Deep Convection and Deep Water Formation in the Oceans

Deep Convection and Deep Water Formation in the Oceans

Author: Simon Chu

Publisher: Elsevier

Published: 1991-09-17

Total Pages: 395

ISBN-13: 0080870953

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This book contains articles presenting current knowledge about the formation and renewal of deep waters in the ocean. These articles were presented at an international workshop at the Naval Postgraduate School in Monterey in March 1990. It is the first book entirely devoted to the topic of deep water formation in which articles have been both selected and reviewed, and it is also the first time authors have addressed both surface and deep mixed layers. Highlighted are: past and recent observations (description and analysis), concepts and models, and modern techniques for future research. Thanks to spectacular advances realised in computing sciences over the last twenty years this volume includes a number of sophisticated numerical models. Observational as well as theoretical studies are presented and a clear distinction is established between open-ocean deep convection and shelf processes, both leading to deep- and bottom-water formation. The main subject addressed is the physical mechanism by which the deep water in the ocean can be renewed. Ventilation occurs at the surface in areas called the gills, where water is mixed and oxygenated before sinking and spreading in the abyss of the deep ocean. This phenomenon is a very active area for both experimentalists and theoreticians because of its strong implications for the understanding of the world ocean circulation and Earth climate. This major theme sheds light on specific and complex processes happening in very restricted areas still controlling three quarters of the total volume of the ocean. All articles include illustrations and a bibliography. This book will be of particular interest to physical oceanographers, earth scientists, environmentalists and climatologists.


The Role of Large-scale Organisation of Convection for Tropical Weather and Climate

The Role of Large-scale Organisation of Convection for Tropical Weather and Climate

Author: Boon Sze Jackson Tan

Publisher:

Published: 2014

Total Pages: 224

ISBN-13:

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Tropical deep convection is a critical process in the climate system, influencing quantities such as cloud cover, precipitation and circulation. Despite its importance, convection is poorly represented in global climate models (GCMs). This shortcoming manifests through significant model biases such as in tropical clouds, precipitation and variability on various time scales, and limits our ability to make accurate projections such as changes in rainfall patterns in a warming climate. Due to the coarse resolution of GCMs, convection has to be represented through parametrisation schemes, in which the subgrid-scale behaviour of convection is determined through the resolved large-scale variables. However, our understanding of the relationship between large-scale variables and convection of different degrees of organisation is limited.In this thesis, we investigate the properties and organisation of tropical convection using cloud regimes, with the aim of improving the representation of convection in models. These cloud regimes are derived from the International Satellite Cloud Climatology Project and they identify various states of convection at a resolution comparable to a GCM. These states range from convectively-suppressed environments to a convectively-active atmosphere of congestus clouds and one with cirrus clouds to, most importantly, a regime of organised deep convection.Using these cloud regimes as proxies for different states of convection, we examine its relationship to large-scale variables. Compositing the cloud regimes with traditional measures of convection, we ascertain that they indeed represent different states of convection. Relating them to large-scale variables, we discover that the environments of different convective states are statistically distinct but possess considerable overlap, a result consistent with the stochastic nature of the relationship between convection and large-scale variables. This motivates us to use our knowledge of this relationship to investigate convective organisation in statistical models of varying complexity. After extending the resolution of the regimes from one day to three hours through an innovative technique, we model them statistically using its large-scale environment and infer that a stochastic parametrisation scheme that ignores spatial and temporal memory may struggle to reproduce deep convection organised beyond the grid box and time step. This outcome is worrying because an analysis of the time-series of these regimes suggests that organised deep convection has increased in the past twenty-seven years, driving a corresponding change in the spatial trends of precipitation. Therefore, advancing our understanding of deep convection and addressing deficiencies in its representation in GCMs are of paramount importance.


Deep Convection and Deep Water Formation in the Oceans

Deep Convection and Deep Water Formation in the Oceans

Author: P. C. Chu

Publisher: Elsevier Science Limited

Published: 1991

Total Pages: 382

ISBN-13: 9780444887641

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This book contains articles presenting current knowledge about the formation and renewal of deep waters in the ocean. These articles were presented at an international workshop at the Naval Postgraduate School in Monterey in March 1990. It is the first book entirely devoted to the topic of deep water formation in which articles have been both selected and reviewed, and it is also the first time authors have addressed both surface and deep mixed layers. Highlighted are: past and recent observations (description and analysis), concepts and models, and modern techniques for future research. Thanks to spectacular advances realised in computing sciences over the last twenty years this volume includes a number of sophisticated numerical models. Observational as well as theoretical studies are presented and a clear distinction is established between open-ocean deep convection and shelf processes, both leading to deep- and bottom-water formation. The main subject addressed is the physical mechanism by which the deep water in the ocean can be renewed. Ventilation occurs at the surface in areas called the gills , where water is mixed and oxygenated before sinking and spreading in the abyss of the deep ocean. This phenomenon is a very active area for both experimentalists and theoreticians because of its strong implications for the understanding of the world ocean circulation and Earth climate. This major theme sheds light on specific and complex processes happening in very restricted areas still controlling three quarters of the total volume of the ocean. All articles include illustrations and a bibliography. This book will be of particular interest to physical oceanographers, earth scientists, environmentalists and climatologists.


Dynamics of the Tropical Atmosphere and Oceans

Dynamics of the Tropical Atmosphere and Oceans

Author: Peter J. Webster

Publisher: John Wiley & Sons

Published: 2020-06-08

Total Pages: 529

ISBN-13: 0470662565

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This book presents a unique and comprehensive view of the fundamental dynamical and thermodynamic principles underlying the large circulations of the coupled ocean-atmosphere system Dynamics of The Tropical Atmosphere and Oceans provides a detailed description of macroscale tropical circulation systems such as the monsoon, the Hadley and Walker Circulations, El Niño, and the tropical ocean warm pool. These macroscale circulations interact with a myriad of higher frequency systems, ranging from convective cloud systems to migrating equatorial waves that attend the low-frequency background flow. Towards understanding and predicting these circulation systems. A comprehensive overview of the dynamics and thermodynamics of large-scale tropical atmosphere and oceans is presented using both a “reductionist” and “holistic” perspectives of the coupled tropical system. The reductionist perspective provides a detailed description of the individual elements of the ocean and atmospheric circulations. The physical nature of each component of the tropical circulation such as the Hadley and Walker circulations, the monsoon, the incursion of extratropical phenomena into the tropics, precipitation distributions, equatorial waves and disturbances described in detail. The holistic perspective provides a physical description of how the collection of the individual components produces the observed tropical weather and climate. How the collective tropical processes determine the tropical circulation and their role in global weather and climate is provided in a series of overlapping theoretical and modelling constructs. The structure of the book follows a graduated framework. Following a detailed description of tropical phenomenology, the reader is introduced to dynamical and thermodynamical constraints that guide the planetary climate and establish a critical role for the tropics. Equatorial wave theory is developed for simple and complex background flows, including the critical role played by moist processes. The manner in which the tropics and the extratropics interact is then described, followed by a discussion of the physics behind the subtropical and near-equatorial precipitation including arid regions. The El Niño phenomena and the monsoon circulations are discussed, including their covariance and predictability. Finally, the changing structure of the tropics is discussed in terms of the extent of the tropical ocean warm pool and its relationship to the intensity of global convection and climate change. Dynamics of the Tropical Atmosphere and Oceans is aimed at advanced undergraduate and early career graduate students. It also serves as an excellent general reference book for scientists interested in tropical circulations and their relationship with the broader climate system.


Cloud-Resolving Modeling of Convective Processes

Cloud-Resolving Modeling of Convective Processes

Author: Shouting Gao

Publisher: Springer Science & Business Media

Published: 2008-04-03

Total Pages: 213

ISBN-13: 1402082762

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Clouds and cloud systems and their interactions with larger scales of motion, radiation, and the Earth’s surface are extremely important parts of weather and climate systems. Their treatment in weather forecast and climate models is a significant source of errors and uncertainty. As computer power increases, it is beginning to be possible to explicitly resolve cloud and precipitation processes in these models, presenting opportunities for improving precipitation forecasts and larger-scale phenomena such as tropical cyclones which depend critically on cloud and precipitation physics. This book by Professor Shouting Gao of the Institute of Atmospheric Physics in Beijing and Xiaofan Li of NOAA’s National Environmental Satellite Data and Information Services (NESDIS) presents an update and review of results of high-resolution, mostly two-dimensional models of clouds and precipitation and their interactions with larger scales of motion and the Earth’s surface. It provides a thorough description of cloud and precipitation physics, including basic governing equations and related physics, such as phase changes of water, radiation and mixing. Model results are compared with observations from the 1992-93 Tropical Ocean Global Atmosphere Coupled Ocean Atmosphere Response Experiment (TOGA COARE) experiment. The importance of the ocean to tropical convective systems is clearly shown here in the numerical results of simulations with their air-sea coupled modeling system. While the focus is on tropical convection, the methodology and applicability can be extended to cloud and precipitation processes elsewhere. The results described in this well-written book form a solid foundation for future high-resolution model weather forecasts and climate simulations that resolve clouds explicitly in three dimensions—a future that has great promise for the understanding and prediction of weather and climate for the great benefit of society.


The Ocean and Cryosphere in a Changing Climate

The Ocean and Cryosphere in a Changing Climate

Author: Intergovernmental Panel on Climate Change (IPCC)

Publisher: Cambridge University Press

Published: 2022-04-30

Total Pages: 755

ISBN-13: 9781009157971

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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.


Abrupt Climate Change

Abrupt Climate Change

Author: National Research Council

Publisher: National Academies Press

Published: 2002-04-23

Total Pages: 252

ISBN-13: 0309133041

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The climate record for the past 100,000 years clearly indicates that the climate system has undergone periodic-and often extreme-shifts, sometimes in as little as a decade or less. The causes of abrupt climate changes have not been clearly established, but the triggering of events is likely to be the result of multiple natural processes. Abrupt climate changes of the magnitude seen in the past would have far-reaching implications for human society and ecosystems, including major impacts on energy consumption and water supply demands. Could such a change happen again? Are human activities exacerbating the likelihood of abrupt climate change? What are the potential societal consequences of such a change? Abrupt Climate Change: Inevitable Surprises looks at the current scientific evidence and theoretical understanding to describe what is currently known about abrupt climate change, including patterns and magnitudes, mechanisms, and probability of occurrence. It identifies critical knowledge gaps concerning the potential for future abrupt changes, including those aspects of change most important to society and economies, and outlines a research strategy to close those gaps. Based on the best and most current research available, this book surveys the history of climate change and makes a series of specific recommendations for the future.