Department of Earth and Environmental Science

Irina Marinov

The Ocean Biogeochemistry and Climate Change group

Anthropogenic global warming is expected to have a significant impact on ocean circulation, biogeochemistry, ocean pH and ecosystem structure, changes which will feedback onto the climate system and atmospheric CO2. Recent research suggests that this feedback is positive: i.e., human-induced global warming might result in a decrease in the rate at which the ocean takes up and stores atmospheric carbon dioxide, further enhancing global warming. This is clearly a worrisome trend which needs immediate investigation.

Our group’s research interests are at the frontier of ocean biogeochemistry, ocean ecology and physical oceanography. We research the oceanic controls on atmospheric pCO2 and global climate from inter-annual to millenial time scales and we wish to improve understanding and prediction of:
(a) Oceanic uptake, storage and release of atmospheric CO2 and other gases;
(b) Climate-sensitivity of ocean biogeochemical cycles and interactions with ecosystem structure; (c) Feedbacks between ocean carbon cycle, ocean ecosystem structure, ocean circulation and climate.
Our work combines theoretical aspects with running climate change simulations and sensitivity studies (using complex general circulation models or GCMs) on a newly acquired state-of-the-art computer cluster in the Earth and Environmental Science Dept. at UPenn.

Specific topics which we address are:

• How the ocean carbon pumps control atmospheric pCO2. The impact of future changes in ocean ventilation on ocean carbon pumps and atmospheric pCO2.
• Biological-physical controls on the large scale air-sea CO2 flux distributions.
• Response of Ocean Ecology to future climate change.
• How does atmospheric pCO2 respond to changes in surface nutrients, such as those associated with iron fertilization of the surface ocean?
• What is the role of oceanic mixing and circulation in determining the partition of CO2 between the atmosphere and the ocean and the global scale oceanic distribution of nutrients?
• Links between Southern Ocean winds, ocean ecology and the oceanic uptake of CO2.