Download or read book Using Foraminiferal Assemblages to Reconstruct Climate Change in the Northwestern Weddell Sea Antarctic Peninsula written by Anastasia Kyrmanidou and published by . This book was released on 2018 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: The overall objective of this dissertation was to investigate the benthic foraminiferal assemblage dynamics of the northwestern part of the Weddell Sea and to utilize them as oceanographic proxies. Spatial and temporal patterns of foraminiferal assemblages are correlated with other proxies in order to reconstruct and better understand Antarctic Peninsula (AP) paleoenvironmental changes, particularly those pertaining to bottom-water circulation, glacial fluctuations, and biological productivity on the eastern margin of the AP (EAP). This area in the northeast Antarctic Peninsula has experienced significant environmental change evidenced by the collapse of both Larsen-A and Larsen -B ice shelves, involving various preconditioned and sequential transitions in cryosphere and ecosystem dynamics. The first project (Chapter 3) presents an expanded foraminiferal and diatom record from Perseverance Drift, northeastern AP. Using benthic foraminifera and diatoms as paleoenvironmental proxies for paleoproductivity and sea ice conditions in the area, a record extending back to 3400 yr BP, constrained via radiocarbon dating of biogenic calcite was produced. The variability of the recor was compared with existing paleoenvironmental marine records of the AP, which recognize Holocene hypsithermal and cooling events, such as the Mid-Holocene Climatic Optimum and the Neoglacial period. Overall, Holocene climatic variability is complex, with warm and cool phasing occurring at different rates and at different times across the AP (Bentley et al., 2009). Based on the foraminiferal and diatom record of Perseverance Drift, this study recognizes two main intervals of climatic variability. The basal unit of the composite core, characterized by high abundances of Globocassidulina spp. Foraminiferal Assemblage (FA), indicates incursions of Weddell Sea Transitional Water over the drift site. This interval implies a period of 'freshening' of the water column, coinciding with an open-marine or seasonally open-marine environment during the middle-to-late Holocene Climatic Optimum. The upper unit of the composite core displays characteristics of slightly colder climatic conditions as indicated by the absence of calcareous foraminifera Globocassiulina spp. FA and the pronounced presence of agglutinated FAs that are indicative of the presence of heavy sea ice. Therefore, this interval is interpreted to represent the onset of Neoglaciation at the northeastern tip of the AP. The main objective of the second project (Chapter 4) was to understand modern trends in the foraminiferal-environmental relationship in order to be able to accurately interpret the environmental conditions represented in paleo-records from the eastern part of the AP (EAP), and more specifically the formerly ice shelf-covered Larsen A embayment. This project compared already published data reporting on modern foraminiferal assemblage distributions from the Larsen A embayment (collected in March 2000) with new data reporting on modern foraminiferal assemblage distributions (collected in March 2012) from approximately the same sampling locations that follow an inshore to offshore transect designed to serve as a spatial approximation for temporal differences in ice shelf coverage over the past several decades. Additionally, down-core (2012) samples were analyzed and compared with the modern datasets in an attempt to obtain longer-term information regarding the foraminiferal communities' status pre-collapse. The main difference within the span of 12 years separating the sampling efforts is the removal of the calcareous component from the foraminiferal dataset in stations from the inner part of the embayment, situated closer to the ice shelf edge. The down-core foraminiferal data, seem to be following the same pattern as observed in the modern datasets, therefore, providing proof of the concept that distance from the ice shelf edge, in combination with the effects of taphonomical dissolution and locally increased food availability, is a factor that can structure the benthic foraminiferal community composition in environments characterized by ice shelf collapse, such as the Larsen A embayment. The third project (Chapter 5) provides an analysis of foraminiferal assemblages collected from sediment core GC16B near the northern margin of Larsen C ice shelf. Foraminiferal analysis of samples collected from this core revealed a diverse assemblage of calcareous benthic foraminiferal taxa in the upper 20 cm of the core, with very low contribution from agglutinated forms. Owing to the very low absolute diatom abundance values that characterize the core, the high abundance of planktonic foraminiferal taxa relative to benthic foraminiferal taxa, and the dominance patterns of the benthic foraminiferal taxa, different hypothesis pertaining to the source of productivity in this sub-ice shelf environment have been employed involving the transport of advected food supply from the open Weddell Sea and the response of the foraminiferal fauna to less productive (than labile) organic matter as their food source.
Download or read book Tectonic Climatic and Cryospheric Evolution of the Antarctic Peninsula written by John B. Anderson and published by John Wiley & Sons. This book was released on 2013-05-02 with total page 379 pages. Available in PDF, EPUB and Kindle. Book excerpt: Published by the American Geophysical Union as part of the Special Publications Series. Tectonic, Climatic, and Cryospheric Evolution of the Antarctic Peninsula presents the analysis of data collected during the SHALDRIL program, which sampled the most complete Cenozoic stratigraphic section in the Antarctic Peninsula. The stratigraphic intervals sampled fill major gaps in the existing stratigraphic record in the region, which is believed to have been the last place in Antarctica to become fully glaciated and, as such, the last refugium for plants and animals living on the continent. Providing previously unpublished results from studies aimed at improving our understanding of the changes in climate, glacial setting, and fauna and flora that took place over the past 30 million years, the volume highlights include discussions of marine seismic and drill core records documenting the initial growth and expansion of an ice sheet across the northernmost Antarctic Peninsula continental shelf in the northwestern Weddell Sea. The book features: Detailed vegetation and phytoplankton evolution from greenhouse through icehouse conditions in Antarctica's last refugium Sand grain texture and micromorphology indicating ice sheet control of weathering style Exhumational history around the Drake Passage margins from thermochronology and sediment provenance Comprehensive review of the opening of the ocean passageway between Antarctica and South America and the associated regional tectonics. Tectonic, Climatic, and Cryospheric Evolution of the Antarctic Peninsula will be of interest to geologists, climatologists, and glaciologists interested in climate and cryosphere evolution and those factors that regulate it.
Download or read book Antarctic Peninsula Climate Variability written by Eugene Domack and published by American Geophysical Union. This book was released on 2003-01-10 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: Published by the American Geophysical Union as part of the Antarctic Research Series, Volume 79. The Antarctic Peninsula region represents our best natural laboratory to investigate how earth's major climate systems interact and how such systems respond to rapid regional warming. The scale of environmental changes now taking place across the region is large and their pace rapid but the subsystems involved are still small enough to observe and accurately document cause and affect mechanisms. For example, clarification of ice shelf stability via the Larsen Ice Shelf is vital to understanding the entire Antarctic Ice Sheet, its climate evolution, and its response to and control of sea level. By encompassing the broadest range of interdisciplinary studies, this volume provides the global change research and educational communities a framework in which to advance our knowledge of the causes behind regional warming, the dramatic glacial and ecological responses, and the potential uniqueness of the event within the region's paleoclimate record. The volume also serves as a vital resource for public policy and governmental funding agencies as well as a means to educate the large number of ecotourists that visit the region each austral summer.
Download or read book Antarctic Climate Evolution written by Fabio Florindo and published by Elsevier. This book was released on 2021-11-04 with total page 806 pages. Available in PDF, EPUB and Kindle. Book excerpt: Antarctic Climate Evolution, Second Edition, enhances our understanding of the history of the world’s largest ice sheet, and how it responded to and influenced climate change during the Cenozoic. It includes terrestrial and marine geology, sedimentology, glacier geophysics and ship-borne geophysics, coupled with results from numerical ice sheet and climate modeling. The book’s content largely mirrors the structure of the Past Antarctic Ice Sheets (PAIS) program (www.scar.org/science/pais), formed to investigate past changes in Antarctica by supporting multidisciplinary global research. This new edition reflects recent advances and is updated with several new chapters, including those covering marine and terrestrial life changes, ice shelves, advances in numerical modeling, and increasing coverage of rates of change. The approach of the PAIS program has led to substantial improvement in our knowledge base of past Antarctic change and our understanding of the factors that have guided its evolution. Offers an overview of Antarctic climate change, analyzing historical, present-day and future developments Provides the latest information on subjects ranging from terrestrial and marine geology to sedimentology and glacier geophysics in the context of Antarctic evolution Fully updated to include expanded coverage of rates of change, advances in numerical modeling, marine and terrestrial life changes, ice shelves, and more
Download or read book Benthic Foraminiferal Analysis from Barilari Bay Western Antarctic Peninsula Margin written by Ilona I. Matulaitis and published by . This book was released on 2013 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: The temperature record from the Antarctic Peninsula (AP) shows a warming trend 3°C greater than that of the Antarctic continent (Vaughan, et al., 2003). The LARsen Ice Shelf System, Antarctica (LARISSA) project was developed as an interdisciplinary collaboration to understand the impacts of global climate change on the ice shelf systems of the Peninsula. The 2010 LARISSA cruise to the western AP margin collected the two marine sediment cores from the mouth of Barilari Bay used for this thesis, Jumbo Piston Core (JPC) 127 and Jumbo Kasten Core (JKC) 55. The 77 sediment samples collected at 10 cm intervals were sieved at 63 microns to retain foraminiferal tests, identified to the species level. The 35 most abundant foraminifera species were grouped into five assemblages with one outlier species through Hierarchical Cluster Analysis (HCA), predominantly grouped by calcareous and agglutinated foraminifera. The Principal Component Analysis (PCA) yielded two principal components, which accounted for 81.5% of the variability within the data, correlated to the species Fursenkoina spp. and Bulimina aculeata . The base of this core was found to be nearly 8000 calibrated years before present (cal. yr. BP) through radiocarbon dating of the foraminiferal tests. The PCA results were correlated with the magnetic susceptibility down core, producing a timeline of four distinct zones in the mid- to late Holocene at the outer Barilari Bay core site. The earliest zone indicated stable cold bay waters, followed by a drastic change with the incursion of warmer Circumpolar Deep Water (CDW) onto the continental shelf. The third zone of this study illustrated a period of fluctuation between the cold bay waters and the CDW, interrupted by the Little Ice Age when the ice shelf in Barilari Bay extended to the mouth of the bay. The most recent zone depicts the past 200 years of melting ice shelves and the resulting increase in primary productivity observed in the bays of the western AP, discernable from the diatom, foraminifera, and sedimentological record. This description of the benthic foraminiferal record in outer Barilari Bay increases the understanding of the timing of events in the mid- to late Holocene and will serve as a correlation to other paleoclimate proxies from the LARISSA project.
Download or read book The Antarctic Paleoenvironment written by James P. Kennett and published by American Geophysical Union. This book was released on 1992-04-08 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt: Papers based on work presented at a conference held at the University of California, Santa Barbara, August 28-31 1991, entitled 'The Role of the Southern Ocean and Antarctica in Global Change : an Ocean Drilling Perspective.' Papers deal with paleoenvironmental data from the Antarctic, including geology, climate, fossils, sediments and the eustatic record.
Download or read book Encyclopedia of Quaternary Science written by Cary Mock and published by Newnes. This book was released on 2013-03-25 with total page 3883 pages. Available in PDF, EPUB and Kindle. Book excerpt: The second revised edition of the Encyclopedia of Quaternary Science, Four Volume Set, provides both students and professionals with an up-to-date reference work on this important and highly varied area of research. There are lots of new articles, and many of the articles that appeared in the first edition have been updated to reflect advances in knowledge since 2006, when the original articles were written. The second edition will contain about 375 articles, written by leading experts around the world. This major reference work is richly illustrated with more than 3,000 illustrations, most of them in colour. Research in the Quaternary sciences has advanced greatly in the last 10 years, especially since topics like global climate change, geologic hazards and soil erosion were put high on the political agenda. This second edition builds upon its award-winning predecessor to provide the reader assured quality along with essential updated coverage Contains 357 broad-ranging articles (4310 pages) written at a level that allows undergraduate students to understand the material, while providing active researchers with a ready reference resource for information in the field. Facilitates teaching and learning The first edition was regarded by many as the most significant single overview of Quaternary science ever, yet Editor-in-Chief, Scott Elias, has managed to surpass that in this second edition by securing even more expert reviews whilst retaining his renowned editorial consistency that enables readers to navigates seamlessly from one unfamiliar topic to the next
Download or read book CRREL Bibliography written by and published by . This book was released on 1999 with total page 550 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Anthropocene as a Geological Time Unit written by Jan Zalasiewicz and published by Cambridge University Press. This book was released on 2019-03-07 with total page 385 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reviews the evidence underpinning the Anthropocene as a geological epoch written by the Anthropocene Working Group investigating it. The book discusses ongoing changes to the Earth system within the context of deep geological time, allowing a comparison between the global transition taking place today with major transitions in Earth history.
Download or read book The Glacial World According to Wally written by Wallace S. Broecker and published by . This book was released on 1995 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Volcanism in Antarctica 200 Million Years of Subduction Rifting and Continental Break up written by J.L. Smellie and published by Geological Society of London. This book was released on 2021-06-09 with total page 802 pages. Available in PDF, EPUB and Kindle. Book excerpt: This memoir is the first to review all of Antarctica’s volcanism between 200 million years ago and the Present. The region is still volcanically active. The volume is an amalgamation of in-depth syntheses, which are presented within distinctly different tectonic settings. Each is described in terms of (1) the volcanology and eruptive palaeoenvironments; (2) petrology and origin of magma; and (3) active volcanism, including tephrochronology. Important volcanic episodes include: astonishingly voluminous mafic and felsic volcanic deposits associated with the Jurassic break-up of Gondwana; the construction and progressive demise of a major Jurassic to Present continental arc, including back-arc alkaline basalts and volcanism in a young ensialic marginal basin; Miocene to Pleistocene mafic volcanism associated with post-subduction slab-window formation; numerous Neogene alkaline volcanoes, including the massive Erebus volcano and its persistent phonolitic lava lake, that are widely distributed within and adjacent to one of the world’s major zones of lithospheric extension (the West Antarctic Rift System); and very young ultrapotassic volcanism erupted subglacially and forming a world-wide type example (Gaussberg).
Download or read book The Vegetation of Antarctica through Geological Time written by David J. Cantrill and published by Cambridge University Press. This book was released on 2012-11-22 with total page 489 pages. Available in PDF, EPUB and Kindle. Book excerpt: The fossil history of plant life in Antarctica is central to our understanding of the evolution of vegetation through geological time and also plays a key role in reconstructing past configurations of the continents and associated climatic conditions. This book provides the only detailed overview of the development of Antarctic vegetation from the Devonian period to the present day, presenting Earth scientists with valuable insights into the break up of the ancient supercontinent of Gondwana. Details of specific floras and ecosystems are provided within the context of changing geological, geographical and environmental conditions, alongside comparisons with contemporaneous and modern ecosystems. The authors demonstrate how palaeobotany contributes to our understanding of the paleoenvironmental changes in the southern hemisphere during this period of Earth history. The book is a complete and up-to-date reference for researchers and students in Antarctic paleobotany and terrestrial paleoecology.
Download or read book Antarctic Climate Evolution written by Fabio Florindo and published by Elsevier. This book was released on 2008-10-10 with total page 606 pages. Available in PDF, EPUB and Kindle. Book excerpt: Antarctic Climate Evolution is the first book dedicated to furthering knowledge on the evolution of the world’s largest ice sheet over its ~34 million year history. This volume provides the latest information on subjects ranging from terrestrial and marine geology to sedimentology and glacier geophysics. An overview of Antarctic climate change, analyzing historical, present-day and future developments Contributions from leading experts and scholars from around the world Informs and updates climate change scientists and experts in related areas of study
Download or read book The Ocean and Cryosphere in a Changing Climate written by Intergovernmental Panel on Climate Change (IPCC) and published by Cambridge University Press. This book was released on 2022-04-30 with total page 755 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Intergovernmental Panel on Climate Change (IPCC) is the leading international body for assessing the science related to climate change. It provides policymakers with regular assessments of the scientific basis of human-induced climate change, its impacts and future risks, and options for adaptation and mitigation. This IPCC Special Report on the Ocean and Cryosphere in a Changing Climate is the most comprehensive and up-to-date assessment of the observed and projected changes to the ocean and cryosphere and their associated impacts and risks, with a focus on resilience, risk management response options, and adaptation measures, considering both their potential and limitations. It brings together knowledge on physical and biogeochemical changes, the interplay with ecosystem changes, and the implications for human communities. It serves policymakers, decision makers, stakeholders, and all interested parties with unbiased, up-to-date, policy-relevant information. This title is also available as Open Access on Cambridge Core.
Download or read book Atlas of Benthic Foraminifera written by Ann Holbourn and published by John Wiley & Sons. This book was released on 2013-04-03 with total page 1115 pages. Available in PDF, EPUB and Kindle. Book excerpt: An up-to-date atlas of an important fossil and living group, with the Natural History Museum. Deep-sea benthic foraminifera have played a central role in biostratigraphic, paleoecological, and paleoceanographical research for over a century. These single–celled marine protists are important because of their geographic ubiquity, distinction morphologies and rapid evolutionary rates, their abundance and diversity deep–sea sediments, and because of their utility as indicators of environmental conditions both at and below the sediment–water interface. In addition, stable isotopic data obtained from deep–sea benthic foraminiferal tests provide paleoceanographers with environmental information that is proving to be of major significance in studies of global climatic change. This work collects together, for the first time, new morphological descriptions, taxonomic placements, stratigraphic occurrence data, geographical distribution summaries, and palaeoecological information, along with state-of-the-art colour photomicrographs (most taken in reflected light, just as you would see them using light microscopy), of 300 common deep-sea benthic foraminifera species spanning the interval from Jurassic - Recent. This volume is intended as a reference and research resource for post-graduate students in micropalaeontology, geological professionals (stratigraphers, paleontologists, paleoecologists, palaeoceanographers), taxonomists, and evolutionary (paleo)biologists.
Download or read book Quaternary Sea Level Changes written by Colin V. Murray-Wallace and published by Cambridge University Press. This book was released on 2014-01-30 with total page 503 pages. Available in PDF, EPUB and Kindle. Book excerpt: An important overview of Quaternary climates including detailed Pleistocene and Holocene sea-level changes, for researchers and graduate and advanced undergraduate students.
Download or read book Ocean Acidification written by National Research Council and published by National Academies Press. This book was released on 2010-09-14 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ocean has absorbed a significant portion of all human-made carbon dioxide emissions. This benefits human society by moderating the rate of climate change, but also causes unprecedented changes to ocean chemistry. Carbon dioxide taken up by the ocean decreases the pH of the water and leads to a suite of chemical changes collectively known as ocean acidification. The long term consequences of ocean acidification are not known, but are expected to result in changes to many ecosystems and the services they provide to society. Ocean Acidification: A National Strategy to Meet the Challenges of a Changing Ocean reviews the current state of knowledge, explores gaps in understanding, and identifies several key findings. Like climate change, ocean acidification is a growing global problem that will intensify with continued CO2 emissions and has the potential to change marine ecosystems and affect benefits to society. The federal government has taken positive initial steps by developing a national ocean acidification program, but more information is needed to fully understand and address the threat that ocean acidification may pose to marine ecosystems and the services they provide. In addition, a global observation network of chemical and biological sensors is needed to monitor changes in ocean conditions attributable to acidification.
