A challenging position at the VU Earth Science Department. The Southern Hemisphere plays a crucial, yet understudied, role in global climate. Southern Hemisphere mid- to high latitude climate is dominated by the rain-bearing Southern Hemisphere Westerly winds. Changes in the intensity and position of the wind belt affect both upwelling and uptake of CO2 in the Southern Ocean, the main area on the planet where the deep ocean is connected to the atmosphere. About 40% of the global oceanic uptake of anthropogenic CO2 takes place here. Our general objective is to deepen our understanding of Holocene natural changes in climate, and particularly in the Southern Hemisphere westerlies. Therefore, we obtained a latitudinal transect of peat bogs on a series of sub-Antarctic islands (Îles Kerguelen, Îles Crozet and Île Amsterdam) covering the modern Southern Hemisphere westerly wind belt in the Indian sector of the Southern Ocean.
With your research, you make an important contribution to addressing today's societal challenges including sustainability, climate change and natural hazards. For example, a poleward shift of the SHWs during several consecutive austral winters recently caused severe drinking water shortages in Cape Town (South Africa). Understanding natural variability of the wind belt is critical for testing the reliability of model-based austral climate change projections. The data produced by this project is thus urgently needed and of high social impact.
This PhD NWO (Dutch Research Council)-funded project
Unravelling the Holocene history of the Southern Westerlies: driver of global climate and the carbon cycle.
You focus on the reconstruction of the Holocene evolution of the Southern Hemisphere westerlies from rain-fed peat bogs on Ile Amsterdam, using proxy-methods aimed at reconstructing
wind intensity,
precipitation and
temperature. In your research, you integrate the Ile Amsterdam reconstructions with existing multi-proxy peat records from Crozet (46°S) and Kerguelen (49°S) Islands. In this way, you provide a detailed reconstruction of past westerly wind belt dynamics in the Indian sector of the southern ocean.
The project does not involve fieldwork: the cores to be studied are available. You will collaborate with experts from and spend time at leading (inter)national institutes with state of the art facilities, such as the NIOZ (Royal Netherlands Institute for Sea Research), LSCE (Laboratory for Sciences of Climate and Environment), Gif-sur-Yvette, France, the Departments of Earth Science and Biological Sciences at the University of Bergen, Norway and Department of Geology, Quaternary Sciences, Lund University, Sweden.
Your duties
- reconstructing past peat water table depth using testate amoebae, palaeobotany (plant macrofossils) and stable isotope geochemistry (δD of n-alkanes)
- reconstructing past wind intensity using (exotic) pollen and the local windborne minerogenic component
- reconstructing temperature from a biomarker (brGDGTs) lipids from bacteria, abundantly present in peat deposits
- present results at conferences and in 4 peer-reviewed publications
- contribute to our teaching programme
- play a role in supervising MSc and BSc students
- finalize your work into a PhD thesis