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Victoria University Antarctic Research Expedition Science and Logistics Reports 2009-10: VUWAE 54

IMMEDIATE SCIENCE REPORT K049: NZ ITASE

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IMMEDIATE SCIENCE REPORT

K049: NZ ITASE

Antarctica New Zealand 2009/10

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1. Scientific Programme

a. Research Objectives

Unprecedented changes are occurring in the Earth's climate. The current decade was the warmest on record since 1880 AD. The global average surface temperature has increased, especially since about 1950 with 100-year trend (1906–2005) of 0.74°C ± 0.18°C (IPCC, 2007). Although the scientific evidence of global warming is now widely regarded as unequivocal (IPCC, 2007), predicting regional impacts still poses challenges. Especially, conclusions of the Southern Hemisphere record are limited by the sparseness of available proxy data at present (Mann & Jones, 2003).

While meteorological records from instrumental and remote sensing data display the large intercontinental climate variability, the series are insufficient to infer trends or to understand the forcing, which renders prediction difficult (Jones et al., 1999; Mann & Jones, 2003). The long ice core records from the Antarctic interior and Greenland revolutionised our understanding of global climate and showed for the first time the occurrence of RCE (Rapid Climate Change Events, for review e.g. Mayweski and White (2002)). To understand the drivers and consequences of climate change on timescales important to humans, a new focus of ice core work is now moving towards the acquisition of 'local' ice cores that overlap with and extend the instrumental records of the last 40 years back over the last several thousand years (Mayewski et al., 2005).

This has been a key motivation behind the US-led International Transantarctic Scientific Expedition (ITASE) of which New Zealand is a member (Mayewski et al. 2005). The NZ ITASE objective is to recover a series of ice cores from glaciers along a 14 degree latitudinal transect of the climatically sensitive Victoria Land coastline to establish the drivers and feedback mechanism of the Ross Sea climate variability (Bertler et al., 2004a; Bertler et al., 2004b; Bertler & 54 others, 2005; Bertler et al., 2005a; Bertler et al., 2005b; Bertler et al. 2006, Patterson et al., 2005, Rhodes et al. 2009).

Due to logistical constraints by Antarctica New Zealand, the field deployment planned for 2009/10 was cancelled and a substantially reduced programme was carried out.

b. Brief Methodology

Automatic weather station set-up, maintenance, and data retrieval

Since 2004/05 we deployed an automatic weather station on Evans Piedmont Glacier and since 2007/08 also at Skinner Saddle. The data permit the calculation of transfer functions between ice core proxies and meteorological parameters, such as temperature, precipitation, meso-scale atmospheric circulation pattern, katabatic winds, and seasonality of snow accumulation. In addition, a new snow accumulation sensor and high precision snow temperature probes allow us to monitor snow accumulation rates, the potential influence of snow loss through sublimation, wind erosion or melt, and the quality of preservation of the meteorological signal in the snow. Furthermore, the data allow us to estimate the uncertainty of re-analysis data (NCEP/NCAR and ERA-40 data) in the region. At the request of Antarctica New Zealand, the automatic weather station was retrieved from Skinner Saddle this year.

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Fig. 1: Automatic weather station at Skinner Saddle

Fig. 1: Automatic weather station at Skinner Saddle

Submergence Velocity Measurements at Victoria Lower and Evans Piedmont Glacier

The response time of a glacier to changes in accumulation or ablation is dependent on the size and thickness of the ice mass. In general, the response time of cold-based glaciers is positively correlated with the size of its ice mass, leading to long response times in Antarctica. For glaciers in the McMurdo Dry Valleys, with lengths on average of 5-10km and flow rates of 1 to 3 m/a, the response times are thought to range from 1,500a to 15,000a (Chinn, 1987; Chinn, 1998). Consequently, annual variations in surface elevation may only reflect changes in loss rates. As a result surface measurements of mass balance are difficult to interpret in terms of long-term mass balance (Hamilton & Whillans, 2000). This is especially the case in places like the McMurdo Dry Valleys where mass loss is thought to be predominately due to sublimation at ice cliffs and glacier surface caused by wind and solar radiation (Chinn, 1987; Chinn, 1998). For Victoria Lower Glacier (VLG), two mass balance measurements are available in the literature for 1983 and 1991 based on ice cliff characteristics and the motion of the glacier snout (Chinn, 1998). The measurements indicate that VLG was advancing 1.24m/a into Victoria Valley during this time period. However, the small number of observations (2) and the cliffs sensitivity to sublimation (contemporary surface ablation) result in a high uncertainty of longer term mass balance. To determine the longer-term mass balance of the glaciers, unaffected by annual surface variations, three 'coffee-can' or 'submergence velocity' devices (Hamilton et al., 1998; Hamilton & Whillans, 2000) were deployed at Victoria Lower Glacier in 1999/2000 and two at Evans Piedmont Glacier in 2004/05. These are annually re-measured to monitor mass balance changes.

Fig. 2: Submergence Velocity Measurements at VLG

Fig. 2: Submergence Velocity Measurements at VLG

Snow Sampling for Aeolian Material

As our drilling programme had been postponed for a year, Dr. Tim Haskell (PI of K131) kindly allowed Holly Winton to join his group to conduct her research project. Her project focuses on iron fertilisation of the Ross Sea region. Fine-grained aeolian dust (<10 0m) is believed to be a significant source of iron (Fe), which is the bio-limiting nutrient required for phytoplankton growth in the McMurdo Sound, Antarctica. The dust accumulates on sea ice and is added to the ocean each year when the ice breaks up. This 'fertilisation' of the ocean results in vast phytoplankton blooms that alter the food web and generate large volumes of biogenic sediment. In spite of the apparent importance of aeolian dust in 'biogeochemical cycling' in the McMurdo Sound, the details of the interdependence of the geological processes that supply the Fe and the page 3 resulting plankton growth are poorly understood. This project aims to quantify aspects of this biogeochemical cycle for the first time by analysing the physical (size distribution, abundance and variability) and chemical (total and "bio-available" Fe content) properties of the aeolian dust blown off the Antarctic continent, deposited and trapped in coastal snow and ice in the McMurdo Sound region. Snow samples from McMurdo sea ice were collected this season for these measurements with the intention of publishing the results in an internationally peer-reviewed journal and presenting them at the Antarctica New Zealand conference.

Figure 3: Satellite image of McMurdo Sound showing snow sampling sites in November 2009. Red dotes: Sampling sites. Blue dote: Base camp. North of the yellow line dark areas denote first year sea ice, while lighter areas denote multi-year ice. Yellow outline marks the continental and sea ice edge.

Figure 3: Satellite image of McMurdo Sound showing snow sampling sites in November 2009. Red dotes: Sampling sites. Blue dote: Base camp. North of the yellow line dark areas denote first year sea ice, while lighter areas denote multi-year ice. Yellow outline marks the continental and sea ice edge.

c. What were the key achievements of your visit? Include any key preliminary findings that are of particular interest.

  • Automatic weather station set-up, maintenance, and data retrieval:

    Weather station data were downloaded and the instruments were serviced

  • Submergence Velocity Measurements at Victoria Lower and Evans Piedmont Glacier

    High resolution GPS measurements were conducted and the devices were serviced

  • Snow sampling for aeolian material

    An excellent spatial coverage of 55 snow samples were collected along three transects on the McMurdo sea ice (Figure 3). Sampling was carried out using ultra clean methodology to prevent contamination from personnel, sampling equipment and sample bottles. Two samples at each site were collected and duplicates of these taken at every second site to evaluate local and regional scale variability. First, snow samples from the snow surface to a depth of 2 cm above the sea ice (to prevent sampling saline snow), for elemental concentration and bio-availability measurements of dust were collected in pre-acid washed Nalgene polypropylene 500 ml or 1000 ml bottles. Second, larger volume samples of the full snow depth were collected for dust concentration and grain size measurements.

Figure 4: Dust layers in snow. A) First year ice downwind of Black Island, B) First year ice downwind of Black Island.

Figure 4: Dust layers in snow. A) First year ice downwind of Black Island, B) First year ice downwind of Black Island.

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2. Collaboration

Indicate any international collaborators who were part of your event. Include information about the organisation where the collaborator works and their position. If the collaborator is supported by an international grant or their host organisation please outline the details of this.

N.A. – Postponed to 2010/11

3. Publications

As part of the measurement of research outputs that we are now undertaking, it is important that all your publications for the past year are included as these will be used for searching the Web of Science for citation data. Note that reprints of any publications resulting from work supported by Antarctica New Zealand are to be forwarded to the Science Advisor at Antarctica New Zealand. These are kept in a reprint collection for reference, recorded in our bibliography (available on the web), and titles are submitted to the Cold Regions Bibliography Project (www.coldregions.org/).

a. Publications since your last Antarctic season

Dunbar, G.B.; Bertler, N.A.N.; McKay, R.M. 2009 Sediment flux through the McMurdo Ice Shelf in Windless Bight, Antarctica. Global and planetary change, 69(3): 87-93; doi:10.1016/j.gloplacha.2009.05.007

Mayewski, P.A.; Meredith, M.P.; Summerhayes, C.P.; Turner, J.; Worby, A.; Barrett, P.J.; Casassa, G.; Bertler, N.A.N.; Bracegirdle, T.; Naveira Garabato, A.C.; Bromwich, D.; Campbell, H.; Hamilton, G.S.; Lyons, W.B.; Maasch, K.A.; Aoki, S.; Xiao, C.; van Ommen, T. 2009 State of the Antarctic and Southern Ocean climate system. Reviews of geophysics, 47(1): RG1003, doi:10.1029/2007RG000231

Rhodes, R.H.; Bertler, N.A.N.; Baker, J.A.; Sneed, S.B.; Oerter, H.; Arrigo, K.R. 2009 Sea ice variability and primary productivity in the Ross Sea, Antarctica, from methylsulphonate snow record. Geophysical research letters, 36: L10704, doi:10.1029/2009GL037311

Arbetter, T., Arthern, R., Barbante, C., Bargagli, R., Bergstrom, D., Bertler, N.A.N., Bindschadler, R., Bockheim, J., Boutron, C., Bromwich, D., Chown, S., Clarke, A., Comiso, J., Convey, P., Cook, A., Prisco, G.d., Fahrbach, E., Jim Fastook, Andrew Fleming, Mauro Gugliemin, Julian Gutt, Hartmut Hellmer, Françoise Hennion, Karen Heywood, David Holland, Ad Huiskes, Adrian Jenkins, Anna Jones, Anthony Lenton, Dominic Hodgson, Sungmin Hong, Stan Jacobs, Katrin Linse, Gareth Marshall, Paul Mayewski, Mike Meredith, Nicolas Metzl, Andrew Monaghan, Alberto Naveira-Garabato, Steve Rintoul, Howard Roscoe, Jonathan Shanklin, Ted Scambos, Mike Sparrow, Kevin Speer, Mark Stevens, Colin Summerhayes, John Turner, Kees van der Veen, David Vaughan, Cinzia Verde, Zhaomin Wang, David Webb, Philip Woodworth, Tony Worby, Roger Worland, and Yamanouchi, T., 2009, Observations, Data Accuracy and Tools, in Turner, J., Bindschandler, R., Convey, P., di Prisco, G., Fahrbach, E., Gutt, J., Hodgson, D., Mayewski, P.A., and Summerhayes, C.P., eds., Antarctic Climate Change and the Environment: Cambridge, UK, Scientific Committee on Antarctic Research, p. 33-114, ISBN 978-0-948277-22-1

Byron Adams, Rob Arthern, Angus Atkinson, Carlo Barbante, Roberto Bargagli, Dana Bergstrom, Nancy A.N. Bertler, Robert Bindschadler, James Bockheim, Claude Boutron, David Bromwich, Steve Chown, Josifino Comiso, Pete Convey, Alison Cook, Guido di Prisco, Eberhard Fahrbach, Jim Fastook, Jaume Forcarda, Josep-Maria Gili, Mauro Gugliemin, Julian Gutt, Hartmut Hellmer, Françoise Hennion, Karen Heywood, Dominic Hodgson, David Holland, Sungmin Hong, Ad Huiskes, Enrique Isla, Stan Jacobs, Anna Jones, Andrew Lenton, Gareth Marshall, Paul Mayewski, Mike Meredith, Nicolas Metzl, Andrew Monaghan, Alberto Naveira-Garabato, Kevin Newsham, Covadonga Orejas, Lloyd Peck, Hans-Otto Pörtner, Steve Rintoul, Sharon Robinson, Howard Roscoe, Sergio Rossi, Ted Scambos, Jon Shanklin, Victor Smetacek, Kevin Speer, Mark Stevens, Colin Summerhayes, Phil Trathan, John Turner, Kees van der Veen, David Vaughan, Cinzia Verde, David Webb, Christian Wiencke, Philip Woodworth, Tony Worby, Roger Worland, and Yamanouchi, T., 2009, The Instrumental Period, in Turner, J., Bindschandler, R., Convey, P., di Prisco, G., Fahrbach, E., Gutt, J., Hodgson, D., page 5 Mayewski, P.A., and Summerhayes, C.P., eds., Antarctic Climate Change and the Environment: Cambridge, UK, Scientific Committee on Antarctic Research, p. 118-298, ISBN 978-0-948277-22-1

Nerile Abram, John Anderson, Luca Bargelloni, Peter J. Barrett, Michael J. Bentley, Nancy A.N. Bertler, Steven Chown, Andrew Clarke, Peter Convey, Alistair Crame, Xavier Crosta, Mark Curran, Guido di Prisco, Jane E. Francis, Ian Goodwin, Julian Gutt, Dominic A. Hodgson, Guillaume Massé, Valérie Masson-Delmotte, Paul A. Mayewski, Robert Mulvaney, Lloyd Peck, Hans-Otto Pörtner, Regine Röthlisberger, Mark I. Stevens, Colin P. Summerhayes, Tas van Ommen, Cinzia Verde, Elie Verleyen, Wim Vyverman, Christian Wiencke, and Zane., L., 2009, Antarctic climate and environment history in the pre-instrumental period, in Turner, J., Bindschandler, R., Convey, P., di Prisco, G., Fahrbach, E., Gutt, J., Hodgson, D., Mayewski, P.A., and Summerhayes, C.P., eds., Antarctic Climate Change and the Environment: Cambridge, UK, Scientific Committee on Antarctic Research, p. 115-182, ISBN 978-0-948277-22-1

b. Conference prese ntations since your last Antarctic season (oral or poster)

Bertler, N.A.N. 2009. The Roosevelt Island Project. WAIS Ice Core Meeting, 1st to 3rd October, La Jolla, San Diego USA

Bertler, N.A.N. 2009. Chemistry Past and Future Climate Variability in the Ross Sea Region. Annual Antarctic Conference: Sustaining the gains of the international polar year. Auckland University, Auckland New Zealand, 1-3rd July, 2009.

Bertler, N.A.N. 2009. Past Climates Symposium Lecture: Climate drivers & Ice cores. Past Climate Symposium and Australasian INTIMATE workshop. Te-Papa, Wellington, New Zealand, 15-17th May, 2009.

Bertler, N.A.N. 2009. Antarctic Climate Change. Climate of the Past – Transfer of Science to Policy, 30th January 2009, Victoria University

Bertler, N.A.N. 2009. Past and Future Climate Variability in the Ross Sea Region. Ice Core Symposium, 8th October, GNS Science, National Isotope Centre, Lower Hutt

Bull, J.R., Bertler, N.A.N., Baker, J.A., 2009. Chemistry of modern Antarctic snow: A potential ENSO indicator. Antarctica New Zealand. Annual conference: Sustaining the gains of the international polar year. Auckland University, Auckland New Zealand, 1-3rd July, 2009.

Bull, J.R., Bertler, N.A.N., Baker, J.A., 2009. Chemistry of modern Antarctic snow: A potential ENSO indicator. GNS Science, New Zealand. Past Climate Symposium and Australasian INTIMATE workshop. Te-Papa, Wellington, New Zealand, 15-17th May, 2009.

Bull, J.R., Bertler, N.A.N., Baker, J.A., 2008. Climatic controls of trace element chemistry at a coastal Antarctic site; Evans Piedmont Glacier. Joint Antarctic Research Institute (JARI). Ice core research workshop. GNS Science, Wellington, New Zealand, 15th December, 2009.

Bull, J.R., Bertler, N.A.N., Baker, J.A., 2008. Chemistry of modern Antarctic snow: A paleoenvironmental calibration for ice cores. Geological Society of New Zealand, New Zealand Geophysical Society and New Zealand Geochemical & Mineralogical Society Joint Annual Conference. Te-Papa, Wellington, New Zealand, 23-26 November, 2008. Geological Society of New Zealand Miscellaneous Publication 124A.

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Rhodes, R.H., Bertler, N.A.N., Baker, J.A., Sneed, S.B., 2008. An ice core indicator of Ross Ice Shelf stability? Joint Antarctic Research Instiute Ice Core Symposium. National Isotope Centre, GNS Science, Lower Hutt, New Zealand, 5th December, 2008.

Rhodes, R.H., Bertler, N.A.N., Baker, J.A., Sneed, S.B., 2008. An ice core indicator of Ross Ice Shelf stability? Geological Society of New Zealand, New Zealand Geophysical Society and New Zealand Geochemical & Mineralogical Society Joint Annual Conference. Te-Papa, Wellington, New Zealand, 23-26 November, 2008. Geological Society of New Zealand Miscellaneous Publication 124A.

Rhodes, R.H., Bertler, N.A.N., Baker, J.A., Sneed, S.B., 2008. An ice core indicator of Ross Ice Shelf Stability? Royal Society Beanland-Thornley Student Talks Competition. Wellington, New Zealand, 4th September 2008.

Rhodes, R.H., Bertler, N.A.N., Baker, J.A., Sneed, S.B., 2008. High resolution climate reconstruction utilizing trace element geochemistry and stable isotopes from Mt. Erebus Saddle. SCAR/IASC IPY Open Science Conference, Polar Research – Arctic and Antarctic Perspectives in the International Polar Year. St. Petersburg, Russia, 8-11th July 2008.

Rhodes, R., Bertler, N.A.N., Baker, J., and Sneed, S. B., 2008. Effects of Large Icebergs on Sea Ice and Primary Productivity in the Ross. Annual Antarctic Conference - International Polar Year and the Next Generation. Dunedin, New Zealand.

c. Planned publications

Bull, J., Bertler, N., Baker, J. (in prep.): A paleo-wind indicator from the Southern Victoria Land coast, Antarctica using major and trace element chemistry of snow pack.

Sinclair, K., Bertler, N. (in prep.): The importance of air-mass trajectory for moisture delivery to two ice core sites in the Ross Sea region, Antarctica.

d. Other outputs (MSc or PhD theses)

Bull, J.R. 2009: Stable isotope, major and trace element chemistry of modern snow from Evans Piedmont Glacier, Antarctica: insights into potential source regions and relationship of glaciochemistry to atmospheric circulation and vigour. M.Sc., Victoria University of Wellington.

Schuck, I. 2009: Mineralogical characterisation and geographic province of atmospheric particles in coastal Antarctic ice cores – indicator of past climate variability. M.Sc., University of Karlsruhe, Germany, University of Wellington, New Zealand, and GNS Science, New Zealand

4. Acknowledgements

Include persons or organisations who have assisted or funded your science programme.

I would like to thank Antarctica New Zealand staff based in Christchurch and at Scott Base. We are grateful to Margaret Auger, Tom Arnold, and Al Moore for assistance with our field work. I'm indebted for excellent and safe support by Helicopter NZ staff, in particular Rob McPhail. I'm indebted to Dr. Tim Haskell for hosting Holly Winton in the K131 event. Furthermore, we would like to thank; Ana Aguilar-Islas for the collection of 10 samples from Granite Harbour; and Pat Langhorn, Alex Gough, Wendy Claveno, James Pinchin, Keliegh Jones for their support on Holly's traverses.

I would like to thank the National Isotope Centre, GNS Science, Mr. Andy Phillips, the Geochemical Laboratory, Victoria University, Prof. Joel Baker, and the Climate Change Institute, University of Maine, Prof. Paul Mayewski for ice core analyses. This project is funded by Victoria University of Wellington, GNS Science, and Foundation for Research, Science, and Technology (Grant No. VICX0704 and CO5X0202).