Download or read book Impact of Turbulence on Hurricane Intensity Forecast written by Sopan Anantha Kurkute and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Global Perspectives On Tropical Cyclones From Science To Mitigation written by Johnny C L Chan and published by World Scientific. This book was released on 2010-04-30 with total page 445 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a completely rewritten, updated and expanded new edition of the original Global Perspectives on Tropical Cyclones published in 1995. It presents a comprehensive review of the state of science and forecasting of tropical cyclones together with the application of this science to disaster mitigation, hence the tag: From Science to Mitigation.Since the previous volume, enormous progress in understanding tropical cyclones has been achieved. These advances range from the theoretical through to ever more sophisticated computer modeling, all underpinned by a vast and growing range of observations from airborne, space and ocean observation platforms. The growth in observational capability is reflected by the inclusion of three new chapters on this topic. The chapter on the effects of climate change on tropical cyclone activity is also new, and appropriate given the recent intense debate on this issue. The advances in the understanding of tropical cyclones which have led to significant improvements in forecasting track, intensity, rainfall and storm surge, are reviewed in detail over three chapters. For the first time, a chapter on seasonal prediction is included. The book concludes with an important chapter on disaster mitigation, which is timely given the enormous loss of life in recent tropical cyclone disasters.World Scientific Series on Asia-Pacific Weather and Climate is indexed in SCOPUS.
Download or read book Landfalling tropical cyclones physical processes forecasting and impacts written by Yihong Duan and published by Frontiers Media SA. This book was released on 2022-12-29 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Tropical cyclone intensity and structure changes Theories observations numerical modeling and forecasting written by Eric Hendricks and published by Frontiers Media SA. This book was released on 2023-09-29 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Turbulent Characteristics in the Hurricane Boundary Layer written by Sunwei Li and published by . This book was released on 2012 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt: As the medium between the sea surface and the upper atmosphere in a hurricane, the Hurricane Boundary Layer (HBL) plays a key role in the overall dynamics of a tropical cyclone, and therefore turbulence exchanges within the HBL deserve a thorough investigation. However, since it is dangerous and difficult to take direct measurements within the HBL, studies of the HBL turbulence processes based on direct observations are rare. Thanks to the newly developed dropwindsonde equipped with a Global Position System (GPS) receiver, it is now possible to measure wind velocities and other meteorological variables with an unprecedented accuracy and resolution in the HBL. To fully utilize dropwindsonde measurements, it is necessary to thoroughly understand its motion characteristics in the measured wind field since its horizontal motions are usually reported as wind measurements. For that reason, the dropwindsonde motion in a pseudo-stochastic wind field with known statistics is simulated. The simulation results illustrate the importance of the wind finding equations introduced by Hock and Franklin (1999) which calculate local winds from dropwindsonde motions. The simulation results show that they are important in reproducing both mean and turbulent wind structures in the HBL. One of its basic assumptions that the dropwindsonde drag coefficient is a constant regardless of the angle of attack is, however, invalidated by the wind tunnel tests conducted in this study. Given that this assumption is essential in both deriving the wind finding equations and in conducting the numerical dropwindsonde motion simulation described above, it is necessary to adapt the dropwindsonde motion model and to repeat the motion simulation to recheck the validity of the wind finding equations demonstrated in the previous simulation. The results validates the wind finding equations although it is derived based on a false assumption that the dropwindsonde drag coefficient is a constant regardless of angles of attack. Moreover, through analyzing the adapted dropwindsonde motion model, a new approach to estimate the vertical wind is proposed which is shown to increase the accuracy in vertical wind estimation by nearly 70%. Based on the findings derived in the dropwindsonde motion simulations, an in-house software package is designed to process the actual dropwindsonde measurements gathered from 1997 to 2010. The in-house software package, showing an effectiveness equivalent to other widely used processing systems, gives users more control over the processing and compositing procedures used to derive the desired statistics of the measured wind field. With the help of this software package, dropwindsonde measurements are processed and composited to produce the mean, turbulence intensity, and turbulent length scale profiles of the HBL. While the mean wind structure confirms the findings made by several previous studies, the turbulence structure reveals that the turbulence diffusivity formulation currently used by the Yonsei University planetary boundary layer scheme, or the YSU scheme, in Weather Research and Forecasting Model(WRF), a widely used hurricane wind simulation package, correctly simulate turbulent mixing in the HBL up to 200m from the sea surface. In a theoretical discussion of the validity of the YSU scheme, it is found that both the velocity scale and height scale used in its turbulence diffusivity formulation should be revised to take into consideration the special turbulence characteristics in the HBL. For the purpose of checking the turbulence diffusivity formulation used in the YSU scheme, high resolution numerical simulations of an idealized tropical cyclone are conducted using WRF. The simulation results show that only revising the HBL height calculation is not adequate to improve the numerical simulation of hurricanes. Therefore, a deeper investigation of the YSU scheme in simulating the HBL turbulence is required.
Download or read book Atmospheric Turbulence written by Adrian F. Tuck and published by Oxford University Press, USA. This book was released on 2008-01-17 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on the direct link between molecular dynamics and atmospheric variation, uniting molecular dynamics, turbulence theory, fluid mechanics and non equilibrium statistical mechanics.
Download or read book Aviation Turbulence written by Robert Sharman and published by Springer. This book was released on 2016-06-27 with total page 529 pages. Available in PDF, EPUB and Kindle. Book excerpt: Anyone who has experienced turbulence in flight knows that it is usually not pleasant, and may wonder why this is so difficult to avoid. The book includes papers by various aviation turbulence researchers and provides background into the nature and causes of atmospheric turbulence that affect aircraft motion, and contains surveys of the latest techniques for remote and in situ sensing and forecasting of the turbulence phenomenon. It provides updates on the state-of-the-art research since earlier studies in the 1960s on clear-air turbulence, explains recent new understanding into turbulence generation by thunderstorms, and summarizes future challenges in turbulence prediction and avoidance.
Download or read book A Study on the Turbulent Characteristics Within the Hurricane Boundary Layer written by Sunwei Li and published by . This book was released on 2012 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt: As the medium between the sea surface and the upper atmosphere in a hurricane, the Hurricane Boundary Layer (HBL) plays a key role in the overall dynamics of a tropical cyclone, and therefore turbulence exchanges within the HBL deserve a thorough investigation. However, since it is dangerous and difficult to take direct measurements within the HBL, studies of the HBL turbulence processes based on direct observations are rare. Thanks to the newly developed dropwindsonde equipped with a Global Position System (GPS) receiver, it is now possible to measure wind velocities and other meteorological variables with an unprecedented accuracy and resolution in the HBL. To fully utilize dropwindsonde measurements, it is necessary to thoroughly understand its motion characteristics in the measured wind field since its horizontal motions are usually reported as wind measurements. For that reason, the dropwindsonde motion in a pseudo-stochastic wind field with known statistics is simulated. The simulation results illustrate the importance of the wind finding equations introduced by Hock and Franklin (1999) which calculate local winds from dropwindsonde motions. The simulation results show that they are important in reproducing both mean and turbulent wind structures in the HBL. One of its basic assumptions that the dropwindsonde drag coefficient is a constant regardless of the angle of attack is, however, invalidated by the wind tunnel tests conducted in this study. Given that this assumption is essential in both deriving the wind finding equations and in conducting the numerical dropwindsonde motion simulation described above, it is necessary to adapt the dropwindsonde motion model and to repeat the motion simulation to recheck the validity of the wind finding equations demonstrated in the previous simulation. The results validates the wind finding equations although it is derived based on a false assumption that the dropwindsonde drag coefficient is a constant regardless of angles of attack. Moreover, through analyzing the adapted dropwindsonde motion model, a new approach to estimate the vertical wind is proposed which is shown to increase the accuracy in vertical wind estimation by nearly 70%. Based on the findings derived in the dropwindsonde motion simulations, an in-house software package is designed to process the actual dropwindsonde measurements gathered from 1997 to 2010. The in-house software package, showing an effectiveness equivalent to other widely used processing systems, gives users more control over the processing and compositing procedures used to derive the desired statistics of the measured wind field. With the help of this software package, dropwindsonde measurements are processed and composited to produce the mean, turbulence intensity, and turbulent length scale profiles of the HBL. While the mean wind structure confirms the findings made by several previous studies, the turbulence structure reveals that the turbulence diffusivity formulation currently used by the Yonsei University planetary boundary layer scheme, or the YSU scheme, in Weather Research and Forecasting Model(WRF), a widely used hurricane wind simulation package, correctly simulate turbulent mixing in the HBL up to 200m from the sea surface. In a theoretical discussion of the validity of the YSU scheme, it is found that both the velocity scale and height scale used in its turbulence diffusivity formulation should be revised to take into consideration the special turbulence characteristics in the HBL. For the purpose of checking the turbulence diffusivity formulation used in the YSU scheme, high resolution numerical simulations of an idealized tropical cyclone are conducted using WRF. The simulation results show that only revising the HBL height calculation is not adequate to improve the numerical simulation of hurricanes. Therefore, a deeper investigation of the YSU scheme in simulating the HBL turbulence is required.
Download or read book Dynamics and Predictability of Large Scale High Impact Weather and Climate Events written by Jianping Li and published by Cambridge University Press. This book was released on 2016-03-24 with total page 371 pages. Available in PDF, EPUB and Kindle. Book excerpt: Based largely on an International Commission on Dynamical Meteorology (ICDM) workshop, this timely volume, written by leading researchers in the field, covers a range of important research issues related to high-impact weather and extreme climate events. Dynamical linkages between these extremes and various atmospheric and ocean phenomena are examined, including Atlantic Multidecadal, North Atlantic, and Madden–Julian Oscillations; Annular Modes; tropical cyclones; and Asian monsoons. This book also examines the predictability of high-impact weather and extreme climate events on multiple time scales. Highlighting recent research and new advances in the field, this book enhances understanding of dynamical and physical processes associated with these events to help managers and policy makers make informed decisions to manage risk and prevent or mitigate disasters. It also provides guidance on future research directions in atmospheric science, meteorology, climate science, and weather forecasting, for experts and young scientists.
Download or read book Coarse Grained Simulation and Turbulent Mixing written by Fenando F. Grinstein and published by Cambridge University Press. This book was released on 2016-06-30 with total page 481 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reviews our current understanding of the subject. For graduate students and researchers in computational fluid dynamics and turbulence.
Download or read book Tropical Cyclones written by Roger K. Smith and published by Elsevier. This book was released on 2023-09-22 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tropical cyclones are a major threat to life and property, even in the formative stages of their development. They include a number of different hazards that individually can cause significant impacts, such as extreme winds, storm surge, flooding, tornadoes, and lightning. Tropical Cyclones: Observations and Basic Processes provides a modern overview of the theory and observations of tropical cyclone structure and behavior. The book begins by summarizing key observations of the structure, evolution, and formation of tropical cyclones. It goes on to develop a theoretical foundation for a basic understanding of tropical cyclone behavior during the storm’s life cycle. Horizontally two-dimensional dynamics of vortex motion and other non-axisymmetric features are considered first before tackling the axisymmetric balance dynamics involving the overturning circulation. Following a review of moist convective processes, later chapters focus mainly on a range of three-dimensional aspects of the tropical cyclone life cycle. Building from first principles, the book provides a state-of-the-art summary of the fundamentals of tropical cyclones aimed at advanced undergraduates, graduate students, tropical meteorologists, and researchers. Members of the Royal Meteorological Society are eligible for a 35% discount on all Developments in Weather and Climate Science series titles. See the RMetS member dashboard for the discount code. Develops a systematic foundation for understanding tropical cyclone dynamics and thermodynamics in two and three dimensions Provides a detailed appraisal of steady-state models and the widely accepted, but enigmatic, WISHE intensification theories Applies the new ideas developed in the book to a range of basic problems, including observational tests of the theory
Download or read book The National Windstorm Impact Reduction Program written by United States. Congress. House. Committee on Science and Technology (2007). Subcommittee on Technology and Innovation and published by . This book was released on 2008 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aviation Weather for Pilots and Flight Operations Personnel written by United States. Federal Aviation Administration and published by . This book was released on 1975 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ask the Pilot written by Patrick Smith and published by Penguin. This book was released on 2004 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Though we routinely take to the air, for many of us flying remains a mystery. Few of us understand the how and why of jetting from New York to London in six hours. How does a plane stay in the air? Can turbulence bring it down? What is windshear? How good are the security checks? Patrick Smith, an airline pilot and author of Salon.com's popular column, "Ask the Pilot," unravels the secrets and tells you all there is to know about the strange and fascinating world of commercial flight. He offers: A nuts and bolts explanation of how planes fly Insights into safety and security Straight talk about turbulence, air traffic control, windshear, and crashes The history, color, and controversy of the world's airlines The awe and oddity of being a pilot The poetry and drama of airplanes, airports, and traveling abroad In a series of frank, often funny explanations and essays, Smith speaks eloquently to our fears and curiosities, incorporating anecdotes, memoir, and a life's passion for flight. He tackles our toughest concerns, debunks conspiracy theories and myths, and in a rarely heard voice dares to return a dash of romance and glamour to air travel.
Download or read book Improving Hurricane Intensity Forecasts Using 4DVAR Data Assimilation of Airborne Doppler Radar Winds written by Patricia Sánchez-Rodríguez and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the last decades, researchers have focused on improving tropical cyclone (TC) forecasts. Accurate TC predictions are very important in order to protect life and property. Scientists examine two important pieces regarding TC prediction: where the storm is going and how strong it will be in the future. These are referred as track and intensity forecasts. TC track forecast has improved tremendously over the last several decades. However, hurricane intensity forecasts continue to be a great challenge in operational and research communities. Previous studies have found that the lack of progress in intensity forecasts is partly due to the lag in the ability to specify the initial vortex in the numerical weather prediction (NWP) model, in addition to the lag in representing the observed inner-core storm intensity, structure and internal dynamics. Researches have introduced various data assimilation (DA) techniques to address the problem of determining the initial vortex. However, in order to better represent these features, there must be sufficient observations in the inner-core region along with a data assimilation method that can effectively use the data to accurately estimate the initial vortex. Some of the challenges in the TC data assimilation are: (1) scarcity of systematic data assimilation in the inner-core region, and/or, (2) absence of enough information about this region, and/or (3) the model resolution is inadequate to capture the structures at these smaller scales. This study examines the impact of assimilating high-resolution inner-core Airborne Doppler Radar (ADR) winds on two major hurricanes, Ike (2008) and Earl (2010). The primary objective is to understand its impact in the initial vortex structure and how it translates to the resulting forecasts. With the development of advanced data assimilation techniques, ADR data can improve the specification of the vortex and potentially improve intensity and structure forecasts. Nevertheless, there are two important factors that can affect the effectiveness of the method: (1) resolution on the grid where DA is performed and (2) the background error covariance used. This work focuses on improving the 4-Dimensional Variational (4DVar) data assimilation technique by using a high-resolution DA domain of 4-km in order to better represent convective scales features and by generating a new static background error covariance more suitable for the current DA experiment. This static error covariance includes the vortex structure information. The impacts of these two aspects were revealed by comparing the analyses and forecasts generated by 4DVar with relatively coarse resolution of 12-km that used the standard background error covariance file (that do not contain any vortex information), a 4DVar at 4-km that used the same background error covariance, and with a 4DVar at 4-km that used the newly generated covariance. This method is first applied on Hurricane Ike. The second experiment performed on Hurricane Earl only included one 4DVar setup: 4-km DA domain with the new static covariance that contains the vortex information. The results for Hurricane Ike experiment showed that increasing the resolution from 12-km to 4-km in 4DVar largely improved the initial vortex structure, enhancing the small eye and the inner-wind maximum. The newly generated vortex specific background covariance used in 4DVar helped to remove some unrealistic features in the wind field showed by the 4-km 4DVar that used the non-vortex static covariance. The adjustment in the initial condition brought the intensity and structure forecast to be in better agreement wit the observations. The mean errors of the maximum wind speed and track forecasts by both 4-km 4DVar experiments were smaller than those by the 12-km 4DVar. In contrast, the mean errors of the sea-level pressure forecast showed that the 12-km 4DVar produced a lower pressure at earlier stages of the forecast. This was attributed to the fact that in the higher-resolution 4DVar analyses, the model was not able to maintain the very small eye, double eyewall and strong pressure gradient features for a longer time. Detailed diagnostics of the surface structure revealed that the asymmetry was well maintained by all the 4DVar cases. However the 4-km 4DVar that used the vortex-specific background covariance gave a better fit with the observations. The control experiment in which no data was assimilated did not develop the inner-core structure and continuously over-estimated the storm intensity. Results from the second experiment performed on Hurricane Earl further demonstrated the advantages of using 4DVar to correct the initial conditions of a hurricane forecast model. For this case, the ADR winds were continuously assimilated during a period of 5 days. Overall the analyses showed that having continuous DA events better estimated the long-term intensity of the storm. The errors of the 4DVar intensity forecasts were evidently smaller than the forecasts with no DA (non-DA) initialized with GFS. The initial conditions were clearly adjusted to match the observed structure. Detailed verification of vertical structures showed that the 4DVar analyses constantly improved the inner-core structure reproducing the inner-wind maximum and maintaining the small eye during the intervening forecasts. This work also demonstrated one of the advantages of assimilating 3D winds in 4DVar since it was able to simulate the deepening and strengthening of the vortex during the rapid intensification event clearly observed by the ADR data.
Download or read book Hurricanes and Climate Change written by James B. Elsner and published by Springer Science & Business Media. This book was released on 2010-01-23 with total page 425 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent studies suggest that tropical cyclones are more powerful than in the past with the most dramatic increase in the North Atlantic. The increase is correlated with an increase in ocean temperature. A debate concerns the nature of these increases with some scientists attributing them to a natural climate fluctuation and others suggesting climate change related to anthropogenic increases in forcing from greenhouse gases. A Summit on Hurricanes and Climate Change was held during the spring of 2007 on the island of Crete that brought together leading academics and researchers on both sides of the scientific debate to discuss new research and express opinions about what will happen in the future with regard to hurricane activity. This proceedings volume highlights the state-of-the-science research into various aspects of the hurricane-climate connection. It is likely that the science presented here will lead to new research that will help answer crucial questions about our sustainable future.
Download or read book Hurricanes and Climate Change written by Jennifer M. Collins and published by Springer. This book was released on 2017-02-20 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides research that shows tropical cyclones are more powerful than in the past with the most dramatic increases occurring over the North Atlantic and with the strongest hurricanes. Although such increases are correlated with warming oceans and are consistent with the thermodynamic theory of hurricane intensity, there remains doubt about the interpretation, integrity, and meaning of these results. Arising from the 5th International Summit on Hurricanes and Climate Change, this book contains new research on topics related to hurricanes and climate change. Bringing together international leading academics and researchers on various sides of the debate, the book discusses new research and expresses opinions about what is happening and what might happen in the future with regard to regional and global hurricane (tropical cyclone) activity.
