Climate Change and Biogeochemical Cycles

The focus of the course is on the effects of climate change on biogeochemical cycles, and on the feedbacks from biogeochemical cycles to climate. These overarching themes are adrressed in the course elements across different compartments in the Earth System, and across scales. Special attention is paid to the unmanaged terrestrial environment for two reasons: It covers the majority of the land area of the globe, and very direct interactions occur between plants, soil, and the atmosphere when compared to the aquatic environment. Terrestrial carbon, nitrogen and phosphorus cycling and the interactions between the cycles are covered. Lessons are given in radiation and energy balance, photosynthesis and respiration at leaf, plant, canopy, landscape, and biome level. Greenhouse gas (including carbon dioxide, methane and nitrous oxide) emissions and the biogeochemical processes behind the emissions, are discussed, including the impacts of these processes at the ecosystem scale and regional/global scale. Biogenic volatile organic compound emissions, the interactions with the atmosphere and feedbacks on the climate system are covered. Anthropogenic impacts on global element cycling are addressed. Biogeochemical cycling in the global ocean is particularly important for maintaining the state of the Earth System. The most important of these cycles (C, N, P, O, Si) are presented and the potential climate effects of their anthropogenic perturbation examined.

The themes of the course are:

• Studying interactions between biogeochemical cycles and climate: experiments, monitoring and modelling
• Carbon cycling in unmanaged terrestrial ecosystems, primary production
• Decomposition and methane emission
• Terrestrial nitrogen and phosphorus cycles
• Ecosystem-atmosphere interactions and feedbacks on climate
• Biogeochemical cycling in oceans
• Modelling in the Earth System