Clay Minerals at the Paleocene–Eocene Thermal Maximum: Interpretations, Limits, and Perspectives
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Multi-Scale, Multi-Proxy Investigation of Late Holocene Tropical Cyclone Activity in the Western North Atlantic Basin
Multi-Scale, Multi-Proxy Investigation of Late Holocene Tropical Cyclone Activity in the Western North Atlantic Basin François Oliva Thesis submitted to the Faculty of Graduate and Postdoctoral Studies in partial fulfillment of the requirements for the Doctorate of Philosophy in Geography Department of Geography, Environment and Geomatics Faculty of Arts University of Ottawa Supervisors: Dr. André E. Viau Dr. Matthew C. Peros Thesis Committee: Dr. Luke Copland Dr. Denis Lacelle Dr. Michael Sawada Dr. Francine McCarthy © François Oliva, Ottawa, Canada, 2017 Abstract Paleotempestology, the study of past tropical cyclones (TCs) using geological proxy techniques, is a growing discipline that utilizes data from a broad range of sources. Most paleotempestological studies have been conducted using “established proxies”, such as grain-size analysis, loss-on-ignition, and micropaleontological indicators. More recently researchers have been applying more advanced geochemical analyses, such as X-ray fluorescence (XRF) core scanning and stable isotopic geochemistry to generate new paleotempestological records. This is presented as a four article-type thesis that investigates how changing climate conditions have impacted the frequency and paths of tropical cyclones in the western North Atlantic basin on different spatial and temporal scales. The first article (Chapter 2; Oliva et al., 2017, Prog Phys Geog) provides an in-depth and up-to- date literature review of the current state of paleotempestological studies in the western North Atlantic basin. The assumptions, strengths and limitations of paleotempestological studies are discussed. Moreover, this article discusses innovative venues for paleotempestological research that will lead to a better understanding of TC dynamics under future climate change scenarios. -
Sam White the Real Little Ice Age Between C.1300 and C.1850 A.D
Journal of Interdisciplinary History, xliv:3 (Winter, 2014), 327–352. THE REAL LITTLE ICE AGE Sam White The Real Little Ice Age Between c.1300 and c.1850 a.d. the world became, on average, slightly but signiªcantly colder. The change varied over time and space, and its causes remain un- certain. Nevertheless, this cooling constitutes a meaningful climate event, with signiªcant historical consequences. Both the cooling trend and its effects on humans appear to have been particularly Downloaded from http://direct.mit.edu/jinh/article-pdf/44/3/327/1706251/jinh_a_00574.pdf by guest on 28 September 2021 acute from the late sixteenth to the late seventeenth century in much of the Northern Hemisphere. This article explains why climatologists and historians are conªdent that these changes occurred. On close examination, the objections raised in this issue of the journal by Kelly and Ó Gráda turn out to be entirely unfounded. The proxy data for early mod- ern global cooling (such as tree rings and ice cores) are robust, and written weather descriptions and observations of physical phenom- ena (such as glacial movements and river freezings) by and large of- fer independent conªrmation. Kelly and Ó Gráda’s proposed alter- native measures of climate and climate change suffer from serious ºaws. As we review the evidence and refute their criticisms, it will become clear just how solid the case for the Little Ice Age (lia) has become. the case for the little ice age The evidence for early modern global cooling comes, ªrst and foremost, from extensive research into physical proxies, including ice cores, tree rings, corals, and speleothems (stalagmites and stalactites). -
Reduced El Niño–Southern Oscillation During the Last Glacial
RESEARCH | REPORTS PALEOCEANOGRAPHY vergent results and our newly generated data by considering geographic location, choice of fora- minifera species, and changes in thermocline – depth (see supplementary materials). Reduced El Niño Southern Oscillation ENSO variability is asymmetric (the El Niño warm phase is more extreme than the La Niña during the Last Glacial Maximum cold phase) (14), so temperature variations in the equatorial Pacific are not normally distrib- Heather L. Ford,1,2* A. Christina Ravelo,1 Pratigya J. Polissar2 uted (7, 15), and statistical tests that assume normality (e.g., standard deviation) can lead to El Niño–Southern Oscillation (ENSO) is a major source of global interannual variability, but erroneous conclusions with respect to changes its response to climate change is uncertain. Paleoclimate records from the Last Glacial in variance. Therefore, we use quantile-quantile Maximum (LGM) provide insight into ENSO behavior when global boundary conditions (Q-Q) plots—a simple, yet powerful way to vi- — (ice sheet extent, atmospheric partial pressure of CO2) were different from those today. sualize distribution data to compare the tem- In this work, we reconstruct LGM temperature variability at equatorial Pacific sites perature range and distribution recorded by two using measurements of individual planktonic foraminifera shells. A deep equatorial populations of individual foraminifera shells to thermocline altered the dynamics in the eastern equatorial cold tongue, resulting in interpret possible climate forcing mechanisms. reduced ENSO variability during the LGM compared to the Late Holocene. These results Sensitivity studies using modern hydrographic suggest that ENSO was not tied directly to the east-west temperature gradient, as data show how changes in ENSO and seasonality previously suggested. -
Exhibit Specimen List FLORIDA SUBMERGED the Cretaceous, Paleocene, and Eocene (145 to 34 Million Years Ago) PARADISE ISLAND
Exhibit Specimen List FLORIDA SUBMERGED The Cretaceous, Paleocene, and Eocene (145 to 34 million years ago) FLORIDA FORMATIONS Avon Park Formation, Dolostone from Eocene time; Citrus County, Florida; with echinoid sand dollar fossil (Periarchus lyelli); specimen from Florida Geological Survey Avon Park Formation, Limestone from Eocene time; Citrus County, Florida; with organic layers containing seagrass remains from formation in shallow marine environment; specimen from Florida Geological Survey Ocala Limestone (Upper), Limestone from Eocene time; Jackson County, Florida; with foraminifera; specimen from Florida Geological Survey Ocala Limestone (Lower), Limestone from Eocene time; Citrus County, Florida; specimens from Tanner Collection OTHER Anhydrite, Evaporite from early Cenozoic time; Unknown location, Florida; from subsurface core, showing evaporite sequence, older than Avon Park Formation; specimen from Florida Geological Survey FOSSILS Tethyan Gastropod Fossil, (Velates floridanus); In Ocala Limestone from Eocene time; Barge Canal spoil island, Levy County, Florida; specimen from Tanner Collection Echinoid Sea Biscuit Fossils, (Eupatagus antillarum); In Ocala Limestone from Eocene time; Barge Canal spoil island, Levy County, Florida; specimens from Tanner Collection Echinoid Sea Biscuit Fossils, (Eupatagus antillarum); In Ocala Limestone from Eocene time; Mouth of Withlacoochee River, Levy County, Florida; specimens from John Sacha Collection PARADISE ISLAND The Oligocene (34 to 23 million years ago) FLORIDA FORMATIONS Suwannee -
Paleogene and Neogene Time Scale of GTS 2012 Paleogene Neogene N
Paleogene and Neogene Time Scale of GTS 2012 Paleogene Neogene N. Vandenberghe 1, F.J. Hilgen 2 and R.P. Speijer 3 F.J. Hilgen 1, L.J. Lourens 2 and J.A. Van Dam 3 1. Department of Earth and Environmental Sciences, K. U. Leuven, Celestijnenlaan 200E, B - 3001 Leuven, Belgium, [email protected] 1. Department of Earth Sciences, Utrecht University, Budapestlaan 4, 3584 CD Utrecht, The Netherlands, [email protected] 2. Department of Earth Sciences, Utrecht University, Budapestlaan 4, 3584 CD Utrecht, The Netherlands, [email protected] 2. Department of Earth Sciences, Utrecht University, Budapestlaan 4, 3508 TA Utrecht, The Netherlands, [email protected] 3. Department of Earth and Environmental Sciences, K. U. Leuven, Celestijnenlaal 200E, B - 3001 Leuven, Belgium, [email protected] 3. Institut Català de Paleontologia Miquel Crusafont (ICP), Campus de la UAB, Mòdul ICP, E-08193 cerdanyola del Vallès, Spain, [email protected] Of the 9 Paleogene stages, only 3 remain to be formally defined: the Bartonian and Priabonian stages of upper Paleogene Time Scale Eocene and the Chattian (base of upper Oligocene). Larger 18 13 AGE Epoch/Age Polarity Mega- Dinoflagellate Cysts North American O C AGE -1.0 -0.5 -0.5 Of the 8 Neogene stages, only 2 remain to be formally defined: the Burdigalian and Langhian stages of lower and middle Mio- (Ma) Chron Cycles Planktonic Foraminifera Benthic Calcareous Nannofossils Radiolarians NALMA MP European Mammals ALMA SALMA 0.0 0.5 1.0 1.5 2.0 0.0 0.5 1.0 1.5 2.0 2.5 Age (Stage) (Ma) During the Paleogene, the global climate, being warm (Stage) Northwestern Europe Mammals other zones Foraminifera ELMA R T low latitude southern high latitude until the late Eocene, shows a significant cooling trend cene. -