Project highlights

  • Join a highly interdisciplinary, international group of researchers and modellers working on diverse aspects of climate and Earth system change in the past, present and future 
  • Develop a powerful statistical climate model to investigate key questions about past climate change, the effects of ocean bathymetry change on tectonic timescales, and its impact on the evolution of flowering plants 
  • Contribute new data and insight with potential implications for the pressing challenges of climate change and biodiversity loss.  

Overview

Climate change and climate variability are critical drivers for the evolution and extinction of species and amongst the primary determinants of the patterns of terrestrial biodiversity we see today, but the detailed patterns of climate change over evolutionary timescales are poorly known. This lack of knowledge restricts our understanding of key aspects of evolution such as the rise of the flowering plants (angiosperms) over the last 100~150 million years, through the Mesozoic and into the Cenozoic. Angiosperms are central to the ecology and biodiversity of the modern Earth system, but their rapid rise to dominance, its timing and the processes at work as plant and animal species evolved complex mutualistic collaborations, is shrouded in mystery.  

Our understanding of climate and geographical change over these timescales comes primarily from geological archives, but the detailed spatio-temporal patterns of climate variability that are critical to the species-level processes of evolution and extinction can only be obtained by computational Earth system models. On timescales of tens to hundreds of millions of years, Earth’s continental configuration changes drastically as plate tectonic processes reorganise continents and mountain ranges rise and fall, both on land and on the ocean floor, with both terrestrial topography and ocean bathymetry leading to fundamental changes in Earth’s climate. Comprehensive, process-based simulation data of ocean bathymetry on these timescales has only recently become available and the implications for climate have not yet been addressed. 

This project will create a new record of Earth’s climate evolution with unprecedented spatio-temporal detail stretching back 250 million years, covering the entire Mesozoic and Cenozoic eras. The tectonic data driving the climate simulations will come from novel simulations by project collaborator Zahirovic (Müller et al. 2019). The climate modelling will build on recently developed techniques that combine Earth system model simulation with spatio-temporal statistical approaches to reconstruct long-term climate change and shorter term variability (Holden et al. 2019, Thomson et al. 2021). Ultimately, as well as revealing the effects of changing orography and bathymetry through Earth history, the simulations will provide the basis for evolutionary modelling studies of the evolution of angiosperm biodiversity.  

Six panels show the changing arrangement of continents for the hemisphere covering Eurasia, the Arctic and Africa at 140, 120, 60, 40, 20 Ma and present time. Grey lines running along ocean basins indicate spreading ridges, flanked by lighter colours showing crustal age increasing towards the ocean margins. Darker blue colours, particularly around the Arctic in the two earliest panels, indicate extending plate regions. Darker orange and red areas, particularly between Europe and Africa, and between Asia and India, indicate compression regions. Dark lines show subduction zones, mostly encircling the continents.

Figure 1: Simulations of global tectonic development through the Cretaceous and Cenozoic, (from Müller et al. 2019) Continents are shown in grey, paleo‐age of ocean crust is shown in light colours progressing from red to green and magenta from young to old crust. Subduction zones are black lines with triangles, while mid‐ocean ridges are shown as light grey lines. Extending plate regions are indicated in light to dark blue, while plate compression regions are shown in orange/red. 

Host

The Open University

Theme

  • Climate and Environmental Sustainability
  • Organisms and Ecosystems

Supervisors

Project investigator

Co-investigators

How to apply

Methodology

A large ensemble of climate simulations will be developed with the intermediate complexity Earth system model PLASIM-GENIE (Holden et al. 2016) spanning the range of CO2, orbital and paleogeographic states relevant to the last 30 million years. Paleogeographic inputs will come from simulations carried out by collaborators in the University of SydneyThe climate simulations will be used to construct a stochastic model, or emulator, of the climate response to arbitrary input conditions, by decomposing the climate into a series of characteristic spatial patterns. The emulator will then be used to reconstruct global climate over many millions of years at very low computational cost. Modes of internal variability on shorter timescales will be incorporated into the emulator using techniques that preserve simulated climate variance. Finally, simplified representations species evolution will be used to infer potential impacts on changing patterns of biodiversity. 

Training and skills

DRs will be awarded CENTA Training Credits (CTCs) for participation in CENTA-provided and ‘free choice’ external training. One CTC can be earned per 3 hours training, and DRs must accrue 100 CTCs across the three and a half years of their PhD.  

All Faculty PhD students will be provided with extensive training opportunities through the Open University graduate school and STEM Faculty programmes including core research and outreach skills in the first year and more specifically targeted training needs at later stages. This will include training in communicating their research to a range of different audiences, through a range of channels from academic publication to social media. 

The student will also receive training in using the PLASIM-GENIE Earth system modelling framework; in statistical emulation, using Gaussian Process models; and other numerical, statistical, or data processing methods required for the project. These are likely to include: experimental design for computer experiments, Bayesian calibration, R statistical software and data visualisation.  

Partners and collaboration

Sabin Yahirovic in the University of Sydney is an expert on modelling tectonic evolution of the Earth’s crust and will collaborate on supplying paleogeographic inputs to the climate models. 

Thiago Rangel at the Federal University of Goiás in Brazil, and Oskar Hagen in Leipzig, are both experts on modelling the evolution of biodiversity, and will collaborate on estimating the potential effects of long-term climate variability on species evolution in the final stage of the project.  

Further details

For any enquiries related to this project please contact Neil Edwards, Open University, [email protected].

To apply to this project: 

  • You must include a CV with the names of at least two referees (preferably three) who can comment on your academic abilities.  

Applications must be submitted by 23:59 GMT on Wednesday 8th January 2025.  

Possible timeline

Year 1

Year 1: tasks. Setting up and running Mesozoic and Cenozoic climate model simulations and validating output projections against existing observational data and model simulations from the literature.  

Year 2

Year 2: tasks. Constructing statistical framework for spatio-temporal emulation of the climate simulations and incorporation of shorter-term variability, construction of the long-term climate model emulator. Preparation of manuscripts describing paleoclimate simulations for publication. 

Year 3

Year 3: tasks. Creating long-term climate reconstructions with the emulator and developing a simplified methodology to estimate potential effects on species evolution; presenting results at international conferences; writing up results for thesis and further publishable papers. 

Further reading

Holden, Philip B.; Edwards, Neil R.; Fraedrich, Klaus; Kirk, Edilbert; Lunkeit, Frank and Zhu, Xiuhua, (2016) PLASIM–GENIE v1.0: a new intermediate complexity AOGCM, Geoscientific Model Development, 9 pp. 3347-3361 

Holden, Philip B.; Edwards, Neil R.; Rangel, Thiago F.; Pereira, Elisa B.; Tran, Giang T. and Wilkinson, Richard D. (2019) PALEO-PGEM v1.0: a statistical emulator of Pliocene–Pleistocene climate. Geoscientific Model Development, 12(12) pp. 5137-5155. 

Müller, R.D., Zahirovic, S., Williams, S.E., Cannon, J., Seton, M., Bower, D.J., Tetley, M.G., Heine, C., Le Breton, E., Liu, S. and Russell, S.H. (2019) A global plate model including lithospheric deformation along major rifts and orogens since the Triassic. Tectonics, 38(6), pp. 1884-1907. 

Thomson, James R.; Holden, Philip B.; Anand, Pallavi; Edwards, Neil R.; Porchier, Cécile A. and Harris, Nigel B. W. (2021) Tectonic and climatic drivers of Asian monsoon evolution. Nature Communications, Article 4022(12)