National Science Foundation
Antarctic Glaciology
Program Grant Proposal
Submitter: Anna Sparer
Institution: Humboldt State University
Due Date: January 25th, 2016
Anna Sparer
Quaternary Stratigraphy
NSF Mock Proposal
Core Sample Drilling of the Interior West Antarctic Ice Sheet to
Determine Dynamics of Antarctic Glaciers during the Last
Glacial Maximum and the Mid-Pliocene
Summary
The West Antarctic Ice Sheet (WAIS) has been under investigation for decades, however
it is only in the last 20 years that research on the WAIS has truly taken off, due to the ecological
and economical impacts of the WAIS collapsing and melting into the ocean. These impacts,
primarily significant sea level rise and marine biological destruction, have been media
sensationalized and triggered a boom in scientists researching the dynamics of the WAIS during
paleo-climates, especially during the Last Glacial Maximum (LGM), 21ka, and mid-Pliocene, 3-4
ma, which was substantially warmer than the present day climate. There have been numerous
models and theories that have risen that favor the possibility that the WAIS could significantly
collapse within decades, and there are theories that refute the previous, stating that the
possibility for imminent glacial collapse is extremely unlikely, and that there is plenty of time for
reversal. I have examined models presented by a number of researchers and will provide a
comprehensive discussion of these models, and the future of the various research agendas
involved.
Many of these models are simulations using calculations based on observations and
data collected from the WAIS. This data incorporates a large amount of data taken to
understand the dynamics of the East Antarctica Ice Sheet, which is believed to have been
instrumental in the formation of the WAIS. Our data includes empirical constraint, ice core
samples, remote sensing data, topographic and satellite imaging along with our models
(Vaughan). These models examine glacial dynamics with emphases on correlation between
increased CO2 levels, climate forcing, isostatic ice loading with erosion of the underlying
bedrock, ice streams, surface mass balance, deep water formation, and sea ice formation with
albedo feedback (DeConto). Research agendas in these fields vary substantially, primarily
diverging between the possibilities of the collapse of the WAIS being something that is innate
versus something that is anthropogenically instigated (Thomas, 2013). I intend to continue
research on bedrock sediments after sediments retrieved from James Ross Island, the largest
area on the West Antarctica Peninsula with no ice revealed that records in the sediment
showed evidence of a smaller WAIS during recent interglacial periods. A joint effort by the US
National Science Foundation and British Antarctic Survey in 2004/2005 collected over 70,000
km of geophysical data from the air, which allows for the mapping of the topography beneath
the ice sheet across the Amundsen Sea (Glasser). It is ultimately imperative that inner regions
of the WAIS get drilled into the underlying bedrock where an accurate record of glacial
dynamics exists. It would be invaluable to have information on the size of the WAIS during
warmer inter-glacial periods to predict the nature of the WAIS’s melting and collapse during
those periods. This would assist in our prediction of climate change and sea level rise, and
compare the sediments to our present CO2 levels and temperatures. In addition to the drill
cores of the interior WAIS, I intend to use cosmogenic isotope age dating to determine the ages
of cores of sediment retrieved that underlay paleo-ice streams which will allow researchers to
correlate the ages of the core sample sediments to recent glacial events. I hope to persuade
the NSF to award my grant to pursue this research topic, because I believe it will provide an
incredible amount of data that will improve our understanding of climate change and the
overall behavior of the WAIS and other glacial units.
Preceding Work/Research
The previous work that inspired my research was conducted over the coarse of 20082013 and included a number of research agendas and topics. The East Antarctica Ice Sheet
(EAIS) is studied widely to understand typical glacier dynamics and the stability of the ice sheet
during paleo-climates. The model used were a glacial flowline model that simulates the Ferrar
Glacier under current conditions found today and under colder conditions, to simulate the Last
Glacial Maximum (LGM) at 21ka, and under warmer conditions, simulating the mid-Pliocene
temperature peak (3-4 Ma) (Golledge et al). It was determined that at the LGM, the Ferrar
Glacier had basal pressure melting of the ice at about >1 km, very little deformation, and the
deformation velocities were slow, with minimal sliding, therefore having minimal bedrock
erosion and till generation. At simulated present day conditions, basal pressure melting was
again at >1 km. The rate of deformation was slightly higher than the LGM scenario, although
the rate of basal sliding was still low, and consequently, so was the amount of bedrock erosion
and basal till formation. During the mid-Pliocene warm scenario, a steeper glacier profile is
evident, as well as a fast-flowing glacier (Golledge et al). The increase in deformation and basal
sliding is due to the increased precipitation and temperature in the atmosphere and the steep
glacier faces. This produces more basal till and more bedrock erosion, and may have produced
isostatic adjustments due to the deglaciated crust rebounding coupled with the increased crust
depression in areas with thicker ice. This study provided insight into the dynamic of outlet
glaciers during various climatic scenarios. (Golledge et al)
Antarctic sea ice has critical effects on the climate, including the energy transfer
between the ocean and the atmosphere, moisture, and radiation balance (DeConto et al).
Analyzing sea ice in the context of feedbacks in the Cenozoic, during which the Antarctic ice
sheets formed. Antarctic sea ice appeared as a response to the continental glacier and were not
a huge influence on glacial periods during the Paleogene and Neogene. In this model,
greenhouse gases decreased during the Cenozoic and continental ice sheets formed initially,
and once they were established, the amount of seasonal sea ice that formed around the
continent was determined largely by orbital forcing and the geometry of the ice sheet, which
had control over the local temperature and low-lying winds (DeConto et al). The East Antarctic
Ice Sheet had influence on sea ice in the region and also on surface temperatures in the nearby
ocean and wind, which had a large influence on ocean circulation, the carbon cycle in the
ocean, and also the formation and evolution of the West Antarctica Ice Sheet (DeConto et al).
This implies that the West Antarctica Ice Sheet is an indicator of conditions in the interior of the
continental ice. Due to sea ice’s sensitivity to continental ice sheets, this study utilized marine
diatoms as indicators of conditions around the interior continental glaciers to reconstruct
scenarios and found that they provide insight into the stability of the Antarctic Ice Sheets long
term. Research determined that the periods of time that were the coldest also had the most
marine diatoms. During the Pliocene, the samples had absent or minimal diatoms which is
evident of relatively low glacial volume (DeConto et al).
Ice core records show that warming began roughly 600 years ago over the WAIS, and
summer snow-melt accelerated during the 20th century. The warming noted has been
connected with differences in westerly winds that surround Antarctica, which have warmed it,
resulting in the recession of the Western and Peninsula glaciers. The glaciers in the north, near
the peninsula are shrinking because the collapse of the Prince Gustav Ice Shelf in 1995 resulted
in mospheric warming (Glasser et al)
,t Collecting and dating erratic boulders located on James Ross Island using cosmogenic
isotope exposure age dating to determine the progression and the terrestrial dynamic of ice
sheets during the LGM. A paleo-ice stream formed and flowed northwards to the edge of the
continental shelf as a result of an ice dome that existed throughout the LGM and areas of
accumulation. Cores and large scale bathymetry of marine sediment from this region and this
paleo-ice stream would reveal any subglacial tills and lineations resulting from the end of the
LGM (Glasser et al). Using cosmogenic isotope exposure age dating of boulders transported
onto James Ross Island by the ice sheet we would be able to recreate the the ice sheet’s
recession following the LGM. James Ross Island because is unique geologically (Glasser et al). It
is formed from Cretaceous sedimentary rocks and unconsolidated sediments, underneath
Neogene basalt of the James Ross Island Group, which are flood basalts with glacigenic strata
made up of diamictites at the bottom and enmeshed with it (Glasser et al). These erratic
boulders on James Ross Island are metamorphic and granitic in origin. Cosmogenic isotope
dating of glacially transported erratic boulders is a routine and widely accepted method for
dating glacial features like moraines (Glasser et al). Also, bedrock beneath the glaciers may not
be heavily eroded because the glaciers have a tendency to freeze to their bedrock, which would
make them ideal candidates for cosmogenic isotope age dating (Glasser et al).
Project Goals
Given the information that can be gained from the bedrock beneath the WAIS about
glacier dynamics in paleo-climates and the implications for the future of the ice sheet, whether
it is likely to collapse within the near future, releasing a cataclysmic amount of fresh water into
the ocean. I intend on pursuing research directed at ice-streams and their underlying bedrock,
as well as on James Ross Island, which is one of the largest ice-free regions in the Antarctic
Peninsula. Drill cores from James Ross Island will provide an immense amount of insight into
glacier dynamics, since it’s one of the only ice-free landforms located in that region, and will
provide conditions that forced the formation of the WAIS, its stability in paleo-climates and in
the future (Glasser et al). This will reveal the direness of climate change, and how serious the
CO2 of anthropogenic origin is. It will provide information on what the future is for the ice
sheets, both in decades and centuries away, and how the change in the ice sheets will affect
humans, in context of sea level rise, atmospheric change, deep water formation and the
thermohaline ocean circulation and what all that means for us, ecologically and economically.
Ideally, based on the models that have been exhibited in the past, the most efficient pathway
to understanding glacial dynamics is through drilling into the interior of the continental ice
sheet and using cosmogenic isotope age dating to date the samples and correlate them to
significant glacial events. Drill cores of the sediment taken from the margins of the ice sheet
reveal a lot of information about the tendencies, the development and the disintegration of ice
sheets over time. Ice cores show that temperatures during interglacial periods in the past were
higher than today (Glasser et al). If WAIS experienced rapid deglaciation as a result of warmer
temperatures, then the likelihood of collapse due to anthropogenic climate forcing is much
higher. However, if WAIS seems to have survived interglacial periods and remained in tact, then
the likelihood of collapse is much less, and that the thinning of the glacier is innate and has
more to do with reaching a new state of equilibrium. The record of this dynamic is in the
bedrock sediments beneath the ice sheets (Glasser et al). The sediments retrieved from the
margins of the WAIS by drilling indicate that a much smaller ice sheet existed during recent
interglacial periods, but we really need to know if the interior of the ice sheet confirms what
the cores from the margin suggest. Given the drilling technology and advances since the last
exploration in 2004 which resulted in these margin cores, I intend to drill into the interior of the
middle of the WAIS and use cosmogenic isotope age dating on the sediments to provide
concrete data that either supports or refutes the data from the margin cores (Glasser et al).
The increased amount of area of the Antarctica Ice Sheets covered using airborne
geophysical data and subsequently mapping it, will increase the understanding of the ice sheet
and if it really is prone to collapse, and if so, when it is likely to do so, and how much of it would
be melted into the ocean. It would also provide information on if there is any chance of
reversing the damage or any measures that can be taken to cease the progression of
deglaciation in West Antarctica (Vaughan et al). It would be of equal importance to address the
curious thickening of the ice sheet in East Antarctica, which is potentially due to increased
runoff, precipitation and increased ice flow near the Antarctic Peninsula (Glasser et al). I intend
to determine how each of these factors are and will affect sea level in the coming decades. The
deep water that surrounds Antarctica, the Circumpolar Deep Water (CDW) is beyond the
continental shelf and does not come in contact with the ice sheets, but it does flood the
continental shelf and comes into contact with the floating ice shelves near the Amundsen Sea,
which is responsible for the increasing basal melting that is found in that region (Glasser et al).
Increased ice shelf melting is the inherent cause of the changes surrounding the WAIS. The
WAIS is essentially thinning because of these changes in the ice shelf, and is a result of glacial
acceleration over in the EAIS (Glasser et al). The Amundsen Sea section could begin to largely
influence sea level rise within a few decades. Much information regarding the glacial dynamic
can be gained by increasing the understanding of the bedrock beneath the paleo-ice streams
that surround the WAIS. Focusing on the sediment there would provide an invaluable insight
into the glacial dynamic and behavior in addition to the cores that would be drilled in the
middle of the WAIS (Vaughan). In addition to drilling in the WAIS’s center and beneath paleo-ice
streams. Paleo-ice streams are “corridors of fast flowing ice within an ice sheet and are typically
hundreds of kilometers long and tens of kilometers wide” (Livingstone et al). Due to their
speed, paleo-ice streams are capable of draining a substantial amount of ice and therefore they
have a critical influence on the stability, geometry and mass balance of ice sheets. paleo-ice
streams, which are influenced by ocean and atmospheric temperature, changes in sea level,
tides, bathymetry beneath the glacier, the ice-stream’s thermodynamics, and the size of the
drainage basin that it outlets into (Glasser et al), exhibit variations between them depending on
the listed above conditions, under which they formed. Depending on which variations they
feature, a picture is depicted of what glacial climate was like. Given that most of the paleo-ice
streams that are present in Western Antarctica were formed since the LGM, the information
available in them has potential to expose small glacial periods between the LGM and now. I
intend to sample drill cores of various paleo-ice streams and use cosmogenic isotope dating to
confirm this. Paleo-ice streams have been identified a number of times from the LGM and
provide information on the ice-stream location and history, which is useful for many ice sheet
models. They tend to outlet into ice shelves or open water, the latter being responsible for the
most rapid deconstruction of ice sheets due to ice-streams that release into open water being
the fastest flowing (Livingstone et al). Ice-streams in Antarctica are marine and extended across
the continental shelf. Most of the paleo-ice streams in Antarctica exist in Western Antarctica
and the Antarctic Peninsula, which has been the location of most of these studies (Livingstone
et al). The data collected from these ice-streams implies that the WAIS extended all the way to
the continental shelf during the LGM. The bedrock beneath the ice-streams is what determines
the location of the stream and the flow velocity. Analysis of the core from a paleo-ice stream
and the surrounding parts of it is useful to determine the topography, erosion patterns,
substrate composition, its transport and deposition (Livingstone et al).
I intend on answering questions that science has had for decades about our changing
climate, and providing insight into what the WAIS will look like in the near future by analyzing
its dynamics in the past. I will confirm the findings of previous studies by drilling the interior of
the WAIS and I will address the implications of my findings and use them to further glacial
science and climate change research and education for the public. If the WAIS is on the verge of
collapse, I will determine a timeline of events using new and accurate cosmogenic isotope age
dating, that dictates when events have taken place and can help interpret when the likelihood
of collapse may be and the immediate and long term repercussions of such an event, and what
they mean for sea level rise, for atmospheric changes, deep water formation and the
thermohaline circulation system that are in jeopardy because of the rapid melting. I hope to
enlighten the public on the situation that the WAIS is in and what it means for people
individually. I would participate in research and projects that would address innovative
solutions to the serious issues that we face if my findings are in favor of imminent WAIS
collapse. I hope that my findings would be incorporated into schools and industries, so that the
public can learn and change their actions that have caused the deterioration of the WAIS. If my
findings suggest that imminent collapse is not a factor, I would like to explore possible ways to
halt the progression of deglaciation the WAIS is experiencing and keep it from being damaged
further. I plan on publishing my findings in a short amount of time so that environmental
agencies and corporations can have access to my findings and the progression of climate
change and glacial research can advance and build on itself. I would like to inspire the younger
generations to take an interest in this material and learn the vital nature of protecting ourselves
and our planet. If my findings support WAIS surviving interglacial periods, and I determine that
anthropogenic greenhouse gas forcing is not the cause of deglaciation on the WAIS, and that it
is simply part of a innate cycle that causes the Antarctic climate to reach a new equilibrium, I
hope to gather enough information and data to determine what that information and data
means for sea level, atmosphere, thermohaline circulation and deep water formation and the
ecological and economical affects that may arise from it. I believe that obtaining the data
mentioned in this proposal will lead to a great and deep understanding of glacial dynamics in
Antarctica which would provide researchers and analysts with invaluable information that will
assist in increasing the strength or even change the face of the scientific fields that benefit from
or surround glacier science and climate change research. With an award from the NSF I believe
it would be possible to accomplish the above goals and provide an enormous amount of
extremely valuable information about the truth behind climate change, which, given the
amount of muddling on the part of the media, to have the facts readily accessible to people of
all communities and ages and be able to provide them with the direction we are headed in
regards to sea level, ocean circulation, and atmospheric climate and how it will affect different
places. Having the facts obtained by this research available to the public, the public would be
better informed and less confused in regards to the warming planet.
References Cited
DeConto, Robert, David Pollard, and David Harwood. "Sea Ice Feedback and Cenozoic Evolution
of Antarctic Climate and Ice Sheets." Paleoceanography, 22.3 (2007): PA3214-PA32np.
Glasser, NF, BJ Davies, JL Carrivick, A Rodes, MJ Hambrey, JL Smellie, and E Domack. "Ice-stream
Initiation, Duration and Thinning on James Ross Island, Northern Antarctic Peninsula."
Quaternary Science Reviews, 86 (2014): 78-88.
Golledge, N, and R Levy. "Geometry and Dynamics of an East Antarctic Ice Sheet Outlet Glacier,
Under Past and Present Climates." Journal of Geophysical Research. Earth Surface, 116.3 (2011):
.
Livingstone, Stephen J, Colm Ó Cofaigh, Chris R Stokes, Claus-Dieter Hillenbrand, Andreas Vieli,
and Stewart S.R Jamieson. "Antarctic Palaeo-ice Streams." Earth-Science Reviews, 111.1-2
(2012): 90-128.
Thomas, William. "Research Agendas in Climate Studies: The Case of West Antarctic Ice Sheet
Research." Climatic Change, 122.1 (2014): 299-311.
Vaughan, David. "West Antarctic Ice Sheet Collapse – the Fall and Rise of a Paradigm." Climatic
Change, 91.1 (2008): 65-79.
Vizcaíno, M, U Mikolajewicz, J Jungclaus, and G Schurgers. "Climate Modification by Future Ice
Sheet Changes and Consequences for Ice Sheet Mass Balance." Climate Dynamics, 34.2 (2010):
301-324.