Late Glacial And Early Holocene Climatic Changes Based On A Multiproxy Lacustrine Sediment Record From Northeast Siberia

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Late Glacial and Early Holocene Climatic Changes Based on a Multiproxy Lacustrine Sediment Record from Northeast Siberia

Author :
Publisher :
ISBN 13 :
Total Pages : 36 pages
Book Rating : 4.:/5 (727 download)

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Book Synopsis Late Glacial and Early Holocene Climatic Changes Based on a Multiproxy Lacustrine Sediment Record from Northeast Siberia by :

Download or read book Late Glacial and Early Holocene Climatic Changes Based on a Multiproxy Lacustrine Sediment Record from Northeast Siberia written by and published by . This book was released on 2008 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: Palynological (species assemblage, pollen accumulation rate), geochemical (carbon to nitrogen ratios, organic carbon and biogenic silica content), and sedimentological (particle size, magnetic susceptibility) data combined with improved chronology and greater sampling resolution from a new core from Elikchan 4 Lake provide a stronger basis for defining paleoenvironmental changes than was previously possible. Persistence of herb-dominated tundra, slow expansion of Betula and Alnus shrubs, and low percentages of organic carbon and biogenic silica suggest that the Late-Glacial transition (ca. 16,000-11,000 cal. yr BP) was a period of gradual rather than abrupt vegetation and climatic change. Consistency of all Late-Glacial data indicates no Younger Dryas climatic oscillation. A dramatic peak in pollen accumulation rates (ca. 11,000-9800 cal. yr BP) suggests a possible summer temperature optimum, but finer grain-sizes, low magnetic susceptibility, and greater organic carbon and biogenic silica, while showing significant warming at ca. 11,000 cal. yr BP, offer no evidence of a Holocene thermal maximum. When compared to trends in other paleo-records, the new Elikchan data underscore the apparent spatial complexity of climatic responses in Northeast Siberia to global forcings between ca. 16,000-9000 cal. yr BP.

Reconstructing Late Pleistocene Deglaciation and Holocene Glacial Advance Using Lacustrine Sediments and 10Be Exposure Dating, Brooks Range, Arctic Alaska℗

Download Reconstructing Late Pleistocene Deglaciation and Holocene Glacial Advance Using Lacustrine Sediments and 10Be Exposure Dating, Brooks Range, Arctic Alaska℗ PDF Online Free

Author : Michael E. Badding
Publisher :
ISBN 13 :
Total Pages : 112 pages
Book Rating : 4.:/5 (823 download)

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Book Synopsis Reconstructing Late Pleistocene Deglaciation and Holocene Glacial Advance Using Lacustrine Sediments and 10Be Exposure Dating, Brooks Range, Arctic Alaska℗ by : Michael E. Badding

Download or read book Reconstructing Late Pleistocene Deglaciation and Holocene Glacial Advance Using Lacustrine Sediments and 10Be Exposure Dating, Brooks Range, Arctic Alaska℗ written by Michael E. Badding and published by . This book was released on 2012 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Arctic is among the most sensitive locations to climate change, where feedback mechanisms involving the cryosphere result in climate amplification. Because of their sensitivity to summer temperature and winter precipitation, glaciers can be used as proxies for climate change and reconstructions of past glacier fluctuations provide details about paleoclimate. Here, a chronology of late Pleistocene deglaciation and Neoglacial growth is constructed for two valleys in the north-central Brooks Range, Arctic Alaska. Cosmogenic 10Be exposure dating was used on ice-sculpted valley-bottom bedrock outcrops and boulders from Holocene moraine crests. Both valleys show evidence of retreat from the range front ~16-15 ka, and retreat into individual cirques by ~14 ka. There is no evidence for a standstill or re-advance during Late Glacial (14-11 ka) time. Neoglaciation was underway during the middle Holocene, constrained by a moraine dated to 4. 6±0. 5 ka.^Using this moraine age, and another moraine dated at 2. 7±0. 2 ka, this project confirms the accuracy of the previously established lichen growth curve to estimate moraine ages. This project also confirms that glaciers during early Neoglaciation had equal or larger extents than during the Little Ice Age (1200-1900 AD). Sediments collected from a proglacial lake downvalley of modern cirque glaciers reveal episodic sediment deposition from which it is difficult to isolate a signal of glacier advance. Comparing the lake sediment data to the moraine chronology suggests that Upper Kurupa Lake, based on the measured proxies, does not record glacial advances. Several conditions within the lake's catchment likely obscures any glacial signal. Further, more detailed measurements on the lake sediment might reveal additional clues on glacier activity.^Despite the apparent lack of recording changes in glacial length, sediment characteristics suggest a period of stable deposition since 1300 AD, possibly attributed to cooling during the Little Ice Age.

Arctic, Antarctic, and Alpine Research

Author :
Publisher :
ISBN 13 :
Total Pages : 812 pages
Book Rating : 4.F/5 ( download)

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Book Synopsis Arctic, Antarctic, and Alpine Research by :

Download or read book Arctic, Antarctic, and Alpine Research written by and published by . This book was released on 2008 with total page 812 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Second Assessment of Climate Change for the Baltic Sea Basin

Author : The BACC II Author Team
Publisher : Springer
ISBN 13 : 3319160060
Total Pages : 515 pages
Book Rating : 4.3/5 (191 download)

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Book Synopsis Second Assessment of Climate Change for the Baltic Sea Basin by : The BACC II Author Team

Download or read book Second Assessment of Climate Change for the Baltic Sea Basin written by The BACC II Author Team and published by Springer. This book was released on 2015-04-03 with total page 515 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is an update of the first BACC assessment, published in 2008. It offers new and updated scientific findings in regional climate research for the Baltic Sea basin. These include climate changes since the last glaciation (approx. 12,000 years ago), changes in the recent past (the last 200 years), climate projections up until 2100 using state-of-the-art regional climate models and an assessment of climate-change impacts on terrestrial, freshwater and marine ecosystems. There are dedicated new chapters on sea-level rise, coastal erosion and impacts on urban areas. A new set of chapters deals with possible causes of regional climate change along with the global effects of increased greenhouse gas concentrations, namely atmospheric aerosols and land-cover change. The evidence collected and presented in this book shows that the regional climate has already started to change and this is expected to continue. Projections of potential future climates show that the region will probably become considerably warmer and wetter in some parts, but dryer in others. Terrestrial and aquatic ecosystems have already shown adjustments to increased temperatures and are expected to undergo further changes in the near future. The BACC II Author Team consists of 141 scientists from 12 countries, covering various disciplines related to climate research and related impacts. BACC II is a project of the Baltic Earth research network and contributes to the World Climate Research Programme.

Polar Environments and Global Change

Author : Roger G. Barry
Publisher : Cambridge University Press
ISBN 13 : 1108423167
Total Pages : 445 pages
Book Rating : 4.1/5 (84 download)

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Book Synopsis Polar Environments and Global Change by : Roger G. Barry

Download or read book Polar Environments and Global Change written by Roger G. Barry and published by Cambridge University Press. This book was released on 2018-08-09 with total page 445 pages. Available in PDF, EPUB and Kindle. Book excerpt: Surveys atmospheric, oceanic and cryospheric processes, present and past conditions, and changes in polar environments.

Ecosystem Responses to Abrupt Climatic and Environmental Change in Southern Siberia During the Late Quaternary

Author : Poppy Rebekah Harding
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (111 download)

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Book Synopsis Ecosystem Responses to Abrupt Climatic and Environmental Change in Southern Siberia During the Late Quaternary by : Poppy Rebekah Harding

Download or read book Ecosystem Responses to Abrupt Climatic and Environmental Change in Southern Siberia During the Late Quaternary written by Poppy Rebekah Harding and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Late Glacial and Holocene Climate and Environmental Evolution in the Southern Baltic Iowlands Derived from Varved Lake Sediments

Author : Florian Ott
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (116 download)

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Book Synopsis Late Glacial and Holocene Climate and Environmental Evolution in the Southern Baltic Iowlands Derived from Varved Lake Sediments by : Florian Ott

Download or read book Late Glacial and Holocene Climate and Environmental Evolution in the Southern Baltic Iowlands Derived from Varved Lake Sediments written by Florian Ott and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Holocene climate variability is generally characterized by low frequency changes than compared to the last glaciations including the Lateglacial. However, there is vast evidence for decadal to centennial scale oscillations and millennial scale climate trends, which are within and beyond a human lifetime perception, respectively. Within the Baltic realm, a transitional zone between oceanic and continental climate influence, the impact of Holocene and Lateglacial climate and environmental change is currently partly understood. This is mainly attributed to the scarcity of well-dated and high-resolution sediment records and to the lacking continuity of already investigated archives. The aim of this doctoral thesis is to reconstruct Holocene and Late Glacial climate variability on local to (over)regional scales based on varved (annually laminated) sediments from Lake Czechowskie down to annual resolution. This project was carried out within the Virtual Institute for Integrated Climate and Landscape Evolution Analyses (ICLEA) and funded by the Helmholtz Association and the Helmholtz Climate Initiative REKLIM (Regional Climate Change). ICLEA intended to gain a better understanding of climate variability and landscape evolution processes in the Northern Central European lowlands since the last deglaciation. ...

Reconstructing Late Holocene Artctic Climate Change Using High Resolution Sediment Records from Simpson Lagoon, Alaska and the Colville River Alluvial Valley

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Author : Andrea Jo Miller Hanna
Publisher :
ISBN 13 :
Total Pages : 604 pages
Book Rating : 4.:/5 (936 download)

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Book Synopsis Reconstructing Late Holocene Artctic Climate Change Using High Resolution Sediment Records from Simpson Lagoon, Alaska and the Colville River Alluvial Valley by : Andrea Jo Miller Hanna

Download or read book Reconstructing Late Holocene Artctic Climate Change Using High Resolution Sediment Records from Simpson Lagoon, Alaska and the Colville River Alluvial Valley written by Andrea Jo Miller Hanna and published by . This book was released on 2015 with total page 604 pages. Available in PDF, EPUB and Kindle. Book excerpt: Arctic nearshore environments proximal to large rivers, like Simpson Lagoon, Alaska, potentially contain high-resolution sediment archives that can be utilized to reconstruct paleoclimate variability over the late Holocene. The ongoing, rapid environmental changes recently observed in the Arctic highlight the need for high-resolution records of pre-industrial climate change in this climatically sensitive region; such records are fundamental for understanding recent anthropogenic changes in the context of natural variability. This dissertation utilizes a suite of geochemical and sedimentological proxies in combination with age-constrained, shallow acoustic reflection data to demonstrate that these underutilized coastal sediment archives are capable of generating high-resolution paleoclimate records on par with other terrestrial climate archives (i.e. lake sediments, ice cores, tree rings) and provides the first ~1650-year long record of climate variability from the inner shelf of the Alaskan Beaufort Sea. An analysis of sedimentation patterns within Simpson Lagoon using CHIRP seismic data and radioisotope geochronology reveals that sediment infilling in Simpson Lagoon began ~3500 y BP, creating a primary depocenter with mm y−1 sediment accumulation in western Simpson Lagoon. The interbedded sediments suggest that major sediment reworking from ice processes, a common occurrence in Arctic shelf environments, does not disrupt the sediment archive contained within the lagoon. Quantitative reconstructions of surface air temperature are obtained using the brGDGT-derived MBT'/CBT paleothermometer. A comprehensive study of lagoon and river sediments and catchment soils demonstrate that brGDGTs are primarily soil-derived, and yield reconstructed temperatures consistent with instrumental summer temperature observations from Alaska's North Slope. Temperature reconstructions from Simpson Lagoon also show similarities with regional and pan-Arctic climate records over the last few millennia, with evidence of temperature departures correlative with noted climate events (i.e., Little Ice Age, Medieval Climate Anomaly). In addition, temporal variability in sediment sourcing to the lagoon, determined using a multi-proxy approach (i.e., granulometry, elemental analysis, clay mineralogy), broadly corresponds with temperature fluctuations, indicating relative increases in fluvial sediment discharge during colder intervals and decreased river discharge/increased coastal erosion during warmer periods. This paleoclimate variability may be driven by variations in solar output and/or shifts in the regional ocean-atmosphere circulation patterns (e.g., the Aleutian Low).

Ostracoda as Proxies for Quaternary Climate Change

Author :
Publisher : Newnes
ISBN 13 : 044453637X
Total Pages : 379 pages
Book Rating : 4.4/5 (445 download)

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Book Synopsis Ostracoda as Proxies for Quaternary Climate Change by :

Download or read book Ostracoda as Proxies for Quaternary Climate Change written by and published by Newnes. This book was released on 2012-12-31 with total page 379 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ostracod crustaceans, common microfossils in marine and freshwater sedimentary records, supply evidence of past climatic conditions via indicator species, transfer function and mutual climatic range approaches as well as the trace element and stable isotope geochemistry of their shells. As methods of using ostracods as Quaternary palaeoclimate proxies have developed, so too has a critical awareness of their complexities, potential and limitations. This book combines up-to-date reviews (covering previous work and summarising the state of the art) with presentations of new, cutting-edge science (data and interpretations as well as methodological developments) to form a major reference work that will constitute a durable bench-mark in the science of Ostracoda and Quaternary climate change. In-depth and focused treatment of palaeoclimate applications Provides durable benchmark and guide for all future work on ostracods Presents new, cutting-edge science

Late Pleistocene and Holocene Sediments Around South Georgia

Author : Nina-Marie Lešić
Publisher :
ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (143 download)

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Book Synopsis Late Pleistocene and Holocene Sediments Around South Georgia by : Nina-Marie Lešić

Download or read book Late Pleistocene and Holocene Sediments Around South Georgia written by Nina-Marie Lešić and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The island of South Georgia, along with a number of other smaller islands, is part of a microcontinent surrounded by oceanic crust in the Atlantic sector of the sub-Antarctic. Oceanographically, South Georgia lies within the Antarctic Circumpolar Current (ACC), the broad oceanic current system that is driven by the Southern Hemisphere Westerlies (SHW) and climatically isolates the Antarctic continent from the warmer Northern Hemisphere. Its location in the middle of the ACC and its isolation from continental influences makes South Georgia a sensitive region, where climate changes are registered earlier than on the more thermally isolated Antarctic continent. So far, however, the timing and extent of the Last Glacial Maximum on South Georgia have not been completely resolved, mostly because radiocarbon dated sediment investigations are missing. This is mainly due to the lack of marine geological studies on the continental shelf of the southern side of the island, which is climatically much harsher and therefore less accessible than the northern side. This information, however, is important to create and evaluate reliable climate and ice sheet models. This thesis, based on the investigations of sediment cores, sediment echosounder profiles and high-resolution bathymetry data, closes important knowledge gaps in the King Haakon Trough System and Drygalski Fjord System on the southern shelf of South Georgia. For the latter, the radiocarbon-dated sediments reveal an extensive ice cap before 30 ka BP during the Local Last Glacial Maximum. In the King Haakon Trough System, the bathymetric and sediment echo-graphic mapping of this thesis also reveal shelf-wide glaciation, possibly related to the last glacial period. Furthermore, this thesis investigates the subsequent deglaciation and the traces left by climate variability and its drivers within the sedimentary records in the two cross-shelf troughs. The results show that the southern shelf environments were ice-free since before the Antarctic Cold Reversal and thus exposed to currents at least since the start of the Holocene. These likely reacted to climate fluctuations of the present interglacial and, therefore, impacted trough sedimentation. Thus, this thesis does not only provide evidence for past ice-extent, which is crucial for benchmarking modelling approaches, but also gives further insight into the Holocene climate variability and sedimentary processes around South Georgia, potentially even archiving shelf-intruding behaviour of the nearby Southern Antarctic Circumpolar Current Front (SACCF) for at least the last 8 ka BP.

Thawing Permafrost

Author : J. van Huissteden
Publisher : Springer Nature
ISBN 13 : 3030313794
Total Pages : 508 pages
Book Rating : 4.0/5 (33 download)

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Book Synopsis Thawing Permafrost by : J. van Huissteden

Download or read book Thawing Permafrost written by J. van Huissteden and published by Springer Nature. This book was released on 2020-01-01 with total page 508 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a cross-disciplinary overview of permafrost and the carbon cycle by providing an introduction into the geographical distribution of permafrost, with a focus on the distribution of permafrost and its soil carbon reservoirs. The chapters explain the basic physical properties and processes of permafrost soils: ice, mineral and organic components, and how these interact with climate, vegetation and geomorphological processes. In particular, the book covers the role of the large quantities of ice in many permafrost soils which are crucial to understanding carbon cycle processes. An explanation is given on how permafrost becomes loaded with ice and carbon. Gas hydrates are also introduced. Structures and processes formed by the intense freeze-thaw action in the active layer are considered (e.g. ice wedging, cryoturbation), and the processes that occur as the permafrost thaws, (pond and lake formation, erosion). The book introduces soil carbon accumulation and decomposition mechanisms and how these are modified in a permafrost environment. A separate chapter deals with deep permafrost carbon, gas reservoirs and recently discovered methane emission phenomena from regions such as Northwest Siberia and the Siberian yedoma permafrost.

The Little Ice Age

Author : Jean M. Grove
Publisher : Routledge
ISBN 13 : 1134857462
Total Pages : 869 pages
Book Rating : 4.1/5 (348 download)

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Book Synopsis The Little Ice Age by : Jean M. Grove

Download or read book The Little Ice Age written by Jean M. Grove and published by Routledge. This book was released on 2019-04-30 with total page 869 pages. Available in PDF, EPUB and Kindle. Book excerpt: The evidence for the Little Ice Age, the most important fluctuation in global climate in historical times, is most dramatically represented by the advance of mountain glaciers in the sixteenth and seventeenth centuries and their retreat since about 1850. The effects on the landscape and the daily life of people have been particularly apparent in Norway and the Alps. This major book places an extensive body of material relating to Europe, in the form of documentary evidence of the history of the glaciers, their portrayal in paintings and maps, and measurements made by scientists and others, within a global perspective. It shows that the glacial history of mountain regions all over the world displays a similar pattern of climatic events. Furthermore, fluctuations on a comparable scale have occurred at intervals of a millennium or two throughout the last ten thousand years since the ice caps of North America and northwest Europe melted away. This is the first scholarly work devoted to the Little Ice Age, by an author whose research experience of the subject has been extensive. This book includes large numbers of maps, diagrams and photographs, many not published elsewhere, and very full bibliographies. It is a definitive work on the subject, and an excellent focus for the work of economic and social historians as well as glaciologists, climatologists, geographers, and specialists in mountain environment.

The Physical Geography of Northern Eurasia

Author : Maria Shahgedanova
Publisher :
ISBN 13 : 0198233841
Total Pages : 597 pages
Book Rating : 4.1/5 (982 download)

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Book Synopsis The Physical Geography of Northern Eurasia by : Maria Shahgedanova

Download or read book The Physical Geography of Northern Eurasia written by Maria Shahgedanova and published by . This book was released on 2003 with total page 597 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the third volume in The Oxford Regional Environments series. The series volumes are devoted to major regions of the world, each presenting a detailed and up-to-date body of scientific knowledge concerning a particular region. For most topics on the physical geography of Northern Eurasia abundant literature now exists. Most of it, however, is in Russian and other East European languages and this has significantly limited the number of potential readers. This volume seeks to familiarize, at an international level, those with an interest in this area with the most significant achievements in classical and current geographical research. The Physical Geography of Northern Eurasia covers most of the territory of the former USSR. The first section discusses the individual compenents of the physical environment. These chapters cut across regional boundaries and treate the area discussed as a whole. A regional analysis follows mainly in the context of geographical zonation, though a number of specific regions are given individual treatment. The concluding chapters discuss the effects of anthropogenic activities on the physical environment. The approach is an integrative one, tying together various aspects of the physical environments with the environmental implications of human activites. Every component of the environment is treated as a step in the development of the multi-faceted landscapes which in turn provide possibilities and limitations for cultural and economic usage.

Tentative Explanation of Late Glacial and Early Holocene Climatic Changes in North-western Europe

Author :
Publisher :
ISBN 13 :
Total Pages : 3 pages
Book Rating : 4.:/5 (917 download)

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Book Synopsis Tentative Explanation of Late Glacial and Early Holocene Climatic Changes in North-western Europe by :

Download or read book Tentative Explanation of Late Glacial and Early Holocene Climatic Changes in North-western Europe written by and published by . This book was released on 1978 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt:

The Climatic Changes of Later Geological Times

Author : Josiah Dwight Whitney
Publisher :
ISBN 13 :
Total Pages : 450 pages
Book Rating : 4.A/5 ( download)

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Book Synopsis The Climatic Changes of Later Geological Times by : Josiah Dwight Whitney

Download or read book The Climatic Changes of Later Geological Times written by Josiah Dwight Whitney and published by . This book was released on 1882 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt:

First Data on Lake Level Changes in Northeastern Siberia During the Postglacial Time

Author :
Publisher :
ISBN 13 :
Total Pages : 8 pages
Book Rating : 4.:/5 (727 download)

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Book Synopsis First Data on Lake Level Changes in Northeastern Siberia During the Postglacial Time by :

Download or read book First Data on Lake Level Changes in Northeastern Siberia During the Postglacial Time written by and published by . This book was released on 2005 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Moraines of the Tyellakh Group [1] (QIII24) preserved in river valleys of the northeastern Kolyma River basin indicate development of cirque-valley glaciers originating in the Kilgan Mountains located at the northeastern periphery of the Kolyma Ridge that separates drainage basins of the Sea of Okhotsk and Kolyma River. Moraines host lakes with a length of up to 1-5 km and a relatively small width depending on the valley bottom dimension. The study of lacustrine sediments, their bed-by-bed palynological analysis, and radiocarbon dating provided the first information on lake levels during the final glacial stage of the Late Pleistocene, as well as the Pleistocene-Holocene boundary and Holocene, for the upper reaches of the Kolyma River.

Long-term Environmental Change in Arctic and Antarctic Lakes

Author : Reinhard Pienitz
Publisher : Springer Science & Business Media
ISBN 13 : 1402021259
Total Pages : 579 pages
Book Rating : 4.4/5 (2 download)

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Book Synopsis Long-term Environmental Change in Arctic and Antarctic Lakes by : Reinhard Pienitz

Download or read book Long-term Environmental Change in Arctic and Antarctic Lakes written by Reinhard Pienitz and published by Springer Science & Business Media. This book was released on 2005-05-03 with total page 579 pages. Available in PDF, EPUB and Kindle. Book excerpt: Concerns about the effects of global climate change have focused attention on the vulnerability of circumpolar regions. This book offers a synthesis of the spectrum of techniques available for generating long-term environmental records from circumpolar lakes.