Join us for our next scheduled René Salazar Speaker Series talk held by LatinX@Broad:
"Pliocene Climate in Tropical South America using Organic Geochemistry Tools"
Tuesday, February 13th, 2024
Registration required via Zoom, to register please visit: http://broad.io/LatinX_Talks
Dr. Lina C. Pérez-Angel
The Pliocene, from 5 to ~2.6 million years ago (Ma), is the last epoch when Earth’s mean temperature was ~2.5-4°C warmer than today and CO2 concentrations were approximately 400 ppm. Although Pliocene climate is well-known, there is a scarcity of Pliocene-Pleistocene records of terrestrial temperature and hydroclimatic change, particularly in the tropics, compared to marine- and mid- to high-latitude records. The Sabana de Bogotá in the Eastern Cordillera of Colombia (~4ºN) offers a unique sedimentary archive from the South American tropics, including sediment from an extinct lake preserved in the Funza-II core that dates to the late Pliocene (~4 Ma). To evaluate whether Pliocene climate in the northern tropical Andes is dominated by a thermodynamic mechanism (i.e., wet-gets-wetter) or a dynamic mechanism (e.g., El Niño-like teleconnection), we measured branched glycerol dialkyl glycerol tetraethers (brGDGTs) along with the carbon and hydrogen stable isotopic composition of sedimentary plant waxes (C31 n-alkanes) (δ13Cwax and δDwax) along the Funza-II core. Pliocene δDwax data and brGDGT-based temperature reconstructions show similar trends as those predicted from teleconnections of northern tropical Andean climate to Eastern tropical Pacific warming, as seen during major El Niño events today. These coupled Pliocene temperature and hydrology reconstructions in the Funza-II core contradict the thermodynamic “wet-gets-wetter” mechanism in this region, and further illustrate the importance of dynamical responses of the tropical Pacific Ocean to the climatology of the western Americas.
Lina is a Voss Postdoctoral Research Associate in Environment and Society at Brown University. Originally from Colombia, Lina did her Bachelor at Universidad de Los Andes and her PhD at the University of Colorado Boulder in Geological Sciences. Lina's research in paleoclimatology has contemporary relevance. During the Pliocene, between 5 and 2.5 million years ago, Earth’s atmosphere had about 400 parts per million of carbon dioxide—pretty similar to what we have now. She uses bacterial lipids and other biomarkers on rocks to see how ancient rains, droughts, and temperatures affected the environment then and compares the results to recent data to see how these processes were different from what is happening now. In addition to research, Lina is an educator and a science communicator. She is the co-founder of GeoLchat, a science communication project in Earth, Atmospheric and Planetary sciences in English and Spanish. Currently, Lina is also the Sustainability Chair of GeoLatinas Excecutive Committee, a world organization dedicated to empower Latinas in the geosciences.
Questions? Email email@example.com.