Search for a project

Ice sheet fluctuations in a warm world: simulating Pliocene climate and cryosphere

Dr Daniel Hill (SEE), Dr Aisling Dolan (SEE), Prof Alan Haywood (SEE)

Contact email: eardjh@leeds.ac.uk

The Pliocene, 5.33 – 2.58 million years ago (Ma), was the last time in Earth history when the climate was consistently warmer than today. However, within the Pliocene there are significant glacial periods and the Epoch culminates with the inception of the ice age cycles that typify Pleistocene climate. The transition from the M2 glacial (~3.3 Ma) into the KM3 isotope excursion (3.15 Ma) is a period of global ice loss as the Earth moved to a warmer than modern climate (McClymont et al., 2017). Due in part to its similarities to today, this period has become the focus for palaeoenvironmental reconstruction and palaeoclimate modelling, under the PlioVAR and PlioMIP phase 2 projects (McClymont et al., 2017; Haywood et al., 2016).

This project will build on the expertise at the University of Leeds in ice sheet and climate modelling of the Pliocene to simulate the ice sheets changes from the M2 to the KM3. During the timeframe of the project the new phase of the Pliocene Modelling Intercomparison Project (PlioMIP) will provide novel simulations of the mPWP (Haywood et al., 2016), which will allow for new estimates of the uncertainties in ice sheet models of the warmest periods of the Pliocene (e.g. Dolan et al., 2015a).

Figure 1 Potential Pliocene climate and ice sheet variability. Simulated temperature change from pre-industrial for the (A) M2 glacial period (Dolan et al., 2015b) and (B) the mid-Pliocene Warm Period (Haywood et al., 2013). Global ice sheet coverage used within these simulations (Dolan et al., 2015b).

The M2 must have seen significant increases in global ice volume (e.g. Figure 1) and has been characterised as a failed attempt at Northern Hemisphere Glaciation (de Schepper et al., 2013). However, it wasn’t until the end of the Pliocene, perhaps as late as MIS100 (2.52 Ma), that the Earth had fully transitioned to the Pleistocene ice ages (Shakun, 2017). The first ice ages around the Plio-Pleistocene boundary have a different character to late Pleistocene glacial maxima, with different provenance of North Atlantic ice-rafted debris (Bailey et al., 2013) and potentially a different sensitivity to changes in carbon dioxide (Shakun, 2017). This project will investigate these contrasting behaviours from an ice sheet and climate modelling perspective for the first time.

Objectives

There is significant scope for the successful candidate to tailor the objectives of this project to their own interests, skills and opportunities that arise. However, the following set of specific objectives would represent a potential outline of the project and three significant high impact outputs from the studentship.

  1. Develop methodology for simulating the transition from M2 Pliocene glacial to the KM3 interglacial and assess the magnitude and forcing of ice loss.
  2. Incorporate new climate model simulations from PlioMIP phase 2 into an ice sheet modelling framework and assess the range of ice sheets implied by these climatologies.
  3. Simulate the climate and growth of ice sheets at the initiation of Pleistocene ice ages during MIS100 and compare a range of plausible ice sheet configurations to the dataset of sea surface temperature (Shakun, 2017).

Training

The successful candidate will be trained in the use of the Hadley Centre climate model and ice sheet models. Further skills development in data analysis, visualisation and the scientific disciplines will also be provided. The PhD will be hosted in the palaeo@Leeds research group, providing access to a wealth of expertise in palaeoclimate modelling and palaeoenvironmental reconstruction. It is expected that the student will attend at least one international summer school (either Karthaus Summer School on Ice Sheets and Glaciers in the Climate System or Urbino Summer School in Paleoclimatology), as well as international scientific conferences.

Student profile

Palaeoclimate and Earth System modelling is by necessity a multi-disciplinary research area and no candidate will have existing skills in all the necessary disciplines. Suitable academic backgrounds include (but are not limited to) physical sciences, mathematics, geology, computing, geography etc.

References

Bailey, I., Hole, G.M., Foster, G.L., Wilson, P.A., Storey, C.D., Trueman, C.N. and Raymo, M.E., 2013. An alternative suggestion for the Pliocene onset of major northern hemisphere glaciation based on the geochemical provenance of North Atlantic Ocean ice-rafter debris. Quaternary Science Reviews, 75, 181-194.

De Schepper, S., Groeneveld, J., Naafs, B.D.A., van Renterghem, C., Henissen, J., Head, M.J., Louwye, S. and Fabian, K., 2013. Northern Hemisphere glaciation during the globally warm early late Pliocene. PLoS ONE, 8, e81508.

Dolan, A.M., Hunter, S.J., Hill, D.J., Haywood, A.M. et al., 2015a. Using results from the PlioMIP ensemble to investigate the Greenland Ice Sheet during the mid-Pliocene Warm Period, Climate of the Past, 11, 403-424.

Dolan, A.M., Haywood, A.M., Hunter, S.J., Tindall J.C., Dowsett H.J., Hill, D.J. and Pickering, S.J., 2015b. Modelling the enigmatic Late Pliocene Glacial Event - Marine Isotope Stage M2. Global and Planetary Change, 128, 47-60.

Haywood, A.M., Hill, D.J., Dolan, A.M. et al., 2013. Large-scale features of Pliocene climate: results from the Pliocene Model Intercomparison Project. Climate of the Past, 9, 191-209.

Haywood, A.M., Dowsett, H.J., Dolan, A.M., Rowley, D., Abe-Ouchi, A., Otto-Bliesner, B., Chandler, M.A., Hunter, S.J., Lunt, D.J., Pound, M. and Salzmann, U., 2016. The Pliocene Model Intercomparison Project (PlioMIP) Phase 2: Scientific objectives and experimental design. Climate of the Past, 12, 663-675.

McClymont, E.L., Haywood, A.M. and Rosell-Melé, A., 2017. Towards a marine synthesis of late Pliocene climate variability. Past Global Changes Magazine, 25, 117.

Shakun, J.D., 2017. Modest global-scale cooling despite extensive early Pleistocene ice sheets. Quaternary Science Reviews, 165, 25-30.

Related undergraduate subjects:

  • Atmospheric science
  • Computer science
  • Computing
  • Earth science
  • Earth system science
  • Environmental science
  • Geography
  • Geological science
  • Geology
  • Geophysics
  • Meteorology
  • Micropalaeontology
  • Natural sciences
  • Oceanography
  • Physical geography
  • Physical science
  • Physics