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2014 Research Projects
2014 Graduate Research Fellowships
PROJECT: Investigation of Near-Earth or Ionospheric Modification of Pulsating Auroras
PI: M. Jason Ahrns, Faculty mentor Donald Hampton, UAF
Pulsating Aurora is a common type of auroral form typically seen in the hours after midnight
where patchy, extended regions of auroral emissions rise and fall in intensity on the scale of seconds
(Fig. 1). Though it's one of the more common types of auroral activity, it has inspired a comparatively
small amount of research when compared to the brighter and more dynamic discrete arcs of the earlier
auroral substorm stages. While the discrete aurora certainly has a higher rate of energy deposition into
the ionosphere, it is also fairly short lived and confined in spatial extent. The diffuse and pulsating
aurora, on the other hand, generally covers a much larger spatial and temporal extent, and therefore
actually represents as much or more total energy input into the ionosphere than the discrete
aurora, possibly from 50% to as much as 80% of the total auroral energy input (Meredith 2009).
Though a theoretical model based on wave-particle interactions exists for the generation of pulsating
auroras, observations, particularly those enabled by more recent instrumentation, cast doubt on the
universality of the model. This suggests one or more poorly understood mechanism/s, more
Earthward than the standard model, that produces or modifies the transport of particles and
energy from the magnetosphere into the ionosphere, and on into the neutral atmosphere.
PROJECT: The role of biota in snowmelt on glaciers in Alaska
PI: Gerard Ganey, Faculty mentor Roman Dial, APU
Life in frigid environments on Earth is one of the best models of astrobiology for other worlds like Europa, Jupiter’s moon, where NASA announced that water vapor plumes had been detected with the Hubble Space Telescope (Spencer, 2014). On Earth, four kingdoms of life have been identified as cryophilic (Napolitano and Shain, 2004) most visible of which is red snow algae (Chlorophyta). The study of red snow algae is thus relevant to the fields of extremophile biota. In addition, red snow algae have been identified to play a role in carbon cycling, (Takeuchi et al. 2006), ice melt (Kohshima et al. 1993) astrobiology (Hodson et al. 2008). Most previous research on glaciers has been physical and earth science. This proposed project focuses on the role of Chlamydomonas nivalis, the most common red snow algae (Remias et al. 2005). Chlamydomonas algae are found on snowfields worldwide (Hoham and Duval, 2001). These widely distributed protists, along with other impurities of local and allochthonous origin have been shown to increase absorbance of electromagnetic radiation (EMR) and so reduce albedo (Thomas and Duval 1995; Painter et al. 2001;Takeuchi et al. 2013). As algae reduce albedo, they likely increase snowmelt. It is well known that impurities in snow increase snowmelt (Conway et al. 1996, Hock et al. 2005). However, three features of red snow algae make them qualitatively different than other impurities: (1) as living organisms they resurface and reproduce even after being buried by new snow, (2) they prefer wet snow, (3) their red color reflects visible EMR that is preferentially absorbed by snow crystals (Warren and Brandt, 2008). This project is an application of STEM through manipulative experiments and data analysis and will further understanding of reduction and fluctuations of the glacial cryosphere and ice-dwelling biotic communities. Besides focusing on the ecology of organisms pertinent to astrobiology and NASA’s Exobiology and Evolutionary Biology (Exo/Evo) Program, the project includes remote sensing and its application to the effects of climate change.
PROJECT: Sea ice influence on benthic community variability in the Alaskan Arctic shelves
PI: Alexandra Ravelo, Faculty mentor Brenda Konar, UAF
Along the Arctic continental shelves epibenthic organisms can be found in high abundance and
biomass. Several members of the benthic community constitute key elements of the Arctic food
web; as prey of marine mammals, birds and fish (Bluhm & Gradinger 2008). Specifically diving
sea ducks, bearded seals, grey whales and walruses feed on benthic organisms. Among the
important epibenthic species encountered on the Alaskan Arctic shelves are brittle stars,
amphipods, snow crab, hermit crab and shrimp (Bluhm et al. 2009, Ravelo & Konar In Review,
Ravelo et al. submitted). Epibenthic communities in the Arctic are dominated by certain taxa
over large spatial scales until key environmental drivers interrupt their distribution (Piepenburg
2005, Ravelo et al. submitted). In the Chukchi Sea, echinoderms occur in dense assemblages
(several hundred individuals per meter square) and high biomass, up to 30% higher than the
highest values reported for echinoderms in the Barents Sea (Ambrose et al. 2001). On the
western Alaskan Beaufort shelf epibenthic invertebrates made up to 94% of the total benthic
standing stock (Rand & Logerwell 2010).
PROJECT: Development of a New Detection Method Using Laser-Induced Fluorescence Capillary Electrophoresis for Future Studies Investigating Adenosine’s Role in Bone Metabolism
PI: Terilyn Lawson Stephen, Faculty mentor Tom Green, UAF
The primary objective of the proposed research is to develop a highly sensitive and robust detection method for adenosine, an important biological compound involved in several biochemical pathways such as bone metabolism and neuromodulation. The development of a new detection method would improve the current physiological understanding of adenosine and potentially advance current studies designed to reduce the negative impacts of space travel such a accelerated bone density and muscle loss.
PROJECT: The Neotectonic framework of the Talkeetna Mountains, southcentral Alaska
PI: Demi Mixon, Faculty mentor Wesley Wallace, UAF
The Talkeetna Mountains are an anomalous topographic high in south central Alaska located in
the center of a long-lived forearc basin. Observing such a topographic high between a forearc
basin raises some speculation about its origin. Why are the Talkeetna Mountains a topographic
high when they are along the trend of this basin, and do active tectonic structures contribute to its
uplift? A relevant tectonic feature that might have influenced the creation of this topographic
high is the northward flat-slab subducting Yakutat microplate beneath the North American
margin. The boundary of flat-slab subduction of the buoyant Yakutat microplate is taking place
beneath the mountains (Finzel, 2011). I hypothesize that the Talkeetna Mountains have been
uplifted primarily as a result of buoyancy and/or flexure associated with flat-slab subduction, but
local relief may reflect fold and fault structures resulting from westward rotation of the southern
Alaska block south of the Denali fault.
PROJECT: Recent Changes in Shrub Distribution and Abundance in the Chugach Mountains, Alaska
PI: Christina Rinas, Faculty mentor Carl Tobin, APU
Recent studies establish that shrub expansion is occurring in Arctic and alpine areas throughout the circumpolar north (Myers-Smith et al. 2011), and that this expansion is congruent with warming temperatures (Tape et al. 2006; Sturm et al. 2005). While climate change is likely the driver of overall shrub expansion, local influences may cause heterogeneous shrub changes across the landscape, making it difficult to predict how shrubs will response to future climate change (Myers-Smith et al 2011).