Topics for students

A full list of topics for bachelor and master theses at the Meteorological Institute of the University of Hamburg offered by the Land Department of the MPI-Met can be found here. For below topics in the group of "Forest management in the Earth system", contact (unless otherwise noted) Julia Pongratz, Geomatikum 1719, julia.pongratz@mpimet.mpg.de.

 

BSc theses

 

How are correlations between Earth system variables affected by climate engineering?
A commonly used measure for climate change is the change in global annual mean near-surface air temperature relative to a certain reference time. One reason for the choice of this quantity as a key indicator for climate change is its correlation to other Earth system variables that societally may be more relevant. For example, regional changes in precipitation extremes have been shown to scale with global mean temperature changes. However, whether these correlations hold depends on the variable and on the temporal and spatial scales under consideration. Moreover, these relationships may break down in the case of so-called climate engineering (or geoengineering) methods. This Bachelor thesis will investigate correlations between Earth system variables in MPI-ESM (Max Planck Institute Earth System Model) scenario projections with and without climate engineering. In particular, the thesis will assess how these correlations are affected by different climate engineering methods. This information is important to develop ways of assessing climate engineering.

Contact: Sebastian Sonntag, ZMAW building room 304, sebastian.sonntag@mpimet.mpg.de.

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Effects of forest age on surface albedo
More than 60% of the world's forest has been or is managed by humans to some extent, rendering much of the forest much younger than it would naturally be. This likely has substantial influences on climate. One such influence is forest structure: it changes as forests age and determines light absorption and reflectivity (albedo) in the canopy. This Bachelor thesis will investigate if the dependence of surface albedo on forest age is detectable in observational data by combining continental-scale age reconstructions with albedo estimates from remote sensing. Such information is important for improving and evaluating global vegetation and climate models.


Literature: Pan, Yude and Chen, Jing M and Birdsey, Richard and McCullough, Kevin and He, Liming and Deng, Feng: Age structure and disturbance legacy of North American forests, Biogeosciences 8(3), 715--732, 2011

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Boiling a complex carbon cycle model down - see below under master theses.

 

 

Master theses

Boiling a complex carbon cycle model down
Earth system models (ESMs) as used in the IPCC assessments are complex representations of a large number of processes. The carbon cycle on land, for example, depends on the productivity of the plants; the transfer of different types of plant material to litter pools, wood and paper products, and soil carbon pools; and the time-scales of CO2 release from such pools by burning and respiration. However, we believe that the large number of land carbon cycle processes can be aggregated to a few key numbers that have characteristic values for each ESM. In this thesis we will develop a simple scheme for these key characteristics. We will then test the validity of this scheme by performing point-level simulations of the carbon cycle for typical vegetation transitions using the MPI-ESM. As this project is part of an international collaboration, the analysis can be extended to a wide range of other models. For a thesis at the MSc level, the findings from the point level will be linked to results from global simulations that assess CO2 emissions from land use change: How well can historical emissions from human land use activities be captured by a simple model of few key characteristics?

 

Requirements: Basic programming skills

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