Department of Earth Sciences
My research concerns the ocean’s role in the global carbon cycle, and in particular the complex interplay between climate, ocean circulation, and ocean biogeochemistry. Understanding and modelling these interactions is one of the fundamental challenges in science, and the key to unravelling the human impact on Earth’s climate. I use a combination of theory, simulation, and observations to addresses many different aspects of this broad theme, including: (1) using geochemical tracer observations in combination with inverse methods to quantify the uptake of anthropogenic carbon by the ocean; (2) applying mathematical tools such as Green functions in numerical models of ocean circulation to rigorously study ocean ventilation, specifically where waters (and trace gases such as carbon dioxide dissolved in them) subduct out of the surface mixed-layer, where they will subsequently resurface and be re-exposed to the atmosphere, and where and for how long they spend in between; (3) developing mechanistic parameterizations of the ocean biological pump (a major pathway by which carbon is transported from the atmosphere to the deep sea through the aggregation and subsequent sinking of phytoplankton cells) for use in large scale global climate models; and (4) developing and applying models of rare earth elements (REEs) such as neodymium, protactinium and thorium that, while poorly understood, are widely used as proxies of past ocean circulation and climate.
Associated Research Streams
anthropogenic climate change, carbon cycle, ocean dynamics, palaeoceanography, chemical oceanography, biogeochemical cycles, scientific computing, numerical methods