Project

Discipline

cean biogeochemistry; carbon cycle

Lead
Lay summary
Anthropogenic carbon emissions force atmospheric CO2 far above the natural range of the last million years and cause rapidly progressing global warming. Nitrogen is a key factor in controlling the strength of the marine biological carbon pump and therefore marine nitrogen - carbon interactions impact atmospheric CO2 and climate. However, underlying mechanisms are still poorly understood.The marine nitrogen cycle may be altered more than any other nutrient biogeochemical cycle in response to rising pCO2, ocean acidification and climate change. Current observational-evidence suggests that marine nitrogen fixation, denitrification and carbon-to-nitrogen drawdown are increasing, while nitrification is expected to decrease in a future high-CO2 world, possibly tipping the nitrogen cycle into a new steady state.The aim of the project is to assess future interactions and feedbacks between the marine nitrogen cycle, the marine carbon cycle, and the climate. Climate scenario simulations over the industrial period and over the next centuries will be performed with a state-of-the-art carbon cycle-climate model including a dynamic marine ecosystem model. The sensitivity of the marine carbon and nitrogen cycle to pCO2-dependent nitrogen cycle processes and their influence on air-sea CO2 fluxes, atmospheric CO2 and climate change will be quantified in a self-consistent, 3-dimensional dynamical setting.The Atmospheric and Ocean Sciences Program at the Princeton University headed by Prof. Dr. Sarmiento, offers me the unique environment to successfully perform this research project and to interact and further learn from leading researchers in the field of climate change and ocean biogeochemistry.

Direct link to Lay Summary

Last update: 21.02.2013

Active participation

Number	Title	Start	Funding scheme

Anthropogenic carbon emissions force atmospheric CO2 far above the natural range of the last million years and cause rapidly progressing global warming. Nitrogen is a key factor in controlling the strength of the marine biological carbon pump and therefore marine nitrogen - carbon interactions impact atmospheric CO2 and climate. However, underlying mechanisms are still poorly understood. The marine nitrogen cycle may be altered more than any other nutrient biogeochemical cycle in response to rising pCO2, ocean acidification and climate change. Current observational-evidence suggests that marine nitrogen fixation, denitrification and carbon-to-nitrogen drawdown are increasing, while nitrification is expected to decrease in a future high-CO2 world, possibly tipping the nitrogen cycle into a new steady state. The aim of the project is to assess future interactions and feedbacks between the marine nitrogen cycle, the marine carbon cycle, and the climate. Climate scenario simulations over the industrial period and over the next centuries will be performed with a state-of-the-art carbon cycle-climate model including a dynamic marine ecosystem model. The sensitivity of the marine carbon and nitrogen cycle to pCO2-dependent nitrogen cycle processes and their influence on air-sea CO2 fluxes, atmospheric CO2 and climate change will be quantified in a self-consistent, 3-dimensional dynamical setting. The Atmospheric and Ocean Sciences Program at the Princeton University headed by Prof. Dr. Sarmiento, offers me the unique environment to successfully perform this research project and to interact and further learn from leading researchers in the field of climate change and ocean biogeochemistry.