The course focuses on the study of the ocean and climate before the period covered by instrumental measurements (approximately 1850 to the present), which represents a very small fraction (<10^−7) of the history of our planet. Therefore, instrumental records offer an incomplete view of the time scales and patterns of change in the ocean and climate. Palaeoclimatology and palaeoceanography provide a comprehensive framework to understand temperature changes, precipitation patterns, ice-sheet evolution, and biosphere adaptation across a wide range of climate states and boundary conditions. This advances the debate on how the high levels of greenhouse gases predicted for the 21st century and beyond will affect key elements of the climate system.
Paleoclimatology and paleoceanography are fields within Earth Sciences that have significantly expanded their scope in recent decades. This partly arises from the knowledge of the natural patterns of change and variability in Earth's climate system that these disciplines contribute, contextualising future changes influenced by human activity. Another key factor is tied to the rapid development of methodological and analytical approaches, which are largely diversified and become (more) quantitative. These advancements are the result of multidisciplinary efforts involving sedimentologists, geochemists, geophysicists, biologists, (micro)paleontologists, geostatisticians, and modelers. Palaeoclimatology and palaeoceanography provide essential information for the ocean and climate communities. This is exemplified by their contribution to the reports of the Intergovernmental Panel on Climate Change (IPCC), which in the last almost two decades include chapters specifically dedicated to palaeoclimate and palaeoceanography. In the most recent report, such information is integrated into the assessment report's findings as one of the "multiple lines of evidence" to define the state of Earth's climate.
The course focuses on analyzing the pace, magnitude, and rates of changes in the ocean and climate through the geological timescale and from the instrumental record, with special emphasis on those changes taking place in the ocean. The following topics are explored, the: (i) different time scales (from 10^1 to 10^8 years) and patterns of climate change; (ii) research tools used to reconstruct the (paleo)ocean and (paleo)climate; and (iii) relationship between forcings, feedback processes, and the responses of the climate system, especially regarding temperature variations.
