Sarah Bonham
Postgraduate student
Telephone number:
+44(0) 113 34
39085
Email address: eesb@leeds.ac.uk
Room: 9.127
Sellwood Group for Palaeo-Climatology
Biography
Project details
Project title: Dynamics of the atmosphere and oceans during greenhouse climate states
Supervisors: Dr Alan Haywood, Professor Jane Francis
Start date: October 2007
Funding: NERC, case award with GETECH
Biography:
- MSc Oceanography - University of Southampton (2005-2006)
- BSc Environmental Science - Lancaster University (2001-2004), with a year abroad at the University of Colorado, Boulder, USA
Research:
Due to the increasing emissions of greenhouse gasses from anthropogenic sources, the next 100-300 years could see global mean temperatures rise to a level not seen for millions of years. General Circulation Models (GCMs), such as the Hadley Centre climate model (HadCM3), now play a significant role in attempts to predict the magnitude of this future climate change. In order to test these models and increase our understanding of the mechanisms which contribute to long term global warmth it is necessary to examine past warm intervals. The mid-Pliocene (3.3 - 3.0 ma) has been identified as potentially being similar to estimates for the late 21st Century, representing a globally warmer world in an equilibrium state (IPCC, 2007). Many of the boundary conditions in the mid-Pliocene were similar to modern with an atmospheric CO2 concentration between 360-400 ppmv. One of the most dominant modes of interannual variability is the El Nino-Southern Oscillation (ENSO). The recent shift in ENSO towards more El Nino events and a warmer mean state has increased the need for a greater understanding of the response of the Tropical Pacific to climate change. Palaeoproxy data from the equatorial Pacific have recorded a reduced east-west temperature gradient during the mid-Pliocene, suggesting a permanent El Nino-like state existed. The aim of this project is to examine the changes in ENSO characteristics and behaviour in a warmer climate using the Hadley Centre coupled climate model (HadCM3).