The general topic of the proposal is the study of the marine carbon cycle and its role in the climate system by driving atmospheric CO2. The investigation of this interaction is vital to understanding the key feedbacks operating in the present-day Earth system.
The goal of the project is to obtain quantitative information on marine carbon cycle processes using an interdisciplinary approach. The approach proposed is to undertake a paleoclimatic study combining data from geochemical proxies in marine sediments, with results from two 3D climate models with coupled biogeochemical modules. The specific research objectives are to determine at a global scale (but with emphasis in the Southern Ocean), for some key climate time intervals, the marine export production, and fluxes of dust and iron to the oceans; the changes in surface ocean nutrient utilization; and to quantify the relative roles of certain marine carbon cycle processes to changes in atmospheric CO2 concentrations.
The main reconstruction tools are geochemical proxies, and namely biomarkers as they provide direct information on the carbon cycle, being carbon based molecules. Three time periods of interest have been selected for the study to represent i) conditions equivalent to present (Holocene); ii) a different response of the climate system to practically the same external forcing (Pliocene); and iii) extreme climatic conditions (Last Glacial Maximum). The geochemical data will be contrasted against the carbon models results to seek their validation.
The overall results will deliver new observational bounds to determine the sensitivity of the Earth’s climate to CO2, as well as the response of the carbon cycle in a warmer world, with the perspective of improving Earth system models when used in the assessment of future climates.
January 2014 to December 2016 (plus two annual renewals)
Ministerio de Economia y Competitividad - Programa Estatal de Investigación Científica y Técnica de Excelencia