Download or read book Statistical dynamical Forecasting of Tropical Cyclogenesis in the North Atlantic at Intraseasonal Lead Times written by Chad S. Raynak and published by . This book was released on 2009 with total page 71 pages. Available in PDF, EPUB and Kindle. Book excerpt: We have created a combined statistical-dynamical model to predict the probability of tropical cyclone (TC) formation at daily, 2.5°̊ horizontal resolution in the North Atlantic (NA) at intraseasonal lead times. Based on prior research and our own analyses, we chose five large scale environmental factors (LSEFs) to represent favorable environments for TC formation. The LSEFs include: 850 mb relative vorticity, sea surface temperature, vertical wind shear, Coriolis, and 200 mb divergence. We used logistic regression to create a statistical model that depicts the probability for TC formation based on these LSEFs. Through verification of zero lead hindcasts, we determined that our regression model performs better than climatology. For example, these hindcasts had a Brier skill score of 0.04 and a relative operating characteristic skill score of 0.72. We then forced our regression model with LSEF fields from the NCEP Climate Forecast System to produce non-zero lead hindcasts and forecasts. We conducted a series of case studies to evaluate and study the predictive skill of our regression model, with the results showing that our model produces promising results at intraseasonal lead times.
Download or read book A Statistical dynamical Approach to Intraseasonal Prediction of Tropical Cyclogenesis in the Western North Pacific written by Bryan D. Mundhenk and published by . This book was released on 2009 with total page 107 pages. Available in PDF, EPUB and Kindle. Book excerpt: We have developed a combined statistical-dynamical prediction scheme to predict the probability of tropical cyclone (TC) formation at daily, 2.5° horizontal resolution across the western North Pacific at intraseasonal lead times. Through examination of previous research and our own analysis, we chose five variables to represent the favorability of the climate system to support tropical cyclogenesis. These so-called large-scale environmental factors (LSEFs) include: low-level relative vorticity, sea surface temperature, vertical wind shear, Coriolis, and upper-level divergence. Logistic regression was employed to generate a statistical model representing the probability of TC formation at every grid point based on these LSEFs. Thorough verification of zero-lead hindcasts reveals this model displays skill and potential value for risk adverse customers. In particular, these hindcasts had a positive Brier skill score of 0.03 and a skillful relative operating characteristic skill score of 0.68. The fully coupled, one-tier NCEP Climate Forecast System was used as the dynamical model with which to forecast the LSEFs and, in turn, force the regression model. A series of individual TC case studies were conducted to demonstrate the predictive potential, at intraseasonal leads, of our statistical-dynamical method. Lastly, we investigated the applicability of intraseasonal forecasts to military planning.
Download or read book Prediction of North Atlantic Tropical Cyclone Activity and Rainfall written by Beda Nidhi Luitel and published by . This book was released on 2016 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt: Among natural disasters affecting the United States, North Atlantic tropical cyclones (TCs) and hurricanes are responsible for the highest economic losses and are one of the main causes of fatalities. Although we cannot prevent these storms from occurring, skillful seasonal predictions of the North Atlantic TC activity and associated impacts can provide basic information critical to our improved preparedness. Unfortunately, it is not yet possible to predict heavy rainfall and flooding associated with these storms several months in advance, and the lead time is limited to few days at the most. On the other hand, overall North Atlantic TC activity can be potentially predicted with a six- to nine-month lead time. This thesis focuses on the evaluation of the skill in predicting basin-wide North Atlantic TC activity with a long lead time and rainfall with a short lead time. For the seasonal forecast of TC activity, we develop statistical-dynamical forecasting systems for different quantities related to the frequency and intensity of North Atlantic TCs using only tropical Atlantic and tropical mean sea surface temperatures (SSTs) as covariates. Our results show that skillful predictions of North Atlantic TC activity are possible starting from November for a TC season that peaks in the August-October months. The short term forecasting of rainfall associated with TC activity is based on five numerical weather prediction (NWP) models. Our analyses focused on 15 North Atlantic TCs that made landfall along the U.S. coast over the period of 2007-2012. The skill of the NWP models is quantified by visual examination of the distribution of the errors for the different lead-times, and numerical examination of the first three moments of the error distribution. Based on our results, we conclude that the NWP models can provide skillful forecasts of TC rainfall with lead times up to 48 hours, without a consistently best or worst NWP model.
Download or read book Sub seasonal to Seasonal Prediction written by Andrew Robertson and published by Elsevier. This book was released on 2018-10-24 with total page 0 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.
Download or read book The Cryosphere and North Atlantic Tropical Cyclone Activity written by Johannes Mack and published by . This book was released on 2013 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: The components of the northern hemisphere cryosphere and their relationship to Atlantic tropical cyclone activity are investigated in this study. Multiple ordinary least-squares regression with a stepwise selection procedure is used to develop a new statistical forecasting scheme for 13 seasonal tropical cyclone parameters at four lead times for the period 1980-2010. Sea ice area and sea ice extent in 10 geographic regions, snow cover extent in three geographic regions and five indices reflecting major modes of climate variability were analyzed as possible predictors. Three model groups, based on predictors, were constructed and evaluated: 1) only climate mode predictors, 2) only cryosphere predictors, and 3) both cryosphere and climate mode predictors. Models using only climate mode predictors showed poor predictability of the tropical cyclone parameters across all four lead times while the models using only cryosphere predictors and those using both sets of predictors showed improved predictability. Baffin Bay and Hudson Bay sea ice area were found to be the most significant predictors, exhibiting an inverse relationship with overall tropical cyclone activity. The developed models were also compared to current operational statistical models of tropical cyclone activity. While the operational models were generally more skillful, June hindcasts of major hurricanes outperformed the operational models by as much as 20%.
Download or read book A Statistical Model for the Prediction of Western North Pacific Tropical Cyclone Motion WPCLPR written by Xu Yiming and published by . This book was released on 1985 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Climate Variability and Tropical Cyclone Activity written by Pao-Shin Chu and published by Cambridge University Press. This book was released on 2022-03-10 with total page 321 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a comprehensive summary of research on tropical cyclone variability at various time scales, from intraseasonal and interannual to interdecadal and centennial. It covers the fundamental theory, statistics and numerical modelling techniques used when considering climate variability in relation to tropical cyclone activity. Major climate oscillations including the Madden-Julian, El Niño, Atlantic Meridional Mode, and Pacific Decadal oscillations are covered, and their impacts on tropical cyclone activity in the Pacific and Atlantic oceans are discussed. Hurricane landfalls in the United States, Caribbean and East Asia are also considered. Climate models and numerical simulations are used to show how prediction models of tropical cyclones are developed, while looking to the future, particular attention is paid to predicting how tropical cyclones will change in response to increased concentrations of greenhouse gases. This book ideal for researchers and practitioners in atmospheric science, climatology, oceanography and civil and environmental engineering.
Download or read book Predictability and Prediction of Tropical Cyclones on Daily to Interannual Time Scales written by James Ian Belanger and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The spatial and temporal complexity of tropical cyclones (TCs) raises a number of scientific questions regarding their genesis, movement, intensification, and variability. In this dissertation, the principal goal is to determine the current state of predictability for each of these processes. To quantify the current extent of tropical cyclone predictability, we assess probabilistic forecasts from the most advanced global numerical weather prediction system to date, the ECMWF Variable Resolution Ensemble Prediction System (VarEPS). Using a new false alarm clustering technique to maximize the utility of the VarEPS, the ensemble system is shown to provide well-calibrated probabilistic forecasts for TC genesis through a lead-time of one week, and pregenesis track forecasts with similar skill compared to the VarEPS's postgenesis track forecasts. To quantify the predictability of TCs on intraseasonal time scales, forecasts from the ECMWF Monthly Forecast System (ECMFS) are examined for the North Atlantic Ocean. From this assessment, dynamically based forecasts from the ECMFS provide forecast skill exceeding climatology out to weeks three and four for portions of the southern Gulf of Mexico, western Caribbean and the Main Development Region. Forecast skill in these regions is traced to the model's ability to capture correctly the variability in deep-layer vertical wind shear, the relative frequency of easterly waves moving through these regions, and the intraseasonal modulation of the Madden-Julian Oscillation. :On interannual time scales, the predictability of TCs is examined by considering their relationship with tropical Atlantic easterly waves. First, a set of easterly wave climatologies for the CFS-R, ERA-Interim, ERA-40, and NCEP/NCAR Reanalysis are developed using a new easterly wave-tracking algorithm. From the reanalysis-derived climatologies, a moderately positive and statistically significant relationship is seen with tropical Atlantic TCs. In relation to large-scale climate modes, the Atlantic Multidecadal Oscillation (AMO) and Atlantic Meridional Mode (AMM) exhibit the strongest positive covariability with Atlantic easterly wave frequency. Besides changes in the number of easterly waves, the intensification efficiency of easterly waves has also been evaluated. These findings offer a plausible physical explanation for the recent increase in the number of NATL TCs, as it has been concomitant with an increasing trend in both the number of tropical Atlantic easterly waves and intensification efficiency. :The last component of this dissertation examines how the historical variability in U.S. landfalling TCs has impacted the annual TC tornado record. To reconcile the inhomogeneous, historical tornado record, two statistical tornado models, developed from a set of a priori predictors for TC tornado formation, are used to reconstruct the TC tornado climatology. While the synthetic TC tornado record reflects decadal scale variations in association with the AMO, a comparison of the current warm phase of the AMO with the previous warm phase period shows that the median number of tornadoes per Gulf TC landfall has significantly increased. This change likely reflects the increase in median TC size (by 35%) of Gulf landfalling TCs along with an increased frequency of large TCs at landfall.
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 2007-06-10 with total page 477 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first comprehensive review of intra-seasonal variability (ISV); the contents are balanced between observation, theory and modeling. Starting with an overview of ISV and historical observations, the book addresses the coupling between ocean and atmosphere, and the worldwide role of ISV in monsoon variability. Also considered are the connections between oscillations like the Madden, Julian and El Nino/Southern and short-term climate.
Download or read book World Weather Watch written by World Meteorological Organization and published by World Meteorological Organization. This book was released on 1979 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Statistical Forecasts of Tropical Cyclone Intensity for the North Atlantic Basin written by Brian R. Jarvinen and published by . This book was released on 1979 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Climatology of 24 hour North Atlantic Tropical Cyclone Movements written by George W. Cry and published by . This book was released on 1961 with total page 936 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Global Tropical Cyclogenesis written by E.A. Sharkov and published by Springer Science & Business Media. This book was released on 2001-04-18 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tropical cyclones are the most impressive and best phenomenon of the tropics, and this book fills a need for a thorough detailed book on the subject, concentrating on the remote sensing results on both initial and mature forms of tropical cyclones. It provides a comprehensive description of the physical, geophysical and meteorological foundations of global tropical cyclogenesis. The author emphasises the physical aspects necessary to judge the possibilities and limitations of monitoring mitigation methods, and includes numerous applications and illustrations from up-to-date airborne and satellite experiments.
Download or read book Tropical Cyclones of the North Atlantic Ocean written by George W. Cry and published by . This book was released on 1965 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advanced Numerical Modeling and Data Assimilation Techniques for Tropical Cyclone Predictions written by U.C. Mohanty and published by Springer. This book was released on 2016-11-21 with total page 762 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book deals primarily with monitoring, prediction and understanding of Tropical Cyclones (TCs). It was envisioned to serve as a teaching and reference resource at universities and academic institutions for researchers and post-graduate students. It has been designed to provide a broad outlook on recent advances in observations, assimilation and modeling of TCs with detailed and advanced information on genesis, intensification, movement and storm surge prediction. Specifically, it focuses on (i) state-of-the-art observations for advancing TC research, (ii) advances in numerical weather prediction for TCs, (iii) advanced assimilation and vortex initialization techniques, (iv) ocean coupling, (v) current capabilities to predict TCs, and (vi) advanced research in physical and dynamical processes in TCs. The chapters in the book are authored by leading international experts from academic, research and operational environments. The book is also expected to stimulate critical thinking for cyclone forecasters and researchers, managers, policy makers, and graduate and post-graduate students to carry out future research in the field of TCs.
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 NUMERICAL STATISTICAL FORECASTS OF TROPICAL CYCLONE TRACKS BY THE MOHATT SCHEME WITH APPLICATION TO THE NORTH ATLANTIC AREA written by R.J. Renard and published by . This book was released on 1972 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt:
