hurricanes

飓风
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  • 文章类型: Journal Article
    气候变化对珊瑚礁构成了生存威胁。温暖和酸性更强的海洋削弱了珊瑚生态系统,并增加了飓风的强度。飓风期间的风浪流相互作用极大地改变了海洋环流模式,因此有可能影响珊瑚幼虫和珊瑚疾病病原体的扩散。这里,我们模拟了飓风Irma(2017年9月)对佛罗里达珊瑚礁的珊瑚幼虫和石质珊瑚组织损失病(SCTLD)连通性的影响。我们将高分辨率的沿海海洋环流和波浪模型相结合,以模拟虚拟珊瑚幼虫和疾病病原体在数千个珊瑚礁之间的扩散。虽然是一个简短的事件,我们的结果表明,飓风Irma的通过大大增加了长途交换的可能性,同时减少了幼虫的供应。它创造了新的联系,可以促进珊瑚的复原力,但也可能加速SCTLD的传播大约一个月。随着它们变得越来越强烈,飓风的双刃效应将越来越明显,有助于增加运输模式的可变性和加速珊瑚礁生态系统内的变化速度。
    Climate change poses an existential threat to coral reefs. A warmer and more acidic ocean weakens coral ecosystems and increases the intensity of hurricanes. The wind-wave-current interactions during a hurricane deeply change the ocean circulation patterns and hence potentially affect the dispersal of coral larvae and coral disease agents. Here, we modeled the impact of major hurricane Irma (September 2017) on coral larval and stony coral tissue loss disease (SCTLD) connectivity in Florida\'s Coral Reef. We coupled high-resolution coastal ocean circulation and wave models to simulate the dispersal of virtual coral larvae and disease agents between thousands of reefs. While being a brief event, our results suggest the passage of hurricane Irma strongly increased the probability of long-distance exchanges while reducing larval supply. It created new connections that could promote coral resilience but also probably accelerated the spread of SCTLD by about a month. As they become more intense, hurricanes\' double-edged effect will become increasingly pronounced, contributing to increased variability in transport patterns and an accelerated rate of change within coral reef ecosystems.
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  • 文章类型: Journal Article
    胎记导乐集体,在大新奥尔良地区提供导乐和哺乳服务的合作社,在两次第4类风暴后启动了应急响应:劳拉飓风(2020年)和伊达飓风(2021年)。回应包括启动免费的围产期和婴儿喂养紧急热线。这两次灾难都与路易斯安那州COVID-19感染的死灰复燃相吻合。
    这项研究的目的是了解在路易斯安那州飓风期间,紧急围产期和婴儿喂养热线如何支持婴儿和幼儿在紧急情况下喂养。
    这项研究使用了横截面,在母乳喂养率低的人群中进行回顾性定性设计。我们对劳拉飓风和艾达飓风的97个热线电话记录进行了内容分析,与哺乳支持提供者的焦点小组在任何一场风暴期间都为热线配备了人员(n=5),并采访了在飓风伊达(n=2)期间打电话的母亲。焦点小组和访谈持续了30分钟和60分钟,分别。使用专题分析技术分析成绩单。
    通话记录显示了婴儿的喂养需求(例如,乳腺炎,牛奶供应不足,relactation,和婴儿配方奶粉请求)和非婴儿喂养需求(例如,婴儿用品,围产期和婴儿护理转诊,庇护所信息)。在两次飓风期间,婴儿配方奶粉是最需要的供应。产妇参与者讨论了爱达飓风期间的家庭脆弱性。工作人员描述了在维持自身福祉的同时提供支持的培训和策略。
    提供免费的紧急热线服务是支持孕妇和产后患者及其家人寻求婴儿喂养建议的一种方式,用品,并在灾难发生后立即提供支持。
    UNASSIGNED: Birthmark Doula Collective, a cooperative that provides doula and lactation services in the Greater New Orleans area, mounted an emergency response after two Category 4 storms: Hurricane Laura (2020) and Hurricane Ida (2021). The response included activating a no-cost emergency perinatal and infant feeding hotline. Both disasters coincided with a resurgence of COVID-19 infections in Louisiana.
    UNASSIGNED: The aim of this study is to understand how an emergency perinatal and infant feeding hotline supported infant and young child feeding in emergencies during hurricanes in Louisiana.
    UNASSIGNED: This study used a cross-sectional, retrospective qualitative design in a population with low breastfeeding rates. We conducted a content analysis of 97 hotline call logs from Hurricanes Laura and Ida, focus groups with lactation support providers who staffed the hotline during either storm (n = 5), and interviews with mothers who called during Hurricane Ida (n = 2). Focus groups and interviews lasted 30 and 60 minutes, respectively. Transcripts were analyzed using thematic analysis techniques.
    UNASSIGNED: Call logs revealed infant feeding needs (e.g., mastitis, low milk supply, relactation, and infant formula requests) and non-infant feeding needs (e.g., infant supplies, perinatal and infant care referrals, shelter information). Infant formula was the most requested supply during both hurricanes. Maternal participants discussed family vulnerabilities during Hurricane Ida. Staff described training and strategies to provide support while maintaining their own well-being.
    UNASSIGNED: Providing a free emergency hotline service is one way to support pregnant and postpartum people and their families seeking infant feeding advice, supplies, and support in the immediate aftermath of a disaster.
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  • 文章类型: Journal Article
    目的:癌症患者是灾难期间和之后最脆弱的人群。我们评估了在飓风Irma和María之后,治疗中断对波多黎各妇科癌症妇女生存率的影响。
    方法:在2016年1月至2017年9月期间诊断的基于临床的女性样本中进行回顾性队列研究(n=112)。从诊断到2019年12月对妇女进行随访,以评估生命状况。进行Kaplan-Meier存活曲线和Cox比例风险模型。
    结果:平均年龄为56(±12.3)岁;子宫体(58.9%)是最常见的妇科癌症。主要治疗方法为手术(91.1%)和化疗(44.6%)。总的来说,75.9%的人在飓风之前接受治疗,16.1%的人在随访期间经历了治疗中断,8.9%的人在随访期间死亡。双变量分析中与治疗中断相关的因素包括年龄较小(≤55岁),患有区域性/远处疾病,并接受>1次癌症治疗(p<0.05)。粗略分析显示,中断治疗的女性死亡风险增加(HR:3.88,95%CI=1.09-13.77),调整年龄和癌症分期后持续存在(HR:2.49,95%CI=0.69-9.01)。
    结论:研究结果强调了飓风过后治疗中断对癌症生存率的不利影响,强调需要为这一弱势群体制定应急计划。
    OBJECTIVE: Cancer patients are among the most vulnerable populations during and after a disaster. We evaluated the impact of treatment interruption on the survival of women with gynecologic cancer in Puerto Rico following hurricanes Irma and María.
    METHODS: Retrospective cohort study among a clinic-based sample of women diagnosed between January 2016-September 2017 (n=112). Women were followed up from their diagnosis until December 2019, to assess vital status. Kaplan-Meier survival curves and Cox proportional hazards models were performed.
    RESULTS: Mean age was 56 (±12.3) years; corpus uteri (58.9%) was the most common gynecologic cancer. Predominant treatments were surgery (91.1%) and chemotherapy (44.6%). Overall, 75.9% were receiving treatment before the hurricanes, 16.1% experienced treatment interruptions and 8.9% died during the follow-up period. Factors associated with treatment interruption in bivariate analysis included younger age (≤55 years), having regional/distant disease, and receiving >1 cancer treatment (p<0.05). Crude analysis revealed an increased risk of death among women with treatment interruption (HR: 3.88, 95% CI=1.09-13.77), persisting after adjusting for age and cancer stage (HR: 2.49, 95% CI= 0.69-9.01).
    CONCLUSIONS: Findings underscore the detrimental impact of treatment interruption on cancer survival in the aftermath of hurricanes, emphasizing the need for emergency response plans for this vulnerable population.
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  • 文章类型: Journal Article
    基于自然的气候解决方案(NCS)被视为缓解气候变化的主要工具。特别是在能够储存和封存大量碳的森林地区。新英格兰是美国森林最茂密的地区之一(按土地面积计算,森林面积>75%)。森林碳是气候缓解政策的重要组成部分。大量罕见的干扰,比如飓风,是依靠森林碳来缓解气候变化的政策的不确定性和风险的主要来源,特别是预计气候变化会改变飓风的强度和程度。迄今为止,大多数关于干扰对森林碳储量影响的研究都集中在火灾上。这里,我们表明,该地区的单个飓风可以下降121至250MMTCO2e或地上森林总碳的4.6%-9.4%,远高于新英格兰森林每年封存的碳(16MMTCO2e年-1)。然而,飓风的排放不是瞬时的;减少的碳变成净排放需要大约19年,减少的碳排放的90%需要100年。使用HURRECON和EXPOS模型在一系列历史和预计风速下重建飓风,我们发现,飓风风速增加8%和16%会导致严重受损区域(广泛的树木死亡率)的范围增加10.7和24.8倍。风速的增加也导致了前所未有的地理变化,内陆和北部,进入森林茂密的地区,传统上受飓风影响较小。鉴于单个飓风可以排放相当于新英格兰森林封存的10年以上的碳,这些森林作为持久碳汇的地位是不确定的。对于依赖森林作为NCS的决策者来说,了解干扰对森林碳储量的风险是必要的。
    Nature-based climate solutions (NCS) are championed as a primary tool to mitigate climate change, especially in forested regions capable of storing and sequestering vast amounts of carbon. New England is one of the most heavily forested regions in the United States (>75% forested by land area), and forest carbon is a significant component of climate mitigation policies. Large infrequent disturbances, such as hurricanes, are a major source of uncertainty and risk for policies relying on forest carbon for climate mitigation, especially as climate change is projected to alter the intensity and extent of hurricanes. To date, most research into disturbance impacts on forest carbon stocks has focused on fire. Here, we show that a single hurricane in the region can down between 121 and 250 MMTCO2e or 4.6%-9.4% of the total aboveground forest carbon, much greater than the carbon sequestered annually by New England\'s forests (16 MMTCO2e year-1). However, emissions from hurricanes are not instantaneous; it takes approximately 19 years for downed carbon to become a net emission and 100 years for 90% of the downed carbon to be emitted. Reconstructing hurricanes with the HURRECON and EXPOS models across a range of historical and projected wind speeds, we find that an 8% and 16% increase in hurricane wind speeds leads to a 10.7- and 24.8-fold increase in the extent of high-severity damaged areas (widespread tree mortality). Increased wind speed also leads to unprecedented geographical shifts in damage, both inland and northward, into heavily forested regions traditionally less affected by hurricanes. Given that a single hurricane can emit the equivalent of 10+ years of carbon sequestered by forests in New England, the status of these forests as a durable carbon sink is uncertain. Understanding the risks to forest carbon stocks from disturbances is necessary for decision-makers relying on forests as a NCS.
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  • 文章类型: Journal Article
    背景:全球大多数婴儿推荐母乳喂养,特别是在自然灾害期间和之后,由于不卫生的条件和缺乏饮用水,不良后果的风险增加。材料与方法:使用波多黎各妊娠风险评估监测系统的2017-2019年数据,对2448名近期活产的受访者进行调查,我们根据婴儿出生月份和年份相对于飓风Irma和Maria发生的时间将受访者分为4个飓风暴露时间段:(1)飓风前;(2)急性飓风;(3)飓风后,早期恢复;和(4)术后,长期复苏。我们检查了分娩住院期间的产妇护理实践与3个月时的纯母乳喂养之间的关系,并按时间段进行了分层。我们还按时间段分别检查了每种产妇护理实践与纯母乳喂养之间的关联。结果:在急性飓风期间(调整后的患病率[aPR]:1.43,95%置信区间:1.09-1.87),在3个月时的纯母乳喂养高于飓风前时间段。支持性产妇护理实践与纯母乳喂养呈正相关,终止母乳喂养的危险因素和做法与纯母乳喂养呈负相关.第一个小时的母乳喂养(aPR范围:1.51-1.92)和同室(aPR范围:1.50-2.58)与所有时间段的纯母乳喂养呈正相关,除了飓风前的时间段。在所有时间段内,收到带有配方奶粉的礼品包装与纯母乳喂养(aPR范围:0.22-0.54)呈负相关。结论:分娩住院期间的产妇护理实践可能会影响母乳喂养行为,并可以在自然灾害期间和之后改善母乳喂养。在自然灾害期间和之后,可以进一步支持维持和改进这些做法的战略。
    Background: Breastfeeding is recommended globally for most infants, especially during and after natural disasters when risk of adverse outcomes increases because of unsanitary conditions and lack of potable water. Materials and Methods: Using 2017-2019 data from Puerto Rico\'s Pregnancy Risk Assessment Monitoring System for 2,448 respondents with a recent live birth, we classified respondents into 4 hurricane exposure time periods based on infant birth month and year relative to when Hurricanes Irma and Maria occurred: (1) prehurricane; (2) acute hurricane; (3) posthurricane, early recovery; and (4) posthurricane, long-term recovery. We examined the association between maternity care practices during delivery hospitalization and exclusive breastfeeding at 3 months overall and stratified by time period. We also examined the associations between each maternity care practice and exclusive breastfeeding separately by time period. Results: Exclusive breastfeeding at 3 months was higher during the acute hurricane time period (adjusted prevalence ratio [aPR]: 1.43, 95% confidence interval: 1.09-1.87) than the prehurricane time period. Supportive maternity care practices were positively associated with exclusively breastfeeding, and practices that are risk factors for discontinuing breastfeeding were negatively associated with exclusive breastfeeding. Breastfeeding in the first hour (aPR range: 1.51-1.92) and rooming-in (aPR range: 1.50-2.58) were positively associated with exclusive breastfeeding across all time periods, except the prehurricane time period. Receipt of a gift pack with formula was negatively associated with exclusive breastfeeding (aPR range: 0.22-0.54) across all time periods. Conclusions: Maternity care practices during delivery hospitalization may influence breastfeeding behaviors and can improve breastfeeding during and after natural disasters. Strategies to maintain and improve these practices can be further supported during and after natural disasters.
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  • 文章类型: Journal Article
    Swainson的莺(Limnothlypisswainsonii)的核心繁殖范围与北美东南部龙卷风频率极高的区域重叠。龙卷风在为这种全球罕见的莺和其他依赖干扰的物种创造繁殖栖息地方面的重要性在很大程度上被忽视了。本文估计了1988年至2014年记录了繁殖的240个县和教区的龙卷风频率(1950-2021年)和森林干扰。破坏性龙卷风(EF1-EF5)的频率在整个繁殖范围内变化了6倍,在墨西哥湾沿岸各州达到峰值。从德克萨斯州东部到阿拉巴马州的县经历了每1000平方公里5.4年的最低平均回报间隔,导致每世纪每1000平方公里约2477公顷的森林破坏。基于目前的林地覆盖。龙卷风在核心繁殖范围的北部和东部明显较少发生,大西洋沿海平原上的繁殖县的返回间隔增加到每1000平方公里9.1年,Ozark山脉每1000平方公里10.2年,阿巴拉契亚山脉每1000平方公里32.3年。从德克萨斯州东部到北卡罗来纳州的海岸线150公里范围内的育种县也受到西半球飓风频率最高的影响。飓风通常会造成巨大的森林破坏,但存档的气象和林业数据不足以估计育种县森林干扰的总体程度。然而,前人为时代龙卷风和飓风的综合影响可能足以产生对Swainson莺的繁殖生态至关重要的早期演替森林的动态镶嵌。为了确保这只稀有的莺的长期生存,建议制定栖息地管理计划,纳入灾难性风暴和人为活动产生的早期演替森林的遥感数据。
    The core breeding range of Swainson\'s warbler (Limnothlypis swainsonii) overlaps a zone of exceptionally high tornado frequency in southeastern North America. The importance of tornadoes in creating breeding habitat for this globally rare warbler and other disturbance-dependent species has been largely overlooked. This paper estimates tornado frequency (1950-2021) and forest disturbance in the 240 counties and parishes in which breeding was documented from 1988 to 2014. The frequency of destructive tornadoes (EF1-EF5) varied 6-fold across the breeding range with a peak in the Gulf Coast states. Counties from east Texas to Alabama experienced the lowest median return interval of 5.4 years per 1000 km2, resulting in approximately 2477 ha of forest damage per 1000 km2 per century, based on current forestland cover. Tornadoes were significantly less frequent north and east of the core breeding range, with return intervals increasing to 9.1 years per 1000 km2 for breeding counties on the Atlantic coastal plain, 10.2 years per 1000 km2 in the Ozark Mountains, and 32.3 years per 1000 km2 in the Appalachian Mountains. Breeding counties within 150 km of the coastline from east Texas to North Carolina are also subjected to the highest frequency of hurricanes in the Western Hemisphere. Hurricanes often cause massive forest damage but archived meteorological and forestry data are insufficient to estimate the aggregate extent of forest disturbance in breeding counties. Nevertheless, the combined impact of tornadoes and hurricanes in the pre-Anthropogenic era was likely sufficient to produce a dynamic mosaic of early-successional forest crucial for the breeding ecology of Swainson\'s warbler. To ensure the long-term survival of this rare warbler, it is advisable to develop habitat management plans that incorporate remote sensing data on early-successional forest generated by catastrophic storms as well as anthropogenic activities.
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  • 文章类型: Journal Article
    Central America and the Caribbean are regularly battered by megadroughts, heavy rainfall, heat waves, and tropical cyclones. Although 21st-century climate change is expected to increase the frequency, intensity, and duration of these extreme weather events (EWEs), their incidence in regional protected areas (PAs) remains poorly explored. We examined historical and projected EWEs across the region based on 32 metrics that describe distinct dimensions (i.e., intensity, duration, and frequency) of heat waves, cyclones, droughts, and rainfall and compared trends in PAs with trends in unprotected lands. From the early 21st century onward, exposure to EWEs increased across the region, and PAs were predicted to be more exposed to climate extremes than unprotected areas (as shown by autoregressive model coefficients at p < 0.05 significance level). This was particularly true for heat waves, which were projected to have a significantly higher average (tested by Wilcoxon tests at p < 0.01) intensity and duration, and tropical cyclones, which affected PAs more severely in carbon-intensive scenarios. PAs were also predicted to be significantly less exposed to droughts and heavy rainfall than unprotected areas (tested by Wilcoxon tests at p < 0.01). However, droughts that could threaten connectivity between PAs are increasingly common in this region. We estimated that approximately 65% of the study area will experience at least one drought episode that is more intense and longer lasting than previous droughts. Collectively, our results highlight that new conservation strategies adapted to threats associated with EWEs need to be tailored and implemented promptly. Unless urgent action is taken, significant damage may be inflicted on the unique biodiversity of the region.
    Ciclones, olas de calor, sequías y lluvias intensas son eventos comunes en Centroamérica y el Caribe, cuya frecuencia, intensidad y duración se espera aumente durante el siglo XXI a causa del cambio climático. Sin embargo, en la actualidad, se desconoce cuál será la incidencia de estos eventos meteorológicos extremos (EME) dentro de las áreas protegidas. En este estudio examinamos la exposición histórica y futura a los extremos climáticos y comparamos el grado de exposición dentro y fuera de las áreas protegidas de toda la región por medio de 32 métricas que describen distintas dimensiones (intensidad, duración y frecuencia) de las olas de calor, los ciclones, las sequías y las precipitaciones. Los resultados indican que a medida que aumente el número de EME, las áreas protegidas estarán más expuestas a los extremos climáticos que las áreas no protegidas. Esto es especialmente cierto en el caso de las olas de calor, que, según las proyecciones, tendrán una intensidad y una duración medias significativamente mayores, y de los ciclones tropicales, que afectarán más gravemente a las zonas protegidas en los escenarios intensivos en carbono. Nuestros resultados también indican que las zonas protegidas estarán significativamente menos expuestas a sequías o lluvias torrenciales que las zonas no protegidas. Sin embargo, las sequías que podrían amenazar la conectividad entre áreas protegidas son cada vez más frecuentes en esta región. Se estima que aproximadamente el 65% del área de estudio experimentará al menos un episodio de sequía más intenso y duradero que las sequías anteriores. En conjunto, nuestros resultados ponen de relieve la necesidad de diseñar y aplicar con prontitud nuevas estrategias de conservación adaptadas a las amenazas asociadas a los EWE. A menos que se tomen medidas urgentes, la biodiversidad única de la región podría sufrir daños considerables.
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  • 文章类型: Journal Article
    直立的分支海绵,比如花椰菜,为其他生物提供关键的三维栖息地,并帮助稳定珊瑚礁基质,但在暴风雨中极易破裂。破碎会增加海绵破碎,导致种群克隆性和近亲繁殖。相反,风暴可以为新的基因型通过幼虫招募进入种群提供机会,导致风暴频繁的地区遗传多样性更大。2017年美属维尔京群岛(USVI)连续发生了两次前所未有的5级飓风,这为评估珊瑚礁上新获得的基质的重新定殖是否是由于当地原因(例如,残留物的重新生长,碎片化,幼虫招募)或偏远(例如幼虫运输和移民)海绵基因型。我们从圣托马斯周围的四个珊瑚礁和圣克罗伊(USVI)的两个珊瑚礁中采样了成虫和幼虫。使用2bRAD协议,对所有样本进行单核苷酸多态性(SNPs)基因分型.结果表明,这些主要的风暴事件有利于海绵幼虫的募集,但并未增加草藻种群的遗传多样性。风暴后基质通过克隆性的重新定殖率低于预期(15%),而主要是由于通过当地幼虫招募有性繁殖(85%)。暴风雨确实增强了位于圣托马斯以南和圣克罗伊以北的珊瑚礁之间和内部的基因流。因此,海洋克隆物种种群,例如A.cauliformis,可能受益于飓风频率和强度的增加,以维持遗传多样性和打击近亲繁殖,增强加勒比海绵社区对极端风暴事件的抵御能力。
    Upright branching sponges, such as Aplysina cauliformis, provide critical three-dimensional habitat for other organisms and assist in stabilizing coral reef substrata, but are highly susceptible to breakage during storms. Breakage can increase sponge fragmentation, contributing to population clonality and inbreeding. Conversely, storms could provide opportunities for new genotypes to enter populations via larval recruitment, resulting in greater genetic diversity in locations with frequent storms. The unprecedented occurrence of two Category 5 hurricanes in close succession during 2017 in the U.S. Virgin Islands (USVI) provided a unique opportunity to evaluate whether recolonization of newly available substrata on coral reefs was due to local (e.g. re-growth of remnants, fragmentation, larval recruitment) or remote (e.g. larval transport and immigration) sponge genotypes. We sampled A. cauliformis adults and juveniles from four reefs around St. Thomas and two in St. Croix (USVI). Using a 2bRAD protocol, all samples were genotyped for single-nucleotide polymorphisms (SNPs). Results showed that these major storm events favoured sponge larval recruitment but did not increase the genetic diversity of A. cauliformis populations. Recolonization of substratum post-storms via clonality was lower (15%) than expected and instead was mainly due to sexual reproduction (85%) via local larval recruitment. Storms did enhance gene flow among and within reef sites located south of St. Thomas and north of St. Croix. Therefore, populations of clonal marine species with low pelagic dispersion, such as A. cauliformis, may benefit from increased frequency and magnitude of hurricanes for the maintenance of genetic diversity and to combat inbreeding, enhancing the resilience of Caribbean sponge communities to extreme storm events.
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  • 文章类型: Journal Article
    气候变化正在推动更高的沿海水位,和模型项目加速了未来的海平面上升和沿海风暴的加剧。气候变化与人为沿海变化相结合将推动全球沿海急剧变化。具有混合沉积物大小的复合海滩需要进行详细的研究,因为由于不同沉积物类型的不同传输阈值,这些海滩表现出复杂的动力学,以响应不断变化的流体动力学。这项研究使用了一种新颖的多方法方法来调查加拿大大西洋地区的复合砂卵石海滩,该海滩经历了缩短的季节性砂覆盖期。在重点关注的八个月内监测了水动力强迫和相关的形态动力学,同时,对基于卫星的视觉图像和重建的波浪数据进行了较长时间的分析。结果表明,年内波浪能变化驱动沙土动力学,夏季波浪能量减少,有利于短期沉积。在春末的波浪高度中发现了长期的积极趋势,这可能有助于缩短沙子覆盖期。季节动态被温带气旋菲奥娜淹没,它于2022年9月24日登陆,在海湾产生高达6.8米的显著波高,动员沉积物,和陡峭的卵石护堤。一种基于视觉图像的新索引方法使用与鹅卵石相比的相对发红来促进海滩沙子外观/消失的调查。最后,基于无人机的勘测产生了高分辨率的正交测量和基于激光雷达的高程测绘,并强调了Fiona期间侵蚀和沉积的明显长岸变化。海滩在<4个月内大部分恢复到风暴前的状况,这表明拟议的海滩营养活动可能只会暂时成功。显示沙子转化为卵石的长期结果表明,沙滩栖息地的丧失可能会增加,即使没有海岸线迁移或海平面上升驱动的沿海挤压。
    Climate change is driving higher coastal water levels, and models project accelerated future sea-level rise and coastal storm intensification. These dynamics paired with anthropogenic coastal alterations will drive drastic coastal change worldwide. Composite beaches with mixed sediment sizes warrant detailed study as these exhibit complex morphodynamics in response to changing hydrodynamics due to the distinct transport thresholds of different sediment types. This study uses a novel multi-method approach to investigate a composite sand-cobble beach in Atlantic Canada experiencing a shortening seasonal sand-covered period. Hydrodynamic forcing and associated beach changes were monitored over a focused eight-month period, while satellite-based visual imagery and reconstructed wave data were analyzed over longer periods. Results show that intra-annual wave energy changes drive sand dynamics, with reduced summer wave energy facilitating short-term deposition. Long-term positive trends were identified in late spring wave heights, which likely contribute to the shortening sand-covered period. Seasonal dynamics were overwhelmed by extratropical cyclone Fiona, which made landfall on September 24, 2022, generating significant wave heights up to 6.8 m in the bay, mobilizing sediment, and steepening cobble berms. A new index approach based on visual imagery facilitated the investigation of beach sand appearance/disappearance using the relative redness of sand compared to cobble. Finally, the UAV-based surveys yielded high-resolution orthomosaics and LiDAR-based elevation mapping, and highlighted pronounced longshore variability in erosion and deposition during Fiona. The beach mostly recovered to pre-storm conditions in <4 months, which indicates that proposed beach nourishment activities may only experience temporary success. The longer-term results showing a conversion of sand to cobble suggest that loss of sandy beach habitat is likely to increase, even without shoreline migration or coastal squeeze driven by sea-level rise.
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