Doctoral student in isotope-enabled evapotranspiration partitioning

Doctoral student in isotope-enabled evapotranspiration partitioning

This position is part of the project Isotope-enabled flux partitioning of evapotranspiration in five Swiss forest and grassland ecosystems (Iso Flux ), hosted by the groups Grassland Sciences and Wald Lab Ecohydrology . Our research focuses on the process- and system-understanding of biosphere‒atmosphere greenhouse gas exchange and its drivers in forests and grasslands, in response to management and climate, as well as on ecohydrology and stable water isotope applications.

The Grassland Sciences group is a vibrant and international working group in the Department of Environmental Systems Science, the Wald Lab Ecohydrology group is part of the Department of Civil, Environmental and Geomatic Engineering at ETH Zurich. We are looking for a reliable, enthusiastic, and highly motivated doctoral student with a passion for science to join our teams.

The position is part of the project Isotope-enabled flux partitioning of evapotranspiration (ET) in five Swiss forest and grassland ecosystems (Iso Flux) supported by an ETH Research Grant. Iso Flux investigates ecosystem water and energy fluxes as well as ecosystem resilience against climate extremes. Using continuous, high-frequency water vapor isotope measurements (δ²H, δ¹⁸O) in combination with eddy-covariance ET fluxes, we will develop more robust, less assumption-dependent methods to partition ET into evaporation (E) and transpiration (T).

Across five Swiss Flux Net sites spanning an elevational gradient, Iso Flux will (1) deploy a mobile in-situ isotope observation system, (2) quantify the water sources sustaining E and T using isotopes in precipitation, litter, and soil, and (3) compare isotope- and flux-based ET partitioning and identify drivers of ET, E, and T across seasons and years using machine learning approaches.

Both groups will provide scientific and technical support for the project.

The doctoral project focuses on assessing ET partitioning of different forest and grassland sites across Switzerland. Your work includes:

• Deployment of a mobile in-situ isotope measurement system to measure water vapor isotopes at different Swiss Flux Net sites,
• Measurement and data evaluation of eddy-covariance ET fluxes,
• Soil and plant sampling as well as water extractions to identify potential water sources,
• Assessment of different methods for ET partitioning using eddy-covariance flux and stable water isotope data, and
• Statistical analyses, including machine learning approaches.

The full-time position is funded for four years. Salary and social benefits are provided according to ETH Zurich rules.

Upon starting, you must have completed:

• A Master’s degree in atmospheric sciences, environmental sciences, forest sciences, hydrology, ecology, or a closely related science field with experience in stable water isotopes, micrometeorology, biogeochemistry, and/or plant ecophysiology.
• You must have experience with fieldwork, good statistical skills, and programming experience (e.g., in R or Python). A good standard of written and spoken English as well as a driver’s license are mandatory. Good writing skills and the ability to work in an interdisciplinary environment are expected.

• Your career with impact:
  Become part of ETH Zurich, which not only supports your professional development, but also actively contributes to positive change in society.

In line with our values , ETH Zurich encourages an inclusive culture. We promote equality of opportunity, value diversity and nurture a working and learning environment in which the rights and dignity of all our staff and students are respected. Visit our Equal Opportunities and Diversity website to find out how we ensure a fair and open environment that allows everyone to grow and flourish.

Sustainability is a core value for us – we are consistently working towards a climate-neutral future .

We look forward to receiving your online application until 1 February 2026 with the following documents:

• Letter of motivation
• CV
• Bachelor's and Master's certificates with complete transcripts
• Contact information of two…