeze blew around the glacier, which at first glance appeared to be gone. On a closer inspection we discovered that the glacier was still there, buried in sand and gravel.

Platueau Glacier, an ice remnant, buried in sand and gravel with the melt water from the ice flowing out in front.

We approached the glacier enthusiastically ready to investigate and set about exploring the ice. There were caves in the ice where the glacier had melted and many little braided streams carrying the silty water away from it. All too soon it was time to travel back to meet our fellow scientists and travel back across the fjord. We beat our way back down through the brush and alder to the shore where we met Megan and Ed, who sailed Porkey back across the water to our camp. Once ashore we set up camp and made dinner. It was a great first day in the field.

Sarah Appleton and Joe Wilch exploring Plateau Glacier ice remnant.

Wachusett Inlet: The Unnamed Valley

Day two began bright and early, with oatmeal and hot chocolate or coffee. It was time for the real work began. The plan of attack was to tackle the right side of the recently deglaciated unnamed valley whose base we were camping on. The hike began through a few alders and quickly emerged onto a more tundra like moraine that consisted of large boulders covered in lichen, moss, and dryas. Carefully, we picked out way up the ridge keeping close to the thundering outwash/melt water stream. We walked along the edge inspecting the valley below. What we saw was very promising, large freshly eroded walls of sediment features that helped to tell the story of the past glaciations and deglaciations. We pause frequently to photograph the left wall which we could see as well as to take photos of our beautiful surroundings. As we could, we climbed down into the valley and began to work along the wall mapping out the different sediment layers and taking photographs. We hiked well up into the mountain until we reached a point where the stream divided into two where we took a break for a snack, rest, and more photographs.

Sarah Appleton and Joe Wilch taking a break high on the mountain overlooking Wachusett Inlet.

We made our way back down the valley this time working the other side of the large moraine that was present. The hypothesis we formed was that this moraine was part of the small unnamed glacier at the top of the mountain. Using the same method as before, our team worked back down the mountain looking at the sediment featured in relation to the in situ forests we saw. Once back at camp we made dinner and plans for our next day’s work. Megan and Ed were kind enough to offer us a ride around the large outwash stream the next morning on their way across the fjord so that we would be able to work the other side of the valley. The outwash stream was a bit too large to be crosses on foot except for at low tide. Our return would be at low tide so we planned to attempt to cross the stream on the way back to allow us more freedom while working on the left side of the valley.

Sarah Appleton and Joe Wilch climbing/sliding down the slope for a better look at some in situ tree stumps.

The hike up this side of the valley covered the same type of terrain that we saw on the other side of the valley. Our group crashed through the alder and brush up the opposite side of the moraine to the tundra like section and again kept to the edge of the stream to get a good view of the valley walls. We hiked to the site use below the moraine as we planned the previous day and began to work our way down the valley mapping the different sediment features in relation to the in situ tree stumps. The biggest mystery was what layer of sediment the trees we rooted into. As we worked we pondered this and then we spotted it, a stump that was rooted upright in a layer of dark organic soil. This was the key to being able to figure out more about the first site we were looking at. It was an awesome breakthrough.

Joe Wilch standing above the tree rooted in the organic layer of sediment.

We climbed out of the highest bowl and began to hike down to the second and third bowls repeating our procedure for the first one. Overall it was a productive day! Once we had all the data we thought we could glean from the site for the day we hiked back down the mountain to camp. We were almost to camp the only thing keeping us from it was the raging outwash stream. Dr. Wiles lead the way across the stream carefully picking out a good way. Joe followed once Dr. Wiles had made it across. Finally, Sarah attempted to cross the stream…SPLASH! Down she went for her first swim of the trip. Fortunately, camp was very close so dry clothes were not far away though on the warm Alaskan day the swim was quiet refreshing. This wrapped up our work in Wachusett Inlet.

Joe Wilch crossing the raging water of the outwash stream.

On June 17th the team rose to a bright sunny if a bit cool day. After breakfast Megan and Ed took Porkey up the Inlet to attempt to make radio contact with the outside world so that we would know when the Capeland was arriving to pick us up for our move to Forest Creek and Casement Glacier. As they drove out of sight we began to pack up gear and lay wet gear out to dry in the sun on large boulders. We helped them load their boat and waved them off. After they had left we moved all of our gear down the beach to the shore and settled in for lunch, naps, and time to update our notebooks. We waited patiently for the Capeland, stirring once to move our gear up above high tide as the water came in before the boat arrived. The Capeland dropped us off at Forest Creek, a former outwash stream of Casement Glacier and we set up camp in two beach meadows.

Dr. Wiles setting up camp in the second beach meadow filled with strawberry flowers.

Casement Glacier

Once camp was established and we had helped Megan and Ed unload their gear we decided to make a run up the short trail to Casement Glacier to investigate what we would spend the next three days studying in depth. It was a little bit later in the day about six o’clock  in the evening and the outwash was only 3 km away from camp. We began our hike chatting about what we might find once we arrived at the glacier. Beating through a row of alder and what luck! We found a moose trail! The moose trail appeared to go to the glacier, so we began to follow the way of the moose. The moose trail was fairly easy to follow until we arrived to the near end of our journey, where our moose trail swung to the right and away from our goal. We were about two and a half hours into our hike, so much for a short trail! The three of us crashed through a thick bunch of alder and emerged on the endless outwash plain of Casement Glacier.

The outwash plain goes on and on my friends, some people started crossing it not knowing what it was, and it is the outwash plain that never ends!

In the distance we could see a corner of bedrock and Sarah decided that we should walk out to peek around it. That turned out to be a bad decision. The outwash plain and the large section of bedrock tricked the eye and were much farther than they appeared. The three geologists peeked around the corner, caught their breaths, and turned around to head back to camp and dinner.

Casement Glacier

One small glitch occurred, however, once you are in the alder it all tends to look exactly the same and so our brave scientists got turned around looking for the way of the moose. After an hour or so of circling around the alder the team finally located the moose trail and ran down the mountain to avoid getting caught in the dark, which in an Alaskan summer doesn’t happen often. Finally, the team stumbled out of the alder and back onto the beach. We were bushed and grabbed a bagel for dinner and crawled into our tents and out of the killer bugs.

Joe Wilch and Sarah Appleton standing in front of Casement Glacier.

The next day we stiffly got out of our tents, ate breakfast, and gathered our gear. We set out again on the way of the moose crossing the lakes of the killer giant toads and battling the flesh eating mosquitoes through the moose sandbox and past look out rock. We kept our heads down and practiced the Alaska wave. The Alaska wave can be done in a wide variety of ways, some people prefer to use the back and forth method, others wave with a willow branch, and some swat in a violent fashion. Trudging onward the scientists finally reached the land of the endless outwash plain. They put their heads down and continued to march. Eventually, they reached the corner of bedrock and two large boulders were chosen as a suitable site for a rest and lunch. We continued our procedure that we started in the valley at Wachusett Inlet taking pictures and looking in depth of the sediment in relation to the in situ stumps along the wall of the exposure.

Sarah Appleton standing on the lower tier of a buried forest that is topped by a layer of glacial till.

The sediment features were much less clear at this site most of what we saw was glacial till and bedrock though we did see a section of sediment that appeared to be lake sediments with the trees rooted just below the layers causing up to hypothesize that the trees were growing when a lake came in and flooded them causing them to die and then be run over by a glacial advance. Joe and Sarah hiked up the outwash to further investigate the site. They walked up to the margin of the glacier and discovered even more buried forests up around the corner of the glacier. These were left to be tackled another day, and we made the journey back across the vastly different lands to our base camp.

Joe Wilch pondering the mysteries of Casement Glacier.

Wolf Point

The next day, everyone was exhausted from the brutal hikes to Casement Glacier so we opted to work in a different site to mix it up and allow our legs a chance to heal. Our camp mates, Megan and Ed, said that they saw some old wood in their site, so we decided to go and investigate. Wolf Point is a nice little stream that was across Muir Inlet from our camp. It was an easy walk back to through the alder. The stream was much bigger than the one at their previous site, and required frequent crossing. The first thing we did when we got to the stream was too investigate the old wood. There were several pieces in the stream itself being beaten by the water. After stopping to look at the wood we continued up the stream to catch up with Megan and Ed for lunch. We were nearly there when another stream crossing came up. Dr. Wiles picked his way across it and Sarah was following just behind when SPLASH! Swim number two. She stood up then scurried across the stream. The dry clothes were a relief as was the fact that the rain had finally stopped.

Some old wood mixed in with modern wood caught in the stream.

After lunch we opted to stay and help Megan and Ed with their experiment. We helped them get their water samples and soil samples for the day learning about what they studied and their methods for doing so. All too soon we had completed another field day and it was time to head back to camp. We began to trek back to the beach and were doing well until we came to another stream. Then SPLASH! Sarah’s third swim of the trip. Apparently, you must be so tall to cross the stream and she was just not big enough or more likely needs more practice. This time fortunately, Sarah did not get too wet.

Megan and Ed taking a water sample while Sarah watches in the background.

We pushed onward to the beach and the boat which was floating in the water patiently waiting on our return. Our crew climbed into the boat and sailed back to the beach. Throughout the day we had talked about dinner and decided that we would have quesadillas cooked over the propane stove. We were all really looking forward to this meal. Sarah put in charge of cooking them paired with chicken flavored rice. It turned out to be a great meal that everyone enjoyed while standing around a campfire on the beach as the sun peaked through the gray overcast sky to set behind the mountains. It was a good and relaxing day learning about other research that was done in Glacier Bay.

Large eagle drying out on a small twig.

Bear/Casement

The next day was our last full day at the Forest Creek camp we were set to leave the next morning for Sandy Cove. With the daunting hike to Casement Glacier looming over us we took out time getting ready this morning thought hoping to make somewhat of a decent start. We ate breakfast and gathered our gear that we would need for the day. Once we were ready we piled it up on the beach and went to help get Porkey back into the water. With the five of us pushing the skiff nobody was really watching our surroundings as the metal boat scraped its way down the beach. We successfully managed to get the boat into the water and had turned around to pick up the rest of Megan and Ed’s gear and put it back into the boat. Megan saw it first and called BEAR!

The bear that crept up on us as we pushed Porkey back into the water.

We all froze and began to scan down the beach looking for the bear. Most of us missed it at first because we were looking out down the beach instead of close to us. The bear was less than 100 meters from us and walking right along the shore in our direction. This is one of those moments all the bear safety lectures kick in. We grabbed the remaining gear and grouped together on the beach to make ourselves look bigger. We yelled and clapped our hands or waved trying to get the bear to move away. This bear did not look so good. His fur was dull and shedding out and he was thin. He seemed less than interested in us but gave us a couple more meters space as he walked around us and continued down the shore. He paused every now and again to turn over a good size rock in search of eels to snack on. He took so long and was, fortunately, ignoring us that we began to joke that he was turning over every third rock just to annoy us. Megan and Ed snapped some pictures while we watched and waited for the bear to move on.

The bear as he continued down the beach.

The Wooster team began to make plans on the best way to start our hike that did not encroach on the bear since he was going in the same direction down the beach that we would need to head once it was safe. The bear made it down to the corner of the beach and we decided it was safe to creep back to camp and gather our gear to leave. Our team made it part way up the beach when the bear jerked around and came a few steps in our direction. We froze and looked at each other. The bear apparently had forgotten all about us until we moved again. He took a few more steps in our direction and we quickly walked back down the beach to regroup. Unfortunately, the bear was headed for our camp. We all dashed back to camp and grabbed pots and pans to scare the bear off and protect our turf. This is park policy so that the bears do not get too used to humans and become a more dangerous problem. The bear still did not run from us but did wonder away to the nearby meadow to snack on the grass there. Periodically, he would stand up on his hind legs and look at us over the brush. Finally, he moved on to do whatever bears do in the late morning.

And under rock number three? More eels!

With our last day burning down we took off for Casement Glacier, again following the way of the moose. The hours passed quickly with everyone more on guard looking for bears and any other wildlife that was certainly lurking just beyond the next bush, rock, or tree. Eventually, we plodded to the perceived safety of the endless outwash plain where you can see forever in all directions. We passed by a small kettle lake and suddenly heard something crashing through the alders on the side it. A moose charged out of the brush and galloped away from us. It was neat to get to see one of these animals so close up and a relief that it chose to run away unlike the bear who was content to simply ignore us. We then moved on to lunch in our usual spot with everyone remaining a little jumpy. Before long, it was time to get back to work.

We hiked further down the outcrop and around the side of the glacier. We began to work out way back looking at the stratigraphy in relation to the tree stumps that we saw in place. There were six forests still in place in relation to the small section of lake sediment that we saw there. It was much smaller than the section we studied in Wachusett Inlet. We worked our way back down away from the glacier going over each of the sections. All too soon it was time to return back to camp and we took off on the brutal hike back.

McBride Glacier

The next day was bright sunny and clear giving us an excellent view of the beautiful coastal mountains across from our camp at Forest Creek. We got up ate breakfast and quickly tore down camp to be ready for the arrival of the Capeland which was supposed to arrive at 10 am and we had a bit of a leisurely morning. We loaded our gear and then we headed to McBride Inlet with a team that was tearing down a climate station there.

Three Wooster geologists mugging for the camera in front of McBride Glacier.

McBride Inlet is the home of a tidewater glacier with the same name. We hiked into the glacier after the Capeland dropped us off along the steep shoreline. The shore and inlet were littered with icebergs of all sizes that we all enjoyed taking photographs with and of. It took about an hour to hike in to the knob where we could see the glacier. Here we admired the glacier and ate our lunches while Nick Wiesenberg and Dan Lawson got to work tearing down the climate station. We did not get to see any glacial calving while we watched the glacier just admired and enjoyed the view. Instead, we watched the seals down in the inlet sun bathing on the icebergs and the Kittiwakes swoop and fly around their nesting site on the opposite cliff.

Seals sun bathing on icebergs in McBride Inlet.

Once the team had torn down the climate station we headed back to the beach and the waiting Capeland pausing to occasionally take pictures of the ice. Once back on the boat we swung by the Forest Creek camp to pick up Porkey and then we were off to Sandy Cove raft to drop of Dr. Wiles and Sarah Appleton who would be hiking up to a refugia site on Mount Wright to do some coring of the old trees there. A refugia is a forest of trees that were not run over during the last glaciations and are very old in age relative to the other trees which are moving back into the bay from the coast.

Shopping for icebergs?

After sleeping in a tent for eight days the Sandy Cove raft seemed luxurious with its bunk beds and small kitchenette. The rest of the day was spent on the raft relaxing and preparing for the long days hike up onto the ridge behind Mount Wright.

Sandy Cove Raft!

Mt Wright/Sandy Cove

Early in the morning Dr. Wiles and Sarah Appleton began the climb up the ridge to the Mount Wright refugia. The hike was long and intense walking first through the lowland forest, crossing a bog, and then crashing through the brush on the way up the mountain to the old growth forest. The day was bright sunny and clear which made for beautiful conditions to hike.

View of Beartrack Mountain from the back porch of the Sandy Cove raft.

We hiked up to the upper tree line for a better view. Once at the top we paused to take in the beauty that surrounded them and pictures.

View from the top of the third ridge on Mount Wright!

We sat for a time and rested, overlooking the ground just covered and spotted something gray darting among the patches of green in the snow. Once the gray blur paused to sniff our tracks and we realized it was a wolverine. The wolverine began to follow our tracks back the way we had come. This was sort of frightening to see it track us and to walk down and see its tracks next to ours.

The Wolverine tracking us back the way we had come.

We headed back down to the refugia site and got to work coring trees. Several hours were spent coring trees in the beauty of the forest. All too soon it was time to slide back down the hill through the raspberries and devils club to the shore where we had parked Porkey on loan to us from Megan and Ed. We rowed across the water to the raft and dinner.

The refugia on the ridge behind Mt. Wright in Glacier Bay National Park and Preserve, Alaska.

The next day we laid out our gear to dry and updated our field notes from the day before. The Capeland picked us up and took us back to Gustavus where we loaded our gear up and went to research housing. There we unpacked our personal belongings, took a much needed shower, and met the other scientists staying there as well. We then had a spaghetti dinner courtesy of Nick and went to bed.

Mendenhall

After a great time in Gustavus it was time to fly back to Juneau for a day and a half before we flew home. Saturday morning we boarded Fjord Flying and flew to Juneau.

The plane in which we returned to Juneau.

Once in Juneau we helped to unload our gear from the plane and out into the rental car. From there we went to our favorite Juneau eatery, Donna’s, for breakfast for lunch. After a great and satisfying meal we went to find a place to camp at the Mendenhall campgrounds. Nick and Dr. Wiles carefully picked out the perfect campsite for us to stay. It was lovely with the lake just behind us through the trees. We set up out tents all in a row and set off on a hike to the Mendenhall Glacier!

Mendenhall Glacier in Juneau, Alaska.

We chose to hike the west side trail and go out onto the glacier. The hike was a breeze after all the back country hiking we had done in Glacier Bay National Park and Preserve. There was a trail that had good footing and a hand rail when the trail narrowed on an edge. After hiking for a while we made it to the glacier. The cool glacier breeze was refreshing as we cooled off from our hike and explored the glacier, the surrounding bedrock, phyllite, and glacial till. Within the glacial till we were able to find old logs that had been run over by the glacier in the past. We began to wonder about their age and their story. Another student’s future IS???

Sarah Appleton and Nick Wiesenberg hiking on Mendenhall Glacier.

Once our curiosity had been thoroughly sparked we began to hike back down the trail to camp. That night we ate a wonderful meal prepared by Nick over the campfire of bratwursts, complete with onions and green peppers, potato chips, and orange juice followed by a delicate desert of ‘smores made with peanut butter cups or regular chocolate depending on your taste. A great day indeed!

Sarah Appleton and Nick Wiesenberg exploring the Mendenhall Glacier.

Non-stationarity in climatic response of coastal tree species along the Gulf of Alaska (Senior Independent Study Thesis by Stephanie Jarvis)

April 15th, 2011

The crew in their XtraTufs. From L-R: Stephanie, Deb, Dan, and Greg.

Editor’s note: Senior Independent Study (I.S.) is a year-long program at The College of Wooster in which each student completes a research project and thesis with a faculty mentor.  We particularly enjoy I.S. in the Geology Department because there are so many cool things to do for both the faculty advisor and the student.  We are now posting abstracts of each study as they become available.  The following was written by Stephanie Jarvis, a senior geology and biology double major from Shelbyville, KY.  Here is a link to Stephanie’s final PowerPoint presentation on this project as a movie file (which can be paused at any point). You can see earlier blog posts from her field work by clicking the Alaska tag to the right.

For my IS field work I traveled to Glacier Bay National Park & Preserve, Alaska with my geology advisor, Greg Wiles.  Our field crew also consisted of Deb Prinkey (’01), Dan Lawson (CRREL), and Justin Smith, captain of the RV Capelin.  My focus was on sampling mountain hemlock (Tsuga mertensiana (Bong.) Carrière) at treeline sites to study climate response and forest health using tree ring analysis.  While in Glacier Bay, we also sampled interstadial wood (from forests run over from the glaciers that were now being exposed on the shore) and did some maintenance work on Dan’s climate stations throughout the park.  Back in the lab, Wooster junior Sarah Appleton kept me company and helped me out with some of the tree-ring processing, as did Nick Wiesenberg.

The view from treeline.

An interstadial wood stump, in place. The glacier ran over this tree and buried it in sediment, which is now being washed away.

Site map

I ended up processing cores from only one of the three sites I sampled this summer (the others can be fodder for future projects!).  In addition, I used data from several other sites sampled in previous years.  My data consisted of 3 mountain hemlock sites forming an elevational transect along Beartrack Mountain in Glacier Bay (one described by Alex Trutko ’08), 3 mountain hemlock sites at varying elevations from the mountains around Juneau, AK, and 2 Alaskan yellow-cedar sites (Chamaecyparis nootkatensis (D. Don) Spach) from Glacier Bay used by Colin Mennett (’10).   My purpose was to look into the assumption of stationarity in growth response to climate of trees over time and changing climatic conditions.  According to the Alaska Climate Research Center, this part of AK as warmed 1.8°C over the past 50 years.

Tree-ring base climate reconstructions are important in our understanding of climatic variations and are a main temperature proxy in IPCC’s 2007 report on climate change.  Climate reconstruction is based on the premise that trees at a site are responding to the same environmental variables today that they always have (thus, they are stationary in their response), allowing for the reconstruction of climatic variables using today’s relationship between annual growth and climate.

Greg coring a tree at treeline.

Crossdating using patterns of variations in ring width.

Temperature reconstructions using different proxies, including tree-rings, from the Intergovernmental Panel on Climate Change’s 2007 report.

Recent observations, such as divergence (the uncoupling of long-term trends in temperature and annual growth) and worldwide warming-induced tree mortality, suggest that this assumption of stationarity may not be valid in some cases.  Using mean monthly temperature and precipitation data from Sitka, AK that begin in the 1830s, I compared correlations of annual growth in mountain hemlock to climate at different elevations over time.  My results indicate that mountain hemlocks at low elevations are experiencing a negative change in response to warm temperatures with time, whereas those at high elevations are experiencing a release in growth with warming.  Low-elevation correlation patterns are similar to those of lower-elevation Alaskan yellow-cedar, which is currently in decline due to early loss of protective snowpack with warming.  An increasing positive trend in correlation to April precipitation and mountain hemlock growth indicates that spring snowpack may be playing an increased role in mountain hemlock growth as temperatures warm.  The high elevation mountain hemlock trends suggest the possibility of tree-line advance, though I was not able to determine if regeneration past the current treeline is occurring.  Tree at mid-elevation sites seem to be the least affected by non-stationarity, remaining relatively constant in their growth response throughout the studied time period.  This indicates that reconstructions using mid-elevation sites are likely to be more accurate, as the climatic variable they are sensitive to is not as likely to have changed over time.

Cedar chronologies (green lines) compared to temperature (brown line). Bar graph represents correlation coefficients between annual ring width and temperature, with colors corresponding to labels on the chronologies (orange is lowest elevation PI, blue is higher elevation ER). Asterisks represent significant correlations. Note that the relationship has changed from being positive at ER during the Little Ice Age to negative by the second half of the 20th century.

Mountain hemlock chronologies (green lines) compared to temperature (brown line). The top graph is of the Glacier Bay sites, the bottom is of the Juneau sites. Red represents the low elevation sites, green the mid-elevation, and purple the high elevation. Note that the low elevation sites are decreasing in correlation as the cedars have, while the high elevation sites have experienced a release in growth with warming.

 

Thraspberry Thrashing

June 14th, 2010

All of us by the Bartlett River.

guest blogger: Stephanie

It’s been a full week! On Monday, Justin (the captain) and Tom (captain of another boat who Justin was training for the Capelin) took all of us around to climate stations Dan maintains throughout the park to offload data and repair any snow/bear damage. We went up the West Arm and saw several beautiful glaciers. We stayed that night at the Russell Cove raft, a raft for researchers (not all of us fit…so we got to sleep on the island!). Greg found a new toy.

Greg, Deb, & Dan hard at work at a climate station.

The well-used "ursabahn" by one of the stations.

The Wooster flag in the West Arm.

Free ice! Justin nets a couple small icebergs for the cooler.

Home sweet home--the researchers' raft.

A new toy for Greg.

Tuesday the Capelin’s unidentified mechanical problems seemed to worsen, so the day was called off and Greg and I were dropped off at Sandy Cove. As we drove in, we scared a moose off the coast, and not long after a black bear came rolling long grazing on the grass. We got a late start (and subsequently a very late finish…) up Mount Wright. After about 4-5 hours of nothing in view but thorny brambles and devil’s club (which I am still picking out of my hands), we finally made it to the top of one of the ridges to find a beautiful landscape of karren limestone outcrops, snow, and mountain hemlocks. We made a quick side trip to the nearest top (~3000 ft) just for fun, looked down on a goat (always a good sign), and then got to work. It was 8 or 9 before we finished sampling, so we took an express route down and had a nice walk in the almost dark along the coast (every boulder looked like a bear…). Along the way we came across an awesome tufa waterfall, where the water was coming out through the limestone and precipitating (like in a cave). Unfortunately, it was too dark to get a good picture.

A welcome view.

Mushrooms! In the snow!

Steph at 3000 ft.

Greg at 3000 ft, with the Beardslees in the background.

The next day we walked along the river looking for interstadial wood (trees that were run over by glaciers and then buried). We didn’t find any, but we did find a good lunch spot, where we could ponder over the delta sediments the stream was cutting through and later piece it with the lake sediments farther up. The glacier, when it came down to the mouth of this valley, had blocked it off and formed a lake here.

An interesting outcrop (I know, I know, no scale. I think the bushes are ~4-6 ft.)

A relaxing lunch (we earned it!).

A nicely stuck boulder.

Meanwhile, Deb, Dan, and Justin were trying to get our boat situation worked out. The Capelin was pronounced ok, but quickly showed it wasn’t, and they were able to negotiate using a different one. The Petrel was much speedier than the Capelin, but required a ladder to get in and out on shore and didn’t like rough water very much. They met up with us at Sandy Cove on Wednesday and joined us in the ranger raft that was there (much like the researchers’ raft, without the star wars sheets…).

Thursday was another, very buggy, climate station, and then Gieke Inlet, where they had some radiocarbon dates on interstadial wood going back 3000 yrs. The particular outwash we were in had, according to Dan, been formed in a couple days of rain in November of 2005, so it was pretty rich with wood being weathered out.

Dryas patches in Gieke Inlet--the first plant to move in once the glaciers recede.

We came back to Gustavus Thursday night (showers!!!), and went out with Tom on Friday, again looking for interstadial wood. We went to Willoughby Island, where we found some really cool layers of peaty organics under gray silt/clay under gravely glacial sediments. Bad weather rolling in made it an early day, and that night we went to open mic night at the pizza place, where I realized just how much talent could be squeezed into a little town like Gustavus.

A stump (spruce, we think) in growth position at Willoughby Island.

Dan left Saturday morning, and more bad weather resulted in the calling off of our plans to go to Pleasant Island to look at Cedars stripped by the natives (the Tlingit). Instead, we went kayaking in the Beardlees and got hammered by some rain and hard wind. Much fun! The night was topped off by our housemates, sea otter researches with USGS, bringing back a huge king salmon they had caught (they forced me to try some…). Yesterday we made the trek up Excursion Ridge, where we got to see the new hydroelectric dam that is now powering Gustavus and do some slip and sliding on the steep snow patches. Got lots of good samples, and came back to find out the otter folks had caught another king salmon. They happily shared again 🙂

The dam that powers Gustavus.

Lunch...I'm sensing a pattern here...

Flowers! On the way up we came across several meadows and bogs.

A good view of Gustavus.

This morning, it’s back to Juneau. Mendenhall glacier is in the plans, as is a look around town. It’s back to Wooster on Wednesday.

Beartrack Mountain

June 6th, 2010

guest blogger: Stephanie

On Friday Justin, Capt. of the Capelin, dropped Greg and I off at Beartrack Cove. We hiked up (straight up!) to the Repeater Station (used for the park radio station), where we set up camp and then made our way a little further up to our study site. We cored a few trees that night, then melted some snow to make some delicious navy bean soup (courtesy of Fred Meyers in Juneau) and hot chocolate, and turned in. An early morning start to finish up the bulk of our sampling there, then it was back down (which didn’t take nearly as long as the up had, but resulted in much more soreness…) to meet the Capelin again. On the way back to Bartlett Cove, where the visitor station and park headquarters is, we saw sea lions, sea otters (one riding our waves on its back), whales, puffins, and porpoises (I didn’t get any good pictures of these, but I will try next time!).

The Capelin

A view from the way up. The line is where cloudy glacial runoff is meeting the incoming tide.

Beartrack repeater station

Fresh bear tracks on the way up to the site.

Sun coming through some clouds over the water.

Sun coming through the clouds over the water.

Where Greg would like to go... There is a tiny white speck up there--it's a goat!

The Beardslee Islands. You can see the repeater station below Greg.

Hanging a bear bag.

Soup!

and cold feet...

Mushrooms!

A little later and we would have some yummy strawberries.

A barnacle encrusted snail.

Beartrack from the boat. I think we were just the the left of that first small snow chute on the right.

We met up with Dan when we got back, and Deb Prinkey, ’01, a high school teacher in Mt. Vernon. Greg and Dan are finishing up a report for NSF right now, then it’s a short hike today and back out tomorrow.

Up to Alaska

June 4th, 2010

guest blogger: Stephanie

We arrived in Juno last night a little past 10 PM local time (that’s 2 AM for us…) after a long day of traveling, to be greeted by stuffed bears in the airport (awesome!). After spending a night in the lovely Breakwater Inn, we had an amazing breakfast at Donna’s, swung by the Mendenhall glacier in the Tongass National Forest, and then waited in the airport for Dan Lawson, of CRREL (Cold Regions Research and Engineering Laboratory).

The Breakwater Inn

Mount Juneau

The Mendenhall glacier

The "stream" at the hatchery. When spawning time comes, the salmon hatched here return.

Shopping followed, as did lunch and a quick trip to the salmon hatchery. Then it was back to the airport to catch our flight to Gustavus, which provided us with some awesome views of the inlets and mountains in the area.

Our plane!!

A cirque, a basin formed by a glacier, seen from our plane.

Once in Gustavus, we went on into Glacier Bay National Park to the headquarters to plan for the next few days and learn some bear safety tips. Tomorrow, it’s to the field!

A Day on Pleasant Island

July 27th, 2009

Tree
The Woo crew in front of one of the larger cedars we found.

Today we took a skiff over to Pleasant Island to core some older cedars. Our guide and captain for the day was Wayne, an archeologist in the area. We found many huge and old cedar trees after a relatively easy hike to the site. Colin managed to get many cores to bolster his chronology for his IS.

Skiff
Dr. Wiles and Wayne help secure the skiff after landing on Pleasant Island.

Coring
Wayne looks on as Dr. Wiles and Kelly core a large, old and dead cedar. The cedar remain standing long after death.

Also interesting was a dendroarchaeological point of interest: we found several cedar that had their bark stripped by (we think) the Tlingit. Colin’s careful analysis will help us to know the year it was stripped for sure.

Adze
A dead yellow cedar that has had its bark stripped. Wayne thinks the markings were likely made by an adze.

Cedar Adventure to Excursion Ridge

July 26th, 2009

Intro
Kelly and Colin standing on one of the lower ridges near Excursion Ridge.

Today we hiked up Excursion Ridge to collect yellow-cedar samples for Colin’s I.S. On the trek up to the cedar stand, we hiked up the road and passed the dam used for the Falls Creek hydroelectric project. They plan to harness the power of Falls Creek to provide summer power to Gustavus.

Dam
The dam on Falls Creek. They regulate the flow of the creek to provide power while still allowing enough water for the fish. It is a controversial project due to questions on power provided versus environmental impact.

The day was uncharacteristically beautiful, and the expedition turned out to be fruitful. We collected samples from 43 yellow-cedars, with at least two samples from each tree. While at the site, we also collected samples from lodgepole pines dominating the meadow to satisfy our scientific curiosity. All in all a very productive day.

Coring
Colin places a core into the straw after extracting it from the tree.

Meadow
The meadow located at the top of the sample site, dominated by lodgepole pines and covered by arctic cotton.

Lunch
Dr. Wiles and Kelly walk through the meadow to the lunch site.

News from the North

July 25th, 2009

Colin and Kelly standing in front of Mendenhall Glacier. Last year, the ice was where they are standing.

Colin and Kelly standing in front of Mendenhall Glacier. Last year, the ice was where they are standing.

After arriving in Juneau, we went on a quick tour of the town before grabbing a bite to eat and setting up camp across the lake from Mendenhall Glacier. A constant misting rain provided a fitting welcome to Alaska.
The next day we hiked up to the glacier itself while waiting for Dan Lawson and his crew to finish the necessary errands before our chartered flight to Gustavus.

A view of foggy mountains from the Cessna on the flight to Gustavus.

A view of foggy mountains from the Cessna on the flight to Gustavus.

Once in Gustavus we met the final member of our party, Sarah Laxton, who had arrived at the house before us.
The next morning the entire crew loaded into the Capelin, a small research ship, and Justin (our captain) drove us over to our first site, Beartrack, where Dr. Wiles, Kelly and Colin were dropped off for the next two nights.

The Capelin, our trusted research vessel.

The Capelin, our trusted research vessel.

The Fairweather Range, as viewed from the Capelin.

The Fairweather Range, as viewed from the Capelin.

We set up camp in a small wooded area across from Beartrack Mountain and set off on a medium length hike marred only by an arduous return trek through a bunch of windfall.

Our small camp in the woods. The area was almost an island during high tides, connected only by a tombolo to the mainland and, during low tide, another island via tombolo.

Our small camp in the woods. The area was almost an island during high tides, connected only by a tombolo to the mainland and, during low tide, another island via tombolo.

In the mud just outside of our campsite, Beartrack lives up to its name.

In the mud just outside of our campsite, Beartrack lives up to its name.

The next morning we embarked on an arduous vertical hike up Beartrack Mountain, made even more difficult by a section that had been ravaged by an avalanche, making the climb that much more difficult. Large Sitka spruce dominated the lower slopes. As we rose in elevation, some mountain hemlocks were mixed in until finally towards the top only mountain hemlock remained.

Kelly and Sarah core a mountain hemlock near our lunch site during one of the fleeting moments of sunlight.

Kelly and Sarah core a mountain hemlock near our lunch site during one of the fleeting moments of sunlight.

Colin uses the increment borer to core another mountain hemlock.

Colin uses the increment borer to core another mountain hemlock.

One added benefit of our ever increasing elevation was one of many quite beautiful views of the fjord.

One added benefit of our ever increasing elevation was one of many quite beautiful views of the fjord.

Once at our top site (next to a radio repeater station) we all split up and went off to different ridges to core some more hemlocks closer to treeline.

Dr. Wiles head off with his trusty increment borer towards one of the ridges to core some yellow cedar.

Dr. Wiles head off with his trusty increment borer towards one of the ridges to core some yellow cedar.

The next day we were picked up by the Capelin by Justin, Dan, Sarah and the rest and went by boat to upper Muir Inlet to collect samples of wood killed by glacial advances for Kelly’s I.S. These samples ranged from 8000-2000 years before present. To find these samples we hiked up to Dan’s study sites which were located in fluvial valleys where debris flows and erosion due to rain had uncovered old pieces of wood. Along the way, we saw lots of evidence of glacial presence, ranging from moraines to huge glacial erratics. It was hard to fathom that the entire hike had been covered by glaciers a mere 30 years ago.

Sarah standing in front of a huge glacial erratic (one that didn’t have that far to travel). Notice the sediment in front of it that had been pushed along during the glacier’s advance.

Sarah standing in front of a huge glacial erratic (one that didn’t have that far to travel). Notice the sediment in front of it that had been pushed along during the glacier’s advance.

The crew advances on at a time down the steep slope into the valley.

The crew advances on at a time down the steep slope into the valley.

Dr. Wiles cores a trunk along the base of the streambed.

Dr. Wiles cores a trunk along the base of the streambed.

Colin digs out a piece of wood from the wall of the valley.

Colin digs out a piece of wood from the wall of the valley.

The next day was similar. We hiked up to another stream valley to collect more samples.

Dan cuts a cross-section with his chainsaw.

Dan cuts a cross-section with his chainsaw.

On our way back down to the shore from the stream valley, the fog began to roll back and a wonderful View of Muir Inlet was revealed.

On our way back down to the shore from the stream valley, the fog began to roll back and a wonderful View of Muir Inlet was revealed.

After we relocated to another valley nearer the base of the inlet, we located some wood that we think is 8000 years old.

After we relocated to another valley nearer the base of the inlet, we located some wood that we think is 8000 years old.

After four long days in the field, we finally returned to the house for much needed showers and access to a clothes dryer. Today was spent recuperating and going over what had already been done and what still remains to do. Sadly, we also had a casualty in our ranks. Sarah flew back home to British Columbia this evening with what is probably a fractured arm.

Professor Greg Wiles in the news and a new book

July 24th, 2009

Earlier this summer the Guardian newspaper in the United Kingdom ran a photo essay about scientists working hard to sort out climate change questions. One of the people featured is Wooster professor of geology Greg Wiles in a classic photo first run in National Geographic.

From the Guardian, May 14, 2009 issue.

Wooster's own Greg Wiles looking buff as he cores a log in Alaska for dendrochronological and paleoclimate research (from the May 14, 2009, issue of the Guardian).

This photograph (and a description of Greg’s work) is now included in a new book titled Climate Change: Picturing the Science by Gavin Schmidt and Joshua Wolfe.

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