Hannah Clark

Contact

Email: clarkhann4@myvuw.ac.nz
Office: CO505

Qualifications

BSc Te Herenga Waka/Victoria University Wellington (2024)

MSc thesis

Working Title

Antarctic Ice Sheet Initiation: A New Biomarker Record of Climate and Vegetation Across the Eocene-
Oligocene Transition

Supervisors

• Dr Bella Duncan
• Prof. Rob McKay

Project objectives and description

Continental-scale glaciation of Antarctica initiated during the Eocene-Oligocene Transition (EOT; 34.5–33.7Ma), suggested by climate models to have been driven by the crossing of a critical atmospheric CO₂ (pCO₂) threshold. This “tipping point” response raises concerns about, inversely, potential ice sheet destabilisation as anthropogenic pCO₂ rises.

I aim to assess the East Antarctic vegetative and hydrological response to the Eocene-Oligocene initiation of the Antarctic Ice Sheets, and identify the relative timing of onshore versus offshore environmental change. To do this, I am extracting a new biomarker-based record from the CIROS-1 sediment drillcore; biomarkers, also known as molecular fossils, are the chemical remnants of life on Earth, and sensitively record a range of environmental information such as air and ocean temperatures, hydrology, and vegetation change. I will combine this new record with other environmental proxy data from the same core to assess spatiotemporal variation in Antarctic conditions.

My research will fill a critical gap in the understanding of EOT Antarctic ice sheet initiation, and the associated implications for a potential future pCO₂ threshold response in Antarctica.

Publications

TBC