Download or read book An Intercomparison of Intraseasonal Variability in General Circulation Models and Observations written by and published by . This book was released on 1990 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Intercomparison of Intraseasonal Variability in General Circulation Models and Observations written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-11-13 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: Low frequency oscillations appearing in three GCM seasonal cycle integrations are compared with the analyses of the European Center for Medium Range Weather Forecasting (ECMWF). All three models have the same resolution: 4 deg latitude by 5 deg longitude, with 9 levels. The dominant phase speeds and the differential vertical structure of the heating profiles in the GCMs are in general agreement with current theory involving the positive feedback between latent heating and moist static stability. All three GCMs fail to capture the detailed evolution in the different stages of the development and decay of the oscillation. The results suggest that an improvement in the boundary layer moisture processes may be crucial for a better simulation of the oscillation. Park, Chung-Kyu and Straus, David M. and Lau, Ka-Ming and Schubert, Siegfried D. Goddard Space Flight Center ANNUAL VARIATIONS; ATMOSPHERIC BOUNDARY LAYER; ATMOSPHERIC GENERAL CIRCULATION MODELS; PRESSURE OSCILLATIONS; WEATHER FORECASTING; ATMOSPHERIC HEATING; LOW FREQUENCIES; MOISTURE; TEMPERATURE DISTRIBUTION; VERTICAL DISTRIBUTION; ZONAL FLOW (METEOROLOGY)...
Download or read book Intraseasonal Variability in the Atmosphere Ocean Climate System written by William K.-M. Lau and published by Springer Science & Business Media. This book was released on 2011-10-25 with total page 642 pages. Available in PDF, EPUB and Kindle. Book excerpt: Improving the reliability of long-range forecasts of natural disasters, such as severe weather, droughts and floods, in North America, South America, Africa and the Asian/Australasian monsoon regions is of vital importance to the livelihood of millions of people who are affected by these events. In recent years the significance of major short-term climatic variability, and events such as the El Nino/Southern Oscillation in the Pacific, with its worldwide effect on rainfall patterns, has been all to clearly demonstrated. Understanding and predicting the intra-seasonal variability (ISV) of the ocean and atmosphere is crucial to improving long range environmental forecasts and the reliability of climate change projects through climate models. In the second edition of this classic book on the subject, the authors have updated the original chapters, where appropriate, and added a new chapter that includes short subjects representing substantial new development in ISV research since the publication of the first edition.
Download or read book Climate Variability and Trend on Interannual to centennial Timescales from Global Observations and Atmosphere ocean Model Simulations written by Houk Paek and published by . This book was released on 2013 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: The numerical climate models have provided scientists, policy makers and the general public, crucial information for climate projections since mid-20th century. An international effort to compare and validate the simulations of all major climate models is organized by the Coupled Model Intercomparison Project (CMIP), which has gone through several phases since 1995 with CMIP5 being the state of the art. In parallel, an organized effort to consolidate all observational data in the past century culminates in the creation of several "reanalysis" datasets that are considered the closest representation of the true observation. This study compared the climate variability and trend in the climate model simulations and observations on the timescales ranging from interannual to centennial. The analysis focused on the dynamic climate quantity of zonal-mean zonal wind and global atmospheric angular momentum (AAM), and incorporated multiple datasets from reanalysis and the most recent CMIP3 and CMIP5 archives. For the observation, the validation of AAM by the length-of-day (LOD) and the intercomparison of AAM revealed a good agreement among reanalyses on the interannual and the decadal-to-interdecadal timescales, respectively. But the most significant discrepancies among them are in the long-term mean and long-term trend. For the simulations, the CMIP5 models produced a significantly smaller bias and a narrower ensemble spread of the climatology and trend in the 20th century for AAM compared to CMIP3, while CMIP3 and CMIP5 simulations consistently produced a positive trend for the 20th and 21st century. Both CMIP3 and CMIP5 models produced a wide range of the magnitudes of decadal and interdecadal variability of wind component of AAM (MR) compared to observation. The ensemble means of CMIP3 and CMIP5 are not statistically distinguishable for either the 20th- or 21st-century runs. The in-house atmospheric general circulation model (AGCM) simulations forced by the sea surface temperature (SST) taken from the CMIP5 simulations as lower boundary conditions were carried out. The zonal wind and MR in the CMIP5 simulations are well simulated in the AGCM simulations. This confirmed SST as an important mediator in regulating the global atmospheric changes due to GHG effect.
Download or read book El Ni o written by Henry F. Diaz and published by Cambridge University Press. This book was released on 1992 with total page 510 pages. Available in PDF, EPUB and Kindle. Book excerpt: This 1993 book enhances our understanding of the mechanisms involved in the low frequency behavior of the El Nino/Southern Oscillation (ENSO) phenomenon.
Download or read book Monsoon Dynamics written by James Lighthill and published by Cambridge University Press. This book was released on 1981-03-19 with total page 768 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents a survey of our state of knowledge of the physical and dynamical processes involved in the Asian monsoon. Although traditionally the main emphasis has been on the study of the atmospheric component, it has long been known that the oceans play a vitally important part in determining the occurrence of this spectacular seasonal event. A scientific study of this phenomenon involves a detailed investigation of the dynamical processes which occur in both the atmosphere and the ocean, on timescales on up to at least a year and on spatial scales from a few hundred kilometres or so up to that of the global atmospheric and oceanic circulations. The editors present a coherent survey of each of the meteorological, oceanographic and hydrological aspects and of their implications for weather forecasting and flood prediction. Monsoon Dynamics is a timely survey of a dramatic meteorological phenomenon which will interest meteorologists, climatologists and geophysicists.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 892 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Diagnostic Studies of Extratropical Intraseasonal Variability in the Northern Hemisphere written by Dennis P. Robinson and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive analysis of midlatitude intraseasonal variability in extended integrations of General Circulation Models (GCMs) developed at the National Aeronautics and Space Administration Goddard Space Flight Center is conducted in the first part of this thesis. The model statistics, three-dimensional structure, and dynamical characteristics of storm tracks and large-scale weather regimes are diagnosed and directly compared to parallel observational analyses. Results indicate that several aspects of simulated intraseasonal phenomenon are linked to errors in the zonally asymmetric circulation. During the boreal winter, anomalously large meridional temperature gradients and enhanced zonal winds in the simulations are linked to suppressions in baroclinic wave activity in the models. As a result lower-frequency modes in the GCMs are more strongly driven by baroclinic dynamics. Nonetheless, the GCMs successfully reproduce the North Pacific midwinter suppression phenomenon. In an effort to provide insight into the North Pacific midwinter suppression, the second part of this work stratifies the boreal cool season into three stages, where the early and late (middle) stages approximately correspond to the seasonal maxima (minimum) in synoptic eddy activity that occurs over the North Pacific. Analyses using this unique approach reveal that during the midwinter suppression period, cyclonic perturbations entering the North Pacific storm track core from Asia are already deficient in magnitude compared to early and late winter stages. In both observations and model simulations, the North Pacific midwinter suppression feature is discovered to have a clear organized extension upstream into Siberia. Thus, the final portion of this thesis examines the causes for the midwinter suppression of upper tropospheric Rossby wave packets propagating across Asia prior to entering the North Pacific storm track. The study unveils an increased sensitivity of synoptic-scale wave packets with a large-scale, upper-tropospheric flow pattern over Siberia during midwinter. This interaction with the large-scale pattern over Siberia results in a general dampening of synoptic eddy amplitudes over Asia, which is proposed to be the contributing factor to the North Pacific midwinter suppression phenomenon.
Download or read book Indian Summer Monsoon Variability written by Jasti S. Chowdary and published by Elsevier. This book was released on 2021-08-15 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt: Indian Summer Monsoon Variability: El Niño-Teleconnections and Beyond presents the improved understanding of Indian Monsoon teleconnections (ENSO and Non-ENSO), new advances, and preferred future steps. Special emphasis is given to non-ENSO teleconnections which have been poorly understood for decades. With growing monsoon rainfall extremes across the Indian Subcontinent, a new understanding of monsoon environmental factors that are driven remotely through teleconnections is a trending topic. Finally, the book reviews current understanding ofthe observational and modeling aspects of Indian monsoon teleconnections. This is a must-read for researchers and graduate students in atmospheric science and meteorology. - Presents teleconnections associated with the Indian summer monsoon from a global perspective - Discusses new pathways that connect the remote drivers to Indian summer monsoon variability - Covers a wide range of mechanisms, processes, and science questions in relation to monsoon variability from interannual, decadal to climate change time scales
Download or read book Model Interpretation of Climate Signals written by William K. Lau and published by BiblioGov. This book was released on 2013-08 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is an invited review paper intended to be published as a Chapter in a book entitled "The Global Climate System: Patterns, Processes and Teleconnections" Cambridge University Press. The author begins with an introduction followed by a primer of climate models, including a description of various modeling strategies and methodologies used for climate diagnostics and predictability studies. Results from the CLIVAR Monsoon Model Intercomparison Project (MMIP) were used to illustrate the application of the strategies to modeling the Asian monsoon. It is shown that state-of-the art atmospheric GCMs have reasonable capability in simulating the seasonal mean large scale monsoon circulation, and response to El Nino. However, most models fail to capture the climatological as well as interannual anomalies of regional scale features of the Asian monsoon. These include in general over-estimating the intensity and/or misplacing the locations of the monsoon convection over the Bay of Bengal, and the zones of heavy rainfall near steep topography of the Indian subcontinent, Indonesia, and Indo-China and the Philippines. The intensity of convection in the equatorial Indian Ocean is generally weaker in models compared to observations. Most important, an endemic problem in all models is the weakness and the lack of definition of the Mei-yu rainbelt of the East Asia, in particular the part of the Mei-yu rainbelt over the East China Sea and southern Japan are under-represented. All models seem to possess certain amount of intraseasonal variability, but the monsoon transitions, such as the onset and breaks are less defined compared with the observed. Evidences are provided that a better simulation of the annual cycle and intraseasonal variability is a pre-requisite for better simulation and better prediction of interannual anomalies.
Download or read book Monsoon Meteorology written by Chih-Pei Chang and published by Oxford University Press, USA. This book was released on 1987 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt: Very Good,No Highlights or Markup,all pages are intact.
Download or read book An Intercomparison of the Climates Simulated by 14 Atmospheric General Circulation Models written by CAS/JSC Working Group on Numerical Experimentation and published by . This book was released on 1991 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Global Environmental Change written by National Research Council and published by National Academies Press. This book was released on 1999-09-14 with total page 621 pages. Available in PDF, EPUB and Kindle. Book excerpt: How can we understand and rise to the environmental challenges of global change? One clear answer is to understand the science of global change, not solely in terms of the processes that control changes in climate and the composition of the atmosphere, but in how ecosystems and human society interact with these changes. In the last two decades of the twentieth century, a number of such research effortsâ€"supported by computer and satellite technologyâ€"have been launched. Yet many opportunities for integration remain unexploited, and many fundamental questions remain about the earth's capacity to support a growing human population. This volume encourages a renewed commitment to understanding global change and sets a direction for research in the decade ahead. Through case studies the book explores what can be learned from the lessons of the past 20 years and what are the outstanding scientific questions. Highlights include: Research imperatives and strategies for investigators in the areas of atmospheric chemistry, climate, ecosystem studies, and human dimensions of global change. The context of climate change, including lessons to be gleaned from paleoclimatology. Human responses toâ€"and forcing ofâ€"projected global change. This book offers a comprehensive overview of global change research to date and provides a framework for answering urgent questions.
Download or read book Natural Climate Variability on Decade to Century Time Scales written by National Research Council and published by National Academies Press. This book was released on 1996-08-30 with total page 645 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume reflects the current state of scientific knowledge about natural climate variability on decade-to-century time scales. It covers a wide range of relevant subjects, including the characteristics of the atmosphere and ocean environments as well as the methods used to describe and analyze them, such as proxy data and numerical models. They clearly demonstrate the range, persistence, and magnitude of climate variability as represented by many different indicators. Not only do natural climate variations have important socioeconomic effects, but they must be better understood before possible anthropogenic effects (from greenhouse gas emissions, for instance) can be evaluated. A topical essay introduces each of the disciplines represented, providing the nonscientist with a perspective on the field and linking the papers to the larger issues in climate research. In its conclusions section, the book evaluates progress in the different areas and makes recommendations for the direction and conduct of future climate research. This book, while consisting of technical papers, is also accessible to the interested layperson.
Download or read book El Ni o Southern Oscillation in a Changing Climate written by Michael J. McPhaden and published by John Wiley & Sons. This book was released on 2020-11-24 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive and up-to-date information on Earth’s most dominant year-to-year climate variation The El Niño Southern Oscillation (ENSO) in the Pacific Ocean has major worldwide social and economic consequences through its global scale effects on atmospheric and oceanic circulation, marine and terrestrial ecosystems, and other natural systems. Ongoing climate change is projected to significantly alter ENSO's dynamics and impacts. El Niño Southern Oscillation in a Changing Climate presents the latest theories, models, and observations, and explores the challenges of forecasting ENSO as the climate continues to change. Volume highlights include: Historical background on ENSO and its societal consequences Review of key El Niño (ENSO warm phase) and La Niña (ENSO cold phase) characteristics Mathematical description of the underlying physical processes that generate ENSO variations Conceptual framework for understanding ENSO changes on decadal and longer time scales, including the response to greenhouse gas forcing ENSO impacts on extreme ocean, weather, and climate events, including tropical cyclones, and how ENSO affects fisheries and the global carbon cycle Advances in modeling, paleo-reconstructions, and operational climate forecasting Future projections of ENSO and its impacts Factors influencing ENSO events, such as inter-basin climate interactions and volcanic eruptions The American Geophysical Union promotes discovery in Earth and space science for the benefit of humanity. Its publications disseminate scientific knowledge and provide resources for researchers, students, and professionals. Find out more about this book from this Q&A with the editors.
Download or read book The Global Monsoon System written by Chih-Pei Chang and published by World Scientific. This book was released on 2011 with total page 609 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a current review of the science of monsoon research and forecasting. The contents are based on the invited reviews presented at the World Meteorological Organization''s Fourth International Workshop on Monsoons in late 2008, with subsequent manuscripts revised from 2009 to early 2010. The book builds on the concept that the monsoons in various parts of the globe can be viewed as components of an integrated global monsoon system, while emphasizing that significant region-specific characteristics are present in individual monsoon regions. The topics covered include all major monsoon regions and time scales (mesoscale, synoptic, intraseasonal, interannual, decadal, and climate change). It is intended to provide an updated comprehensive review of the current status of knowledge, modeling capability, and future directions in the research of monsoon systems around the world.
Download or read book Flexible Global Ocean Atmosphere Land System Model written by Tianjun Zhou and published by . This book was released on 2013-11-30 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:
