Grad News Forum

John Gartner: Using Lidar to Study Dam Removal and River Dynamics

Check out this video of recent poster session winner, John Gartner.

In the video, Gartner explains how researchers shoot lasers from a plane to map and understand the effects of dam removal on river current patterns.

Congratulations to graduate student John Gartner, in the Department of Earth Sciences, who was one of four winners of the Graduate Poster Session held recently in Alumni Hall! (Below is a summary of Gartner’s poster.)

Poster Title: Irene Landslides and Sedimentation in Vermont Rivers:  Importance of Gradients in Transport Capacity

How do rivers transport sediment from the mountains to the sea? This question has implications for every species that lives in and near rivers, including humans. Hurricane Irene, as devastating as it was to so many people, provided an unprecedented opportunity to observe how rivers cut into and also bury the local landscape with sediment.

For decades, geomorphologists have measured stream power at spot locations along rivers to determine if the capacity at a point is high enough to transport sediment. Yet the stream power of rivers is seldom constant from the headwaters downstream, and this change should affect sediment transport dynamics. Specifically, if the stream power is decreasing downstream, going from high to low power along a given segment, then the river cannot carry the sediment load delivered from upstream and must deposit material. In contrast, if stream power increases moving downstream, then the river can entrain all sediment delivered from upstream and more, possibly exporting material from the riverbanks, undercutting the adjacent hillslopes, and inducing landslides. I hypothesized that river segments with decreasing stream power should exhibit widespread floodplain deposition and few landslides, and, conversely, segments with increasing stream power should exhibit abundant landslides and minimal floodplain deposition.

To test these ideas, landslides and floodplain deposits were mapped based on field surveys and aerial photos in two Vermont watersheds after Irene. Freely available digital elevation data were used to compute stream power and, more importantly, gradients in stream power on the two rivers. The hypotheses were supported by the preponderance of floodplain deposits occurring in reaches with decreasing stream power and an abundance of landslides in reaches with increasing stream power.

This novel approach to characterizing sediment transport dynamics shows that gradients in stream power can affect both the downstream and lateral mobility of sediment. In particular, decreasing downstream sediment transport capacity favors the movement of material from the river onto the adjacent landscape. However, reaches of increasing downstream capacity have an opposite dynamic, with material moving from adjacent areas into river channels. One critical broader implication is that maps of stream power gradients can be an important tool for protection and management of human infrastructure and riparian ecosystems.

poster summary by John Gartner

Professor Cottingham, President Folt, Professor Hawley, and Dean Kull

This year’s recipients of the Graduate Faculty Mentoring Award are Professor Kathryn Cottingham and Professor Robert Hawley. Each year the Graduate Student Council (GSC) gives out two Graduate Faculty Mentoring Awards to recognize the exceptional mentoring activities of faculty advisors at Dartmouth. Award recipients are honored for their commitment to fostering the academic and professional pursuits of graduate students and receive $500 to support further mentoring activities. This year the selection committee consisted of Julia Bradley-Cook, the president of GSC, Rich Lopez, the academic chair, and Daniel Durcan, the activities coordinator. President Carol Folt announced this year’s recipients on Wednesday, April 10, at the Graduate Poster Session.

Professor Kathryn Cottingham

Professor Kathryn Cottingham is a professor in the Department of Biological Sciences in the Ecology and Evolutionary Biology (EEB) program. She joined Dartmouth faculty in 1998 and currently mentors two graduate students. Her research focuses on aquatic ecology, in particular the reasons for and results of cyanobacterial blooms in lakes and factors affecting the accumulation of mercury by fish and invertebrates in streams. Her lab has also been involved in examining dietary exposure to arsenic in pregnant women and infants.

In nominating her for this award, graduate students observed that Cottingham plays an important role as a mentor in her department as a whole. A member of the Cottingham lab observed that when she interviewed at Dartmouth “the most common response I received from other graduate students about the Cottingham Lab, was that Kathy may be the ‘official advisor’ to her own graduate students, but she ‘unofficially’ advises all the graduate students.”

Another aspect of Cottingham’s mentoring style that her graduate students appreciated was her ability to balance letting her students work independently, while also providing enough support and guidance to facilitate success in their research. One of Cottingham’s current students observed that her mentoring style “strikes a nice balance between letting me work independently to the extent that I want to” while always being available “to help troubleshoot, design experiments, and address any problems that arise.” Discussing the importance of building research skills in graduate school, several students expressed their appreciation of Cottingham’s guidance in data analysis and in improving their writing skills. One student explained, “I especially appreciate how her mentoring with me has changed through time as I have developed as a scientist, and has focused on everything from scientific writing, how to work in groups, [and] data analysis.”

Professor Robert Hawley

Professor Robert Hawley is an assistant professor of Earth Sciences. He came to Dartmouth in 2008. Hawley leads the Glaciology Research Group at Dartmouth, mentoring five graduate students and a postdoctoral researcher. The group studies the formation and make-up of polar ice sheets to explore issues related to sea level rise and climate change. Hawley developed a new technique for studying polar firn, called Borehole Optical Stratigraphy, which involves lowering a video camera into a borehole in the ice. The camera records patterns of light and dark in the walls of the borehole, which reflect differences in ice grain size and density and facilitate the studying of annual layers.

In their nominations, Professor Hawley’s students expressed an appreciation for his enthusiasm and patience. They observed that his excitement and creativity in his research were inspiring, and these were balanced with his calm and practical approach to problem solving and project management. One of Hawley’s students explained that Hawley’s “ability to bring both perspective and calm is incredible. I cannot recall a challenging ‘moment’ or issue that I could not bring to [his] attention.”

As well as developing his mentees’ skills in academic and proposal writing and teaching techniques, Hawley also encouraged students to engage in service. A member of the Glaciology Research Group wrote, “With regard to citizen-science, [Hawley’s] work with outreach (e.g., Science Pubs at Salt hill) has been an example that I hope to emulate in my own work.” In addition, Hawley encouraged his students to pursue outside learning opportunities, such as participation in the West Antarctic Ice Sheet (WAIS) Divide Ice Core Project. Finally, Hawley’s students also appreciated his willingness to prioritize their ideas and goals. A student described him as “an undeniable exemplification of a masterful mentor-extraordinaire.”

Reflecting on the process of choosing this year’s recipients, Bradley-Cook observed, “We had an impressive collection of nominees—faculty who go above and beyond to challenge, support, and motivate graduate students. Professors Cottingham and Hawley are inspiring role models with mentoring styles that genuinely support graduate students. We are grateful for the opportunity to acknowledge their extraordinary mentorship.”

The Graduate Studies Office congratulates Professors Cottingham and Hawley on their receipt of this award and thanks them for their dedication to supporting graduate students at Dartmouth.

Dartmouth’s Graduate Studies Office coordinates a Graduate Studies Externship Program, pairing current graduate students with alumni from Dartmouth’s graduate programs.  As part of the program, students spend a day shadowing their alumni host, becoming acquainted with their host’s place of employment and discussing professional goals. For his externship, Justin Richardson, a student in the Department of Earth Sciences, spent the day with Dr. George Linkletter, who has an AB and an AM in geology from Dartmouth and a PhD from the University of Washington. Dr. Linkletter is the senior vice president of the environmental consulting firm, ENVIRON. Justin writes of his externship:

The experience and insight gained from my externship with Dr. Linkletter was invaluable to my career development. Dr. Linkletter is an accomplished scientist and environmental consultant in Irvine, California, who credits his scientific success to his time at Dartmouth College. We began chatting in his office, which had a wonderful view of Orange County and a framed picture of Dartmouth Hall above his computer. As he told wonderful tales of faculty and life in Hanover, I was proud to be at Dartmouth College in the very department where he had studied.

Dr. Linkletter then offered a unique view of research outside of academia; he has worked both as a research scientist and as an environmental consultant. Dr. Linkletter described his research experience and work with consulting firms, all of which showed the applicability of skills learned in graduate school. Afterwards, Dr. Linkletter introduced me to some of ENVIRON’s past and current projects on soil and groundwater contamination. I noted that a consultant approaches a problem very differently from a research scientist. During the two conferences I attended, it was fascinating how their work moved between science, law, and business. Not only do they deal with scientific questions, but they are also held to legal timelines and financial guidelines.

Later in the afternoon, I met with two research scientists and discussed how they navigated from graduate school to a fulfilling profession. A theme emerged in these conversations: if academia does not suit you, do not feel compelled to pursue an academic career. The two scientists currently work on challenging scientific questions. However, they have greater control over where they live and the hours they work compared to when they worked in academia. A consultant’s work is more challenging and stressful than work in academia. The health and finances of residents facing contamination issues rests directly on their ability to properly conduct a study, correctly interpret the results, and act based on those results. However, Dr. Linkletter emphasized that the size and function of environmental consulting firms differ; some are small, personable firms, while others are large institutions with many employees.

As the workday came to a close, I was happy to know that working in consulting can be so captivating and rewarding.

by Justin Richardson

The Graduate Student Council (GSC) is proud to provide funding bi-annually for graduate students travelling to conferences. These funds help members of our community get the most out of their studies by helping them get to present their research and meet other experts in their field. Here are the three students who were awarded a grant for Fall term.

Maggie Baber-M.S., Earth Sciences

The American Geophysical Union (AGU) Fall Meeting is the world’s largest earth sciences meeting and provides many opportunities for academic and professional engagement. This year AGU had 22,167 attendees from 94 countries, 12,000 posters, 6000 oral presentations. While at AGU, I presented, for the first time, the results of my Masters thesis research at Dartmouth at the conference’s cryosphere poster session. I had the opportunity to ask questions and receive feedback from experienced scientists in my field, a unique opportunity as I begin editing my thesis, which is due in February. Additionally, I was able to attend several networking meetings to meet with potential employers of industry, government agencies, and national labs.

Matthew Bigl-M.S., Earth Sciences

I started my AGU experience early Monday morning as I was scheduled to present my research at 8:00.Once I got my poster up and was able to peruse the other offerings within the gigantic poster hall before returning to my poster to field questions and discussion from those who stopped by. Following my presentation I spent the next three and a half days listening to talks ranging from citizen science to climate literacy as well as many great geomorphic and climate change related topics that intertwined with my own research. My project is based around a sedimentary feature known as varves which in my case are located in the Upper Valley of Vermont and New Hampshire and formed in a glacial environment recording summer and winter in one couplet. I had the opportunity to listen to another researcher’s varve project that was based out of Ghana and recorded precipitation and therefore could be used to track drought in the local region.

Graduate students Laura Levy and Justin Stroup, from the Earth Sciences Department, were recently featured in the Valley News after taking one of it’s writers on a guided hike along the side of the Hanover Country Club. Both students study climate change and the glacial response, Laura’s research is based in Greenland, while Justin researches in Peru.

On the hike, the two discussed the geological landscape of the area, drawing attention to the changes that have occurred over time, at one point even discussing the evolution of the Dartmouth Green. The Valley News’ transcription of the conversation includes this fun fact, as explained by Laura:

“That really nice flat area [the Green] is actually glacial lake bottom. You can imagine the lake itself, when it was full, was about to the top of Baker Berry Tower, about 115 feet. We would still be under about 50 feet of water standing here (on the golf course).”

To read the full article, see the Sunday, November 4th, print of the Valley News.

photo by Tennile Sunday

About 140 miles northeast of Hanover, in the north country of New Hampshire, lies Dartmouth’s massive Second College Grant. While the Grant clearly offers fewer cultural events than Hanover, the rugged wilderness provides many unique research and recreational opportunities for Dartmouth students.

For the full article go to Dartmouth Now.

The Second College Grant was presented to Dartmouth by the State of New Hampshire in 1807 and is used for research, recreation, and sustainable logging. (photo by Eli Burakian ’00)

Melody Brown Burkins, second from left, with WISP members.

Melody Brown Burkins, Senior Director of Research & Strategic Initiatives at the University of Vermont (UVM), visited Dartmouth recently and spoke at a Women in Science luncheon. During her time as a graduate student at Dartmouth, Melody served as President of the Graduate Student Council (1998-1999), and also won the Hannah Croasdale Award for excellent in research and teaching. She has recently been appointed Dartmouth’s Graduate Alumni Rep to the Alumni Council.

Asked why she chose Dartmouth for her graduate studies, Melody explained that Dartmouth was one of two top choices and the deciding factor was that Dartmouth’s Earth Sciences program was more flexible, allowing her to take a variety of classes and explore her options, whereas the other program she was considering was very structured and specific. It was her experience at Dartmouth that first sparked her interest in policy. As a graduate student, she participated in many long-term ecologic programs that were funded by the NSF (National Science Foundation). Despite all of her exciting, albeit grueling, projects—working under the scorching sun in the Jornada Desert in New Mexico (“I think I only passed out once,” she jokes, “it was hot”), and then in the vastly different, freezing climates of the Antarctic—Melody found her interests expanding outside of research.

“I was fascinated by the science, but I really wanted to learn about how these projects were funded, and who was paying for it,” said Melody. She was thrilled when she was selected for the National Congressional Science and Technology Fellowship–a fellowship in which, according to Melody, “clueless scientists were thrown into congress.”

The position called for concise, non-scientific writing and communication and, through some trial and error, she realized that the strategies that would have been very appropriate in academia were not as effective in her new position—she needed to change her approach, and quickly did. “I was learning from people who were younger than me and had so much more experience in this world than I did,” she revealed, adding, “I learned to be very humble and realize that even with my expertise, there was still a lot to learn.”

She was soon offered the role of Special Legislative Assistant, to Senator Patrick Leahy, and, not long after, The University of Vermont, having heard what Melody had done for them from DC (in terms of science and policy) offered her a position there. “They wanted me to take programs that had a lot of investment but no funding and secure funding for them with support from the delegation. It was a perfect fit!” she explained.

On the flip side of her developing career path, Melody and her partner were (and still are) raising a family together, and the demands of her various positions required them to make some decisions regarding childcare and work. To make the balancing act less tedious, her husband (whom she met at Dartmouth) decided it would be best for the family if he became a stay-at-home dad, and Melody continued to pursue her career goals. This dynamic has worked beautifully for them, and now he is exploring a new career as a singer/songwriter—a venture he originally began as a graduate student, at Dartmouth.

Aside from having a supportive family, and being adventurous and open to change, Melody encourages students interested in non-academic work to network, and to realize that their application process may need to be self-guided since many advisers will not have connections outside of science. She also urges individuals to remember that their graduate degree does not mean that they will be experts in any field they choose to venture into; hard work, and the willingness to learn and adapt are key. For those who see themselves in managerial positions, Melody stressed that everyone benefits when you give your team trust and support, “what people need is to be heard and then championed. Invest in your people first.”

Asked about her future plans, Melody happily mused, ” I’ve thought about taking some time to write a book or a course, perhaps on how to get scientists talking together, and how to get their points across to non-experts, and therefore how to obtain funding–basically the stuff I most struggled with when I first started. But really, I’m open to whatever paths may present themselves!”

by Tennile Sunday

In a recent editorial, the journal Nature stated that, when it comes to climate change research,“Scientists must acknowledge that they are in a street fight.” Is this true? Has public discourse about climate change become so heated that even a respected scientific journal calls it “a street fight”? As graduate students in the Ecology and Evolutionary Biology program here at Dartmouth, we have been fascinated by the disregard for science in shaping public policy in our federal government. We have often asked ourselves why this is the case, and quickly realized the complexities of this question. A few months ago we decided to formally address this question by organizing a multi-day series centered on the theme of how politics and rhetoric subvert science in shaping public policy, with climate change being the major case study.

The Communication Street Fight: Scientists, the Media, and Politicians in the Climate Change Debate

-Talk: Shawn Otto, April 30, 4 pm, Oopik Auditorium, Life Sciences Center
Free and open to the public

Otto is an Oscar-nominated screenwriter and filmmaker who advocates for “smarter politics” in our national discourse on scientific topics. Along with other advocates, he helped organize an online discussion on scientific questions between candidates Obama and McCain in the 2008 election. He has also written a book Fool Me Twice: Fighting the Assault on Science in America about how the American discourse on science has changed, and the impact that has on policymaking.

-Talk: Dr. Peter Frumhoff, May 10, 4 pm, Oopik Auditorium, Life Sciences Center
Free and open to the public

Dr. Frumhoff is the Director of Science and Policy, Union of Concerned Scientists (UCS). This spring, the UCS will launch a national project on “Science and Democracy,” placing them in an ideal position to address this topic. Dr. Frumhoff is a global change ecologist, who has served diverse roles in the scientific and policy arenas. He was also a lead author in the most recent Intergovernmental Panel on Climate Change (IPCC) assessment.

-Film Screening: “Bidder 70”, May 14, time and location tbd
Free and open to the public

This event addresses the role of activism in the public discourse on climate change. Acclaimed author Terry Tempest Williams will lead a discussion following the film. On December 19, 2008, Tim DeChristopher, as Bidder #70, derailed a federal oil and gas lease auction, by bidding on and winning 22,000 acres of land with no intention to pay or drill, effectively safeguarding thousands of acres of federal land. DeChristopher’s disruption of the auction enabled the Obama Administration and Interior Secretary Salazar to invalidate the auction, citing inadequate analysis of the environmental effects on surrounding areas and failure to assess contributions to global climate change. For his disruption of the auction, DeChristopher was indicted and convicted on two federal charges.

Co-sponsored by Environmental Studies, the Department of Biological Sciences, and the Graduate Student Council

Contacts: Carissa Aoki — Carissa.F.Aoki.GR@dartmouth.edu, Jeff Lombardo –Jeffrey.A.Lombardo.GR@dartmouth.edu, Chelsea Vario -Chelsea.L.Vario.GR@dartmouth.edu

Born in San Diego, CA, Justin Richardson is a first-year graduate student in Dartmouth’s Earth Sciences department. Describing himself as “the soil man,” Justin’s research examines how toxic metals are transported in upland forest soils. As an undergraduate at University of California, Riverside, Justin worked as a Soil Science Adviser at his campus’s organic community garden, and for the nine months that he has been a member of the Dartmouth graduate community, he has used his knowledge of soils to assist instructors with the educational courses held at the Dartmouth Organic Farm. At the community farm in Southern California and Dartmouth’s Organic Farm, Justin applied his knowledge of sustainable farming methods to control the nutrient levels in each farm’s soil.

Justin’s graduate research builds upon his deep-seated interest in soil science and environmental sustainability. As a graduate student, Justin is researching the ability of soils from different regions of the northeastern United States to retain mercury—a toxic metal released into the atmosphere during coal combustion—and lead—a heavy metal released by automobiles before leaded gasoline was phased out in the 1970s. The organic matter and mineral content present within soils creates a buffer that slows the leeching of these metals into the region’s subterranean aquifers; once in the aquifers, these metals gradually move up the food chain. Though research suggests the lead that enters our waterways is not absorbed by humans, it has been proven that humans absorb mercury through the consumption of predatory fish that feed in contaminated waters.

“Though mercury isn’t good for you, I still enjoy eating locally caught fish,” says Justin. “You just have to watch which species you consume.”

Currently, Justin is examining the heavy-metal retention properties of both the organic matter and mineral content of various soils, which differ greatly from region to region. Comprised primarily of decomposing plant matter, the organic structures of a forest’s floor determines how well it is able to retain metals: in evergreen forests, the carbon structures of the fallen pine needles are relatively stable and are able to hold metals for longer than the carbon structures of the downed leaves in deciduous forests, which fall from the hardwoods of New England each autumn.

The mineral content of a soil is the final buffer that slows the leaching of lead and mercury into the waterways of the Northeast. After passing through the forest floor, different minerals hold toxic metals before they move into the subsoil. Recent studies suggest that the greater the clay content of a soil, the better it is at retaining toxic metals. Currently, Justin is examining the ability of New England’s soils, which vary in their clay content, to retain lead and mercury.

“Although there aren’t that many coal-burning plants in New England, there is a major mercury problem in this area,” says Justin. “The mercury released by coal plants in the midwestern United States travels through the atmosphere, and ends up in our soils.”

This summer, Justin helped teach laboratory sections held at the Dartmouth Organic Farm to the school’s ecological agriculture class. Located three miles up river from Dartmouth’s campus, the Organic farm is an educational facility that teaches students methods for sustainable food production. Unlike the organic community garden Justin worked at as an undergraduate—which is divided into small land plots that students and community members manage independently—Dartmouth’s Organic Farm is not partitioned, which allows for greater control over both the nutrient levels in the soil and the prevention of parasitical crop damage through organic farming methods. Justin explains that this structural feature of Dartmouth’s Organic Farm makes the facility well suited for teaching.

“One thing that’s unique about Dartmouth’s Organic Farm is that the farm is built upon the official ‘Dartmouth series soil,’” explains Justin. “The official soil taxonomic name for many of the low lying areas along the Connecticut River Valley is named after our school, and I think that’s something that Dartmouth students should know.”

To become involved in Dartmouth’s farming community, drop by the organic farm anytime to learn about its seasonal happenings. In the summer, students run a farmstand outside of the Collis Center where they sell fresh produce to the community. If you’re new to horticulture, Dartmouth’s Organic Farm holds “work days” designed to teach students the basics of sustainable farming; the farm also hosts pot-luck dinners on a regular basis for everyone who helps out at the farm.

If you’d like to learn more about Dartmouth’s Organic Farm, or are interested in soil science, it’s easy to spot Justin in Hanover: his NH license plate is “SOILSCI.”

by Wesley Whitaker