Dr Tas van Ommen
Dr Tas van Ommen: PhD, BSc(Hons), Dip. Teach.
Theme Leader: Climate Processes and Change
Principal Research Scientist: ice cores and climate
My main research interests centre around ice core palaeoclimate studies generally, and in particular, high resolution palaeoclimate work extending back into the last glacial period. Our ice core group has done much of its work on the deep, high resolution Law Dome core which extends back approximately 90 000 years. The group is also involved in obtaining century-scale records from relatively near-coastal sites that give high resolution records like Law Dome.
The focus for a lot of this work is to not only provide detailed climate reconstructions but to obtain calibrations for ice core data streams against modern meteorological data. We are interested in probing high and mid-latitude climate in the Indian Ocean and Australian sector particularly. This includes work to develop longer term climate reconstructions for the Australian region.
I am also interested, and involved through the International Partnerships in Ice Core Sciences (IPICS), in developing plans for recovering the oldest ice from the Antarctic ice sheet. As part of this interest, I am also a lead investigator in the ICECAP airborne geophysical survey work covering East Antarctica out of Casey. This work involves collaboration with ice sheet dynamics researchers to link ice sheet dynamics and ice core data, to identify potential locations where oldest ice might be located, and more generally to understand the history and evolution of the ice sheet (see related Australian Antarctic Magazine (AAM) article).
- Ice core paleoclimatology (#757)
- East Antarctic and Circum-Antarctic climate history in Queen Mary Land : An Australian contribution to ITASE (#1236)
- Aurora Basin North Ice Core Drilling 08/09: Past and Present Climate (#3025)
- High resolution studies of cosmogenic beryllium isotopes (10Be and 7Be) at Law Dome (#3064)
- ICECAP - Casey/Aurora Basin Component (#3103)
- Committee Member of the Australian Academy of Science National Committee for Earth System Science.
- SCAR Steering Committee member - Antarctica and the global climate system program.
- Secretary of the SCAR Standing Scientific Group on Physical Sciences.
- Australian representative on the International Partnerships in Ice Core Sciences (IPICS) steering committee.
- Member of the IPICS steering committees for Oldest Ice and 2000-year Array projects (aimed at constructing climate records of the last two millennia).
- Contributing author and expert reviewer for the Intergovernmental Panel on Climate Change (IPCC).
- Collaborations with groups in the United States, Denmark, Italy and France and strong links with Japan, and through IPICS, to the broader ice core community.
Key outcome areas
The ice core climate research from our group contributes to the overall work of the Antarctic Climate and Ecosystems Cooperative Research Centre (ACE CRC). The research produces data and publications which are represented in synthesis reports of the IPCC.
- ACE CRC
- Glaciology research at the Australian Antarctic Division
- Australia's contribution to Antarctic climate science (2008 report)
- Climate change: cold, hard facts on a hot topic (Australian Antarctic Magazine 9, 2005)
- Sea levels rise as Antarctic snow falls short (AAM 11, 2006)
- Is snowfall in Antarctica linked to rainfall in Australia? (AAM 13, 2007)
- Antarctic ice cores shed light on Western Australian drought (AAM 18, 2010)
van Ommen, T.D., Morgan, V. (2010) Snowfall increase in coastal East Antarctica linked with southwest Western Australian drought Nature Geoscience 3. 267-272, doi:10.1038/NGEO761; AAS Project 757
Jones, P.D., Briffa, K.R., Osborn, T.J., Lough, J.M., van Ommen, T.D. et al (2009). High-resolution palaeoclimatology of the last millennium: a review of current status and future prospects. The Holocene 19(1). 3-49; AAS Project 757
Mayewski, P.A., Meredith, M.P., Summerhayes, C.P., Turner, J., Worby, T., 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 (SASOCS). Reviews of Geophysics 47. RG1003, doi:10.1029/2007RG000231; AAS Projects 757, 2669
Schneider, D.P., Steig, E.J., van Ommen, T.D., Dixon, D.A., Mayewski, P.A. (2006). Antarctic temperatures over the past two centuries from ice cores. Geophysical Research Letters 33. L16707, doi:10.1029/2006GL027057; AAS Project 757
Monaghan, A.J., Bromwich, D.H., Fogt, R.L., Wang, S.-H., Mayewski, P.A., Dixon, D.A., Ekaykin, A., Frezzotti, M., Goodwin, I., Isaksson, E., Kaspari, D., Morgan, V.I., Oerter, H., van Ommen, T.D., Van der Veen, C.J., Wen, J. (2006). Insignificant change in Antarctic snowfall since the International Geophysical Year. Science 313. 827-831; AAS Project 757
MacFarling Meure, C., Etheridge, D., Trudinger, C., Steele, P., Langenfelds, R., van Ommen, T., Smith, A., Elkins, J. (2006). Law Dome CO2, CH4 and N2O ice core records extended to 2000 years BP. Geophysical Research Letters 33. L14810, doi:10.1029/2006GL026152; AAS Projects 124, 757
Ferretti, D.F., Miller, J.B.White, Etheridge, D.M., Lassey, K.R., Lowe, D.C., MacFarling Meure, C.M., Dreier, M.F., Trudinger, C.M., van Ommen, T.D., Langenfelds, R.L. (2005). Unexpected Changes to the Global Methane Budget over the Past 2000 Years. Science 309. 1714-1717; AAS Projects 757, 1004
van Ommen, T.D., Morgan, V., Curran, M.A.J. (2004). Deglacial and Holocene changes in accumulation at Law Dome Jacka, T.H. (ed.) Annals of Glaciology 39. 359-365; AAS Project 757
Goodwin, I.D., van Ommen, T.D., Curran, M.A.J., Mayewski, P.A. (2004). Mid latitude winter climate variability in the South Indian and south-west Pacific regions since 1300 AD. Climate Dynamics, 22(8) 22(8). 783-794, doi:10.1007/s00382-004-0403-3; AAS Project 757
Curran, M.A.J., van Ommen, T.D., Morgan, V.I., Phillips, K.L., Palmer, A.S. (2003). Ice Core Evidence for Antarctic Sea Ice Decline Since the 1950s. Science 302. 1203-1206; AAS Project 757
Morgan, V., Delmotte, M., van Ommen, T., Jouzel, J., Chappellaz, J., Woon, S., Masson-Delmotte, V., Raynaud, D. (2002). Relative Timing of Deglacial Climate Events in Antarctica and Greenland. Science 297. 1862-1864; AAS Project 757
Palmer, A.S., van Ommen, T.D., Curran, M.A.J., Morgan, V., Souney, J.M., Mayewski, P.A. (2001). High precision dating of volcanic events (A.D. 1301-1995) using ice cores from Law Dome, Antarctica. Journal of Geophysical Research 106, D22. 28,089-28,095; AAS Project 757
van Ommen, T.D., Morgan, V. (1997) Calibrating the ice core paleothermometer using seasonality. Journal of Geophysical Research 102(D8). 9351-9357; AAS Projects 757, 1168, 2132
Dr Tas van Ommen – Climate Processes and Change Theme Leader
Dr Tas van Ommen – Climate Processes and Change Theme Leader
I am a physicist by training. I started my research career as an astronomer and worked overseas for a while, came back to Australia and fell sideways into a position here at the Antarctic Division doing the physics of glaciers, so I have become a glaciologist in my career.
So the Climate Processes and Change theme covers four areas. The first of those is the ice sheet itself, the second area is the ice that floats on the ocean and oceanography all wrapped up into super sub-theme. The third area we look at is the atmosphere above Antarctica and the fourth strand to our research is looking at past climate mainly from looking at ice cores that go back in time.
Looking back in the past is really the only way you can get enough information to test your understanding of the way the climate system works. And we’ve used the really detailed ice cores that we get from Law Dome, which is near Casey station, and they’ve allowed us to look in great detail at climate change and understand it in a way that you can’t do from most ice-cores just because of this high detail.
For example we have looked at changes in snow fall in the area over the last several centuries. We’ve found quite a clear link between rainfall in Western Australia or the drought that has been there and snowfall in East Antarctica. We’ve been able to use the very long records from the ice cores to say that what we are seeing now is unusual and very likely connected to climate change itself.
One of the projects I have been involved in actually was looking with a plane that has radar under the wings, shining the radar through the ice sheet to actually get a map of the bedrock underneath. And that was fascinating because we were flying along looking at the computer traces coming back from the radar and seeing for the first time the way the bedrock had deep valleys and high mountains underneath and for the first time being able to map out large areas of Antarctica.
There are still really important questions to answer about where Antarctica and the climate system is headed. We need to understand better for example how the ice sheets are going to respond in a warming climate because any loss of the ice in the Antarctica translates to sea level rise.
One of the highlights of this career is being able to actually go into the field and do some research. Drilling for an ice core where you might be hundreds of kilometers away from the nearest other party of human beings in extreme environments, experiencing the almost sensory overload of the wind, the cold, and the stunning visual environment that you are in, it’s really invigorating.