School of Earth and Environment

Yvonne Smith Yvonne Smith

Postgraduate Researcher

Email address: eeyms@leeds.ac.uk
Room: 9.127b

Affiliation: Earth Surface Science Institute, Institute for Climate and Atmospheric Science

Biography

I'm a PhD student working with Prof Alan Haywood, Dr Daniel Hill and Dr Aisling Dolan of the University of Leeds and Prof Harry Dowsett of the US Geological Survey in Reston, Virginia, USA.

My project models iceberg trajectories using climate boundary conditions from the Pliocene and compares model results to ice-rafted debris evidence found in marine sediment cores of the North Atlantic and Nordic Seas. My project also looks at the uncertainties in the model using the PlioMIP ensemble models.

Qualifications

  • 2014: BSc in Physical Geography (First Class)

Edge Hill University, Ormskirk.

Dissertation: The Variation over Time of Weather Types using Lamb Classifications over the British Isles and the Correlation to the North Atlantic Oscillation, 1871 - 2013.

Memberships/Fellowships

  • 2014 - Present - Member of the International Glaciological Society
  • 2014 - Present - Member of the European Geosciences Union
  • 2015 - Present - Member of the American Geophysical Union

Research Interests

  • Northern Hemisphere Glaciation during the Late Pliocene (3.300 Ma - 3.025 Ma).
  • Pliocene Marine Isotope Stage M2 (cold period) and mid-Piacenzian Warm Period (mPWP) in terms of understanding the response of ice sheets in the northern hemisphere during a warming climate.
  • Ice-rafted debris from marine sediment cores
  • Iceberg trajectory modeling

Support duties

  • 2015 - 2016 - ArcGIS and Corel Draw Demonstrator

Project details

Project title

The Impact of Icebergs on Ocean Circulation and Climate: Past, Present and Future

Supervisors

Professor Alan Haywood, Dr Daniel Hill and Dr Aisling Dolan

Funding

This project is funded by the Leeds-York NERC DTP (Doctoral Training Partnership) 2014.

Start date

1st October 2014

Project outline

ABSTRACT: The Greenland Ice Sheet (GRIS) contains approximately 7.36m of sea level equivalent that could melt over the next 1000 years. Therefore understanding the response of the GRIS during past warm periods is fundamentally important. The Late Pliocene (LP) has similarities to the projected 21st Century climate, and there is enough available data to constrain ice sheet and iceberg modelling studies, thus making the LP a useful palaeoclimate modelling target.

Within the LP, the mid Piacenzian Warm Period (mPWP) is particularly well documented. The USGS PRISM (Pliocene Research, Interpretation & Synoptic Mapping) project focuses on the mPWP (3.26 –3.025Ma) and was chosen for the similarities to modern in paleogeography, CO2 levels and because fossil assemblages of LP foraminifera are largely composed of extant species. Data sets of PRISM are used as boundary conditions in climate models which simulate ice sheet and iceberg scenarios in warm conditions of the mid/high latitudes. In the mPWP, temperatures were 2–3°C warmer than present and CO2 level was about 405ppmv. Multi-climate and multi-ice sheet modelling studies show retreat in the GRIS to higher elevation.

However, immediately prior to the mPWP, Marine Isotope Stage M2 (3.3Ma) is a cold period in the warmer LP background. Localized evidence of ice during the M2 exists but if a larger northern hemisphere (NH) glaciation occurred, evidence has been erased. Evidence shows a drop in sea level up to 60m and CO2 at 220ppmv. Climate models show a medium/large NH ice cover is plausible at the M2. The exact extent during both warm and cold periods in the LP remains unclear.

Evidence of this extent can be seen in marine sediment cores as ice rafted debris (IRD) which helps decipher the state of the ice sheet. The distribution of mPWP North Atlantic IRD in space and time tells us about the location of iceberg-producing glaciers of the NH. Using the M2 and mPWP climate scenarios, we have modelled iceberg trajectories to see where IRD would be found in the North Atlantic under warm and cold LP conditions. These are compared with the location of IRD evidence in the North Atlantic.