Research on living plants has shown that various angiosperm leaf traits are sensitive to environmental conditions such as temperature, precipitation, atmospheric CO2 concentrations, and light level. The analysis of specific leaf physiognomic traits in fossilized leaves have displayed consistent results and can be reliably used to reconstruct paleoclimate and paleoecology. Past rapid long-term global warming events have been shown to have a distinct impact on plant communities and evaluating their response to such events could hold insight for current and future global warming. Some specific periods of interest for this study include the Paleocene-Eocene Thermal Maximum (PETM) and the Early Eocene Climatic Optimum (EECO). Many well-preserved Gulf Coastal Plain (GCP) floras from the Claiborne group in Tennessee and Kentucky have been collected for use in a systematic census collection. This project is using Digital leaf physiognomy (DiLP), Leaf Margin Analysis (LMA), and Leaf Mass per Area (Ma) to estimate mean annual temperature and mean annual precipitation. In order to obtain precise DiLP measurements, the lamina of the fossilized leaves has to be reconstructed and manipulated. The Undulation Index (waviness of leaf’s edges) will be collected and aggregated using ImageJ. Once leaf morphology is determined for each fossilized sample, patterns can be recognized about the distribution of leaf morphotypes across the three mentioned localities, and their distribution can be used to trace potential past regional microclimates. Early results have shown that several leaf morphotypes are pointing towards a warmer climate, and more open canopy framework.