This year we are advertising two PhD projects via our @NERC DTP SPITFIRE (http://www.spitfire.ac.uk/). These studentships are fully funded, but funding is allocated on a competitive basis (based on interview and application pack). See links below for details how to apply.
The ice core records of CO2 only stretch back 800 kyr. To find out how CO2 and climate are related before this we need to rely on indirect proxy methods – here we will apply the boron isotope proxy. By examining the first big glacial intervals following the intensification of northern hemisphere glaciation 2.7 million years ago, this project aims to address the following questions:
· Does the sensitivity of the climate system vary as background climate state changes?
· What is the magnitude of CO2 variability in the early Quaternary on orbital timescales? And how does this constrain the mechanisms responsible for orbital changes in CO2?
· What are the phase relationships between the major components of the climate system in the early Quaternary? What does this reveal about how the Earth System functions when warmer and colder than today?
High-resolution SST records from the last glacial cycle and the target interval for this project (Marine-isotope stage 100). Taken from Shakun (2017).
Over geological timescales the silicate weathering feedback process is thought to have kept Earths climate within habitable bounds by regulating atmospheric CO2 levels. Theory suggests that it the process of weathering of continental rocks that does this. A debate remains however regarding how much weathering is a negative feedback vs. a driver of climate change. This project aims to characterise the link between silicate weathering and climate by applying weathering tracers (e.g. d7Li, radiogenic and stable Sr-isotopes) to examining the response of weathering to rapid warming events in the past.