Download or read book Representation of the Tropical Intraseasonal Variability and Its Impact on Seasonal Predictability in a Multi model Ensemble written by and published by . This book was released on 2007 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Representation of the Tropical Intraseasonal Variability and Its Impact on Seasonal Predictability in a Multi mode Ensemble written by and published by . This book was released on 2007 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Next Generation Earth System Prediction written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2016-08-22 with total page 351 pages. Available in PDF, EPUB and Kindle. Book excerpt: As the nation's economic activities, security concerns, and stewardship of natural resources become increasingly complex and globally interrelated, they become ever more sensitive to adverse impacts from weather, climate, and other natural phenomena. For several decades, forecasts with lead times of a few days for weather and other environmental phenomena have yielded valuable information to improve decision-making across all sectors of society. Developing the capability to forecast environmental conditions and disruptive events several weeks and months in advance could dramatically increase the value and benefit of environmental predictions, saving lives, protecting property, increasing economic vitality, protecting the environment, and informing policy choices. Over the past decade, the ability to forecast weather and climate conditions on subseasonal to seasonal (S2S) timescales, i.e., two to fifty-two weeks in advance, has improved substantially. Although significant progress has been made, much work remains to make S2S predictions skillful enough, as well as optimally tailored and communicated, to enable widespread use. Next Generation Earth System Predictions presents a ten-year U.S. research agenda that increases the nation's S2S research and modeling capability, advances S2S forecasting, and aids in decision making at medium and extended lead times.
Download or read book Assessment of Intraseasonal to Interannual Climate Prediction and Predictability written by National Research Council and published by National Academies Press. This book was released on 2010-09-08 with total page 193 pages. Available in PDF, EPUB and Kindle. Book excerpt: More accurate forecasts of climate conditions over time periods of weeks to a few years could help people plan agricultural activities, mitigate drought, and manage energy resources, amongst other activities; however, current forecast systems have limited ability on these time- scales. Models for such climate forecasts must take into account complex interactions among the ocean, atmosphere, and land surface. Such processes can be difficult to represent realistically. To improve the quality of forecasts, this book makes recommendations about the development of the tools used in forecasting and about specific research goals for improving understanding of sources of predictability. To improve the accessibility of these forecasts to decision-makers and researchers, this book also suggests best practices to improve how forecasts are made and disseminated.
Download or read book Sub seasonal to Seasonal Prediction written by Andrew Robertson and published by Elsevier. This book was released on 2018-10-19 with total page 585 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Gap Between Weather and Climate Forecasting: Sub-seasonal to Seasonal Prediction is an ideal reference for researchers and practitioners across the range of disciplines involved in the science, modeling, forecasting and application of this new frontier in sub-seasonal to seasonal (S2S) prediction. It provides an accessible, yet rigorous, introduction to the scientific principles and sources of predictability through the unique challenges of numerical simulation and forecasting with state-of-science modeling codes and supercomputers. Additional coverage includes the prospects for developing applications to trigger early action decisions to lessen weather catastrophes, minimize costly damage, and optimize operator decisions. The book consists of a set of contributed chapters solicited from experts and leaders in the fields of S2S predictability science, numerical modeling, operational forecasting, and developing application sectors. The introduction and conclusion, written by the co-editors, provides historical perspective, unique synthesis and prospects, and emerging opportunities in this exciting, complex and interdisciplinary field. Contains contributed chapters from leaders and experts in sub-seasonal to seasonal science, forecasting and applications Provides a one-stop shop for graduate students, academic and applied researchers, and practitioners in an emerging and interdisciplinary field Offers a synthesis of the state of S2S science through the use of concrete examples, enabling potential users of S2S forecasts to quickly grasp the potential for application in their own decision-making Includes a broad set of topics, illustrated with graphic examples, that highlight interdisciplinary linkages
Download or read book Assessment of Intraseasonal to Interannual Climate Prediction and Predictability written by National Research Council and published by National Academies Press. This book was released on 2010-10-08 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: More accurate forecasts of climate conditions over time periods of weeks to a few years could help people plan agricultural activities, mitigate drought, and manage energy resources, amongst other activities; however, current forecast systems have limited ability on these time- scales. Models for such climate forecasts must take into account complex interactions among the ocean, atmosphere, and land surface. Such processes can be difficult to represent realistically. To improve the quality of forecasts, this book makes recommendations about the development of the tools used in forecasting and about specific research goals for improving understanding of sources of predictability. To improve the accessibility of these forecasts to decision-makers and researchers, this book also suggests best practices to improve how forecasts are made and disseminated.
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 Origins and predictability of the intraseasonal to interannual variabilities of regional climate written by Zhiwei Zhu and published by Frontiers Media SA. This book was released on 2023-01-13 with total page 395 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Tropical Intraseasonal Variability and the Stochastic Skeleton Method written by Andrew J. Majda and published by Springer Nature. This book was released on 2019-09-24 with total page 123 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this text, modern applied mathematics and physical insight are used to construct the simplest and first nonlinear dynamical model for the Madden-Julian oscillation (MJO), i.e. the stochastic skeleton model. This model captures the fundamental features of the MJO and offers a theoretical prediction of its structure, leading to new detailed methods to identify it in observational data. The text contributes to understanding and predicting intraseasonal variability, which remains a challenging task in contemporary climate, atmospheric, and oceanic science. In the tropics, the Madden-Julian oscillation (MJO) is the dominant component of intraseasonal variability. One of the strengths of this text is demonstrating how a blend of modern applied mathematical tools, including linear and nonlinear partial differential equations (PDEs), simple stochastic modeling, and numerical algorithms, have been used in conjunction with physical insight to create the model. These tools are also applied in developing several extensions of the model in order to capture additional features of the MJO, including its refined vertical structure and its interactions with the extratropics. This book is of interest to graduate students, postdocs, and senior researchers in pure and applied mathematics, physics, engineering, and climate, atmospheric, and oceanic science interested in turbulent dynamical systems as well as other complex systems.
Download or read book The Role of Sub seasonal Tropical Convective Variability for the Extratropical Response to ENSO written by Erik T. Swenson and published by . This book was released on 2012 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The boreal winter extratropical response to tropical heating associated with a significant El Niño Southern Oscillation (ENSO) event has been understood primarily in terms of a seasonal average. However, the development and variability of the response forced by a highly sub-seasonally variable atmospheric forcing is still unclear. Significant modes of sub-seasonal tropical convective variability exist that have well documented transient impacts on the extratropics, e.g. the Madden-Julian Oscillation (MJO). Does sub-seasonal tropical convective variability impact the seasonal mean extratropical response? If so, what matters for the response: short-lived strong events or more persistent moderate events? Does sub-seasonal convective variability have implications for predictability during El Niño? Using the Community Atmospheric Model v. 4.0 (CAM4) of the National Center for Atmospheric Research, the response to ENSO is simulated using large ensembles of seasonal integrations forced with observed SST from multiple El Niño events. We decompose the diabatic heating rate (Q) across the tropical Indo-Pacific in terms of temporal and intra-ensemble variability. We then repeat the simulations by prescribing subsets of Q in an effort to diagnose the impact of sub-seasonal and intra-ensemble Q variability. Neglecting sub-seasonal Q variability has a systematic impact on the response, generally extending the Pacific jet and deepening upper-level heights across the North Pacific. A local enhancement is simulated in tropical upper-level divergence, likely related to the vertical redistribution of Q resulting from averaging together vertical profiles associated with moderate and deep convection. Persistence may also play a role. When prescribing nearly all Q variability (for frequencies greater than one day), we find that Q-circulation coupling is locally unimportant, i.e. the temporal evolution, mean, and variance of upper-level divergence from a coupled control simulation are reproducible. However, interestingly the amplification of the extratropical response to El Niño is still simulated. It follows that these differences are attributed to the neglect of tropical-extratropical two-way coupling. This is the primary finding of the study and suggests that the extratropical response to a significant El Niño event is not simply a forced response to tropical heating. Regarding the variability of the response to El Niño, we find a robust relationship in the seasonal mean ensemble spread, linking Q variations in the west/central tropical Pacific and extratropical fluctuations projecting onto the Arctic Oscillation (AO). This mode accounts for about a third of the ensemble spread (in 200 hPa geopotential height). Previous studies have revealed a similar relationship in observed interannual variability and have simulated the tropically forced component. In CAM4, this relationship in the ensemble spread is only evident during El Niño and is the dominant contributor to the enhanced ensemble spread simulated during El Niño, acting to lower predictability of the response. Extratropical forcing of the tropics is important for this mode, as prescribing Q variability weakens the relationship and cannot reproduce the enhancement in spread. We find that this relationship emerges as residue of a low frequency sub-seasonal tropical-extratropical coupled mode for which a significant extratropical influence is evident. Over the Pacific, coherent interaction is simulated between evolving persistent planetary waves and convectively coupled waves bearing a resemblance to equatorial Kelvin waves or MJO-like behavior. We hypothesize that the two-way tropical-extratropical interaction for this mode acts to weaken the extratropical response to El Niño.
Download or read book The Impact of Air sea Interactions on the Simulation of Tropical Intraseasonal Variability written by Kathy Pegion and published by . This book was released on 2007 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Impact of Air sea Coupling on Tropical Intraseasonal Variability Simulation and Predictability written by Kathleen V. Pegion and published by . This book was released on 2007 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: A coupled interactive ensemble technique is also applied to the CFS to determine the relative importance of internal atmospheric dynamics and coupled air-sea feedbacks in the interannual and intraseasonal variability in the CFS. A 40-year interactive ensemble simulation has been performed with the CFS. By comparing this simulation to the standard coupled simulation and the uncoupled simulation, we estimate the importance of internal atmospheric dynamics to the interannual and intraseasonal variability in the CFS.
Download or read book The Impact of Air sea Interactions on the Predictability of the Tropical Intraseasonal Oscillation written by Kathy Pegion and published by . This book was released on 2007 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Decadal Climate Variability written by David L.T. Anderson and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt: On decadal time scales, climate change may result not only from man-made causes, but also from natural processes. This book brings together theoretical conceptions of the physical mechanisms of climate change with observational evidence of these changes. The following key topics are included: Observed Climatic Variability, Predictability of the Atmosphere and Oceans from Days to Decades, and Mechanisms for Decadal to Centennial Climate Variability. Further, there are specialised contributions on the role of the oceanic circulation in climate change. The authors are renowned for their pedagogical skills, and the book is primarily designed for beginners in the field, who have a background in physical science. In addition, it is an invaluable source of information for scientists seeking an overview on climate dynamics.
Download or read book An Analysis of Multi model Ensemble for Seasonal Climate Predictions written by Xiaoqin Yan and published by . This book was released on 2011 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: "In this study, the superiorities of the super ensemble for seasonal climate prediction are investigated based on the 500mb geopotential height (GPH500) hindcasts produced by four Canadian seasonal climate prediction models. The investigations are cared out mainly in two aspects: i) a comprehensive evaluation of predictions for each grid over the global domain by the deterministic, probabilistic and potential prediction skill measures; 2) the Empirical Orthogonal Function (EOF) and Maximum Signal-to-Noise (MSN) EOF analyses in the northern hemisphere (NH). It is found that improvements of the super ensemble are mainly due to the increase of ensemble size in the med-high latitudes, and the offsets of model uncertainties in the tropical regions. Measures of temporal correlation coefficient (COOR), the relative root mean square error (RRMSE), reliability (REL) are more affected by the ensemble size; whereas resolution (RES) is sensitive to the offsets of model uncertainties. In addition, the super ensemble shows advantages in both EOF and MSN EOF analyses. The contributions of the sea surface temperature anomaly (SSTA) to the seasonal mean climate predictability are closely related to El Niño-Southern Oscillation (ENSO) forcing."--P. ii.
Download or read book 2005 Joint Assembly written by American Geophysical Union. Joint Assembly and published by . This book was released on 2005 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Prediction and Predictability of North American Seasonal Climate Variability written by Johnna M. Infanti and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Monthly and seasonal climate prediction of variables such as precipitation, temperature, and sea surface temperature (SST) is of current interest in the scientific research community, and also has implications for users in the agricultural and water management domains, among others. This dissertation studies a variety of approaches to seasonal climate prediction of variables over North America, including both climate prediction systems and methods of analysis. We utilize the North American Multi-Model Ensemble (NMME) System for Intra-Seasonal to Inter-Annual Prediction (ISI) to study seasonal climate prediction skill over North America. We also use the Community Climate System Model version 4.0 (CCSM4) to preformed targeted climate prediction experiments to study contributions to skill or predictability from SSTs, land and atmosphere initialization, and ocean-atmosphere coupling. While all can be considered important for predictions, we show that for winter predictions, SST errors are a leading cause in forecast degradation, and improvement of SSTs causes a significant improvement in skill. Climate models, including those involved in NMME, typically overestimate eastern Pacific warming during central Pacific El Niño events, which can affect precipitation predictions regions that are influenced by teleconnections, such as the southeast US. Land and atmosphere initialization, and the minimization of errors in these initial states, shows moderate improvement in skill, expected for the first seasonal lead. Finally, ocean-atmosphere coupling, in the context of this experiment design and in relation to prescribed SST versus fully coupled hindcasts, is a comparatively weak contribution to prediction skill and predictability.
