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The Paleocene-Eocene Thermal Maximum: A Perturbation of Carbon Cycle, Climate, and Biosphere with Implications for the Future
During the Paleocene-Eocene Thermal Maximum (PETM), ∼56 Mya, thousands of petagrams of carbon were released into the ocean-atmosphere system with attendant changes in the carbon cycle, climate, oceanExpand
Global patterns in leaf 13C discrimination and implications for studies of past and future climate
A 4.6‰ decline in the δ13C of atmospheric CO2 is estimated at the onset of the Paleocene-Eocene Thermal Maximum, an abrupt global warming event ∼55.8 Ma, leading to better constraints on past greenhouse-gas perturbations. Expand
Assessing the Causes of Late Pleistocene Extinctions on the Continents
Evidence now supports the idea that humans contributed to extinction on some continents, but human hunting was not solely responsible for the pattern of extinction everywhere, and suggests that the intersection of human impacts with pronounced climatic change drove the precise timing and geography of extinction in the Northern Hemisphere. Expand
Fossils and fossil climate: the case for equable continental interiors in the Eocene
There are many methods for inferring terrestrial palaeoclimates from palaeontological data, including the size and species diversity of ectothermic vertebrates, the locomotor and dental adaptationsExpand
Transient Floral Change and Rapid Global Warming at the Paleocene-Eocene Boundary
Floral response to warming and/or increased atmospheric CO2 during the PETM was comparable in rate and magnitude to that seen in postglacial floras and to the predicted effects of anthropogenic carbon release and climate change on future vegetation. Expand
Eocene continental climates and latitudinal temperature gradients
Global climate during the Mesozoic and early Cenozoic is thought to have been warmer than at present, but there is debate about winter temperatures. Paleontological data indicate mild temperaturesExpand
High Plant Diversity in Eocene South America: Evidence from Patagonia
Radioisotopic and paleomagnetic analyses indicate that the flora was deposited 52 million years ago, the time of the early Eocene climatic optimum, when tropical plant taxa and warm, equable climates reached middle latitudes of both hemispheres. Expand
History and causes of post-Laramide relief in the Rocky Mountain orogenic plateau
The Rocky Mountain orogenic plateau has the highest mean elevation and topographic relief in the contiguous United States. The mean altitude exceeds 2 km above sea level and relief increases from 30Expand
Paleobotanical evidence for near present-day levels of atmospheric Co2 during part of the tertiary.
This reconstruction indicates that CO(2) remained between 300 and 450 parts per million by volume for these intervals with the exception of a single high estimate near the Paleocene/Eocene boundary, and suggests that factors in addition to CO( 2) are required to explain these past intervals of global warmth. Expand
Magnitude of the carbon isotope excursion at the Paleocene-Eocene thermal maximum: The role of plant community change
Carbon-isotope measurements (δ 13 C) of leaf-wax n-alkanes from the Paleocene–Eocene Thermal Maximum (PETM) in the Bighorn Basin, Wyoming, reveal a negative carbon isotope excursion (CIE) of 4–5‰,Expand