PhD Climate reconstructions from fossil water in ancient shells

Research / Academic

This PhD position is funded through the NWO VENI grant MACRO. In this 4-year research project, you work on improving the accuracy of reconstructing climate variability in past greenhouse periods from fossil shells. The shells of mollusks (e.g. clams, mussels and oysters) are a unique archive of past climate and environmental change. During their lifetime, mollusks record short-term changes in their environment in their shells, which grow layer by layer (like tree rings). If we can decode this climate information from fossil shells that lived during periods of warm climates, we can understand the impact of global warming on short-timescale events such as seasonal changes and even weather. However, the composition of mollusk shells also depends on the composition of the seawater in which the animals live. In this project, you measure the composition of small droplets of “fossil water” which are incorporated into fossil shells. This fossil water allows us to reconstruct the composition of past oceans. With this knowledge, you make our climate reconstructions more accurate. The improved reconstructions help us further develop climate models that project the impact of future climate change on extreme seasonality and extreme weather events.

To develop this brand-new technique for analyzing fossil water measurements, you: 1. Analyze fossil water in shells from wild mollusks from different climate zones in the modern world. You study the relationship between shell and water composition and climate. 2. Grow living mollusks under controlled conditions in collaboration with the Royal Netherlands Institute for Sea Research (NIOZ). You analyze their shells to better understand how the fossil water locked in the shells relates to the composition of the seawater. 3. Apply your new knowledge about the composition of modern mollusk shells to measure and interpret the fossil water composition of fossil shells from past greenhouse periods. An important aspect of the project is applying the information gained from testing this novel method on modern mollusk shells to better interpret the data from fossil specimens. This makes this project an exciting interdisciplinary research opportunity, combining (marine) biology, geology and (inorganic) chemistry!

Your duties

  • you co-develop and independently carry out stable isotope and trace element measurements in the labs of VU
  • you manage mollusk growth experiments
  • you present your results at scientific conferences and publish your results in scientific literature
  • you contribute to teaching practicals, field- and labwork and you supervise BSc and MSc student projects (roughly 10% of your time)


  • you have a MSc degree in Earth Science, Biology, Chemistry, Environmental Science or equivalent.
  • you have affinity with (geo)chemical lab work and biological experiments working with live mollusks
  • you have previous laboratory experience and experience with programming languages (Matlab, R, Python) is an advantage
  • you are able to work independently, but you are also eager to contribute to an interdisciplinary research team
  • you have excellent writing and verbal communication skills in English

Salary Benefits:

A challenging position in a socially involved organization. The salary will be in accordance with university regulations for academic personnel and amounts €2,541 (PhD) per month during the first year and increases to €3,539 (PhD) per month during the fourth year, based on a full-time employment. The job profile: is based on the university job ranking system and is vacant for at least 1.0 FTE.

The appointment will initially be for 1 year. After a satisfactory evaluation of the initial appointment, the contract will be extended for a duration of 4 years.
Additionally, Vrije Universiteit Amsterdam offers excellent fringe benefits and various schemes and regulations to promote a good work/life balance, such as:

  • 8% holiday allowance and 8.3% end-of-year bonus
  • solid pension scheme (ABP)
  • optional model for designing a personalized benefits package
  • space for personal development
Work Hours:

38 hours per week


De Boelelaan 1105