Stephanie – A year in the life of a Palaeontologist – PART 2
To answer the question from my previous blog…
I created a systematic database where scientists could see all the information I found regarding the terrestrial environment, the type of vegetation that inhabited various regions, the time period these collections were dated to, and other essential information about each site that could be useful in future studies. Think of it as a Google for just the early Eocene vegetation and climate estimates. Where scientists can go look up the region or area they want to focus on and see what type of plants inhabited there and the temperature estimates calculated for that site.
After collating this information I began to see how the vegetation in the early Eocene really resembled a warmer world. Today, the Arctic and Antarctica are regions that are covered by large ice sheets and glaciers. During the early Eocene the Arctic had a diverse assemblage of trees including palms (Arecaceae) and deciduous conifers (Taxodium, Sequoia) (Suan et al., 2017). Antarctica also had evidence of a paratropical environment with mean annual temperatures reaching ~16°C and vegetation including palm trees and a high abundance of ferns (Cyatheaceae) (Pross et al., 2012).
These vegetation biome groups by Herold et al. (2014) show the difference between the modern world on the left to the early Eocene world on the right. The main difference indicates no tundra or land ice in the Eocene with a large expansion of tropical and warm-temperate forests.
I will be using all this information to reconstruct vegetative environments and estimate the temperatures these plants inhabited throughout the world. Fossils and proxies provide us tools on how to reconstruct past climates, which can help us predict what the future would look like. We don’t have a crystal ball to see into the future, so we need to look at past scenarios where the Earth was much warmer to see what our planet could potentially look like in the future. Studying the global collection of early Eocene vegetation will allow climate modelers to create a picture of the early Eocene world, helping to understanding the climate mechanisms in a high-CO2 world.
Caballero, R. and Huber, M. (2013) State-dependent climate sensitivity in past warm climates and its implications for future climate projections. Proceedings National Academy of Sciences, 110(35), 14162-14167.
Herold, N., Buzan, J., Seton, M., Goldner, A., Green, J. A. M., Müller, R. D., Markwick, P. and Huber, M. (2014) A suite of early Eocene (~ 55 Ma) climate model boundary conditions. Geoscientific Model Development, 7(5), 2077-2090.
Pross, J., Contreras, L., Bijl, P. K., Greenwood, D. R., Bohaty, S. M., Schouten, S., Bendle, J.A., Röhl, U., Tauxe, L., Raine, J.I., Huck, C. E., van de Flierdt, T., Jamieson, S.S.R., Stickley, C.E., van de Schootbrugge, B., Escutia, C., Brinkhuis, H., and Integrated Ocean Drilling Program Expedition 318 Scientists. (2012) Persistent near-tropical warmth on the Antarctic continent during the early Eocene epoch. Nature, 488(7409), 73-77.
Suan, G., Popescu, S. M., Suc, J. P., Schnyder, J., Fauquette, S., Baudin, F., Yoon, D., Piepjohn, K., Sobolev, N.N., and Labrousse, L. (2017) Subtropical climate conditions and mangrove growth in Arctic Siberia during the early Eocene. Geology, 45(6), 539-542.
West, C.K., Greenwood, D.R., and Basinger, J.F. (2015) Was the Arctic Eocene ‘rainforest’ monsoonal? Estimates of seasonal precipitation from early Eocene megafloras from Ellesmere Island, Nunavut. Earth and Planetary Science Letters, 427, 18-30.