scholarly journals Influence of local and large-scale weather events and timing of breeding on tropical roseate tern reproductive parameters

2002 ◽  
Vol 243 ◽  
pp. 271-279 ◽  
Author(s):  
JA Ramos ◽  
AM Maul ◽  
V Ayrton ◽  
I Bullock ◽  
J Hunter ◽  
...  
Author(s):  
Andy H. Wong ◽  
Tae J. Kwon

Winter driving conditions pose a real hazard to road users with increased chance of collisions during inclement weather events. As such, road authorities strive to service the hazardous roads or collision hot spots by increasing road safety, mobility, and accessibility. One measure of a hot spot would be winter collision statistics. Using the ratio of winter collisions (WC) to all collisions, roads that show a high ratio of WC should be given a high priority for further diagnosis and countermeasure selection. This study presents a unique methodological framework that is built on one of the least explored yet most powerful geostatistical techniques, namely, regression kriging (RK). Unlike other variants of kriging, RK uses auxiliary variables to gain a deeper understanding of contributing factors while also utilizing the spatial autocorrelation structure for predicting WC ratios. The applicability and validity of RK for a large-scale hot spot analysis is evaluated using the northeast quarter of the State of Iowa, spanning five winter seasons from 2013/14 to 2017/18. The findings of the case study assessed via three different statistical measures (mean squared error, root mean square error, and root mean squared standardized error) suggest that RK is very effective for modeling WC ratios, thereby further supporting its robustness and feasibility for a statewide implementation.


2016 ◽  
Vol 33 (4) ◽  
pp. 621-634 ◽  
Author(s):  
Jingyin Tang ◽  
Corene J. Matyas

AbstractThe creation of a 3D mosaic is often the first step when using the high-spatial- and temporal-resolution data produced by ground-based radars. Efficient yet accurate methods are needed to mosaic data from dozens of radar to better understand the precipitation processes in synoptic-scale systems such as tropical cyclones. Research-grade radar mosaic methods of analyzing historical weather events should utilize data from both sides of a moving temporal window and process them in a flexible data architecture that is not available in most stand-alone software tools or real-time systems. Thus, these historical analyses require a different strategy for optimizing flexibility and scalability by removing time constraints from the design. This paper presents a MapReduce-based playback framework using Apache Spark’s computational engine to interpolate large volumes of radar reflectivity and velocity data onto 3D grids. Designed as being friendly to use on a high-performance computing cluster, these methods may also be executed on a low-end configured machine. A protocol is designed to enable interoperability with GIS and spatial analysis functions in this framework. Open-source software is utilized to enhance radar usability in the nonspecialist community. Case studies during a tropical cyclone landfall shows this framework’s capability of efficiently creating a large-scale high-resolution 3D radar mosaic with the integration of GIS functions for spatial analysis.


2021 ◽  
Author(s):  
Waqar Ul Hassan ◽  
Munir Ahmad Nayak

<p>Compound weather events arise from combination of multiple climatic drivers or hazards and often result in disastrous socio-economic impacts. Compound drought and heatwave (CDHE) events have received considerable attention in recent years, but limited attention is given towards the understanding of feedback relationships between droughts and heatwaves at global hotspots of the compound events. Here, we identify the potential hotspots of extreme compound drought and heatwaves (ECDH) over the globe using standardized precipitation index (SPI) and Excess heat factor (EHF) as metrics for droughts and heatwaves, respectively. Besides the well know positive feedback between droughts and heatwaves, i.e., heatwaves amplify droughts and vice-versa, we hypothesize and test the possibility of negative feedback at distinct hotspots where heatwaves tend to abate droughts. Multiple hotspots were identified with positive and negative feedbacks among drought and heatwave intensities, supporting our hypothesis. We also analyzed the role of different local and large-scale global drivers (such as El-Niño Southern Oscillation) on the feedbacks at the hotspots. Our analysis has implications in predicting extreme compound droughts and heatwaves and provides new insights that will foster further research in this direction.</p>


Author(s):  
Joseph J. Barsugli ◽  
Jeffrey S. Whitaker ◽  
Andrew F. Loughe ◽  
Prashant D. Sardeshmukh ◽  
Zoltan Toth
Keyword(s):  
El Niño ◽  
El Nino ◽  

2014 ◽  
Vol 9 (sp) ◽  
pp. 699-708 ◽  
Author(s):  
Lihui Wu ◽  
◽  
Haruo Hayashi ◽  

The purpose of this study is to explore the impact of disasters on international tourism demand for Japan by applying Autoregressive Integrated Moving Average (ARIMA) intervention models that focus on evaluating change patterns and the duration of effects by observing variations in parameters. Japan suffered a variety of disasters, especially natural disasters due to its geographical location, so we have divided these disasters into three types: geological disasters, extreme weather events and “others” such as terrorist attacks, infectious diseases, and economic crises. Based on the principle of preparing for the worst, we selected 4 cases for each disaster type, for 12 in all. Results suggest that (1) large-scale disasters such as great earthquakes impacted negatively on inbound tourism demand for Japan; (2) not all disasters resulted in an abrupt drop in inbound tourist arrivals, extreme weather events, for example, did not decrease inbound tourism demand significantly; (3) impact caused by disasters was temporary.


2020 ◽  
Vol 21 (12) ◽  
pp. 2907-2921
Author(s):  
Allison E. Goodwell

AbstractThe spatial and temporal ordering of precipitation occurrence impacts ecosystems, streamflow, and water availability. For example, both large-scale climate patterns and local landscapes drive weather events, and the typical speeds and directions of these events moving across a basin dictate the timing of flows at its outlet. We address the predictability of precipitation occurrence at a given location, based on the knowledge of past precipitation at surrounding locations. We identify “dominant directions of precipitation influence” across the continental United States based on a gridded daily dataset. Specifically, we apply information theory–based measures that characterize dominant directions and strengths of spatial and temporal precipitation dependencies. On a national average, this dominant direction agrees with the prevalent direction of weather movement from west to east across the country, but regional differences reflect topographic divides, precipitation gradients, and different climatic drivers of precipitation. Trends in these information relationships and their correlations with climate indices over the past 70 years also show seasonal and spatial divides. This study expands upon a framework of information-based predictability to answer questions about spatial connectivity in addition to temporal persistence. The methods presented here are generally useful to understand many aspects of weather and climate variability.


2017 ◽  
Author(s):  
Michał Bogdziewicz ◽  
Michael A. Steele ◽  
Shealyn Marino ◽  
Elizabeth E. Crone

Highly variable, synchronized seed production, called masting, is a widespread reproductive strategy in plants. Resource dynamics, pollination success, and, as described here, environmental veto, are possible proximate mechanisms of masting. We extended the resource budget model of masting with correlated and uncorrelated reproductive failure, and ran this model across its parameters space. Next, we parametrized the model based on a 16-year seed production data for red (Quercus rubra) and white (Q. alba) oaks. Simulations showed that resource dynamics and reproduction failure produce masting even in the absence of pollen coupling. In concordance, in both species, among-year variation in resource gain and correlated reproductive failure were necessary and sufficient to produce masting. Environmental variation is a form of reproduction failure caused by environmental veto that may drive large-scale synchronization without density-dependent pollen limitation. Reproductive-inhibiting weather events are prevalent in ecosystems, suggesting that these described mechanisms likely operate in many masting systems.


Author(s):  
Hengfang Deng ◽  
Daniel P. Aldrich ◽  
Michael M. Danziger ◽  
Jianxi Gao ◽  
Nolan E. Phillips ◽  
...  

AbstractMajor disasters such as extreme weather events can magnify and exacerbate pre-existing social disparities, with disadvantaged populations bearing disproportionate costs. Despite the implications for equity and emergency planning, we lack a quantitative understanding of how these social fault lines translate to different behaviours in large-scale emergency contexts. Here we investigate this problem in the context of Hurricane Harvey, using over 30 million anonymized GPS records from over 150,000 opted-in users in the Greater Houston Area to quantify patterns of disaster-inflicted relocation activities before, during, and after the shock. We show that evacuation distance is highly homogenous across individuals from different types of neighbourhoods classified by race and wealth, obeying a truncated power-law distribution. Yet here the similarities end: we find that both race and wealth strongly impact evacuation patterns, with disadvantaged minority populations less likely to evacuate than wealthier white residents. Finally, there are considerable discrepancies in terms of departure and return times by race and wealth, with strong social cohesion among evacuees from advantaged neighbourhoods in their destination choices. These empirical findings bring new insights into mobility and evacuations, providing policy recommendations for residents, decision-makers, and disaster managers alike.


2021 ◽  
Author(s):  
◽  
Ralph Peter Titmuss

<p>As a result of climate change, extreme weather events are becoming more common around the world. Coupled with the ever-present threat of sea level rise that coastal cities face there is a potential for far more severe weather events to occur. This thesis will seek to understand how an existing city can adapt to a more hostile environment, and how in the event of an extreme weather occurrence it maintains its function. There is an urgent need to understand how a city can respond when faced with these situations. Previous extreme weather events, Katrina, the Indian Ocean tsunami, and extreme flooding around the world, highlight the danger of a lack of preparedness and resilience found in most cities.  The purpose of this thesis is to understand how the concept of a core shelter, as a way to address the threats of extreme weather events, can be applied to a well-established urban context, Wellington NZ. A core shelter is a structure that in the event of a large-scale disaster, protects its users, and post-disaster still reaches permanent housing standards without being deemed to be a permanent dwelling. It will also look at whether it is possible to create areas in an existing city that can be considered “safe havens” in the event of an extreme natural incident.  This thesis outlines the need for these shelters by identifying the potential threats of climate change in a Wellington context, and by understanding the vulnerability of Wellington’s current building stock. It reaches a conclusion that through the implementation of core shelters in Wellington NZ, resilience will be improved, disaster response efforts will be aided, and destruction arising from extreme weather events will be reduced. In addition, it identifies the areas of Wellington that are deemed to be of higher risk in a disaster or extreme weather event, analyses an existing building’s potential to become a community resilience/core shelter, and proposes a custom building that could be built on Leeds St and Ghuznee St.</p>


Atmosphere ◽  
2019 ◽  
Vol 10 (12) ◽  
pp. 793 ◽  
Author(s):  
Yu-Tang Chien ◽  
S.-Y. Simon Wang ◽  
Yoshimitsu Chikamoto ◽  
Steve L. Voelker ◽  
Jonathan D. D. Meyer ◽  
...  

In recent years, a pair of large-scale circulation patterns consisting of an anomalous ridge over northwestern North America and trough over northeastern North America was found to accompany extreme winter weather events such as the 2013–2015 California drought and eastern U.S. cold outbreaks. Referred to as the North American winter dipole (NAWD), previous studies have found both a marked natural variability and a warming-induced amplification trend in the NAWD. In this study, we utilized multiple global reanalysis datasets and existing climate model simulations to examine the variability of the winter planetary wave patterns over North America and to better understand how it is likely to change in the future. We compared between pre- and post-1980 periods to identify changes to the circulation variations based on empirical analysis. It was found that the leading pattern of the winter planetary waves has changed, from the Pacific–North America (PNA) mode to a spatially shifted mode such as NAWD. Further, the potential influence of global warming on NAWD was examined using multiple climate model simulations.


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