Alyssa Atwood
Assistant Professor, Florida State University
January 26, 2021
Data-Model Comparisons of Tropical Climate Change During the Common Era
The large-scale circulation of the tropical atmosphere is an essential component of the global climate system, regulating the transport of energy and moisture on regional to hemispheric scales. Billions of people around the globe depend on the seasonal and year-to-year variations in tropical rainfall that are driven by different components of this circulation, including the meridional Hadley circulation and the zonal Walker and monsoonal circulations. Importantly, it is highly uncertain how the tropical atmosphere and associated rainfall patterns will respond to continued anthropogenic warming trends, in part due to persistent biases in the representation of the tropical climate in state-of-the-art climate models. Paleoclimate records are an important tool with which to test the efficacy of such climate models, and in particular, the last 2,000 years (known as the Common Era) has been a major reconstruction target over the last decade due the relative abundance of data and the similarity of the Earth’s boundary conditions to our present climate. Paleoclimate reconstructions of the Common Era generally indicate a long-term cooling trend over the last millennium that was accompanied by widespread changes in tropical rainfall patterns. In this talk, I will review the evidence for these changes based on a compilation of ~70 paleo-hydroclimate records and compare the regional patterns in the reconstructions to those simulated by transient model simulations of the last millennium. While a number of robust regionally coherent patterns emerge from the proxy records, the model simulations exhibit weak forced long-term tropical rainfall changes that poorly agree with reconstructions, suggesting that either the tropical hydroclimate changes were unforced, or the models are unable to capture the forcings, feedbacks, or long-term hydroclimate responses over the last millennium. I will discuss the potential sources of the discrepancies and recommend future steps to better illuminate the mechanisms of the tropical hydroclimate changes over the last millennium.
Anne-Claire Fabre
Postdoc, Universität Zürich
February 2, 2021
How in vivo data on extant species can shed light on the paleoecology of extinct species?
The reconstruction of the palaeobiology (ecology, behaviour and lifestyle) of an extinct species is a difficult exercise. Palaeobiological reconstructions assume that the morphology of a species reflects its ecological adaptation(s). Thus, to understand the adaptive nature of the morphology of the skeleton it is essential to study the relationships between bones and muscles in living species and their relation to ecology, locomotion, or behaviour while taking into account potential effects of shared ancestry. In this presentation, I show how in vivo data on extant species can shed light on the paleoecology of extinct species using two examples:1) the study of forelimb shape in relation to locomotor performance and grasping behaviour; 2) the study of the cranium and mandible shape in relation to bite force in order to make integrative inferences on feeding behavior in extinct species of strepsirrhine primates.
Hazel Richards
PhD Student, Monash University
February 9 2021
Title TBA – Vertebrate paleontology
Weimu Xu
Postdoc, Trinity Dublin College
February 16, 2021
Title TBA – Paleobotony/Paleoclimate
Judi Sclafani
Postdoc
February 23, 2021
Title TBA – Paleoecology
Samantha Carter
Postdoc, Ohio State
March 2, 2021
