Seminar by Roberta Hamme on Dec 2, 2015

Neon, it’s not just for signs anymore: What noble gases can tell us about ocean carbon
Roberta Hamme

Wednesday, December 2, 2015
Location: Grad House

Physical, chemical, and biological processes compete to control the carbon content of the oceans, and disentangling them in order to quantify the impact of each can be a challenge. Noble gases offer a potential window into the physics that control dissolved gases because they have no biological and few chemical influences. This talk will explore using noble gas tracers in the global ocean to constrain the physical processes that control all gases, with a focus on new data from deep-water formation areas where the bulk of ocean gas concentrations are set. High wind speeds, rapid cooling, and large swings in atmospheric pressure characterize these regions in the winter. These physical processes have competing effects on gas saturations as bubble-mediated gas exchange drives gas saturations up, cooling and low atmospheric pressure drive gas saturations down, and diffusive gas exchange drives gases toward equilibrium. The different physical properties of each of the noble gases make them more or less sensitive to these different processes, which can be developed as a useful metric for the impact of these processes on carbon in large ocean models.