MSc and PhD topics

Proposals by Sönke Häseler on GHG emissions calculation in apple production

Topics that probably require strong German language skills are marked “(G)”

1) An online GHG Emissions Calculator for apple production (G)

• Develop an online application that calculates GHG emissions for apple production, requiring users (growers) to enter only readily available information.

2) Quantifying the uncertainty in calculating the GHG emissions in apple production (G)

• Estimating the carbon footprint of 1kg of apples is a highly uncertain endeavour. This is due at least to the following sources of uncertainty:
  • There are several competing GHG accounting standards for agricultural production, but none specifically for fruit production.
  • All standards are so vague as to require a good deal of interpretation / arbitrary decisions.
  • Suitable emission factors are often unavailable, and regarding those that are available, widely diverging values are equally plausible.
  • Even the activity data is often imprecise, e.g., due to yearly fluctuations in yield.
• Task: Interview a fruit farmer and calculate the carbon footprint for their apple production, incorporating all of the above sources of uncertainty. Quantify the resulting range of results and compare it to, for example, the range of results obtained in the literature for apple carbon footprints.

3) The carbon footprint of organic versus conventional/integrated apple production  (G)

• Using typical production data, ‘calculate’ the carbon footprint for two quantities of apple that are identical in all respects, except that one was grown conventionally while the other was grown organically.
• Conduct a sensitivity analysis of the result: When you vary the relevant parameters across reasonable ranges for both production types, in what percentage of the simulations does organic production perform worse than conventional production

4) The carbon footprint of different apple varieties (G)

• Based on interviews with apple growers and information from the literature, compile carbon footprints for the apple varieties that are most widely cultivated in Germany. To truly identify the impact of the varieties, take care to keep as many inputs as possible constant.
• How does the result – a recommendation regarding the most ‘climate-friendly’ apple varieties – compare to the ranking of varieties that emerges when we ask which ones are best suited to coping with the expected effects of climate change?

5) The carbon footprint of young apple trees

• Young trees raised in nurseries account for a major component of the carbon footprint of apple production. Yet despite the importance of this emission source, little is known about the carbon footprint of young apple trees, and existing studies of apple production use widely diverging values.
• Compile a carbon footprint for young apple trees, identifying its major drivers, plausible result ranges, etc.
• Data is probably best obtained from tree nurseries in the Netherlands.

6) A parsimonious GHG emissions model of apple production (G)

• Replicate the study by Foerster / Wager (2025), “A simplified LCA model to facilitate viticulture sustainability assessment”, for apple production, focusing only on GHG emissions.