Antarctic Sea Ice Variability in the Southern Ocean-Climate System PDF Download

Author: National Academies of Sciences, Engineering, and Medicine
Publisher: National Academies Press
ISBN: 0309456037
Category : Science
Languages : en
Pages : 83

View

Book Description
The sea ice surrounding Antarctica has increased in extent and concentration from the late 1970s, when satellite-based measurements began, until 2015. Although this increasing trend is modest, it is surprising given the overall warming of the global climate and the region. Indeed, climate models, which incorporate our best understanding of the processes affecting the region, generally simulate a decrease in sea ice. Moreover, sea ice in the Arctic has exhibited pronounced declines over the same period, consistent with global climate model simulations. For these reasons, the behavior of Antarctic sea ice has presented a conundrum for global climate change science. The National Academies of Sciences, Engineering, and Medicine held a workshop in January 2016, to bring together scientists with different sets of expertise and perspectives to further explore potential mechanisms driving the evolution of recent Antarctic sea ice variability and to discuss ways to advance understanding of Antarctic sea ice and its relationship to the broader ocean-climate system. This publication summarizes the presentations and discussions from the workshop.

Author: National Academies of Sciences, Engineering, and Medicine
Publisher: National Academies Press
ISBN: 0309456002
Category : Science
Languages : en
Pages : 83

View

Book Description
The sea ice surrounding Antarctica has increased in extent and concentration from the late 1970s, when satellite-based measurements began, until 2015. Although this increasing trend is modest, it is surprising given the overall warming of the global climate and the region. Indeed, climate models, which incorporate our best understanding of the processes affecting the region, generally simulate a decrease in sea ice. Moreover, sea ice in the Arctic has exhibited pronounced declines over the same period, consistent with global climate model simulations. For these reasons, the behavior of Antarctic sea ice has presented a conundrum for global climate change science. The National Academies of Sciences, Engineering, and Medicine held a workshop in January 2016, to bring together scientists with different sets of expertise and perspectives to further explore potential mechanisms driving the evolution of recent Antarctic sea ice variability and to discuss ways to advance understanding of Antarctic sea ice and its relationship to the broader ocean-climate system. This publication summarizes the presentations and discussions from the workshop.

Author: David N. Thomas
Publisher: John Wiley & Sons
ISBN: 1118778383
Category : Science
Languages : en
Pages : 666

View

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.

Author: Fabio Florindo
Publisher: Elsevier
ISBN: 0080931618
Category : Science
Languages : en
Pages : 606

View

Book Description
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

Author: Martin O. Jeffries
Publisher: American Geophysical Union
ISBN:
Category : Science
Languages : en
Pages : 416

View

Book Description
Published by the American Geophysical Union as part of the Antarctic Research Series, Volume 74. In a 1971 Scientific Committee on Antarctic Research report that reviewed polar contrasts in sea ice, Lyn Lewis and Willy Weeks made the following observation: "People who study sea ice in the Arctic Basin are commonly asked if they have ever studied ice in Antarctica, and they answer 'why bother, it's the same old stuff." Noting this was "fortunately true to a considerable extent," they added "It is clear that future work will depend critically on the logistics facilities available to allow surface observations beyond the fast ice edge at all seasons of the year. Of almost equal importance will be the development of instruments and recording equipment suited for use in the polar environment" (Lewis, E. L., and W. F. Weeks, Sea Ice: Some Polar Contrasts, in, Antarctic Ice and Water Masses, edited by G. Deacon, Scientific Committee on Antarctic Research, Cambridge, 23-34, 1971). Lewis and Weeks made no specific mention of Earth-orbiting satellites, on which the first passive microwave sensor became operational in December 1972. Less than a year later the giant Weddell Polynya was observed for the first time. Perhaps more than any other development, this unexpected feature illustrated the potential to greatly expand our knowledge of sea ice through the application of spaceborne remote sensing. Simultaneously, it acted as a catalyst for a significant increase in the level of research.

Author: Neloy Khare
Publisher: CRC Press
ISBN: 1000554597
Category : Science
Languages : en
Pages : 338

View

Book Description
This is the first book to provide a comprehensive overview of climate change–related investigations carried out by Indian researchers through initiatives in southern high latitude regions. It explains climate variability over the Southern Ocean and Antarctica; air, sea, ice, and atmosphere interactions; and the impact of climate variability on sea ice and the polar atmosphere. The data were gathered at two Indian research bases, Maitri and Bharti, which are ideal sites to study and understand climatic evolution in Antarctic in the past and recent changes. This book helps to understand climatological perspectives and to evaluate some of the most pressing issues in the south polar region. FEATURES Highlights the achievements of India in the contemporary field of Antarctic climatology Presents four decades of research by Indian scientists in Antarctica, which is now shared for the first time with the global community Includes case studies on climatological and environmental conditions of natural archives to shed light on climate scenarios in the Southern Ocean and Antarctic regions Covers various aspects of climate variability and induced air-sea-ice-atmosphere interactions This book is edited by one of the top scientists and researchers of India in the field of paleoclimatology, and the contributors are experts in the Antarctic region.

Author: Intergovernmental Panel on Climate Change (IPCC)
Publisher: Cambridge University Press
ISBN: 1009178466
Category : Science
Languages : en
Pages : 1807

View

Book Description
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.

Author: Earle Wilson
Publisher:
ISBN:
Category :
Languages : en
Pages : 106

View

Book Description
This dissertation explores key physical mechanisms that control upper ocean and sea ice variability in the Southern Ocean. The first portion of this work presents an observational analysis of wintertime upper ocean stability and pycnocline heat availability in the Antarctic sea ice zone. This analysis reveals that the southern Weddell Sea region, which features a weak upper ocean stratification and relatively strong thermocline, is preconditioned for exceptionally high rates of winter ventilation. In other open-ocean regions, such as the northern Ross Sea, the stronger winter stratification greatly limits the efficiency with which heat may be extracted from the pycnocline. The coupling between winter ice growth and upper ocean ventilation is further explored using an idealized 1D sea ice-ocean model. This model is used to simulate winter ice growth in different regions under identical surface forcing. Consistent with the observational analysis, these simulations show that the unique thermohaline structure of the Weddell Sea, specifically that near Maud Rise, facilitates a strong negative feedback to winter sea ice growth. For this region, the entrainment of heat into the mixed layer can maintain a near-constant ice thickness over much of winter. However, these simulations also reveal that this quasi-equilibrium is attained when the pycnocline is thin and supports a large vertical temperature gradient. Further experimentation demonstrates that the surface stress imparted by a powerful storm may upset this balance and lead to substantial ice melt. In simulations initialized with profiles from more strongly stratified regions, such as near the sea ice edge of the major polar gyres, the entrainment of heat into the mixed layer had weak impact on winter ice growth---even during periods of strong wind forcing. Thus, a key takeaway is that the thermodynamic coupling between winter sea ice growth and ocean ventilation has significant regional variability. This regionality must be considered when evaluating the response of the Antarctic ice-ocean system to future changes in ocean stratification and surface forcing. In the final portion of this dissertation, focus is shifted to variations in Southern Ocean sea surface temperature (SST) and sea ice extent (SIE) on seasonal timescales. This work is motivated by the abrupt reversal of Southern Ocean SST and SIE trends that occurred in 2016 and 2017. The first half of this chapter examines the role of surface winds in the initiation of the anomalous sea ice retreat that occurred in late 2016. This is done via a simple regression analysis that quantifies the linear relationship between seasonal SIC anomalies and near-instantaneous local wind anomalies, using observations and reanalysis. With this empirical relationship, we demonstrate that surface wind anomalies can largely explain the SIC anomalies observed in the winter and spring of 2016. In the Weddell Sea, some of this preconditioning was associated with the winter polynyas that appeared that year. These events are linked to strong upwelling in the Weddell Sea and the passage of powerful winter storms. Lastly, we construct an updated seasonal mixed layer heat budget for the Southern Ocean, which is then used to explain the near-record Southern Ocean SSTs that occurred in the summer of 2016--2017. This analysis reveals that the warming maximum was the combined effect of enhanced air-sea heating, reduced northward Ekman transport, and shallower than normal mixed layer depths. From these results, we conclude that the 2016--2017 Southern Ocean SST and SIE anomalies were primarily caused by a serendipitous sequence of anomalous atmospheric and oceanic conditions. These anomalies coincided with an unusual synchronization of tropical and extratropical modes of climate variability.

Author: Cynthia Rosenzweig
Publisher: World Scientific
ISBN: 9813148802
Category : Science
Languages : en
Pages : 444

View

Book Description
The processes and consequences of climate change are extremely heterogeneous, encompassing many different fields of study. Dr David Rind in his career at the NASA Goddard Institute for Space Studies and as a professor at Columbia University has had the opportunity to explore many of these subjects with colleagues from these diverse disciplines. It was therefore natural for the Lectures in Climate Change series to begin with his colleagues contributing lectures on their specific areas of expertise.This first volume, entitled Our Warming Planet: Topics in Climate Dynamics, encompasses topics such as natural and anthropogenic climate forcing, climate modeling, radiation, clouds, atmospheric dynamics/storms, hydrology, clouds, the cryosphere, paleoclimate, sea level rise, agriculture, atmospheric chemistry, and climate change education. Included with this publication are downloadable PowerPoint slides of each lecture for students and teachers around the world to be better able to understand various aspects of climate change.The lectures on climate change processes and consequences provide snapshots of the cutting-edge work being done to understand what may well be the greatest challenge of our time, in a form suitable for classroom presentation.

Author: Stanley S. Jacobs
Publisher: American Geophysical Union
ISBN:
Category : Science
Languages : en
Pages : 400

View

Book Description
In this latest oceanology volume of the Antarctic Research Series, polar scientists describe and model air-sea and ice-ocean interactions, the formation and chemistry of deep and bottom waters, regional circulations, tidal heights and currents, ocean bathymetry, interannual variability and the Antarctic Slope Front.