Author: Juliane MüllerPublisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
Last Glacial to Holocene Variability in the Sea Ice Distribution in Fram Strait, Arctic Gateway
Author: Juliane MüllerSea Ice
Author: David N. ThomasPublisher: John Wiley & Sons
ISBN: 1118778383
Category : Science
Languages : en
Pages : 666
Book Description
Over the past 20 years the study of the frozen Arctic and Southern Oceans and sub-arctic seas has progressed at a remarkable pace. This third edition of Sea Ice gives insight into the very latest understanding of the how sea ice is formed, how we measure (and model) its extent, the biology that lives within and associated with sea ice and the effect of climate change on its distribution. How sea ice influences the oceanography of underlying waters and the influences that sea ice has on humans living in Arctic regions are also discussed. Featuring twelve new chapters, this edition follows two previous editions (2001 and 2010), and the need for this latest update exhibits just how rapidly the science of sea ice is developing. The 27 chapters are written by a team of more than 50 of the worlds’ leading experts in their fields. These combine to make the book the most comprehensive introduction to the physics, chemistry, biology and geology of sea ice that there is. This third edition of Sea Ice will be a key resource for all policy makers, researchers and students who work with the frozen oceans and seas.
The Variability of Sea Ice in the Fram Strait Throughout Glacial-interglacial Transitions of the Late Quaternary (MIS 11 to MIS 1)
Author: Anne KremerPublisher:
ISBN:
Category : Fram Strait
Languages : en
Pages :
Book Description
Arctic Ocean, Fram Strait, sea ice, ice sheet, Quaternary, glacial-interglacial cycles, biomarkers, IP25, PIP25.
Holocene Sea-ice and Ice-sheet Variability on the Northeast Greenland Continental Shelf
Author: Nicole SyringPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Sea ice; Biomarker; Holocene; Northeast Greenland. - When will all the Arctic sea ice in summer be gone? The rapid decline in average sea-ice extent by more than one-third during the last 3 to 4 decades leaves a sad note in terms of climate model projections. Dramatic Arctic sea-ice loss generally appears faster than climate models have forecasted. Nowadays, rapidly changing environmental conditions in the Fram Strait, the passage between Greenland and Spitsbergen, are of particular concern. Sea-ice loss here is rising and the Northeast Greenland Ice Sheet is thinning. During past decades, the amount of drift ice export has increased through Fram Strait, contributing with a significant number to the freshwater budget of the Nordic seas and global ocean circulation. Here our analysis of the Northeast Greenland continental shelf located in the western Fram Strait, uniquely records past climate changes in a highly versatile environmental system of the Arctic Ocean. Multivariate analysis of molecular highly branched isoprenoids (HBIs), specific sterols, foraminifers and organic/inorganic bulk parameters were carried out on selected downcore records and surface samples from the Northeast Greenland continental shelf. These proxies allow reconstructions of past changes in sea-ice cover, primary production, terrigenous input as well as ice-sheet extent. The first manuscript provides insights into past sea-ice variability on the outer Northeast Greenland continental shelf and the seasonal formation of the Northeast Water Polynya since the onset of the Holocene to present-day. This outer shelf regime is highly influenced by drift ice and cold water from the central Arctic Ocean and annually occurring local sea-ice formation. Interactive sea-ice and ocean dynamics regulate the regional climate and biology on the marginal shelf. Continuous seasonal sea-ice presence throughout the Holocene within three prominent stages mark relatively abrupt shifts at ~9 ka and ~1 ka. A reduced to variable sea-ice cover with an overall high primary productivity most likely driven by maximum solar insolation was observed during the early Holocene. Sea-ice melt and the intensified inflow of warmer recirculating Atlantic Water favored intensive planktic blooms and fluxes of both marine and terrigenous organic matter. Environmental conditions changed towards seasonal sea-ice conditions and a stronger drift ice signal rather than local one, evidenced by terrigenous biomarkers and IRD content during the mid Holocene. Finally, a stable seasonal sea-ice margin within a fully developed polynya environment occurred during the late Holocene and highlights the last 1 ka. To understand ocean - sea ice - ice sheet interactions, a second study focuses on the inner Northeast Greenland continental shelf where marine terminating outlet glaciers of the Northeast Greenland Ice Stream are bounded by a near permanent lastfast ice barrier named Norske Øer. A downcore record that fronts the 79°Glacier embayment and includes sedimentological, micropaleontological and organic-geochemical data sets, provides fundamental insights into the detailed initial late Weichselian deglacial to Holocene sea-ice and ice sheet history. In contrast to the outer shelf, drift ice is rather trivial while the local ice barrier plays a fundamental role by preventing glaciers from calving due to the buttressing effect. A reconstruction of the waxing/waning 79°Glacier and changes in the Norske Øer ice barrier during this specific interval was generated, showing the timing of 79°Glacier retreat and disintegration, accompanied by the intensification in sea-ice conditions. Distinct lithofacies types represent the transition from deglacial conditions with a grounded 79°Glacier through a proximal to a distal glaciomarine environment displaying the onset of the 79°Glacier retreat and total disintegration of the ice shelf at 7.9 ka. Our biomarker and foraminiferal proxy records reflect local sea-ice conditions that changed from a stable sea-ice margin and high productivity system during the early Holocene Thermal Maximum (~10.6 to 9.6 ka) to prolonged seasonal sea-ice conditions in the late early Holocene (9.6 to 7.9 ka) and near perennial sea-ice conditions in the mid to late Holocene (7.9 ka to present). These changes are strongly triggered by Atlantic Water inflow decreasing from early to late Holocene times. The intrusion of warmer Atlantic Water towards the Northeast Greenland continental shelf and changes in the solar insolation supposed to be the main climate drivers. A third study addresses ways of possible diagenetic alteration on organic bulk parameters and biomarkers in recent and sub-recent samples from the Northeast Greenland continental shelf in comparison with other Arctic records. Multicorer records may be altered by near-surface degradation processes, suggested from the extremely high concentration values in the surface sediments sharply decreasing to minimum values within the uppermost about ~5 cm. Downcore records, however, predominately still reflect a primary signal. In summary ...
Arctic Sea Ice Decline
Author: Eric T. DeWeaverPublisher: John Wiley & Sons
ISBN: 1118671589
Category : Science
Languages : en
Pages : 431
Book Description
Published by the American Geophysical Union as part of the Geophysical Monograph Series, Volume 180. This volume addresses the rapid decline of Arctic sea ice, placing recent sea ice decline in the context of past observations, climate model simulations and projections, and simple models of the climate sensitivity of sea ice. Highlights of the work presented here include An appraisal of the role played by wind forcing in driving the decline; A reconstruction of Arctic sea ice conditions prior to human observations, based on proxy data from sediments; A modeling approach for assessing the impact of sea ice decline on polar bears, used as input to the U.S. Fish and Wildlife Service's decision to list the polar bear as a threatened species under the Endangered Species Act; Contrasting studies on the existence of a "tipping point," beyond which Arctic sea ice decline will become (or has already become) irreversible, including an examination of the role of the small ice cap instability in global warming simulations; A significant summertime atmospheric response to sea ice reduction in an atmospheric general circulation model, suggesting a positive feedback and the potential for short-term climate prediction. The book will be of interest to researchers attempting to understand the recent behavior of Arctic sea ice, model projections of future sea ice loss, and the consequences of sea ice loss for the natural and human systems of the Arctic.
Last Glacial Maximum to Holocene Arctic Sea-ice Variability
Author: Xiaotong XiaoArctic Climate Variability
Author: Torben KönigkPublisher: VDM Publishing
ISBN: 9783836408028
Category : Science
Languages : en
Pages : 126
Book Description
Arctic sea ice plays an important role in the global climate system due to its high reflectivity of solar radiance, isolation effects and melting- and freezing processes. Sea ice export through Fram Strait is the largest source of ice export from the Arctic into the North Atlantic Ocean. The author uses a global climate model to analyze Arctic climate variability with special focus on the Arctic sea ice export and its impact on northern hemispheric climate. The Fram Strait sea ice export shows pronounced interannual and decadal variability, which is mainly caused by variations of wind stress and sea ice thickness in Fram Strait. The physical mechanisms of these variations are investigated. Large Fram Strait sea ice export events affect oceanic and atmospheric climate conditions in the Labrador Sea one and two years later. Hence, Fram Strait sea ice export shows a high potential for predictability of climate in the Labrador Sea. This book is addressed to readers with physical and mathematical knowledge interested in Arctic climate.
Decadal to Centennial Variability of (sub-) Arctic Sea Ice Distribution and Its Paleoenvironmental Significance
Author: Henriette Marie KollingSea Ice
Author: David N. ThomasPublisher: John Wiley & Sons
ISBN: 9781444317152
Category : Technology & Engineering
Languages : en
Pages : 641
Book Description
As the Arctic perennial sea ice continues to disappear at an alarming rate, a full understanding of sea ice as a crucial global ecosystem, and the effects of its loss is vital for all those working with and studying global climate change. Building on the success of the previous edition, the second edition of Sea Ice, now much expanded and in full colour throughout, includes six completely new chapters with complete revisions of all the chapters included from the first edition. The Editors, Professor David Thomas and Dr Gerhard Dieckmann have once again drawn together an extremely impressive group of internationally respected contributing authors, ensuring a comprehensive worldwide coverage of this incredibly important topic. Sea Ice, second edition, is an essential purchase for oceanographers and marine scientists, environmental scientists, biologists, geochemists and geologists. All those involved in the study of global climate change will find this book to contain a wealth of important information. All libraries in universities and research establishments where these subjects are studied and taught will need multiple copies of this book on their shelves. truly multidisciplinary approach world leading authors and editors international in scope, covering both Arctic and Antarctic work of vital interest to all those involved in global warming and climate change research highly illustrated full colour book with colour images throughout
Seasonal to Decadal Predictions of Arctic Sea Ice
Author: National Research CouncilPublisher: National Academies Press
ISBN: 0309265266
Category : Science
Languages : en
Pages : 93
Book Description
Recent well documented reductions in the thickness and extent of Arctic sea ice cover, which can be linked to the warming climate, are affecting the global climate system and are also affecting the global economic system as marine access to the Arctic region and natural resource development increase. Satellite data show that during each of the past six summers, sea ice cover has shrunk to its smallest in three decades. The composition of the ice is also changing, now containing a higher fraction of thin first-year ice instead of thicker multi-year ice. Understanding and projecting future sea ice conditions is important to a growing number of stakeholders, including local populations, natural resource industries, fishing communities, commercial shippers, marine tourism operators, national security organizations, regulatory agencies, and the scientific research community. However, gaps in understanding the interactions between Arctic sea ice, oceans, and the atmosphere, along with an increasing rate of change in the nature and quantity of sea ice, is hampering accurate predictions. Although modeling has steadily improved, projections by every major modeling group failed to predict the record breaking drop in summer sea ice extent in September 2012. Establishing sustained communication between the user, modeling, and observation communities could help reveal gaps in understanding, help balance the needs and expectations of different stakeholders, and ensure that resources are allocated to address the most pressing sea ice data needs. Seasonal-to-Decadal Predictions of Arctic Sea Ice: Challenges and Strategies explores these topics.