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Emma Ferranti, Lee Chapman, Caroline Lowe, Steve McCulloch, David Jaroszweski, and Andrew Quinn

lines, and delays to track maintenance. The databases are also used for internal analyses and research undertaken by Network Rail (e.g., Network Rail 2014a , 2015 ). In this study, the descriptions of individual faults and incidents in the FMS database (2006–13) were searched using an algorithm specifically designed to identify failures or incidents related to heat. The algorithm searched for key words and phrases related to heat, such as buckle, temp, expansion, hot, thermal, and so on. The

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Ronald L. Holle

Abstract

There is a major difference in population-weighted lightning fatality rates between the lower fatality rates in developed countries and the higher fatality rates in developing countries. The large decrease in annual rates of population-weighted lightning fatalities in the United States is described over the last century. A similar large reduction in lightning fatality rates has occurred during recent years in Australia, Canada, Japan, and western Europe, where there has also been a change from a mainly rural agricultural society to a primarily urban society. An important accompanying aspect of the lower casualty rates has been the widespread availability of lightning-safe large buildings and fully enclosed metal-topped vehicles, as well as much greater awareness of the lightning threat, better medical treatment, and availability of real-time lightning information. However, lightning exposure for many people in lesser-developed countries is similar to that of a century ago in developed countries. The number of people living in these areas may be increasing in number, so the number of people killed by lightning may be increasing globally due to these socioeconomic factors. It can be difficult to locate national lightning fatality data because of their mainly obscure publication sources. The present paper synthesizes lightning fatality data from 23 published national-scale studies during periods ending in 1979 and later, and maps these fatality rates per million by continent.

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Marius J. Paulikas, Thomas W. Schmidlin, and Timothy P. Marshall

Abstract

Two independent datasets (total n = 959) of tornado-stricken passenger vehicles collected from 12 tornado events over a 15-yr time span are combined and tested to determine whether vehicle movement and/or upset are consistent at various wind speed intensities. Impacted vehicles are classified into three categories of upset motions (no movement, lateral shifting, rolling and lofting motions) for each wind intensity category of the Fujita and Enhanced Fujita scales. Vehicles observed by Schmidlin exposed to F1 and F2 winds are statistically assessed to determine if upset distribution values are consistent with those assessed by Marshall at these respective wind speeds; this same approach is subsequently conducted for vehicles at F3/EF3 and F4/EF4 winds. No statistical differences are found between the two sets of field survey data, which are therefore considered to be of the same population. Passenger vehicles are currently not utilized as damage indicators for rating tornado wind intensities, although the results of this study suggest that only 10% of vehicles are typically shifted at EF0 wind speeds, 36% are displaced at EF1 and EF2 winds (5% are rolled or lofted), 63% are displaced at EF3 and EF4 winds (15% are rolled and lofted), and all vehicles exhibit some form of movement or upset at the EF5 wind speed. The results of this study may potentially serve as a basis for providing better tornado safety protocols, designing safer vehicles and infrastructure, and estimating tornado wind speeds where few EF-scale damage indicators are available.

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J. D. Tamerius, X. Zhou, R. Mantilla, and T. Greenfield-Huitt

Abstract

Numerous studies have shown that precipitation has a significant impact on motor vehicle crashes. Hourly weather radar data with a 4-km resolution and over 600 000 crashes from 2002 to 2012 in Iowa are used to assess the effects of precipitation on motor vehicle crashes. Using a matched pairs analysis, this study finds that the relative accident risk (RAR) across the state during the study period was 1.69 [1.66, 1.71]. However, RAR increased to as high as 3.7 [3.6, 4.0] and as low as 1.1 [1.0, 1.2] for frozen and liquid precipitation types, respectively. RAR also varied significantly by hour of the day, with RAR near 2 in the late afternoon and 1.3 during the early morning hours, suggesting an interaction effect between precipitation and traffic volume and/or density on crash risk. The study also shows that interstates and major highways tend to have higher RAR than smaller roads, and it was able to identify locations that are particularly sensitive to precipitation with regard to crashes. This study can be used to inform future studies on the effects of weather and climate change on crashes.

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Daniel S. Wilks and Kenneth A. Horowitz

climatological analyses, and the adaptive control algorithm that allows fair, risk-based pricing outside of the conventional bilateral market paradigm. Section 3 illustrates the operation of this pricing algorithm and its probability convergence in a simplified and idealized setting. Section 4 describes the simulation of a hypothetical market for the 2004 Atlantic hurricane season, through the landfall of Hurricane Charley. Section 5 summarizes and provides some concluding perspectives. A companion

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Scott Greene, Laurence S. Kalkstein, David M. Mills, and Jason Samenow

+ categories with a mean daily standardized mortality difference greater than 0 are categorized as EHE days. Once each day during the summer period is assigned to an airmass category, a mortality algorithm is developed that relates the variation in standardized mortality on all EHE days within a city to meteorological and environmental variables. The meteorological variables considered during the algorithm development include the following: maximum and minimum air temperature and maximum and minimum

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Robert J. Meyer, Michael Horowitz, Daniel S. Wilks, and Kenneth A. Horowitz

each market participant. Unlike traditional weather derivatives, market participants need not find a willing counterparty to take the opposite side of the contract. HuRLO prices in the primary market are based on an adaptive control algorithm (Bequillard 2013, manuscript submitted to Int. J. Theor. Appl. Finance ; Horowitz et al. 2013 ; Part I ) that is a new variant of the Robbins–Monro stochastic approximation algorithm ( Kushner and Yin 2003 ). These prices are proportional to probabilities

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James B. Elsner, Emily Ryan, and Georgianna Strode

; Ashley and Strader 2016 ). The regression coefficients multiplied by the corresponding annual exposure rate indicates an annual expected loss of $48 million. More relevant for insurance is the possibility of a big loss. We estimate the annual probable maximum loss (PML) as the value of the largest loss that could occur. Results from a Monte Carlo algorithm that randomly permutes the historical tornado paths indicate a 1% chance that the annual loss will exceed $430 million and a 0.1% chance that it

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Tanya M. Brown, William H. Pogorzelski, and Ian M. Giammanco

. (b) Composite MESH on 24 May 2011. Data courtesy NSSL Experimental On-Demand System. Radar-derived quantities have been used for hail detection to guide poststorm assessments and claims activities for many years. These tools rely on an underlying assumption that a relationship between horizontal reflectivity ( Z h ) and hail size exists and is statistically significant. The original WSR-88D hail detection algorithm was developed to indicate whether or not a storm sampled by operational radar was

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G. B. Raga, M. G. de la Parra, and Beata Kucienska

thousands of kilometers. WWLLN originated in New Zealand and Australia almost 15 years ago and it is mostly based at research centers and universities worldwide ( Dowden et al. 2008 ). As of October 2012, WWLLN included 68 sites distributed globally ( Virts et al. 2013 ). WWLLN detects the middle part of the VLF band, exclusively uses propagation in the channel between the surface and the ionosphere to limit lightning location errors, and applies a time of group arrival algorithm ( Dowden et al. 2002

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