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Antarctic
Research
Centre
annual review 2015
2015 IMPACTS BY NUMBERS
3
25
Rutherford Discovery Fellows now at 460
radio, TV and newspaper
the ARC with Nick Golledge joining Nancy
interviews given by ARC staff on Antarctic
Bertler and Rob McKay.
and climate related issues.
telecasts on the American
Public Television network showed the
climate change film Thin Ice to an estimated
audience of 120 million. 68
13
percent reduction of New
Marsden Fund grants awarded
Zealand’s Southern Alps glaciers by the year
to ARC staff since 2001, of these seven
2100 according to monitoring and modelling
were Marsden Fast-Starts. Co-principal
by the ARC glaciology team.
investigators Nancy Bertler and Rob McKay
1
won a new grant in the 2015 round.
st evidence of the occurrence of
23
an Antarctic marine ice sheet instability
mechanism, thought to drive abrupt global
sea-level rise, was reported by Richard Jones,
Nature, Science and
Andrew Mackintosh and Nick Golledge in
Proceedings of the National Academy of
Nature Communications.
Sciences papers have been authored by ARC
staff with two led by ARC staff in 2015.
40
2
cm of additional sea-level rise,
authors contributed to the current above the predicted 98 cm reported by the
IPCC 5th Assessment Report from the ARC, IPCC for the year 2100, may come from
Tim Naish and Dan Zwartz. Antarctic ice melting according to Nick
9
Golledge in Nature.
theses submitted - seven PhD and
two MSc students completed in 2015.
285
35
submarine cable
systems under-pinning over 98% of global
presentations and panel communications and Internet are monitored
discussions given to the public, stakeholders for climate hazard-related damage by ARC’s
and decision makers by ARC staff. Lionel Carter, advisor to the International
Cable Protection Committee.
antarctic research centre annual review 2015 1
Contents
DIRECTOR’S SUMMARY
Our Mission and Research Approach 4
Major Research Outcomes 6
Other Research Outcomes 10
Science Drilling Office 16
In this years annual review we have urgency heightened by the Paris climate
Teaching and Supervision 18
introduced a new format that emphasizes, negotiations (COP 21) held at the end
Significant Events 20
up front, the major outcome benefits of the year. Thirty-five presentations
Financial Summary 28
Outreach 30 from our 2015 research activities. and panel discussions were made to the
Publications and Invited Presentations 32 Firstly, in “Impacts By Numbers” public, policy-makers and stakeholders
Conferences 34 section we highlight research impacts including local authorities, government
List of Collaborators 35 that distinguish themselves on the agencies, non-governmental think tanks,
Directory 36 basis of excellence and relevance. We political parties and politicians, school
then profile in more detail four new and community groups. Staff also made
Antarctic Research Centre-led, policy- 25 media appearances on radio, TV,
relevant discoveries, that will help reduce and in print, discussing the implications
uncertainties around glacier and ice sheet of proposed climate mitigation for
contribution to future sea-level rise. We Antarctica and sea-level rise on the back
also provide a “rubber hits road” example drop of COP 21.
of how our knowledge of climate and
hazard driven deep ocean processes are Although it’s always so hard, I like to
being applied to manage and protect pick out a few of the most significant
submarine telecommunications cables. achievements. Nick Golledge is the
Professor Tim Naish
third ARC researcher (following Nancy Director, Antarctic Research Centre
In February we moved back into the Bertler and Rob McKay) to be awarded
5th floor of the Cotton Building on a prestigious and highly competitive Survey. A new permafrost drill capable of
Kelburn Campus, and were reunited Rutherford Discovery Fellowship. Nick’s recovering up to 30 m long cores was also
with our friends and colleagues in the Nature paper, “The multi-millennial developed and tested in collaboration
School of Geography, Environment Antarctic commitment to future sea-level with long time partners, Webster Drilling.
and Earth Sciences (SGEES). The new rise” provides new estimates for Antarctic This will be used in the Friis Hills, Dry
digs are much improved and walls are ice sheet contribution to future sea-level Valleys, in 2016 to support an MBIE
handsomely adorned by some great rise, and shows the only climate scenario funded collaborative project between
Antarctic images, both historical and that prevents significant melting, is to VUW, GNS Science, University of Otago,
recent. Thanks to Michelle Dow, ARC limit global warming to less than 2°C and US and Italian colleagues, to recover
Centre Manager, for her outstanding – the challenging target adopted by the a geological archive of warmer terrestrial
co-ordination of the move, and to Kosta worlds governments in Paris. Nancy climate on Antarctica 20-14 million years
Tashkoff (SGEES) for his help and Bertler and Rob McKay received the ago. Darcy also completed design and
support with the refurbishment. ARC’s 13th Marsden Fund grant for a fabrication with Websters, of a floating
new project “Predicting a sea change: barge platform for the Lake Ohau drilling
Overall, 2015 has been another highly- Antarctic ice-ocean interactions in a project undertaken in February 2016.
productive year for the ARC. It was warming world”. And last but certainly
a big year for postgraduate student not least Lionel Carter was awarded the Funding for Antarctic research in New
completions, with seven PhD theses Hutton Medal by the Royal Society of Zealand remains a bittersweet challenge.
and two MSc theses submitted. We look New Zealand for his career contribution While ARC staff continue to perform
forward to a new cohort of students in to understanding the evolution of New well in highly competitive contestable
2016. Our commitment to world-leading Zealand’s ocean environment. funds (e.g. Rutherford, Marsden), and
Antarctic and climate change research a new modest-sized philanthropic
that makes a difference internationally As always our science drilling team are fund provided by NZARI is a welcome
and in New Zealand is grounded in staying one step ahead of the game, by addition, the lack of medium to long-term
scholarly research published in leading developing the appropriate technology to funding security remains a considerable
scientific journals. Staff and students support present and planned projects. On risk as New Zealand attempts to sustain
were involved in 34 publications in top the books in 2015 was hot water drilling. its world-leading Antarctic research
international peer-reviewed journals, and The University approved the capital reputation.
as stated above we profile the impact of expenditure of $800,000 to build a new
these four papers published in Nature, hot water drill capable of penetrating Nevertheless, I wish to sign off on
Nature Communications, Geology, and 1000 m to access the cavity under the a positive note by acknowledging
Earth and Planetary Science Letters. Ross Ice Shelf. The system will be built the importance of our national and
at VUW, and commissioned on the ice international partners, and stakeholders,
Antarctic Research Centre Annual Review 2015
Designed and edited by Michelle Dow Our commitment to communicating in 2016 by ARC’s Alex Pyne and Darcy whose collaboration allows our talented
Contributions from Tim Naish, Nick Golledge, Andrew Mackintosh, Huw Horgan, the relevance of this research to the Mandeno, with support from the Korean staff and students to continue to produce
Lionel Carter, Rob McKay, Nancy Bertler, Gavin Dunbar, Alex Pyne, Michelle Dow
public and stakeholders was equally Polar Research Institute, Antarctica New high-quality, world-class research that
Front cover photo: Mawson Glacier, Antarctica - Richard Jones impressive, and its timeliness and Zealand, NZARI and the British Antarctic matters and makes a difference.
This page photo: An ‘apple’ shelter, Antarctica - Matt Vaughan (University of Otago)
Back cover photo: Ice cave, Antarctica - Matt Vaughan (University of Otago)
antarctic research centre annual review 2015 3
OUR MISSION AND
RESEARCH APPROACH
We believe our field of research provides exciting opportunities and
challenges attractive to young researchers, and is needed to provide a
sound basis for international climate change assessment and predicting
local impacts to enhance policy development for a more resilient New
“improve understanding
Zealand.
of Antarctic ice sheet and
The Antarctic Research Centre (ARC) is one of a number of the uncertainties around future climate and sea-level rise
centres of research excellence within the Faculty of Science at predictions. We improve understanding of the influence and climate processes and
Victoria University of Wellington and reports directly to the impact of Antarctic and Southern Ocean change on the global
Dean of Science. It is co-located with the School of Geography, climate system, especially the Southwest Pacific region and New
their influence on New
Environment and Earth Sciences, with which it shares academic Zealand. Our research is leveraged by very strong national and
staff and facilities. It also contributes to both undergraduate international collaborations and partnerships and world leading
and graduate teaching and supervision in the fields of in-house polar drilling technology provided by the Science Zealand and the global
sedimentology, glaciology, paleoclimatology and Antarctic Drilling Office, and is funded and supported through a range of
affairs. MBIE and Marsden programmes, Antarctica New Zealand and
climate system.”
private donations.
Rationale In summary our approach involves:
The warming trend observed over the past century and models a. The acquisition of past (paleo) observations of surface
of its future trajectory suggest that we are rapidly heading temperature, atmospheric circulation and composition
towards a climate last experienced more than 3 million years (greenhouse gases and aerosols), ice sheet, glacier, and sea-ice
ago - a time before our species had evolved. In order to assess variability, and oceanic conditions from geological and ice core
model-based climate projections, scientists are increasingly archives.
looking back to the future to gain insights into the likely
response of Earth’s climate in a world with high levels of b. Undertaking process studies of modern glaciers and glacial
greenhouse gases. Ice sheets and oceans are some of the slowest and marine systems.
responding elements of the climate system to an atmospheric
carbon dioxide perturbation - taking centuries to millennia to c. Integrating the observations and processes with numerical
play out, and are therefore potentially irreversible on human modelling to understand sensitivity and response of the
timescales. Reconstructing past climate conditions provides Antarctic ice sheet and climate system to the type of forcings
the only possible way to assess the long term “endgame” and feedbacks projected for the future.
(equilibrium response), that we will commit our planet
to this century based on the current warming scenarios - d. Then use those same models to improve future projections of
which virtually guarantee +2-3°C increase in global surface ice sheet contribution to sea-level rise and other changes in the
temperature. Past climate records also allow the role of Earth System.
anthropogenic influences to be determined in the context of
natural variability of the climate system on human timescales. e. Comparison and correlation with equivalent “far-field”
observations and reconstructions, of global extent, and within
the SW Pacific and New Zealand (e.g. records of global sea level
Outcome-based research and local New Zealand ocean and climate change).
Our research approach is policy-relevant and outcome focused. f. We disseminate our research findings through publications in
We reconstruct the response of the Antarctic and Southern the world’s leading scientific journals, and through education,
Ocean to past climate change, that is similar to that projected communication and outreach to the public, practitioners and
for the coming centuries by the Intergovernmental Panel on policy makers.
Climate Change (IPCC). We do this to improve the performance
Hut Point, Ross Island, Antarctica
of the models assessed in the IPCC reports in order to reduce Photo: Michelle Dow
antarctic research centre annual review 2015 5
EMISSIONS REDUCTIONS
increasingly wondering how the expected This process commonly takes hundreds chain of events is set in motion that
rise in temperature will affect the largest of experiments to get right, and with contributes 40 cm to global sea-level rise
ice sheet on Earth, the Antarctic ice individual simulations often taking by 2100 without emission reductions, and
ESSENTIAL TO AVOID
sheet. Considered for a long time to be several days to complete, this tuning ultimately leads to increases in global sea
relatively stable, with its great expansions procedure can take many months. level of up to 3 m by 2300. Significantly,
and contractions mostly controlled by the simulations showed that the only way
SEA-LEVEL RISE changes in the Earth’s orbit on time But by building on a methodology to avoid a substantial contribution to sea
scales of thousands of years, the Antarctic established and refined over several level from Antarctica is to limit global
ice sheet is now revealing a much more years, and using an internationally warming to less than 1.5–2 degrees above
dynamic side – one that has the potential developed numerical ice sheet model, present temperatures, the level agreed by
to drastically reshape our coastlines over Nick Golledge began tackling this subject governments at the 2015 UN Conference
coming decades. as part of his Marsden Fast-Start project. of Parties in Paris.
Working with climate modellers and
Together, the two parts of the Antarctic geologists in the USA, Australia, and New Several aspects of the study have
ice sheet that make up the continent – Zealand, including ARC Director Tim immediate policy relevance. Firstly, IPCC
the West Antarctic and East Antarctic Naish and Richard Levy (GNS Science), is currently underestimating Antarctica’s
ice sheets – contain enough freshwater Nick tuned his model to simulate the contribution to sea-level rise by 2100.
to raise global sea levels by nearly 60 m. Antarctic ice sheet under past and Secondly, the greenhouse gases we emit
But how much of this might be released present-day conditions as closely as today will commit the planet to a series
over coming decades is an area of large possible, and then used climate model of global environmental impacts that
uncertainty, and consequently the focus predictions for the future to see how the will continue for thousands of years into
of very active current research that ice sheets would behave. the future. Thirdly, although the ‘end-
can only be tackled with sophisticated game’ of the ice sheet response may take
numerical models that can simulate the The results, published in the journal millennia, the initial effects will be felt in
entire continent. Nature, were startling – under a the next few decades, as rising sea levels
Wilhelmina Bay, Antarctic Peninsula - Photo: Nick Golledge greenhouse gas emissions scenario in lead to more frequent coastal inundation
One of the most difficult aspects of using which no mitigation takes place, nearly and damage to property.
In a recent report “Preparing for Sea- statement. “It is certain that the sea coastal areas will be affected, and how a computer model to predict the future, all floating ice in Antarctica is lost by the
Level Rise (SLR)”, The NZ Parliamentary is rising and will continue to do so for we should prepare.” As atmospheric however, is the careful ‘tuning’ that is end of the century. Without these ice CONTACT: [email protected]
Commissioner for the Environment, centuries to come. But much is uncertain CO concentrations continue to rise, required to allow the model to accurately shelves to hold back the grounded ice on
2
made the following important – how rapidly it will rise, how different a global community of glaciologists is simulate past changes and the present. the rest of the continent, an unstoppable
EVIDENCE OF RUNAWAY
modelling. Importantly, it shows that the Ross Sea prior to the Holocene and may emission pathways (e.g. see above)
rate of glacier thinning events, similar have contributed to rapid global sea-level predict an on-going commitment to many
to those observed by satellites in rapidly rises (e.g. meltwater pulses) of up to 4 m metres of global sea-level rise if Earth’s
ANTARCTIC ICE LOSS IN THE
changing parts of Antarctica today, may per century. climate warms more than 2°C above
continue unabated for centuries. pre-industrial levels – the United Nations
Of concern is a growing realisation that “safe” climate limit. Together, these two
RECENT PAST
Working on ANDRILL site survey cores processes of marine ice sheet instability geological studies provide the first direct
collected beneath the Ross Ice Sheet, in may cause significant ongoing loss of evidence that this process has actually
the vicinity of the proposed Coulman Antarctic ice sheet mass for millennia occurred in the past.
High drilling project, the ARC’s Rob to come even if the climate system
Sea-level rise in coming centuries will recent ARC publications have highlighted Using results from the newly developed McKay, Nick Golledge, Tim Naish, Gavin stabilises. Studies using ice sheet model CONTACT: [email protected]
become increasingly dominated by glacier the role that this instability mechanism Beryllium-10 (10Be) dating facility at Dunbar, and MSc graduate Sanne Maas simulations for future carbon dioxide [email protected]
[email protected]
and ice sheet contributions. However, played in the retreat of the Antarctic ice VUW, Richard showed that Mackay led a paper in Geology that showed this
predicting these contributions remains sheet in the Ross Sea region following the Glacier, an outlet of the East Antarctic Ice process of marine ice sheet instability was
challenging because several processes last ice age (~20,000 years ago). Both of Sheet, underwent rapid thinning around widespread during the deglaciation in
that determine glacier response are these studies imply that once triggered, 7,000 years ago, in a climate similar the central regions of the Ross Sea. They
poorly understood and not well resolved marine ice sheet retreat could be rapid to present. This is arguably the finest obtained an age for the retreat of the
in numerical models. Such processes and persist for centuries without further 10Be dataset to come from Antarctica, ice sheet in central Ross Sea more than
may induce threshold ice sheet response, climate forcing. with ~ 40 high precision ages tightly a thousand years earlier than previous
resulting in abrupt, runaway ice loss. constraining the behaviour of Mackay studies from coastal sites in the Western
Of particular concern is the ‘marine ice Richard Jones (a current ARC Glacier between 20,000 years ago and Ross Sea. Supporting ice sheet model
sheet instability’, where initial retreat of postdoctoral fellow) led a study published the present. It is also the first study to simulations indicate that substantial ice
an ice margin, in contact with the ocean, in Nature Communications, with his PhD unambiguously link geological evidence loss could have occurred in the central
into a deepening valley below sea-level supervisors Andrew Mackintosh, Kevin of rapid ice surface lowering to the
Kevin Norton and Chris Fogwill sampling for
may lead to rapid, unabated ice loss. Two Norton (SGEES) and Nick Golledge. marine ice sheet instability via numerical
cosmogenic dating - Photo: Richard Jones
antarctic research centre annual review 2015 7
TEMPERATE GLACIERS CAN
address two of New Zealand’s most iconic week or so, and extreme rates of melting, stabilized. This finding, published in
glaciers: Franz Josef and Tasman. this behavior will continue into the Earth and Planetary Science Letters
future, allowing rapid transport of ice (Horgan et al., 2015), has dramatically
ACCELERATE DRAMATICALLY On the wetter side of the Southern Alps, to the ablation zone, where a warming changed our view of the dynamics of this
Franz Josef Glacier experiences vast climate is driving glacier retreat (Kehrl et and similar glaciers (the big and slow can
amounts of precipitation and meltwater al. 2015). still surprise).
is literally everywhere on Franz Josef
- above, inside and beneath it. MSc Despite sharing the main divide with The next challenge is to learn more
graduate Laura Kehrl and her supervisors Franz Josef Glacier, Tasman Glacier is a about glacier accelerations using these
Brian Anderson, Ruzica Dadic, Huw different beast, with slower ice-flow rates observations and appropriately include
Horgan and Andrew Mackintosh, and, it was considered, less interesting these processes in the numerical models
recently undertook a study, published dynamics. However, Tasman warrants that we are using to predict glacier
in the Journal of Glaciology, of Franz study as it contains about one-third of all response to climate change.
Josef Glacier by installing a series of glacier ice in New Zealand, and feeds the
GPS units on the surface, with the aim of Waitaki hydroelectric power system. CONTACT: [email protected]
understanding how this glacier responds
to water inputs. Water can influence When processing the records from GPS
glacier sliding in a counter intuitive units installed on the glacier surface,
way. For example, water usually makes accelerations in velocity of up to 36 times
the largest difference in spring (rather stood out. These are the largest rain-
than summer) when water confined induced accelerations ever reported in
beneath glaciers floats the overlying literature. Further analysis showed that
Franz Josef Glacier, New Zealand - Photo: Brian Anderson ice, increasing the rate of ice flow. after heavy rain the glacier lifts off its
However, at Franz Josef Glacier, Laura bed by over 50 cm as cavities form due
How fast can glaciers deliver ice to the place at the base of glaciers and ice provide us with some unprecedented discovered that the glacier still responded to high water pressures. The ice moved
sea? This question lies at the heart of sea- sheets making them exceedingly difficult observations of glacier acceleration due to increases in water flow at the glacier fastest while the cavities were forming,
level rise uncertainty. However, many of to observe and model. New studies in to changes at the glacier base. These bed in late summer. With heavy rainfall and settled down to a still enhanced
the processes that control ice motion take the Southern Alps, New Zealand, now observations span the main divide and events occurring at Franz Josef every sliding velocity after cavity growth had
MANAGING AND PROTECTING
when more intense typhoon floods
formed destructive turbidity currents - a
possible effect of regional climate change.
THE GLOBAL DEEP OCEAN
Recognising that science papers are not
easily consumed by the public, ICPC
TELECOMMUNICATION
focuses on science communication. It
collaborated with the United Nations
Environmental Programme to produce an
CABLE NETWORK easy-to-read booklet Submarine Cables
and the Oceans (available at https://
www.iscpc.org/publications/). In the
financial year 2012-13, over 74,000
Research provides skills, knowledge and of information and a means to distribute peer-reviewed papers to assure quality downloads were recorded attesting to
experience with wide applications in the that information around the planet at and independence. Thus, the research successful outreach. It helped that the
outside world. For the past decade, Lionel lightening speed. Today, 98% of voice, contributes to our knowledge of deep- booklet was free.
Carter, has worked with the submarine data, video and Internet traffic is via ocean processes such as landslides and
cable industry to assess risks to the global submarine cables. Thus protection of this turbidity currents, the main causes CONTACT: Lionel [email protected]
network of fibre-optic cables posed by critical infrastructure is paramount. of cable damage. Emphasis has been
natural hazards including climate change. on Taiwan because of its extreme
Why is this significant? The development Enter the International Cable Protection seismicity, typhoon-charged weather and
of the Internet in the late 1980s coincided Committee (ICPC) - a not-for-profit position at a major cable route. In 2006, A fibre-optic cable (extending from the lower
with the first trans-oceanic fibre-optic forum for the cable industry and other earthquake-triggered landslides and right side) is recovered for repair from about
4000 m depth off Taiwan. It is damaged by
cable. It was a fortuitous marriage that groups including the New Zealand turbidity currents caused 22 cable breaks
a mass of fishing debris, plastic and wood
changed the world. Suddenly, there was government. Natural hazard research and temporarily isolated SE Asia. More
swept from the continental shelf by a turbidity
a mechanism to generate vast amounts supported by the ICPC is documented as damage occurred from 2009 onwards current -Photo: Lionel Carter
antarctic research centre annual review 2015 9
PAST CLIMATE WINDOWS
Pliocene Ice-Sheet Model
Intercomparison Project
(Antarctica)
PROVIDE IMPROVED VIEW OF
One of the many significant challenges
involved in making interpretations from
THE FUTURE
computer models lies in knowing which
aspects of the results are influenced
by the model itself. To overcome these
kind of obstacles, many modelling
Drilling to find the triggers retreat in Ross Sea since the Last Glacial improve projections of West Antarctic groups employ ‘intercomparison’
for Antarctic ice sheet Maximum, and providing a stratigraphic contributions to future sea-level rise. techniques, in which different models
collaspe record of oceanographic and ice sheet are used to simulate the same scenario.
change over the last ~2 million years First publications from our group focused Nick Golledge participated in one
After several years of development, from long piston cores collected on the on the calibration of the record with the such exercise, in which the focus lay
the ARC-led international proposal to continental rise. While these records will modern observations (Neff et al. 2015, on determining the extent of Antarctic
drill a series of six geological cores in be important paleoclimatic archives in Tuohy et al. 2015, Emanuelsson et al. ice sheets during the mid-Pliocene
the Ross Sea, has now officially been their own right, they will also form the 2015) which allows us to take advantage period, when global climate was much
endorsed for future drilling by the basis for interpreting the longer cores to of the high resolution nature of the warmer than today. Although there
International Ocean Discovery Program be collected as part of the future IODP deeper record. With the age model now were differences in outcome predicted
(IODP) – arguably the world’s premier drilling in this region. Geophysical data in place, a large body of publications by the six different ice-sheet models,
geoscience programme. The proposal was was also collected by KOPRI scientists are waiting in the wings for submission an analysis of the results, published in
given the highest possible ranking for that ultimately proved invaluable in over the coming months. To follow our The Cryosphere (de Boer et al. 2015),
scientific merit, and is currently awaiting obtaining final scientific approval for the progress during this exciting time, please identified regions where ice sheet changes
scheduling to drill by the JOIDES IODP Ross Sea proposal. check out www.rice.aq were consistent between all models.
Resolution research vessel, hopefully This kind of work has great potential for
coinciding with the drill ship’s visit to our CONTACT: [email protected] refining uncertainty estimates on future
region in 2018. The last major drilling PAGES project - 2000 year ice sheet predictions.
efforts in the Ross Sea were the ANDRILL temperature reconstruction
cores in 2006-07, which provided the RICE ice core provides of Antarctica CONTACT: [email protected]
first direct evidence of ice sheet retreat insights into sensitivity of
events over the past 20 million years ice sheets to ocean warming The ice core team contributed high
from the inner Ross Sea continental shelf. resolution ice core records from three
This new project aims to build on these Over the past two years, the international regions - Victoria Lower Glacier,
ice sheet “collapse” ANDRILL records by Roosevelt Island Climate Evolution Mount Erebus Saddle and Whitehall
drilling on the outer Ross Sea continental (RICE) team has completed the Glacier to the Antarctic 2000 year
shelf and the adjacent deep sea to continuous flow analysis of the 763 m (2ka) temperature reconstructions. The
understand the oceanic triggers that deep ice core and analysed thousands reconstruction considers well dated,
may have initiated past collapse events of discrete samples for analysis on annually resolved records and assesses
at the continental shelf edge, as well as gas content, dust, volcanic ashes and the quality of each data set and provides
documenting the oceanic responses to geochemical composition leading to a a weighing factor based on the quality.
large shifts in Antarctic ice volume. remarkable data set of exceptional dating The compilation is a contribution to
precision. The evolving RICE data set the PAGES 2ka reconstruction of global
provides a highly resolved reconstruction temperatures which aims to inform the
Working with Korea to of the deglaciation in the Ross Sea region IPCC and provides an important tool
recover climate archives over the past 80,000 years and perhaps to assess model performance for future
from the Ross Sea beyond. This region is particularly projections. The ARC was the only New
important as the Ross Sea is a major Zealand group who contributed data to
Analytical work began on the cores and drainage pathway of West Antarctic ice the Antarctic 2ka array and represents
geophysical data collected as part of a and is one of four sources of Antarctic 30% of the data set spanning at least
New Zealand-Korean research voyage Bottom Water formation, an important 100 years. The RICE group is working
to the Ross Sea in 2014/15. Gavin engine of the global ocean conveyor and enthusiastically to also include the RICE
Dunbar and MSc student Olya Albot global heat budget. Moreover, the area temperature and snow accumulation
participated in the research expedition, is influenced by meltwater originating reconstructions in time for the 2016
while Rob McKay and Olya visited from the rapidly changing Amundsen / publication of the array reconstruction.
the Korean Polar Research Institute Bellingshausen Sea shelf regions, and
(KOPRI) during 2015 to help sample and experienced recent sea-ice growth. The CONTACT: [email protected]
interpret the cores. The sediment cores RICE record provides new and unsettling
obtained will cleary address a range of insights into the sensitivity of the Ross
scientific objectives, most notably better Ice Shelf and West Antarctic Ice Sheet Olya Albot in Korea describing the KOPRI
constraining the timing of ice sheet to ocean warming and will help us to cores - Photo: Olya Albot
antarctic research centre annual review 2015 11
HOW THE DEEP SOUTH
eventually dominate sediment deposits
on the extensive Campbell Plateau.
This means a change in the base of the
AFFECTS CLIMATE CHANGE
marine food chain, the consequences of
which have yet to be determined. The
new data improves interpretation of the
IN NEW ZEALAND environmental conditions that favoured
coccolith blooms in previous warm
periods. Then, the uppermost ocean over
Campbell Plateau was a semi-stable layer
Did a previous collapse of the back blocks of the Wanganui Basin, to climate (especially rainfall) in the of nutrient-rich water up to 4oC warmer
the Antarctic ice sheet cause west of Taihape. Already world renowned surrounding catchment. Some of this than now - conditions we appear to be
abrupt climate change in for its geological record of sea-level research was published in the journal approaching today.
New Zealand? change over the last 5 million years, the Marine and Freshwater Research (Cossu
new cores are providing a remarkably et al. 2016). Studies of past ocean environments are
Ice cores show that warming in detailed picture of the frequency and needed to predict future responses to
Antarctica at the end of the last ice age magnitude of sea-level change for Recently completed PhD student Heidi increasing warmth. Studies of the past
was interrupted by a cold event, known as this important time that is relevant to Roop, combined elements of lake identify natural climatic cycles and
the Antarctic Cold Reversal, about 14,000 sea-level predictions for the coming process research and analysis of the reveal the effects of long-term change.
years ago. Geological evidence shows centuies. Georgia has reconstructed last 1400 years of the environmental In the case of the Southern Ocean, it
that glaciers in New Zealand readvanced local water depth changes using depth- history from short sediment cores. Heidi has buffered the full impact of modern
during this interval, but the cause of such dependent fossil plankton assemblages also had two papers published, one in change by soaking up about 90% of the
cooling remains a mystery. Supported (foraminifera) with Hugh Morgans (GNS Sedimentology and the second accepted extra heat and 30% of the carbon dioxide
by a NZARI project, postdoctoral fellow Science) and sediment grainsize. In in the Journal of Paleolimnology that produced by human activities. This begs
Shaun Eaves is working with Andrew collaboration with Christian Ohneiser combined many aspects of our research the question “What is the natural cycle
Mackintosh and Brian Anderson to and Claudio Tapia-Orellana from from geochronology, sedimentology, of this phenomenon?” This question is
examine the spatial pattern of cooling in University of Otago and VUW’s Gillian hydrodynamics and meteorology to answered in a study published in Earth
New Zealand as recorded by mountain Turner, Brent Alloway and Diane Seward, demonstrate that Lake Ohau preserves and Planetary Science Letters (Skinner
glaciers, using a combination of an age model that will constrain the rate a complex, but annually-resolved record et al. 2015) that examines the passage of
cosmogenic surface exposure dating and of change is being developed. In 2016, of environmental change. Heidi was heat and gas-bearing surface water into
glacier modelling. In contrast to some Georgia will travel to Stanford University able to identify three primary types of the ocean’s interior - a process termed
previous work, their initial findings show to undertake geochemical measurements annual layering associated with different ventilation - since the last Ice Age, 18,000
that New Zealand was 2-3oC colder than on the foraminifera in Rob Dunbar’s climate regimes; large flood events years ago. At that time, much of the
present and that this cooling caused laboratory. The next step will involve deposit relatively thick, homogeneous Pacific interior was less well ventilated
glacier advance across the Southern Alps working with Peter Kamp (University of layers, frequent smaller flood events in than today. As climate warmed, changes
and central North Island. These results Waikato) and Michelle Kominz (Western a year deposit a number of very thin silt in winds and ocean currents enhanced
are being used to evaluate global climate Michigan University) to extract the layers and years without significant floods ventilation. As is typical of scientific
model simulations in order to test the influence of tectonics on the global sea- deposit a simple coarse/fine couplet. The research, as one question is resolved,
hypothesis that this abrupt Southern level cycles. deposits of large floods are particularly new questions arise. In this case, they are
Hemisphere climate event was caused intriguing as they appear regularly in the “Has ventilation increased under modern
by a large release of meltwater from CONTACT: [email protected] Ohau record back to ~1350 AD and prior changes such as the poleward migration
Antarctica. to ~950 AD but with a 400 year absence of wind regimes?” and “What is the
in the middle ages, suggesting a shift in long-term outlook of heat/carbon dioxide
CONTACT: [email protected] Lake Ohau’s annual record climate regime at that time. uptake by the Southern Ocean?”
of environmental change
CONTACT: [email protected] CONTACT: [email protected]
Ancient sea-level change Our Lake Ohau, New Zealand research
revealed in the geology of continued to build steadily towards
Whanganui our Marsden-funded deep drilling Ocean productivity changes
programme which was rescheduled to around New Zealand
Tim Naish, Gavin Dunbar and Rob early 2016 (read about it in next year’s
McKay, together with their students report! Or for a sneak preview http:// Plankton in the Southern Ocean, off the
Juliet Sefton (MSc completed) and drill.gns.cri.nz/DrillNZ/Lake-Coring/ South Island, New Zealand are changing
Georgia Grant (PhD current), have been Lake-Ohau-Climate-History/Latest- in response to a warming ocean. This
taking a closer look at global sea-level News). Detailed analysis of the modern study, led by PhD student, Bella Duncan,
changes the last time Earth was 2-3oC sedimentary processes based on our took advantage of new data to refine a
warmer and carbon dioxide levels in the monitoring programme continued model that shows increasing numbers
atmosphere were the same as today - in collaboration with the Australian of coccoliths - a plant plankton species
approximately 3 million years ago. This Maritime College. These processes help composed of white platelets of calcium
Marsden-funded project has recovered determine how the laminated sediments carbonate such as those that form Tasman Glacier, New Zealand
two high-quality geological drill cores in accumulating on the lake floor relate the White Cliffs of Dover, UK - will Photo: Brian Anderson
antarctic research centre annual review 2015 13
ASSESSING THE STATE OF
GLACIERS AND ICE SHEETS
Retreating New Zealand Imaging the West Antarctic survey for a potential drilling target for an
glaciers Ice Sheet grounding line archive of climate and ice sheet history.
CONTACT: [email protected]
Global mountain glaciers are The Siple Coast of the West Antarctic Ice
experiencing unprecedented retreat, and Sheet has preoccupied the glaciological
New Zealand glaciers are no exception. community since the potential for Sensitivity of the Southern
Brian Anderson, Huw Horgan, Andrew rapid, marine ice-sheet retreat was first Ocean to meltwater from
Mackintosh and Ruzica Dadic coordinate postulated in the late 1960s and early Antarctica
our Southern Alps glacier monitoring ‘70s. Central to the current understanding
projects, which contribute to global of this instability hypothesis is the Currently, melting ice in Antarctica
efforts to document and understand these relationship between ice flow across contributes a relatively small, but
dramatic changes. In collaboration with the ice-sheet-ice-shelf transition (the increasing, amount of freshwater to the
the University of Otago, our direct mass grounding zone), oceanic forcing, and surrounding ocean. The effects that this
balance programme at Brewster Glacier is ice thickness. During the 2015-2016 freshwater input might have on ocean
now in its 12th year. We are also working Antarctic season VUWAE 60 included stratification, and thence surface climate,
in partnership with NIWA to monitor a geophysical team on the Siple Coast is not well known, but previous ARC-
New Zealand glaciers from light aircraft grounding zone of Kamb Ice Stream. led research has shown that ice-ocean
in the annual ‘end-of-summer-snowline’ This work complements ongoing work feedbacks could have played a significant
flights which have been ongoing since on the adjacent Whillans Ice Stream, and role in accelerating ice-sheet retreat
1976. We have been developing new wider projects on the Ross Ice Shelf in during the last glacial termination. To
techniques to allow precise positioning collaboration with colleagues from the test this hypothesis, researchers at the
of the images taken during these flights, university’s of Otago and Canterbury, University of New South Wales, Sydney,
which allows very accurate digital supported by NZARI, the MBIE Past working with Nick Golledge, used a
reconstructions of the glacier surfaces. Antarctic Climates Programme and the global climate model to simulate the
Our new PhD student Lauren Vargo will Marsden Fund. effects of releasing freshwater into parts
be using these data to measure snowlines, of the ocean around Antarctica where
terminus positions and to reconstruct ice At present the Siple Coast ice streams currently the greatest glacier recession
volume changes. Finally, our network of drain approximately one third of the West is taking place. The results, published in
seven time-lapse cameras overlooking Antarctic Ice Sheet. Kamb Ice Stream the AGU journal Earth’s Future (Fogwill
four glaciers has now captured ~40,000 stands out amongst its neighbours et al. 2015), showed that in all cases the
images which allow quantification and as its flow ceased approximately 160 release of freshwater into the Southern
exploration of the processes driving ice years ago making it a poster child for Ocean triggered greater stratification
loss in the Southern Alps. natural variability in ice flow. The five and a warming of water that was greatest
member VUWAE team on Kamb Ice in the upper 1000 m. Significantly, the
Built on a database of over 1000 snow Stream was one of the furthest-afield simulations showed that even localised
depth and ice melt measurements, deployments supported by Antarctica freshwater injections led to rapid
historic maps of glacier positions in the New Zealand in recent years at a distance subsurface warming around large sectors
late 1800s, and recent measurements of approximately 900 km from Scott of the continent.
of glacier termini, Brian, Andrew, and Base. The team, led by Huw Horgan and
colleagues from NIWA have developed supported by Darcy Mandeno deployed CONTACT: [email protected]
a numerical model which has been used for six weeks. During this time, they
to predict Southern Alps ice loss by the performed geophysical experiments to
year 2100. The results are dramatic - image the ice sheet and the underlying
even with a ‘middle of the road’ emission sediments using active-source seismic
scenario resulting in a local warming of and radar methods. Targets included
2.4˚C, ice volume reduces to 12 km3 in sedimentation at the grounding zone,
the central Southern Alps, a loss off 68% subglacial drainage at the ice stream
from ice volume in 2000. In this scenario, margin, and site surveying for the
iconic Fox and Franz Josef glaciers upcoming NZARI hot water drilling
retreat to small remnants high in the programme. The team also used seismic
mountains. surveying to image deeper sedimentary
structures beneath the stagnant Ross
CONTACT: [email protected] Ice Shelf downstream of the Kamb Ice An iceberg trapped in the sea ice, Antarctica
Stream. These data will serve as site Photo: Matt Vaughan (University of Otago)
antarctic research centre annual review 2015 15
DEVELOPING NEW DRILLING
TECHNOLOGIES
The Science Drilling Office is providing critical
support to a range of new projects.
The Science Drilling Office (SDO) their drilling capabilities and successfully for a commissioning season near Scott
is hosted in the Antarctic Research drilled commercial geotechnical coring Base on the McMurdo Ice Shelf in the
Centre and led by Alex Pyne, SDO contracts both at Scott Base and 2016/17 season. The drill design will be
Director and ARC Projects Manager, McMurdo Station this last Antarctic closely based on current hot water drill
and Darcy Mandeno, Operations and summer season with excellent recovery systems that have been developed by
Field Engineer. Alex and Darcy have had of basalt lava, scoria and preserved the British Antarctic Survey who have
another busy year supporting three field interstitial ice. This technology will be been successfully drilling hot water holes
projects in preparation and execution. refined in 2016 and then used for coring in both the Antarctic ice shelves in the
at Friis Hills in the McMurdo Dry Valleys Weddell Sea area and the Greenland Ice
as part of a joint University of Otago, Sheet.
Drilling holes for seismic
ARC, GNS Science project together with
surveys
international collaborators from Italy and CONTACT: [email protected]
the USA.
Darcy’s primary work was the
construction of a small hot water drill
designed to make 30 m deep holes in
Building a barge
firn (compacted snow) for explosives
on over snow seismic surveys. The drill,
The other major project in preparation
which uses a large commercial hot water
this year with WD&E has been the
pressure washer as it’s heat and pressure
design and preparation for recovering
components, was modified and deployed
continuous sediment cores from Lake
on purpose designed lightweight ski/
Ohau, New Zealand. Darcy provided the
sledges towed by skidoos at the Kamb
detailed design work for the purpose built
Ice Stream. Darcy operated the hot water
barge construction that was fabricated
drill with Huw Horgan’s seismic team
in the first half of the year and Alex and
during the three-month field season in
Tony Kingan (WD&E) worked on the
2015-16 at the Siple Coast, Antarctica.
design of the deck equipment to manage
and deploy the lake riser casing, a four
Bigger and better anchor mooring system and drill pipe
in water depths up to 100 metres. This
In collaboration with Webster Drilling project operation scheduled February/
and Exploration (WD&E) the SDO have March 2016 had at the time of writing
also been developing new technology and successfully recovered duplicate cores to
drilling capability. In the early 2000’s the 42 m below the lake floor in water depths
ARC carried out core drilling in Antarctic of 70 m.
permafrost using a novel approach with
chilled compressed air flushing to avoid
the use of contaminating drilling liquids. More hot water drilling
From this experience we have been able
to improve this approach with theoretical A new project for the SDO in 2016 will
calculations and design then enabling be the development of a 1000 m depth
WD&E to develop new equipment with capable hot water drill to be first used
larger air compressors, better air-cooling for the New Zealand Ross Ice Shelf
systems and better dimensioned coring project (RIS). The ARC has been granted
barrels appropriate for compressed air a major VUW CAPEX of $800K to
Darcy Mandeno operating the seismic hot
operations. Webster drilling carried out fund this development and equipment water drill, Siple Coast, Antarctica
the engineering development as part of purchases were started in late 2015 Photo: Matt Vaughan (University of Otago)
antarctic research centre annual review 2015 17