Michael Ellwood's research projects include:
1) Microscopic plankton form the base of the marine food-chain and account for more than half of global primary production, and hence moderates our climate through the ocean's ability to drawdown carbon dioxide. In this project, the sources and bio-availability of the key micro-nutrient, iron, and its influence on plankton productivity in the surface ocean will be investigated by making state-of-the-art iron isotope measurements on plankton and waters samples collected from the Tasman Sea region. The knowledge generated in this project will help elucidate future impacts and feedbacks desertification of continental Australian and ocean stratification have on the supply and cycling of iron in the marine realm.
2) This research will reconstruct the distribution of nutrients in the Southern Ocean using the isotope and trace element composition of fossil marine skeletons of siliceous and carbonate organisms. Understanding the distributions of key nutrients such as phosphate, nitrate and silicate in the surface and deep ocean is essential to understand the mechanisms by which marine algae influenced the drawdown of atmospheric carbon dioxide during the past. These links between nutrients, productivity and carbon dioxide are critical to understanding future climate change and its connection to increases in atmospheric carbon dioxide concentration associated with fossil fuel burning.