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Barrier islands within sheltered environments are an important natural defense from severe storm impacts for coastal communities worldwide. Despite their importance, these fetch-limited barrier islands remain understudied and their ability to withstand and recover from storms is not well-understood. Here, we present a case study of Sugarloaf Island in North Carolina that demonstrates the operational use of openly accessible LiDAR and aerial imagery data to quantify synoptic habitat, shoreline, and volumetric change between 2014 and 2020, a period that encompasses four hurricanes and a winter storm event. During this time period, our results show: (1) an 11–13% decrease in marsh and shrub habitat, (2) an average landward shoreline migration of 2.9 m yr−1 and up to 5.2 m yr−1 in extreme areas, and (3) a net volume loss of approximately 9800 m3. The results of this study highlight the importance of storms as a driver of morphologic change on Sugarloaf Island and have implications for better understanding the resiliency of fetch-limited barrier islands to storms. This work helps to enhance prerestoration data availability and supports knowledge-based decision-making regarding habitat change, erosional issues, and the efficacy of nature-based solutions to increase the resiliency of a coastal community in North Carolina.

Catastrophic weather has significantly battered the U.S. Gulf Coast in recent years and exposed critical deficiencies in the resilience across communities and organizations. These deficiencies compel the devising of strategies to identify critical infrastructure components that require more attention with regard to building resilience. This article presents a holistic approach to assessing urban resilience by studying the coresilience of infrastructure networks. For this purpose, Tallahassee, Florida is used as a case study with a focus on both power and roadway networks and includes real-life disaster data from three extreme weather events that recently hit the study area. This article contributes to the coresilience concept through: 1) ­developing a geographical information system-based information-gathering approach to obtain an integrated infrastructure network and feed the causality models, 2) developing novel coresilience metrics to spatially identify and evaluate the high-risk locations, and 3) presenting a comprehensive case study and application of the developed approaches by using real-life data from three major storms that hit the study area.

Extreme wind events affect lake phytoplankton amongst others by deepening the mixed layer and increasing internal nutrient loading. Both increases and decreases of phytoplankton biomass after storms have been observed, but the precise mechanisms driving these responses remain poorly understood or quantified. In this study, we coupled a one-dimensional physical model to a biogeochemical model to investigate the factors regulating short-term phytoplankton responses to summer storms, now and under expected warmer future conditions. We simulated physical, chemical and biological dynamics in Lake Erken, Sweden, and found that wind storms could increase or decrease the phytoplankton concentration one week after the storm, depending on antecedent lake physical and chemical conditions. Storms had little effect on phytoplankton biomass if the mixed layer was deep prior to storm exposure. Higher incoming shortwave radiation and hypolimnetic nutrient concentration boosted growth, whereas higher surface water temperatures decreased phytoplankton concentration after storms. Medium-intensity wind speeds resulted in more phytoplankton biomass after storms than high-intensity wind. Simulations under a future climate scenario did not show marked differences in the way wind affects phytoplankton growth following storms. Our study shows that storm impacts on lake phytoplankton are complex and likely to vary as a function of local environmental conditions. Title in thesis list of papers:Drivers of phytoplankton responses to summer storms in a stratified lake: a modelling study

This dataset contains the results discussed in the journal article titled 'Storm sediment contribution to salt marsh accretion and expansion'.

Arboricultural research: unbiased and non-commercial research on tree assessment methods (breaking and uprooting). Analysis of existing methods. Research on how (palm)trees really break or uproot and their interaction with (wind) loads. Biomechanics of trees and palms.

In freshwater ecosystems, phosphorus (P) is often considered a growth-limiting nutrient. The use of fertilizers on agricultural fields has led to runoff-driven increases in P availability in streams, and the subsequent eutrophication of downstream ecosystems. Isolated storms and periodic streambed dredging are examples of two common disturbances that contribute dissolved and particulate P to agricultural streams, which can be quantified as soluble reactive P (SRP) using the molybdate-blue method on filtered water samples, or total P (TP) measured using digestions on unfiltered water reflecting all forms of P. While SRP is often considered an approximation of bioavailable P (BAP), research has shown that this is not always the case. Current methods used to estimate BAP do not account for the role of biology (e.g., NaOH extractions) or require specialized platforms (e.g., algal bioassays). Here, in addition to routine analysis of SRP and TP, we used a novel yeast-based bioassay with unfiltered sample water to estimate BAP concentrations during two storms (top 80% and > 95% flow quantiles), and downstream of a reach where management-associated dredging disturbed the streambed. We found that the BAP concentrations were often greater than SRP, suggesting that SRP is not fully representative of P bioavailability. The SRP concentrations were similarly elevated during the two storms, but remained consistently low during streambed disturbance. In contrast, turbidity and TP were elevated during all events. The BAP concentrations were significantly related to turbidity during all disturbance events, but with TP only during storms. The novel yeast assay suggests that BAP export can exceed SRP, particularly when streams are not in equilibrium, such as the rising limb of storms or during active dredging.

Using the 40‐year hourly gridded ERA5 reanalysis, we study the offshore patterns of wind variability using the probability density function (PDF) and the power spectral density (PSD). To summarize wind variability, we compute the Weibull parameters from the PDF and the PSD for six spectral bands: interannual, annual, multimonth, storm, diurnal, and semidiurnal. We characterize the storm spectral peak using a Gaussian function in log10 frequency space. These parameters are plotted along two pole‐to‐pole transects through the Atlantic Ocean at 25°W and the Pacific Ocean at 170°W longitude and at 16 current and proposed offshore wind sites. We test the idea that coastal and open‐ocean wind statistics may be described by a single set of meridional profiles. In mid‐latitudes, the storm band variance exceeding 20 m2 s−2 dominates. The Weibull shape parameter is close to k=2. The storm interval varies from 4 to 7 days depending on location. In the Northern Hemisphere only, the annual variance is significant, exceeding 3 m2 s−2. In the equatorial region, we find steadier winds with small storm variance less than 3 m2 s−2. The Weibull shape parameter is k=4 or greater, suggesting the possibility of a high capacity factor there. The storm interval can exceed 15 days. The equatorial zone has an annual wind variance reaching 2 m2 s−2, comparable to the storm variance. In the tropical Pacific, we find interannual variance associated with El Niño‐Southern Oscillation (ENSO). Semidiurnal variance is detected in the tropics from the atmospheric tide.

Tidal-inlet systems are dynamic features that respond to short-term (e.g., storms) and longer-term processes (e.g., sea-level rise, changes in tidal prism). The Chincoteague Inlet system, located along the northern Eastern Shore of Virginia (USA), is a dynamic coastal complex that experiences rapid change associated with sediment redistribution and a shifting inlet throat due to the southern elongation of adjacent Assateague Island. In this study, a numerical model based on Delft3D with coupled flow–waves, multiclass sediment transport, and morphologic feedback was developed to quantify the hydrodynamic and geomorphic controls within this rapidly evolving inlet–spit system and to develop a more comprehensive understanding of regional to local controls on sediment-transport pathways. Model results show that most of the sand transport along southern Assateague Island is sequestered nearshore and proximally in deeper sinks within Fishing Point, and, of that, only finer sand sizes are transported around the spit, confirming previous analysis and hypothesis. The model also showed that sand transport toward the south increases along Wallops Island and quantified spatially explicit transport trends for selected sediment classes, revealing that coarser sediment bypassing is a punctuated process that is proportional to storms.

As sea-level rise (SLR) and human-made interventions affect coastal currents and sediment transport, coastal barriers have become more vulnerable to the effect of storms, hurricanes, and climate variability. The response of each barrier is unique and depends on wave regime, coastline orientation, weather conditions, bathymetry, and type of human-made interventions, among other factors. In the Magdalena River deltaic barrier, located on the Colombian Caribbean coast, coastal erosion has caused the loss of hundreds of square kilometers of critical ecosystems, such as wetlands and lagoons, since the 1960s. This work aims to analyze the short-term drivers behind the observed loss of lagoons, particularly the drivers of lagoon breaching events and subsequent healing along the deltaic barrier. Lagoon breaching events and healings were detected using satellite imagery, and the timing of these events was related to prior local atmospheric, oceanographic, and fluvial conditions. The findings reveal that the dynamics of the lagoons are driven by extreme river discharges and energetic wave conditions associated with storms or hurricanes. Healing is driven by the sediment supplied by littoral currents and average waves punctuated by energetic events. The cumulative effect of breaching and healing has resulted in a deltaic barrier that has rolled over the lagoons, reducing their size over time. These findings provide a better understanding of the forces of coastal retreat and will help inform future management decisions of the coastal zone.

This datasetcontains the results discussed in the journal article titled 'Novel luminescence diagnosis of storm deposition across intertidal environments'.

More and more use cases require fast, accurate, and reliable processing of large volumes of data. To do this, a distributed stream processing framework is needed which can distribute the load over several machines. In this work, we study and benchmark the scalability of stream processing jobs in four popular frameworks: Flink, Kafka Streams, Spark Streaming, and Structured Streaming. Besides that, we determine the factors that influence the performance and efficiency of scaling processing jobs with distinct characteristics. We evaluate horizontal, as well as vertical scalability. Our results show how the scaling efficiency is impacted by many factors including the initial cluster layout and direction of scaling, the pipeline design, the framework design, resource allocation, and data characteristics. Finally, we give some recommendations on how practitioners should undertake to scale their clusters.

Boulders are excellent candidate deposits to study coastal inundation events by storms and tsunamis due to their significant preservation potential. However, it is difficult to infer how and what forcing dislodged the boulder. We present a new model that enables ensemble and Monte-Carlo-type simulations to study the sensitivity of boulder, the fluid flow, and environmental parameters. Our examples show that boulder transport is complex and nonlinear, and to acknowledge the uncertainties of the boulder's preexisting transport conditions, a range of velocities and environmental parameters should be used to quantify the flow that caused boulder dislodgement. Submitted version

In many regions across the globe, extreme weather events such as storms have increased in frequency, intensity, and duration due to climate change. Ecological theory predicts that such extreme events should have large impacts on ecosystem structure and function. High winds and precipitation associated with storms can affect lakes via short‐term runoff events from watersheds and physical mixing of the water column. In addition, lakes connected to rivers and streams will also experience flushing due to high flow rates. Although we have a well‐developed understanding of how wind and precipitation events can alter lake physical processes and some aspects of biogeochemical cycling, our mechanistic understanding of the emergent responses of phytoplankton communities is poor. Here we provide a comprehensive synthesis that identifies how storms interact with lake and watershed attributes and their antecedent conditions to generate changes in lake physical and chemical environments. Such changes can restructure phytoplankton communities and their dynamics, as well as result in altered ecological function (e.g., carbon, nutrient and energy cycling) in the short‐ and long‐term. We summarize the current understanding of storm‐induced phytoplankton dynamics, identify knowledge gaps with a systematic review of the literature, and suggest future research directions across a gradient of lake types and environmental conditions., Our understanding of ecosystem‐scale responses to storm events is fragmented, and terminological variability in defining a “storm” hinders resolution of generalizable impacts. We provide a comprehensive synthesis of the interactions between physical properties and biological responses in lakes that demonstrates the context‐dependency of storm impacts; lake/watershed attributes and their antecedent conditions mediate the extent to which storms impact lake ecosystems. We develop a framework which conceptualizes how abrupt, storm‐induced changes in the lake environment influence phytoplankton community dynamics through functional traits, identifies current limitations, and highlights several avenues of research to narrow knowledge gaps in synthetic and interdisciplinary ways.

Glider observations show a subsurface chlorophyll maximum (SCM) at the base of the seasonal pycnocline in the North Sea during stable summer conditions. A colocated peak in the dissipation rate of turbulent kinetic energy suggests the presence of active turbulence that potentially generates a nutrient flux to fuel the SCM. A one‐dimensional turbulence closure model is used to investigate the dynamics behind this local maximum in turbulent dissipation at the base of the pycnocline (PCB) as well as its associated nutrient fluxes. Based on a number of increasingly idealized forcing setups of the model, we are able to draw the following conclusions: (a) only turbulence generated inside the stratified PCB is able to entrain a tracer (e.g., nutrients) from the bottom mixed layer into the SCM region; (b) surface wind forcing only plays a secondary role during stable summer conditions; (c) interfacial shear from the tide accounts for the majority of turbulence production at the PCB; (d) in stable summer conditions, the strength of the turbulent diapycnal fluxes at the PCB is set by the strength of the anticyclonic component of the tidal currents., Plain Language Summary: Many midlatitude shelf seas are vertically stratified in summer, where a warm surface layer sits on top of a cold, dense bottom layer. Both of these layers are unproductive environments for phytoplankton—the bottom layer is light limited, and the surface layer is nutrient‐limited. However, abundant phytoplankton is observed directly at the interface between surface and bottom layers. In order to sustain this phytoplankton, nutrient‐rich bottom water needs to be mixed with interface water. While both wind and tides are major causes for mixing in the coastal ocean, we find that the tides alone provide sufficient stirring at the right place to potentially act as an effective fuel pump for the phytoplankton. Interestingly, it is not the strength of the tides alone that counts, rather the sense of rotation of the tidal currents; rotation opposite to the Earth's spin causes more stirring than rotation along with it., Key Points: Turbulence and chlorophyll both peak at the base of the pycnocline on a mid‐latitude shelf. Locally generated turbulence at the pycnocline base is a fuel pump for the subsurface chlorophyll maximum. Amplitude and polarity of the M2 tide govern the local generation of turbulence at the pycnocline base., Helmholtz Association, https://doi.org/10.5281/zenodo.3525787, https://oceancolor.gsfc.nasa.gov/l3/, https://www.cen.uni-hamburg.de/icdc/data/ocean/nsbc.html

The Delft3D hydrodynamic and wave model is used to hindcast the storm surge and waves that impacted La Rochelle, France, and the surrounding area (Aytré, Châtelaillon-Plage, Yves, Fouras, and Île de Ré) during storm Xynthia. These models are validated against tide and wave measurements. The models then estimate the footprint of flow depth, speed, unit discharge, flow momentum flux, significant wave height, wave energy flux, total water depth (flow depth plus wave height), and total (flow plus wave) force at the locations of damaged buildings for which insurance claims data are available. Correlation of the hydrodynamic and wave results with the claims data generates building damage functions. These damage functions are shown to be sensitive to the topography data used in the simulation, as well as the hydrodynamic or wave forcing parameter chosen for the correlation. The most robust damage functions result from highly accurate topographic data and are correlated with water depth or total (flow plus wave) force.

Lake ecosystems are sensitive to local weather conditions, and especially to extremes such as storms and heatwaves. Here we provide an overview of the shorter and longer term effects on lake physics, chemistry and biology. Use of high frequency data from in situ sensors to monitor lakes has provided new insights into these impacts. Many knowledge gaps still exist, however, particularly in relation to the effects on emissions of greenhouse gases from lakes, short-term changes in lake nutrient dynamics, and effects on lake biological communities, parameters for which high frequency data are still scarce.

We acknowledge the World Climate Research Programme's CORDEX project for its role in making available the WCRP CORDEX multi-model data set, and we thank the climate modeling groups for producing and making available their model outputs. D.M. and J.H.C acknowledge funding by the European Union under the Horizon 2020 project EUCP (grant agreement 776613). T. O. was supported by the Scientific and Technological Research Council of Turkey (TUBITAK) under the programme TUBITAK 2219 - International Postdoctoral Research Fellowship. Using a sub-selection of regional climate models at 0.11 degrees (approximate to 12 km) grid resolution from the EURO-CORDEX ensemble, we investigate how the spatial extent of areas associated with the most intensive daily precipitation events changes as a consequence of global warming. We address this by analysing three different warming levels: 1 degrees C, 2 degrees C and 3 degrees C. We find that not only does the intensity of such events increase, but their size will also change as a function of the warming: larger systems becomes more frequent and larger, while systems of lesser extent are reduced in numbers. Publisher's Version Q2 WOS:000709686800002

The Delft3D hydrodynamic and wave model is used to hindcast the storm surge and waves that impacted La Rochelle, France, and the surrounding area (Aytré, Châtelaillon-Plage, Yves, Fouras, and Île de Ré) during storm Xynthia. These models are validated against tide and wave measurements. The models then estimate the footprint of flow depth, speed, unit discharge, flow momentum flux, significant wave height, wave energy flux, total water depth (flow depth plus wave height), and total (flow plus wave) force at the locations of damaged buildings for which insurance claims data are available. Correlation of the hydrodynamic and wave results with the claims data generates building damage functions. These damage functions are shown to be sensitive to the topography data used in the simulation, as well as the hydrodynamic or wave forcing parameter chosen for the correlation. The most robust damage functions result from highly accurate topographic data and are correlated with water depth or total (flow plus wave) force.

20 pages, 15 figures, 3 tables.-- Data availability: Data will be made available on request, A simulation based on a hydro-sedimentary model was conducted for the period between summer 2010 and spring 2012 in the Gulf of Lion (northwestern Mediterranean Sea) to understand the spatial and temporal variability of sediment transport, erosion and deposition on the continental shelf and slope. Datasets of both simulated and observed current, temperature and suspended matter from the shelf and the Cap de Creus Canyon which is the main export route towards the continental slope, were first compared to assess the reliability of the simulation. The simulation shows the massive sediment accumulation near the Rhone River mouth (∼56 % of the inputs), the accretion along the mid-shelf mud belt, and the impact of dense shelf water cascading on sediment resuspension and erosion inside the Cap de Creus Canyon. The two studied autumn–winter periods were strongly contrasted in terms of meteorological conditions and subsequent impacts on the sediment dynamics. During the first period (2010–2011) dominated by marine storms, the shelf sediment underwent strong changes, the Rhone River sediment load accumulated in a relatively small area, stock of littoral sands moved to the inner shelf (20–40 m) while inner shelf fine particles fed the mid-shelf mud belt and the upper Cap de Creus Canyon. During the second period (2011–2012) with very little marine wind and a particularly cold winter, sediment on the shelf underwent little change except for a southwestward growth of the Rhone River prodeltaic deposit. Sediment from the southwestern end of the shelf as well as from the upper Cap de Creus Canyon was flushed toward deeper reaches by dense shelf water cascading. Cascading also had a more moderate impact in the various canyons incising the continental shelf. Our work supports the view of an unbalanced sedimentary system, with a deficit mainly over the inner shelf, whose main driver is probably the strong and fast reduction of particulate matter inputs from the Rhone River (by a factor of 4 in less than one century), This study (including the PhD and Postdoc of G. Mikolajczak) was mainly funded by the AMORAD-project (grant ANR-11-RSNR-0002 of the French program Investissement d’Avenir run by the Agence Nationale de la Recherche). We also benefited from the support of the CHIFRE and DeltaRhone projects of the national EC2CO program. The simulations were performed using HPC resources from CALMIP (Grant P09115) and CINES OCCIGEN (Grant A0040110088). This research was also supported by grant PID2020-114322RB-I00 (FAR-DWO) funded by MCIN/AEI/ 10.13039/501100011033, With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)

La Charente, cours d'eau à faible énergie et peu mobile, est caractérisée par des crues à cinétique lente à l'origine d'inondations aux conséquences parfois désastreuses. Pour autant, aucun travail de recherche approfondi n'a été entrepris sur les inondations de ce fleuve ou sur leur mode de gestion sur une échelle de temps pluriséculaire. Les dernières grandes crues de décembre 1982 et de janvier 1994 ont pourtant révélé une vulnérabilité des territoires face au risque d'inondation. Il apparaît nécessaire de reterritorialiser et de réinscrire l'inondation dans la géohistoire du territoire par la reconstitution d'une chronologie longue des crues de la Charente de 1700 à nos jours à partir du dépouillement de sources archivistiques et bibliographiques et par l'application d'une classification semi-quantitative selon le niveau de gravité de l'événement qui permet de proposer un premier aperçu de la géohistoire des inondations charentaises à travers l'analyse de l'évolution quantitative et qualitative des phénomènes. Cette chronologie inédite est ensuite comparée avec la chronologie des crues des fleuves de la façade atlantique, afin de faire ressortir une éventuelle spécificité de la Charente. Ce travail de recherche souligne également les difficultés spécifiques à travailler sur la géohistoire des inondations d'un cours d'eau à faible énergie en partie lié à un manque important de sources historiques disponibles sur les inondations du fleuve. The Charente river is a low-energy and little mobile river that is characterized by slow kinetic floods which can sometimes cause floodings with disastrous consequences. Still, no historic study exists about floods of this river and their management on a plurisecular timescale. The last major floods of December 1982 and January 1994 showed territories vulnerability face to flood risk. As a consequence, it seems necessary to redefine the territories and reintegrate the floodings in the geohistory of the surrounding area. This article depicts a reconstitute of a flood chronology from 1700 to 2018 extracted from analysis of archival and literature sources and an application of a semi-quantitative classification according to the level of severity of each event in order to propose an initial overview of the floods geohistory of the Charente river through the analysis quantitative and qualitative evolution of the events. A similar analysis performed on various rivers of the Atlantic coast in order to highlight a possible specificity of the Charente river. This work also shows specific difficulties to work on the flood geohistory of the low-energy river partly linked to scarcity of historical sources on the floods of the river.

Climate change and related sea-level rise pose significant threats to lowland coasts. However, the role of key controlling factors responsible for the frequency and landward extent of extreme storm surges is not yet fully understood. Here, we present a high-resolution sedimentary record of extreme storm surge flooding from the non-tidal southern Baltic Sea, spanning two periods: 3.6–2.9 ka BP and 0.7 ka BP until present. Sediments from coastal wetland, including sandy event layers, were analyzed by sedimentological (grain size, loss-on-ignition, micromorphology), geochronological (14C), geochemical (XRF), mineralogical (heavy minerals) and micropaleontological (diatoms) methods. The results show that both periods were characterized by high-frequency of storm surge flooding, in order of 1.3–4.2 events per century. These periods correlate with phases of enhanced storminess in northwest Europe and took place during both rising and fluctuating sea levels. The study shows that the frequency and landward extent of coastal inundation, largely depended on the development of natural barriers (e.g. beach ridges and aeolian foredunes). Thus, in the context of the future coastal storm-surge hazard, the protection of existing coastal barriers and their morphology is essential.

Gigantic jets are electric discharges that on rare occasions can be seen at night shooting out of the top of tropical thunderclouds, reaching the ionosphere (90 km). Using sensitive camera systems and detection software, we recorded 70 events over northern Colombia and adjacent seas, most of them captured between 2016 and 2022. This is the first study to compare the meteorological background conditions for thunderstorms that produced gigantic jets in 48 nights against 83 reference cases with monitored thunderstorms that did not produce jets, using vertical profiles from ERA5 reanalysis near the event location. From the vertical profiles, various meteorological parameters are calculated, grouped by metrics of the low level convective parcel, instability, humidity, warm cloud and mixed phase parameters, and vertical wind shear, not limited to default levels. We report statistically significant differences and effect sizes (Cohen's d) for gigantic jet producing environments compared to null environments. Gigantic jets are produced in conditions with reduced low level temperatures in combination with warmer mid levels. This causes a lower cloud base and higher -10 °C isotherm altitude, thus a greater warm cloud depth, as well as reduced updraft and downdraft buoyancy. Over northern Colombia the non-GJ producing storms tend to grow in an environment that supports more vigorous, multicellular convection by enhanced low-level storm-relative winds and stronger downdrafts. Over western Colombia, the non-GJ cases tend to have a lower equilibrium level while having favorable warm cloud parameters. No evidence is found for hypotheses that upper level vertical wind shear enables gigantic jet production, nor are overshooting tops larger. The findings can be used for forecasting gigantic jets and their climatologically optimal regions on Earth. We speculate that the environmental conditions shift the droplet size distribution towards larger drops at the cost of cloud droplets, with enhanced droplet shattering ice multiplication processes as they freeze. Depending on convective evolution, low rime accretion rates could briefly expand the negative charge region downward by inverse polarity charging while the upper positive charge concentration may weaken at the same time, which could lead to a temporary negatively imbalanced electric potential distribution in the cloud needed for gigantic jet emission.

Coarse woody debris (CWD) is a significant component of the forest biomass pool; hence a model is warranted to predict CWD decomposition and its role in forest carbon (C) and nutrient cycling under varying management and climatic conditions. A process-based model, CWDDAT (Coarse Woody Debris Decomposition Assessment Tool) was calibrated and validated using data from the FACE (Free Air Carbon Dioxide Enrichment) Wood Decomposition Experiment utilizing pine (Pinus taeda), aspen (Populous tremuloides) and birch (Betula papyrifera) on nine Experimental Forests (EF) covering a range of climate, hydrology, and soil conditions across the continental USA. The model predictions were evaluated against measured FACE log mass loss over 6 years. Four widely applied metrics of model performance demonstrated that the CWDDAT model can accurately predict CWD decomposition. The R2 (squared Pearson’s correlation coefficient) between the simulation and measurement was 0.80 for the model calibration and 0.82 for the model validation (P-2 y-1 over the 30 years. The main agents for CWD mass loss were fungi (72.0%) and termites (24.5%), the remainder was attributed to a mix of other wood decomposers. These findings demonstrate the applicability of CWDDAT for large-scale assessments of CWD dynamics, and fine-scale considerations regarding the fate of CWD carbon.

Passive acoustic data collected from four sites in the Monterey Bay National Marine Sanctuary were analyzed to compare the vocalizations of three baleen whale species to the incidence of four storm events. Periods of rainfall were identified using a combination of radar reflectivity data, utilized by weather services around the world, and analysis of the 16 kHz octave level. By utilizing trained human analysis, changes in vocalization patterns were identified for blue whales and humpback whales. Fin whale calls were calculated by analyzing power differences between 12, 20, and 30 Hz frequency bands. Blue whales had the most marked response to the storm events, with rainfall showing the biggest impact. Fin whales also changed their behavior, but only in response to larger amount of rainfall. Humpback whales only responded to the strongest storm event. Although these findings indicate that whales alter their behavior when confronted by weather events, they do not indicate that whales depart an area. These changes in patterns alter the overall soundscape, and this understanding can increase the ability to manage resources for conservation and naval operations. Lieutenant Commander, United States Navy Approved for public release. Distribution is unlimited.

Few studies identify potential hazards affecting canyoning. This activity has an increasing number of practitioners, and hence, a greater number of people are affected by potential natural hazards. Mountain rivers are located in places subject to several hydrological hazards; the risks are mostly connected with floods produced by intense storms or dam operation, but changes in hydrological factors may alter the usual basin behavior given even moderate or less severe storms. Data about flood events and the peak discharge of the 2017 flood in the two studied canyons were collected by means of a quick field survey of water levels after the flood, hydrological modeling, and soil analysis. The present research shows the dramatic consequences of a two-year return period storm affecting a guided group of canyoneers. A previous wildfire changed the soil, leading to hydrophobic conditions and increasing the flood effects. Peak discharge increased from 2 m3 s−1 in normal conditions to 12 m3 s−1 under a hydrophobic regime related to wildfire occurrence; moreover, a reduction in the time of concentration also occurred, pointing to a more powerful and dangerous flood event. In this paper, some hydrological recommendations are highlighted that will be helpful in recreational canyoning management, leading to safer practice.

Dans cet article, nous étudions l’évolution des cordons dunaires à l’est de Dunkerque, au nord de la France, sur une période s’étalant de novembre 2012 à février 2018. Elle se base sur l’analyse de relevés topographiques à haute fréquence, couplés à des données marégraphiques et de vent à la côte ainsi qu’à des enregistrements de vagues au large. Cette période d’étude a été marquée par plusieurs événements tempétueux dont les plus remarquables se sont produits au cours de l’hiver 2013/2014 ainsi qu’en janvier 2017 et en janvier 2018. Bien que l’énergie des vagues enregistrées lors de ces tempêtes ait été modérée, leurs impacts furent assez remarquables et leur effet cumulatif a engendré une érosion importante du cordon dunaire et un recul du trait de côte de près de 10 m. L’analyse de profils topographiques au niveau de deux secteurs dunaires adjacents a révélé une réponse morphologique différente aux tempêtes. Celle-ci serait liée à la variation de paramètres morphologiques, notamment l’altitude du pied de dune et la largeur du haut de plage. Nos résultats montrent également que les processus de régénération des dunes littorales peuvent être très longs sur ce site d’étude. En effet, nous n’avons constaté aucune régénération durant les périodes séparant deux tempêtes, ce qui suggère que ces dunes risquent de connaître des épisodes d’érosion plus fréquentes avec l’élévation contemporaine du niveau de la mer. In this paper, we study coastal dunes evolution east of Dunkirk, northern France, within a mid-term period from November 2012 to February 2018. It is based on high frequency topographic profile measurements coupled with water levels, winds and offshore wave data analysis. This period was characterized by the occurrence of many storms which the most remarkable occurred during the 2013/2014 winter and in January 2017 and January 2018. Despite low wave energy during these storms, their impacts have generated important losses of dune volumes and a shoreline retreat about 10 m. Topographic profiles analysis showed a different morphological response to storms between two adjacent coastal dune areas. This would be related to variations in morphological parameters such as dune foot elevation and upper-beach width. Results showed also that coastal dunes recovery may be very long along this study area. Indeed, no recovery was observed during the period between two storms, suggesting that in the next future, foredunes may experience more frequent erosion with current sea level rise.

The northern Yucatan peninsula is prone to coastal flooding and erosion owing to its low-land elevation and high exposure to storms. Therefore, it is important to assess the capability of the beach-dune system to resist, recover, and adapt from storms in the context of coastal development and climate change. This work aims to investigate the role of human impacts on the spatiotemporal evolution of the Coastal Resilience Index (CRI) in the area. The study is conducted on a prograding micro-tidal beach located on the vicinity of coastal structures. Beach and dune morphometrics, characteristic beach parameters, and maximum shoreline recession were determined from the analysis of beach profiles undertaken along a 2-km straight of coastline during the 2015–2020 period. Moreover, the maximum extreme water levels were estimated using in situ data and numerical models. This information is employed to assess the alongshore and temporal variability of the beach resilience. The results suggest that the beach and dune morphology present alongshore and temporal variability due to the human impacts associated to the dune degradation and the presence of coastal structures. The analysis shows that coastal resilience has been increasing over the past years but presents significant alongshore variations. High CRI values were found at beach transects presenting low anthropogenic impact, whereas low resilience was observed at transects with a degraded dune or located in the vicinity of coastal structures regardless of presenting high progradation rates. The observed beach response during the passage of recent tropical storms is consistent with the CRI values.

Urban floods repeatedly threaten Barcelona, damaging the city infrastructure and endangering the safety of the population. The urban planning of the city, the socioeconomic distribution, its topography, and the characteristics of precipitation systems translate into these flood events having a heterogeneous effect across the city. It means that the coping capacity has a strong dependence on local factors that must be considered when management plans are developed by the municipality. This work aims to contribute to the better knowledge of precipitation structures associated with heavy rainfall events and floods in Barcelona based on radar data and an urban rain gauge network. Radar data have been provided by the Meteorological Service of Catalonia (SMC), while precipitation data, impact data, and early warnings, have been provided by Barcelona Cicle de l’Aigua S.A. (BCASA), for the period 2013–2018. A new radar-based methodology has been developed to identify convective rainfall structures from radar reflectivity volumes (CAPPI and TOP products) to make the analysis easier. The high computing speed of the procedure allows efficient analysis of a large set of convective cells without scarifying temporal resolution of radar data. Both rainfall fields (radar and rain gauge, respectively) have been compared. Then through the identified rainfall convective structures, thunderstorm hotspots have been identified. Considering an alert indicator from BCASA and the reported incidents, episodes with the highest impact have been analysed in depth. Results show 207 significant rainfall episodes in the ROI for the six years, which are mainly concentrated between September and November. The fact that significant episodes are usually produced by highly convective rain corroborates the advantage of using radar images as a tool to detect any maxima even when no rain gauge is there. In 64 of the episodes, the level of pre-alert was achieved with a maximum frequency between August and September. The proposed algorithm shows more than 8000 centroids of convective cells from 189 cases. Whilst maximum surface reflectivity over 45 dBZ is more prone to occur near the coastline, the centroids of storm cells tend to concentrate more inland. The final objective is to improve the actions taken by the organisation responsible for managing urban floods, which have seen Barcelona recognised as a model city for flood resilience by the United Nations.

Treballs Finals de Grau de Física, Facultat de Física, Universitat de Barcelona, Curs: 2021, Tutora: Maria del Carmen Llasat, The aim of this article is to study the phenomena associated with strong wind and compound events where this hazard intervenes in the region of North Girona. Of the two blocks in which this work is divided, the first one focuses on the synthesis of the literature about the most common winds in L'Empordà, floods and compound events. The second one focuses on the analysis of the situations that have affected the area based on rainfall (1950-2015), wind (1997-2018) and coastal storm (1973-2013) data provided by the M-CostAdapt project. The compound events that have been taken into account are the combination of two or three of these hazards. In total, 116 compound events took place between 1997 and 2013, mainly in September and October. The most common type was composed by heavy rain and Tramuntana wind, with a maximum wind gust between 45 and 75 Km/h. One of the strongest storms that affected Catalonia in recent years, storm Gloria, has also been analyzed

Overwash is a natural storm-related process that occurs when wave runup overcomes the dune crest. Because coastlines are globally occupied, overwash is a hazardous process and there is a need to identify vulnerable areas. This study proposes a method to detect overwash-prone areas in the Ancao peninsula, Portugal, and eventually outlines a vulnerability map. Dune base (D-LOW) and crest (D-HIGH) topography were surveyed. Three different storm scenarios (5-, 10- and 25- year return period storms) and associated waves and sea level were determined. According to these data, extreme wave runup (R-HIGH) was calculated by a parameterisation set for intermediate-reflective beaches. The maps for collision and overwash regimes were designed by comparing R-HIGH values with D-LOW and D-HIGH. Almost the entire dune base along the peninsula is vulnerable to collision regime. The overwash process was identified mainly along the tidal inlet hazard area and within the human-occupied portion of the beach, where overwash is expected to occur within 5 years of return period. The developed method considers the main overwash driving forces and proved to identify hazardous areas previously observed in the area. Occasional differences between modelled and observed overwash areas can be attributable to equipment errors, morphology interpretation subjectivity and maladjustments in runup parameterisation. Nevertheless, the method proved to be effective in reproducing the overall Ancao peninsula vulnerability and can be widely applied. Therefore, it is a simple and potentially important tool for coastal management that enables mitigation strategies for occupied coasts and assessment of geological and ecological consequences in natural areas. info:eu-repo/semantics/publishedVersion

Cicadas tend to be affected by vicariance reflecting poor mobility of nymphs underground and weak flying ability of adults. However, modern collection records of invasive cicada, combined with records of typhoon tracks, and newly obtained phylogeographic data suggest long distance, relatively instantaneous, dispersal of some vicariantly speciated cicadas. We address the importance of this typhoon dispersal mechanism applied to representative species of east Asian endemic cicadas ofCryptotympana,Mogannia,EuterpnosiaandMeimuna. We combine BEAST-dated phylogenic and haplotype network analyses, modern collection data of non-native cicadas available in reports of the Japanese insect associations, modern typhoon records by Japan Meteorological Agency, and our own Quaternary geological constriction data. In conclusion, although Ryukyu endemic cicadas were vicariantly speciated, endemic cicadas on some islands were accidentally dispersed long distances to another island by typhoons, particularly those associated with super typhoons generated since 1.55 Ma.

Vascular epiphytes represent almost 10% of all terrestrial plant diversity. Being structurally dependent on trees, epiphytes live at the interface of vegetation and atmosphere, making them susceptible to atmospheric changes. Despite the extensive research on vascular epiphytes, little is known about wind disturbance on these plants. Therefore, this study investigated the wind-epiphyte mechanical interactions by quantifying the drag forces on epiphytic bromeliads when subjected to increasing wind speeds (5–22 m s-1) in a wind tunnel. Drag coefficients (Cd) and Vogel exponents (B) were calculated to quantify the streamlining ability of different bromeliad species. Bromeliads’ reconfiguration occurred first via bending and aligning leaves in the flow direction. Then leaves clustered and reduced the overall plant frontal area. This reconfiguration caused drag forces to increase at a slower rate as wind velocity increased. In the extreme case, drag force was reduced by 50% in a large Guzmania monostachia individual at a wind velocity of 22 m s-1, compared to a stiff model. This species had one of the smallest Cd (0.58) at the highest wind velocity, and the largest negative mean B (-0.98), representing the largest reconfiguration capacity amongst the tested bromeliads. The streamlining ability of bromeliads was mainly restricted by the rigidity of the lower part of the plant where the leaves are already densely clustered. Wind speeds used in this study were generally low as compared to storm force winds. At these low wind speeds, reconfiguration was an effective mechanism for drag reduction in bromeliads. This mechanism is likely to lose its effectiveness at higher wind speeds when continuous vigorous fluttering results in leaf damage and aspects such as root-attachment strength and substrate stability become more relevant. This study is a first step towards an understanding of the mechanical bottleneck in the epiphyte-tree-system under wind stress.

Rivers integrate and transport particulate organic carbon (POC) from multiple sources with varied diagenetic histories. A significant amount of POC is delivered to rivers during storm events, but the sources and fates of the mobilized material are often unclear. To gauge the relative contributions of variability of different input sources, this study uses a biomarker approach that broadly characterizes organic matter on the molecular level. Suspended sediment was collected during a storm in October 2015 at three nested sampling locations along Clear Creek in Iowa, U.S.A. Supplemented with bulk elemental and C-isotopic measurements, biomarker analyses were obtained to identify changes in the sources and the diagenetic state of the POC. Fatty acid-rich organic matter was attributed to the mobilization of algal mats in the stream channel at the early stage of the storm as precipitation initiated and water velocities began to increase. A significant contribution of lignin-rich material occurred at peak precipitation and elevated discharge signifying erosion from row crop field surfaces and bank soil sources. Tracers of oxidized lignin and soil organic matter suggested that this was a partially time-resolved mixture of fresh and degraded material derived. Storm-induced variations of biomarkers were observed at the three sampling stations located throughout the watershed. The mixing patterns became more complex as the storm pulse moved downstream due to the additive contributions of multiple tributaries and the hypothesized increasing relative importance of alluvial bank erosion. The increase is attributed to a systematic transition in basin geomorphology from a V-shape in the upper reach to a wider box-shaped valley in the lower reach. Even though standing crop biomarker concentration measurements revealed a diversity of sources over time, the complex mixture of POC associated with peak discharge dominated the flux of material downstream. This study highlights the complexity of storm-initiated C-transport and the need for high spaciotemporal resolution broad spectrum tracer studies in the future.

Wind-related disasters will bring more devastating consequences to cities in the future with a changing climate, but relevant studies have so far provided insufficient information to guide adaptation actions. This study aims to provide an in-depth elaboration of the contents discussed in open access literature regarding wind disaster adaptation in cities. We used the Latent Dirichlet Allocation (LDA) to refine topics and main contents based on 232 publications (1900 to 2019) extracted from Web of Science and Scopus. We conducted a full-text analysis to filter out focal cities along with their adaptation measures. The results show that wind disaster adaptation research in cities has formed a systematic framework in four aspects: 1) vulnerability and resilience of cities, 2) damage evaluation, 3) response and recovery, and 4) health impacts of wind disaster. Climate change is the background for many articles discussing vulnerability and adaptation in coastal areas. It is also embedded in damage evaluation since it has the potential to exacerbate disaster consequences. The literature is strongly inclined towards more developed cities such as New York City and New Orleans, among which New York City associated with Hurricane Sandy ranks first (38/232). Studies on New York City cover all the aspects, including the health impacts of wind disasters which are significantly less studied now. Distinct differences do exist in the number of measures regarding the adaptation categories and their subcategories. We also find that hard adaptation measures (i.e., structural and physical measures) are far more popular than soft adaptation measures (i.e., social and institutional measures). Our findings suggest that policymakers should pay more attention to cities that have experienced major wind disasters other than New York. They should embrace the up-to-date climate change study to defend short-term disasters and take precautions against long-term changes. They should also develop hard-soft hybrid adaptation measures, with special attention on the soft side, and enhance the health impact study of wind-related disasters., PLoS ONE, 16 (3), ISSN:1932-6203

Storm waves, after breaking or overtopping, generate strong onshore flows that do significant mechanical work, including eroding and transporting large boulders. The waves can be amplified on approach, and the flows themselves may be further intensified by local topographic effects. These processes are currently poorly parameterised, but are of great importance for understanding the interactions between waves and coasts. We present a highly generalised equation for estimating maximal coastal wave heights and consequent onshore flow velocities. Although very approximate, this method contains no embedded assumptions, and thus provides a more realistic first-order check of storm wave capabilities than previous approaches. Initial analysis suggests that exceptional wave impacts may generate onshore flow velocities up to six times greater than expected from previous approaches. Although the probability of occurrence in any given storm is very low, the possibility of such extreme values cannot be ignored, especially when interpreting ancient deposits of large boulders. The equations presented here can be used as a first-order test for coastal boulder deposits currently interpreted as tsunami deposits, to evaluate whether a storm-wave origin should be reconsidered. This approach could also be employed at coasts in general, to evaluate long-term probabilities of damaging flows, as a component of coastal risk analysis.

The role of storm events in controlling chlorophyll distribution along the oligotrophic Rottnest continental shelf is examined data collected by autonomous ocean gliders combined with meteorological data. Spatial and temporal distribution of chlorophyll concentrations were obtained from a repeated transect across the shallow continental shelf that revealed complex relationships among wind events (e.g., differences in wind speed and direction) and chlorophyll concentrations. Data indicated that the water column responded rapidly to changes in wind speeds alternating between stratification, de-stratification and vice-versa over 1–3 days. Under low wind conditions (wind speeds < 7 ms–1), the water column was stratified and dense shelf water cascades (DSWC) was the dominant feature. The majority of DSWC events were associated with synchronous increases in chlorophyll and suspended sediment, often close to the seabed. During storm events (wind speeds > 15 ms–1) higher chlorophyll values were present throughout the vertically mixed water column. Maximum chlorophyll concentrations, more than double that due to climatology, were observed 1–3 days after the passage of storms subsequent to sediment re-suspension. Storm events, with an onshore component, promoted downwelling, the water column retained vertical stratification, and DSWC was present across the shelf. Here, DSWC intensified with higher chlorophyll in the cascaded water extending further offshore. It is concluded that wind speed and direction are the dominant parameters controlling the distribution of chlorophyll particularly during storm events.

Caribbean Acropora spp. corals have undergone a decline in cover since the second half of the twentieth century. Loss of these architecturally complex and fast-growing corals has resulted in significant, cascading changes to the character, diversity, and available eco-spaces of Caribbean reefs. Few thriving Acropora spp. populations exist today in the Caribbean and western North Atlantic seas, and our limited ability to access data from reefs assessed via long-term monitoring efforts means that reef scientists are challenged to determine resilience and longevity of existing Acropora spp. reefs. Here we used multiple dating methods to measure reef longevity and determine whether Coral Gardens Reef, Belize, is a refuge for Acropora cervicornis against the backdrop of wider Caribbean decline. We used a new genetic-aging technique to identify sample sites, and radiocarbon and high-precision uranium-thorium (U-Th) dating techniques to test whether one of the largest populations of extant A. cervicornis in the western Caribbean is newly established after the 1980s, or represents a longer-lived, stable population. We did so with respect for ethical sampling of a threatened species. Our data show corals ranging in age from 1910 (14C) or 1915 (230Th) to at least November 2019. While we cannot exclude the possibility of short gaps in the residence of A. cervicornis earlier in the record, the data show consistent and sustained living coral throughout the 1980s and up to at least 2019. We suggest that Coral Gardens has served as a refuge for A. cervicornis and that identifying other, similar sites may be critical to efforts to grow, preserve, conserve, and seed besieged Caribbean reefs.

Helping the world's coastal communities adapt to climate change impacts requires evaluating the vulnerability of coastal communities and assessing adaptation options. This includes understanding the potential for 'natural' infrastructure (ecosystems and the biodiversity that underpins them) to reduce communities' vulnerability, alongside more traditional 'hard' infrastructure approaches. Here we present a spatially explicit global evaluation of the vulnerability of coastal-dwelling human populations to key climate change exposures and explore the potential for coastal ecosystems to help people adapt to climate change (ecosystem-based adaptation (EbA)). We find that mangroves and coral reefs are particularly well situated to help people cope with current weather extremes, a function that will only increase in importance as people adapt to climate change now and in coming decades. We find that around 30.9 million people living within 2km of the coast are highly vulnerable to tropical storms and sea-level rise (SLR). Mangroves and coral reefs overlap these threats to at least 5.3 and 3.4 million people, respectively, with substantial potential to dissipate storm surges and improve resilience against SLR effects. Significant co-benefits from mangroves also accrue, with 896 million metric tons of carbon stored in their soils and above- and below-ground biomass. Our framework offers a tool for prioritizing 'hotspots' of coastal EbA potential for further, national and local analyses to quantify risk reduction and, thereby, guide investment in coastal ecosystems to help people adapt to climate change. In doing so, it underscores the global role that conserving and restoring ecosystems can play in protecting human lives and livelihoods, as well as biodiversity, in the face of climate change.

Storms can have devastating impacts on barrier coasts causing coastal erosion, partial inundation, and possibly the breaching of barrier islands. The breaching of barrier islands provides a mechanism for the creation of new tidal inlets that connect the backbarrier basin (or lagoon) and the outer sea. As a new tidal inlet affects both the basin and the hydrodynamics of existing inlets, it is important to understand why an initial breach either closes or may evolve into a new tidal inlet. To this end, we performed a Monte Carlo analysis using an idealized model capable of simulating the long-term morphological evolution of multiple tidal inlets connected to a single backbarrier basin. To do so required the creation of a stochastic shell, as a new element around this existing barrier coast model. Our results demonstrate that barrier coast systems tend towards an equilibrium value for the number of inlets per kilometer of barrier coast and total inlet cross section. This even holds with the continuous stochastic forcing of storm-induced breaches. This finding implies that if a new breach opens in a coast that is already in equilibrium, existing inlets will shrink and may close if the new breach remains open. Furthermore, we find that climate-driven changes in storm frequency will modify the timescales in which barrier coasts reach their equilibrium state. Finally, we find that the distance between a new breach and its nearest neighbor is more important for its survival than the size of the breach or the degree of saturation of the barrier coast.

RESUMEN: El presente trabajo se centra en los temporales marítimos acaecidos en el litoral costero de la zona norte de España a partir de datos met-oceánicos históricos recogidos durante 3 décadas (1985 – 2014) en 16 ubicaciones del litoral. Por un lado, se ha recopilado la información procedente de diversas fuentes (medios de comunicación, informes del Consorcio de Seguro, etc), con el fin de datar, localizar y obtener información detallada de aquellos eventos que han tenido mayor impacto en la sociedad. Por otro lado, a partir de las bases de datos históricas proporcionadas (oleaje, marea astronómica y meteorológica y viento) se han caracterizado los eventos extremos, seleccionando estos mediante excedencias sobre un umbral y analizando sus propiedades para diferentes parámetros del estado de mar (altura de ola significante, periodo, duración del evento, etc). Se ha realizado una clasificación de los temporales empleando técnicas de minería de datos, consiguiendo agrupar los mismos en base a 3 parámetros fundamentales. El análisis de los datos de las estaciones ha permitido, de la misma manera, realizar una división de la zona analizada en 3 áreas en función de la tipología de dichas estaciones obteniendo resultados característicos y diferenciadores de las zonas. Esto, a su vez, ha permitido analizar los temporales de una manera diferenciada en función de la zona de afección. También se ha estimado el régimen extremal para las ubicaciones de estudio y se ha evaluado el periodo de retorno asociado a los temporales de mayor intensidad históricos. Por último, se ha evaluado el impacto costero de los temporales marítimos a través de un análisis estadístico de la cota de inundación (añadiendo al nivel del mar la componente asociada al oleaje) y del daño sobre estructuras de defensa costera (diques en talud). Para evaluar el daño, se ha aplicado la formulación de Van de Meer para los peores temporales s, cuantificando el efecto destructivo producido por los eventos en las estructuras. Se han obtenido resultados claros y concluyentes de afección que permiten afirmar la correlación existente entre los datos registrados por las estaciones y la hemeroteca analizada. ABSTRACT: This work is an analysis of the incidence of coastal phenomena on the coast of northern Spain based on historical data off waves and wind collected over 3 decades (1985 - 2014) from 16 coastal stations. Based on the results obtained, a classification of the storms has been made using data analysis techniques and managing to group them based on 3 fundamental parameters. The analysis of the data from the stations has also made it possible to divide the area analysed into 3 areas according to the typology of these stations, obtaining results that are characteristic of and differentiate the areas. This, in turn, has allowed the analysis of the storms in a differentiated way according to the area of affection. In an effort to apply a practical and socially perceptible component to the work carried out, newspaper libraries from various media have been analysed to find similarities with the main coastal phenomena detected through the models used and the perception that society has had of the events that have occurred. Finally, and by applying Van de Meer's formulation, the damage caused by the worst storms recorded by both the stations analysed and the data collected by the media analysed, which in most cases coincide, has been analysed in order to quantify the destructive effect produced by the events on the structures. Clear and conclusive results have been obtained which allow us to affirm the correlation between the data recorded by the stations and the newspaper library analysed. Máster en Ingeniería costera y portuaria

Identifying patterns in data relating to extreme rainfall is important for classifying and estimating rainfall and flood frequency distributions routinely used in civil engineering design and flood management. This study demonstrates the novel use of several self-organising map (SOM) models to extract the key moisture pathways for extreme rainfall events applied to example data in northern Spain. These models are trained using various subsets of a backwards trajectory data set generated for extreme rainfall events between 1967 and 2016. The results of our analysis show 69.2% of summer rainfall extremes rely on recirculatory moisture pathways concentrated on the Iberian Peninsula, whereas 57% of winter extremes rely on deep-Atlantic pathways to bring moisture from the ocean. These moisture pathways have also shown differences in rainfall magnitude, such as in the summer where peninsular pathways are 8% more likely to deliver the higher magnitude extremes than their Atlantic counterparts.

Advances in near real-time rainstorm prediction using remote sensing have offered important opportunities for effective disaster management. However, this information is subject to several sources of systematic errors that need to be corrected. Temporal and spatial characteristics of both satellite and in-situ data can be combined to enhance the quality of storm estimates. In this study, we present a spatiotemporal object-based method to bias correct two sources of systematic error in satellites: displacement and volume. The method, Spatiotemporal Contiguous Object-based Rainfall Analysis for Bias Correction (ST-CORAbico), uses the spatiotemporal rainfall analysis ST-CORA incorporated with a multivariate kernel density storm segmentation for describing the main storm event characteristics (duration, spatial extension, volume, maximum intensity, centroid). Displacement and volume are corrected by adjusting the spatiotemporal structure and the intensity distribution, respectively. ST-CORAbico was applied to correct the early version of the Integrated Multi-satellite Retrievals for the Global Precipitation Mission (GPM-IMERG) over the Lower Mekong basin in Thailand during the monsoon season from 2014 to 2017. The performance of ST-CORABico is compared against the Distribution Transformation (DT) and Gamma Quantile Mapping (GQM) probabilistic methods. A total of 120 storm events identified over the study area were classified into short and long-lived storms by using a k-means cluster analysis method. Examples for both storm event types describe the error reduction due to location and magnitude by ST-CORAbico. The results showed that the displacement and magnitude correction made by ST-CORAbico considerably reduced RMSE and bias of GPM-IMERG. In both storm event types, this method showed a lower impact on the spatial correlation of the storm event. In comparison with DT and GQM, ST-CORAbico showed a superior performance, outperforming both approaches. This spatiotemporal bias correction method offers a new approach to enhance the accuracy of satellite-derived information for near real-time estimation of storm events.

An assessment of the National Aeronautics and Space Administration NASA's Cyclone Global Navigation Satellite System (CyGNSS) mission for biomass studies is presented in this work on rain, coniferous, dry, and moist tropical forests. The main objective is to investigate the capability of Global Navigation Satellite Systems Reflectometry (GNSS-R) for biomass retrieval over dense forest canopies from a space-borne platform. The potential advantage of CyGNSS, as compared to monostatic Synthetic Aperture Radar (SAR) missions, relies on the increasing signal attenuation by the vegetation cover, which gradually reduces the coherent scattering component scoh,0. This term can only be collected in a bistatic radar geometry. This point motivates the study of the relationship between several observables derived from Delay Doppler Maps (DDMs) with Above-Ground Biomass (AGB). This assessment is performed at different elevation angles ?e as a function of Canopy Height (CH). The selected biomass products are obtained from data collected by the Geoscience Laser Altimeter System (GLAS) instrument on-board the Ice, Cloud, and land Elevation Satellite (ICESat-1). An analysis based on the first derivative of the experimentally derived polynomial fitting functions shows that the sensitivity requirements of the Trailing Edge TE and the reflectivity G reduce with increasing biomass up to ~ 350 and ~ 250 ton/ha over the Congo and Amazon rainforests, respectively. The empirical relationship between TE and G with AGB is further evaluated at optimum angular ranges using Soil Moisture Active Passive (SMAP)-derived Vegetation Optical Depth (VOD), and the Polarization Index (PI). Additionally, the potential influence of Soil Moisture Content (SMC) is investigated over forests with low AGB. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.

Resumen: La reconstrucción del clima en el pasado se ha realizado recurriendo a gran cantidad de técnicas tales como el carbono 14, el análisis de sedimentos, la paleobotánica, la paleozoología... Frente a todo esto, el patrimonio documental español es extremadamente rico en datos sobre sequías, riadas, inundaciones, tormentas, terremotos... no sólo de España, sino de prácticamente todo el planeta. No siempre lo suficientemente explotado, este artículo pretende mostrar las enormes posibilidades que dicho patrimonio ofrece para conocer el clima del pasado y su incidencia en la sociedad desde la Edad Media hasta la actualidad. Abstract: The reconstruction of the climate in the past has been made using a lot of techniques such as carbon 14, sediment analysis, paleobotany, paleozoology ... In contrast to all this, the Spanish documentary heritage is extremely rich in data on droughts, floods, storms, earthquakes... not only concerning to Spain, but also almost the entire planet. Not always sufficiently explored, this article intends to show the enormous possibilities that this heritage offers to know the climate of the past and its impact on society from the Middle Ages to the present.

Este artículo contiene 25 páginas, 9 figuras., In the Anthropocene, watershed chemical transport is increasingly dominated by novel combinations of elements, which are hydrologically linked together as ‘chemical cocktails.’ Chemical cocktails are novel because human activities greatly enhance elemental concentrations and their probability for biogeochemical interactions and shared transport along hydrologic flowpaths. A new chemical cocktail approach advances our ability to: trace contaminant mixtures in watersheds, develop chemical proxies with high-resolution sensor data, and manage multiple water quality problems. We explore the following questions: (1) Can we classify elemental transport in watersheds as chemical cocktails using a new approach? (2) What is the role of climate and land use in enhancing the formation and transport of chemical cocktails in watersheds? To address these questions, we first analyze trends in concentrations of carbon, nutrients, metals, and salts in fresh waters over 100 years. Next, we explore how climate and land use enhance the probability of formation of chemical cocktails of carbon, nutrients, metals, and salts. Ultimately, we classify transport of chemical cocktails based on solubility, mobility, reactivity, and dominant phases: (1) sieved chemical cocktails (e.g., particulate forms of nutrients, metals and organic matter); (2) filtered chemical cocktails (e.g., dissolved organic matter and associated metal complexes); (3) chromatographic chemical cocktails (e.g., ions eluted from soil exchange sites); and (4) reactive chemical cocktails (e.g., limiting nutrients and redox sensitive elements). Typically, contaminants are regulated and managed one element at a time, even though combinations of elements interact to influence many water quality problems such as toxicity to life, eutrophication, infrastructure corrosion, and water treatment. A chemical cocktail approach significantly expands evaluations of water quality signatures and impacts beyond single elements to mixtures. High-frequency sensor data (pH, specific conductance, turbidity, etc.) can serve as proxies for chemical cocktails and improve real-time analyses of water quality violations, identify regulatory needs, and track water quality recovery following storms and extreme climate events. Ultimately, a watershed chemical cocktail approach is necessary for effectively co-managing groups of contaminants and provides a more holistic approach for studying, monitoring, and managing water quality in the Anthropocene., This work was funded by USDA (award # 2016-67019-25280) and NSF-EPSCoR (#1641157) for supporting collaborations at the AGU Chapman Conference on Extreme Climate Events. Significant funding for data collection/analyses in this paper was provided by NSF EAR1521224, NSF CBET1058502, NSF Coastal SEES1426844, NSF DEB-0423476 and DEB-1027188, NSF RI EPSCoR NEWRnet Grant No. IIA-1330406, EPA ORD, Chesapeake Bay Trust, and Multi-state Regional Hatch Project S-1063.

This study analyzes the effects of climate-related disasters on international trade in Southeast Asia. We use monthly trade data to examine the relationship between disaster shocks and bilateral export flows. The empirical analysis shows that natural disasters have a significant negative effect on exports. The estimation results suggest that floods cause an immediate decrease in exports by 3–5% of monthly mean export values. In addition, the effect persists in the post-disaster period, with floods causing annual export losses of 2% of average export values. We further investigate the impact of disasters by product group, and show that disasters are negatively associated with the exports of agricultural and manufacturing products. The findings suggest that extreme weather events have severe repercussions on Southeast Asia, where exports play an important role in economic development.

Coastal systems are the result of a natural equilibrium between hydrodynamic, atmospheric, and terrestrial parameters and sediment dynamics. In the Anthropocene, this equilibrium in many coastal regions can be altered by human activities. These activities may globally magnify the effects of extreme meteorological events and sea level rise and directly influence coastal processes down to a local scale within and between river catchments, the sea, and the coast. While most interventions, such as urban development, seawalls, and jetties are placed for specific human benefits, their indirect effects on coastal economies, societies and ecosystems can be significant. [...]