Our planet has seen some dramatic changes in climate in the past few million years. In this seminar, Dr Brierly will discuss trends in tropical sea surface temperatures and explore what these can tell us about past climate variability. He will also present findings from a multi-model study exploring the implications of a warmer climate for El Nino Southern Oscillation (ENSO).
Abstract
The past few million years have seen some dramatic changes in climate from worlds warmer the present to ones substantially colder. I will discuss the long-term trends in tropical sea surface temperatures, which has been my research focus over the past five years. I will explain why this is interesting to look at and why the Pliocene (5.2-2.6 million year ago) in general merits attention. About four million years ago, the temperature gradients in the Tropical were substantially weaker which raises some interesting questions about the climate and its variability back then. The rapid development of the east-west gradients around two million years ago even looks to have played a role spurring evolution within our own genus, Homo.
Secondly, I’m going to present some surprising findings from a multi-model ensemble about El Nino Southern Oscillation (ENSO) variability in a warm climate. The Pliocene Model Intercomparison Project (PlioMIP) saw nine global climate models perform coordinated simulations of a past world with modern, elevated carbon dioxide concentrations. It shows a weaker and less frequent ENSO in this elevated carbon dioxide with strong consistency across the models. This is in marked contrast to other palaeoclimate multi-model ensembles and to projections for the future
Biography
Chris Brierley is a lecturer in climate modelling who is interested in past climate changes. He completed his PhD at the University of Reading, where he looked at the role of ocean physics uncertainty in future climate projections. He then joined the Yale University as a their resident coupled climate modeler. Being the Geology department, meant that he naturally got interested in how the Earth’s climate has changed over the past few million years. He joined UCL Geography in 2011 to spearhead their new MSc programmes in both climate change and environmental modelling. Chris is currently spending a term-long sabbatical at the Grantham Institute.