The Role of Sea Ice in Mediating Atmosphere-ice-ocean Momentum Transfer PDF Download

Author: Samuel Dale Brenner
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

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Book Description
The ongoing loss of Arctic sea ice prompts questions about changes in momentum transfer across the atmosphere-ice-ocean system and potential climate feedback mechanisms, but the role of the ice in mediating that process is not fully understood. To address knowledge gaps about atmosphere-ice-ocean momentum transfer, this study makes use of in situ measurements collected during two recent observational campaigns in the Beaufort Sea: the Marginal Ice Zone (MIZ) program and the Stratified Ocean Dynamics of the Arctic (SODA) program. The research is presented in two parts.Part I develops data processing methods for instrumentation deployed as part of the SODA program while part II uses data from both programs to evaluate controls of sea ice on the ocean surface stress and the associated response in the ocean surface mixed layer (ML). Measurements of upper ocean properties can be challenging in the Arctic Ocean due to environmental conditions, including the need for moored instruments to avoid contact with sea ice. Part I of this work describes methods for developing usable data products from upward-looking Acoustic Doppler Current Profiler (ADCP) measurements on the SODA moorings. This encompasses methods for creating combined data records from vertically-offset ADCPs on the same mooring chain and methods for using ADCPs to estimate surface ML depth and temperature. As ML depth and temperature measurements are not typically possible from subsurface moorings in the Arctic, the approach developed here provides considerable value and could be applied to other extant mooring records to recover information about ML property variability or trends. Building on these measurements, part II considers how sea ice properties, such as concentration and morphology, affect the transfer of momentum from the sea ice to the ocean and the associated upper-ocean dynamics. Ice-ocean drag coefficients, a measure of momentum transfer efficiency, calculated using a force-balance approach from the SODA mooring data show seasonal variations consistent with past observations, but at odds with previous model results.Tests of model parameterizations of drag based on direct observations of under-ice morphology reveal that the model-observation mismatch can be attributed to inaccuracies in empirical translations from bulk geometric properties to detailed geometry statistics, especially under-representation of floe sizes. The mooring measurements further show a seasonal upper-ocean response to surface stress, with minimal energy in ML inertial oscillations under sea ice cover. A simplified momentum budget for the coupled ice-ocean system shows that the seasonality stems from a combination of internal stress in the ice damping the oscillations and seasonal variability in the ocean ML depth. Finally, shipboard measurements from the MIZ program show the evolution of ice-edge-located freshwater front as it reacted to changes in the surface wind stress, raising questions about how sea ice might impact spatial heterogeneity of stress and how that might interact with frontal dynamics. This research shows that boundary layer dynamics and internal ice mechanics both play a role in mediating atmosphere-ice-ocean momentum transfer. The results suggest future trends of more "slippery" ice-ocean boundary layer, and decreasing internal sea ice stress, which could lead to increased sea ice drift speeds and more direct atmosphere-ocean coupling.

Author: Alexander Mchedlishvili
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

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Over the last half a century, the Arctic sea ice extent and volume have been decreasing as a result of the amplified warming taking place in the Arctic. Similarly, the Antarctic summertime sea ice extent maximum has been the lowest in the satellite record for the last three years. As sea ice at both poles is changing in a warming climate, it is necessary to better understand the fundamental processes that determine sea ice properties such as extent, thickness, volume and drift. These processes, namely dynamic and thermodynamic ones, are triggered by the surrounding atmosphere and ocean. The overarching goal of this dissertation is to study dynamic processes while also considering thermodynamic aspects. Chapter 3 delves into the abovementioned dynamic and thermodynamic processes at mesoscale in the study of polynya events and thin sea ice anomalies above Maud Rise in the Antarctic. Chapter 4 looks at parameters that quantify dynamics, specifically at drag coefficients (Cd) that determine the momentum transfer between the atmosphere and sea ice, on a pan-Arctic scale. Finally, Chapter 5 implements the derived estimates of drag from observations into a coupled regional atmosphere-ocean-sea ice model in order to investigate the impact of variable drag on sea ice properties Arctic-wide. The Weddell Sea Polynya (occurring in 1974-1976 and 2016-2017) is an excellent case study in the impact of mesoscale as well as synoptic scale processes on sea ice. My analysis of the events corroborates past studies that identify the Weddell Sea polynya as one that is driven by dynamic as well as thermodynamic processes. In addition, using satellite-borne microwave imaging radiometers, large thin sea ice anomalies have been identified in polynya-free years (2010-2020). Given the reported links between the polynya and different dynamic and thermodynamic ocean and atmosphere processes, our results suggest that when an insufficient amount of these processes are active, a thin sea ice anomaly may emerge instead. The neutral sea ice-atmosphere Cd data-set is the first-ever assessment of drag on both pan- Arctic spatial and sub-yearly temporal scales. Leveraging the high resolution of Ice, Cloud and land Elevation Satellite 2 (IS2), as well as near-coincident Operation IceBridge (OIB) airborne surveys of sea ice topography, it was possible to observe the spatiotemporal evolution of drag from November 2018 to May 2022. My results showed the ice area directly north of the Canadian Archipelago and Greenland to have a Cd consistently above 2.0 × 10-3, while for most of the multiyear ice portion of the Arctic it is typically around ∼1.5 × 10-3. The first-year and young ice portion of the Arctic has a comparatively lower Cd (∼9 × 10-4) with an increase along the marginal ice zone that exceeds 1.5 × 10-3. This dataset was then used to derive a parameterization linking Cd to coincident IS2 sea ice thickness measurements, which was implemented into the regional atmosphere-ocean-sea ice model HIRHAM-NAOSIM. By running the model with and without the implementation, my results showed reasonable albeit small differences between the sea ice properties modelled by the two runs. Using sensitivity studies that varied the coefficients and integration of the Cd parameterization, I was then able to explain the differences observed. The main findings from the model study are that atmospheric and oceanic drag have the opposite effect on both sea ice drift and thickness on a pan-Arctic scale, and that over a period of three years, regardless of the range in drag variability, the impact of drag on sea ice in a coupled model is typically small in magnitude (

Author: Burton G. Hurdle
Publisher: Springer Science & Business Media
ISBN: 1461580358
Category : Science
Languages : en
Pages : 788

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" ... as soon as one has traversed the greater part of the wild sea, one comes upon such a huge quantity of ice that nowhere in the whole world has the like been known." "This ice is of a wonderful nature. It lies at times quite still, as one would expect, with openings or large fjords in it; but sometimes its movement is so strong and rapid as to equal that of a ship running before the wind, and it drifts against the wind as often as with it." Kongespeilet - 1250 A.D. ("The Mirror of Kings") Modern societies require increasing amounts influence on the water mass and on the resulting of scientific information about the environment total environment of the region; therefore, cer tain of its characteristics will necessarily be in whieh they live and work. For the seas this information must describe the air above the sea, included.

Author: Matti Leppäranta
Publisher: Springer Science & Business Media
ISBN: 3642046835
Category : Science
Languages : en
Pages : 370

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Book Description
The Second Edition of The Drift of Sea Ice presents the fundamental laws of sea ice drift which come from the material properties of sea ice and the basic laws of mechanics. The resulting system of equations is analysed for the general properties of sea ice drift, the free drift model and analytical models for ice drift in the presence of internal friction, and the construction of numerical ice drift models is detailed. This second edition of a much lauded work, unique on this topic in the English language, has been revised, updated and expanded with much new information and outlines recent results, in particular in relation to the climate problem, mathematical modelling and ice engineering applications. The current book presents the theory, observations, mathematical modelling techniques, and applications of sea ice drift science. The theory is presented from the beginning on a graduate student level, so that students and researchers coming from other fields such as physical oceanography, meteorology, physics, engineering, environmental sciences or geography can use the book as a source book or self-study material. First the drift ice material is presented ending with the concept of ‘ice state’ – the relevant properties in sea ice dynamics. Ice kinematics observations are widely presented with the mathematical analysis methods, and thereafter come drift ice rheology – to close the triangle material – kinematics – stress. The momentum equation of sea ice is derived in detail and its general properties are carefully analysed. Then follow two chapters on analytical models: free drift and drift in the presence of internal friction: These are very important tools in understanding the dynamical behaviour of sea ice. The last topical chapter is numerical models, which are the modern tool to solve ice dynamics problem in short term and long term problems. The closing chapter summarises sea ice dynamics applications and the need of sea ice dynamic knowledge and gives some final remarks on the future of this branch of science.

Author: Peter Wadhams
Publisher: CRC Press
ISBN: 9789056992965
Category : Science
Languages : en
Pages : 376

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Book Description
ICe in the Ocean examines sea ice and icebergs and their role in the global climate system. It is comprehensive textbook suitablefor students, pure and applied researchers, and anyone interested in the polar oceans; the distribution of sea ice; the mechanisms of growth, development and decay; the thermodynamics and dynamics of sea ice; sea ice deformation and ridge-building; the role of marginal ice zones; the characteristics of icebergs; and the part played by sea ice in the climate system and in the transport of pollutants. An extensive reference list and recommendations for further reading and numerous illustrations, and add to the usefulness of the text.

Author: David N. Thomas
Publisher: John Wiley & Sons
ISBN: 0470756926
Category : Technology & Engineering
Languages : en
Pages : 419

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Book Description
Sea ice, which covers up to 7% of the planet’s surface, is a major component of the world’s oceans, partly driving ocean circulation and global climate patterns. It provides a habitat for a rich diversity of marine organisms, and is an extremely valuable source of information in studies of global climate change and the evolution of present day life forms. Increasingly sea ice is being used as a proxy for extraterrestrial ice covered systems. Sea Ice provides a comprehensive review of our current available knowledge of polar pack ice, the study of which is severely constrained by the logistic difficulties of working in such harsh and remote regions of the earth. The book’s editors, Drs Thomas and Dieckmann have drawn together an impressive group of international contributing authors, providing a well-edited and integrated volume, which will stand for many years as the standard work on the subject. Contents of the book include details of the growth, microstructure and properties of sea ice, large-scale variations in thickness and characteristics, its primary production, micro-and macrobiology, sea ice as a habitat for birds and mammals, sea ice biogeochemistry, particulate flux, and the distribution and significance of palaeo sea ice. Sea Ice 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 on their shelves. David Thomas is at the School of Ocean Sciences, University of Wales, Bangor, UK. Gerhard Dieckmann is at the Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany

Author: Miles McPhee
Publisher: Springer
ISBN: 9780387783345
Category : Science
Languages : en
Pages : 0

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Book Description
At a time when the polar regions are undergoing rapid and unprecedented change, understanding exchanges of momentum, heat and salt at the ice-ocean interface is critical for realistically predicting the future state of sea ice. By offering a measurement platform largely unaffected by surface waves, drifting sea ice provides a unique laboratory for studying aspects of geophysical boundary layer flows that are extremely difficult to measure elsewhere. This book draws on both extensive observations and theoretical principles to develop a concise description of the impact of stress, rotation, and buoyancy on the turbulence scales that control exchanges between the atmosphere and underlying ocean when sea ice is present. Several interesting and unique observational data sets are used to illustrate different aspects of ice-ocean interaction ranging from the impact of salt on melting in the Greenland Sea marginal ice zone, to how nonlinearities in the equation of state for seawater affect mixing in the Weddell Sea. The book’s content, developed from a series of lectures, may be appropriate additional material for upper-level undergraduates and first-year graduate students studying the geophysics of sea ice and planetary boundary layers.

Author: Matti Leppäranta
Publisher: Springer Science & Business Media
ISBN: 3540269703
Category : Science
Languages : en
Pages : 282

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Book Description
This book presents the fundamental laws of sea ice drift, as derived from the material properties of sea ice, the basic laws of mechanics, and the latest modeling techniques. Topics covered include the science of sea ice drift, forecasting velocity based on volume, size and shape, sea ice ridging and remote sensing, modelling of ice conditions, and the role of sea ice drift in oceanography, marine ecology and engineering.

Author: Norbert Untersteiner
Publisher: Springer
ISBN: 1489953523
Category : Science
Languages : en
Pages : 1197

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Book Description
Based on the proceedings of the NATO Advanced Study Institute on Air-Sea-Ice Interaction held September 28-October 10, 1981 in Acquafredda di maratea, Italy. Intent is to present the topic of sea ice in the broad and interdisciplinary context of atmospheric and oceanographic science.

Author: Miles McPhee
Publisher: Springer Science & Business Media
ISBN: 0387783350
Category : Science
Languages : en
Pages : 218

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Book Description
At a time when the polar regions are undergoing rapid and unprecedented change, understanding exchanges of momentum, heat and salt at the ice-ocean interface is critical for realistically predicting the future state of sea ice. By offering a measurement platform largely unaffected by surface waves, drifting sea ice provides a unique laboratory for studying aspects of geophysical boundary layer flows that are extremely difficult to measure elsewhere. This book draws on both extensive observations and theoretical principles to develop a concise description of the impact of stress, rotation, and buoyancy on the turbulence scales that control exchanges between the atmosphere and underlying ocean when sea ice is present. Several interesting and unique observational data sets are used to illustrate different aspects of ice-ocean interaction ranging from the impact of salt on melting in the Greenland Sea marginal ice zone, to how nonlinearities in the equation of state for seawater affect mixing in the Weddell Sea. The book’s content, developed from a series of lectures, may be appropriate additional material for upper-level undergraduates and first-year graduate students studying the geophysics of sea ice and planetary boundary layers.