Coastal storm waves detection system design using Beaufort scale standardization and Sugianto wave forecasting method in Timbulsloko, Demak, Central Java, Indonesia

Storm is defined as a disturbance of the atmosphere marked by winds and usually by rain. Coastal storms must comprise a maritime component, such as waves, currents and/or water levels. Coastal storm detection is necessary so the number of casualties and losses caused by these events can be reduced. The method used in this system is the Sugianto wave forecasting method with standardization of coastal storms using the Beaufort scale. The purpose of this study is to built up an internet of things based system to observe coastal storm information and wave forecasting data from wind speed data that obtained in Timbulsloko, Demak, Central Java, Indonesia. The tidal data is processed using the Admiralty method. This system was built using Arduino Uno equipped with anemometer JL-FS2 to measure wind and waves parameters. The power source from 100 wp solar panels stored in a 40 Ah accumulator. Data from field instrument is stored to the IoT MAPID database using NodeMCU ESP8266. This system is placed in Timbulsloko, Demak. The results of field observation then validated using BMKG. This method could be applied in other location along the north coast of Java. The results of field observation showed an average wind speed 3.9848 m/s; significant wave height 0.4632 m; significant wave period 3.8641 s; wave energy 493.90 J/m2; wind energy 116.74 W/m2.

Skew Surge and Storm Tides of Tropical Cyclones in the Delaware and Chesapeake Bays for 1980–2019

Coastal flooding poses the greatest threat to human life and is often the most common source of damage from coastal storms. From 1980 to 2020, the top 6, and 17 of the top 25, costliest natural disasters in the U.S. were caused by coastal storms, most of these tropical systems. The Delaware and Chesapeake Bays, two of the largest and most densely populated estuaries in the U.S. located in the Mid-Atlantic coastal region, have been significantly impacted by strong tropical cyclones in recent decades, notably Hurricanes Isabel (2003), Irene (2011), and Sandy (2012). Current scenarios of future climate project an increase in major hurricanes and the continued rise of sea levels, amplifying coastal flooding threat. We look at all North Atlantic tropical cyclones (TC) in the International Best Track Archive for Climate Stewardship (IBTrACS) database that came within 750 km of the Delmarva Peninsula from 1980 to 2019. For each TC, skew surge and storm tide are computed at 12 NOAA tide gauges throughout the two bays. Spatial variability of the detrended and normalized skew surge is investigated through cross-correlations, regional storm rankings, and comparison to storm tracks. We find Hurricanes Sandy (2012) and Isabel (2003) had the largest surge impact on the Delaware and Chesapeake Bay, respectively. Surge response to TCs in upper and lower bay regions are more similar across bays than to the opposing region in their own bay. TCs that impacted lower bay more than upper bay regions tended to stay offshore east of Delmarva, whereas TCs that impacted upper bay regions tended to stay to the west of Delmarva. Although tropical cyclones are multi-hazard weather events, there continues to be a need to improve storm surge forecasting and implement strategies to minimize the damage of coastal flooding. Results from this analysis can provide insight on the potential regional impacts of coastal flooding from tropical cyclones in the Mid-Atlantic.

Classifying compound coastal storm and heavy rainfall events in the north-western Spanish Mediterranean

The north-west (NW) Mediterranean coastal zone is a populous and well-developed area in which the impact of natural hazards like flash floods and coastal storms can result in frequent and significant damages. Although the occurrence and impacts of such hazards have been widely covered, few studies have considered their combined impact on the region, which would result in more damage. Within this context, this study analyses the occurrence and characteristics of compound extreme events of heavy rainfall episodes (as a proxy for flash floods) and coastal storms (using the maximum significant wave height) along the Catalan coast as a paradigm of the NW Mediterranean. Two different types of events are considered: multivariate, in which the two hazards occur at the same location, and spatially compounding, in which they occur within the same limited time window, and their impacts accumulate at distinct and separate locations. The analysis is regionally performed along a coastline extension of about 600 km by considering seven coastal sectors and their corresponding river catchment basins. Once the compound events are analysed, the synoptic atmospheric pressure fields are analysed to determine the prevailing weather conditions that generated them. Finally, a Bayesian network is used to fully characterize these events over the territory. The obtained results show that the NW Mediterranean, represented by the Catalan coast, has a high probability of experiencing compound extreme events. Despite the relatively small size of the study area, there are significant variations in the event characteristics along the territory, with the most frequent type being spatially compound, except in the northernmost sectors where multivariate events dominate. These northern sectors also present the highest correlation in the intensity of both hazards. Three representative synoptic situations have been identified as dominant for the occurrence of these events, with different relative importance levels of the compounding drivers (rainfall and waves) and different distributions of impacts across coastal basins. Overall, results obtained from specific events indicated that heavy rainfall is related to the most significant impacts despite having a larger spatial reach.

Analysis of coastal storms for their application in harbours and coastal structures design

Οι καταιγίδες και οι φυσικές καταστροφές που συχνά προκαλούν, απασχολούν τον άνθρωπο από την αρχαιότητα. Στις μέρες μας, η σφοδρότητα των καταιγίδων είναι εντονότερη από αυτή του παρελθόντος. Πιο συγκεκριμένα, οι επιπτώσεις των καταιγίδων στις ακτές και τις παράκτιες περιοχές θεωρείται ότι θα είναι ακόμη πιο καταστροφικές στο άμεσο μέλλον λόγω της κλιματικής κρίσης, καθιστώντας πλέον επιτακτική τη συστηματική έρευνα και την ανάλυση των καταιγίδων.Οι καταιγίδες συχνά ταυτίζονται με τους κυκλώνες και τους τυφώνες, ενώ ουσιαστικά ως μια ευρύτερη έννοια περιγράφουν τα ακραία υδρομετεωρολογικά γεγονότα. Ωστόσο, ο όρος των «παράκτιων καταιγίδων» χρησιμοποιείται ειδικότερα για να περιγράψει τις καταιγίδες που πλήττουν τις ακτές και προκαλούν επιπτώσεις στη μορφολογία των ακτών, στη λειτουργικότητα και στην ευστάθεια των λιμενικών και παράκτιων έργων. Η επίδραση των παράκτιων καταιγίδων στη ζωή των ανθρώπων και η φύση τους ως ακραία φαινόμενα ήταν τα αρχικά κίνητρα για την εκπόνηση της παρούσας διατριβής.Για τον ορισμό και τον εντοπισμό των παράκτιων καταιγίδων χρησιμοποιούνται συνήθως οι ατμοσφαιρικές και οι κυματικές παράμετροι, όπως το ύψος κύματος (Η) και η περίοδος του κύματος (Τ). Ακολουθώντας τη θεωρία των ακραίων τιμών, o εντοπισμός των παράκτιων καταιγίδων πραγματοποιείται μέσω της εφαρμογής των κατωφλιών των σημαντικών αυτών παραμέτρων και στη συνέχεια γίνεται η ανάλυσή τους. Για την καλύτερη κατανόηση των παράκτιων καταιγίδων, ιδιαίτερη προσοχή δίνεται στην περιγραφή της σχέσης των μεταβλητών που τις ορίζουν και κατά συνέπεια στη μοντελοποίηση τους. Στη βιβλιογραφία η ανάλυση των παράκτιων καταιγίδων περιορίζεται συνήθως σε συγκεκριμένες περιοχές, ενώ για τη μοντελοποίηση τους χρησιμοποιείται η θεωρία των συζεύξεων, λαμβάνοντας υπόψη δυο ή τρείς μεταβλητές. Η θεωρία των συζεύξεων αναπτύχθηκε κυρίως στον τομέα της Στατιστικής και χρησιμοποιείται ευρέως στα Οικονομικά και στην Υδρολογία. Η εφαρμογή των συζεύξεων απαιτεί αρκετούς μαθηματικούς υπολογισμούς και χρειάζεται ιδιαίτερη προσοχή, ωστόσο ενδείκνυται για τη μελέτη πολυμεταβλητών φαινομένων, όπως είναι οι παράκτιες καταιγίδες. Λόγω των παραπάνω, στόχοι της παρούσας διατριβής αποτελούν 1) η ανάλυση των παράκτιων καταιγίδων και 2) η μοντελοποίηση τους μέσω των συζεύξεων. Παράλληλα, επιδιώκεται η περιγραφή μιας ολοκληρωμένης μεθοδολογίας για τον εντοπισμό των παράκτιων καταιγίδων και η εφαρμογή των συζεύξεων για α) τη μελέτη της εξάρτησης δυο μεταβλητών κατά τη διάρκεια μιας παράκτιας καταιγίδας, β) την προσομοίωση των παράκτιων καταιγίδων μιας περιοχής και γ) τον υπολογισμό των περιόδων επαναφοράς. Η μεθοδολογία που αναπτύσσεται για την ανάλυση και την μοντελοποίηση των παράκτιων καταιγίδων εφαρμόζεται σε πρωτογενή κυματικά δεδομένα και όχι σε δεδομένα προσομοιώσεων. Δεδομένα 30 διαφορετικών περιοχών αναλύονται για πρώτη φορά στη Μεσόγειο θάλασσα, αλλά και γενικότερα, μελετώντας 4008 ιστορικές παράκτιες καταιγίδες για την χρονική περίοδο 1985-2019. Πιο αναλυτικά, για τον ορισμό της παράκτιας καταιγίδας χρησιμοποιούνται τα κατώφλια του ύψους κύματος, της ελάχιστης διάρκειας ενός γεγονότος και του χρονικού διαστήματος ηρεμίας που μεσολαβεί μεταξύ δύο διαδοχικών γεγονότων. Μέσω αυτών εντοπίζονται οι παράκτιες καταιγίδες σε κάθε περιοχή και στη συνέχεια εξετάζονται τα χαρακτηριστικά τους, υπολογίζοντας τη συχνότητα εμφάνισης τους, τις υπόλοιπες σημαντικές μεταβλητές (ενέργεια, ροή ενέργειας και κατεύθυνση κύματος), τα περιγραφικά τους στατιστικά στοιχεία και το σχήμα των καταιγίδων. Στη συνέχεια εξάγονται οι αντιπρόσωποι των μεταβλητών κάθε γεγονότος και ακολουθεί η μοντελοποίηση τους. Μέσα από ένα σύνολο 40 διαφορετικών συζεύξεων εξετάζονται οι βέλτιστες συζεύξεις που περιγράφουν την εξάρτηση των Η και Τ κατά τη διάρκεια μιας παράκτιας καταιγίδας και γίνεται διερεύνηση των δύο καλύτερων συζεύξεων. Για την προσομοίωση των παράκτιων καταιγίδων μιας περιοχής επεκτείνονται οι αλγόριθμοι των De Michele et al. (2007), Aas et al. (2009) και Stöber and Czado (2017) σε πέντε διαστάσεις, εφαρμόζοντας σε αυτούς τις C-Vine συζεύξεις και συγκρίνονται ως προς την αποτελεσματικότητα τους. Για τις περιόδους επαναφοράς ορίζονται οι πιο ακραίες τιμές κάθε μεταβλητής, κατασκευάζονται οι συζεύξεις δύο έως πέντε μεταβλητών (π.χ. Gumbel, elliptical, t) και C-Vine συζεύξεις τριών έως πέντε μεταβλητών, υπολογίζονται οι κοινές πιθανότητες και στη συνέχεια υπολογίζονται οι περίοδοι επαναφοράς για κάθε συνδυασμό των σημαντικών μεταβλητών των παράκτιων καταιγίδων μιας περιοχής.Η παρούσα διατριβή παρουσιάζει την ανάλυση και τη μοντελοποίηση των παράκτιων καταιγίδων για την εφαρμογή τους στο σχεδιασμό των λιμενικών και παράκτιων έργων. Ειδικότερα αναδεικνύει τη σημασία της ανάλυσης των ιστορικών καταιγίδων μιας περιοχής και την εφαρμογή της θεωρίας των συζεύξεων, και κυρίως των C-Vine συζεύξεων, για την προσομοίωση των παράκτιων καταιγίδων, τον υπολογισμό κοινών πιθανοτήτων και τον υπολογισμό των περιόδων επαναφοράς. Όλα τα παραπάνω αποτελούν σημαντικά εργαλεία αφού, βοηθούν στην καλύτερη κατανόηση και προσέγγιση των παράκτιων καταιγίδων και μπορούν να ενσωματωθούν στον τεχνικό σχεδιασμό για την ανάλυση της επικινδυνότητας των ακραίων αυτών φαινομένων στην ευστάθεια, στη λειτουργικότητα αλλά και στη βελτίωση της ανθεκτικότητας των παράκτιων κατασκευών.

A Predictive Model for Estimating Damage from Wind Waves during Coastal Storms

In recent years, climate abnormalities have been observed globally. Consequently, the scale and size of natural disasters, such as typhoons, wind wave, heavy snow, downpours, and storms, have increased. However, compared to other disasters, predicting the timing, location and severity of damages associated with typhoons and other extreme wind wave events is difficult. Accurately predicting the damage extent can reduce the damage scale by facilitating a speedy response. Therefore, in this study, a model to estimate the cost of damages associated with wind waves and their impacts during coastal storms was developed for the Republic of Korea. The history of wind wave and typhoon damages for coastal areas in Korea was collected from the disaster annual report (1991–2020), and the damage cost was converted such that it reflected the inflation rate as in 2020. Furthermore, data on ocean meteorological factors were collected for the events of wind wave and typhoon damages. Using logistic and linear regression, a wind wave damage prediction model reflecting the coastal regional characteristics based on 74 regions nationwide was developed. This prediction model enabled damage forecasting and can be utilized for improving the law and policy in disaster management.

Design and pre-assessment of NBS for coastal erosion and marine flooding: a case study.

<p>The natural reserve in Sacca di Bellocchio, Lido di Spina (Italy) is affected by frequent marine floods and intense erosive phenomena which threaten the freshwater ecosystem and biodiversity at the site. Floods and erosion are linked to the reduction of river sediment transport and a progressive ground subsidence and sea level rise. The persistence of these conditions and the future rise in sea level can expose neighboring anthropized areas to coastal risk.</p><p>This work presents the project of a nature-based solution (NBS) as a possible defense and mitigation action against coastal erosion and marine flooding along the Bellocchio beach. The NBS has been newly designed   within the European project H2020 OPERANDUM (OPEn-air laboRAtories for Nature baseD solutions to Manage Environmental risk) and consists of an artificial sand dune made of natural materials, such as sand, wood, geotextiles and geomembranes through naturalistic engineering techniques. On the new dune will then be inserted native herbaceous and shrubby vegetation. The dune design was supported by an accurate hydro-morphodynamic modeling of the site combined with data concerning the morphological structure, the erosive dynamics and the local climate.</p><p>This study discusses in detail the modeling techniques and the monitoring system that guided the design of the dune and that constitute a basis for the assessment of performance and effectiveness of any future NBS intervention at the site. The monitoring campaign is still ongoing and allows the collection of critical and updated information on the impacts of coastal storms, storm surges and flood events in the area. The dataset clearly highlights that the site morphology is constantly changing due to a multitude of factors, such as seasonality, the increasing incidence and/or intensity of coastal storms, sea level rise, etc. These rapid, and sometimes drastic, morphological changes pose a substantial challenge to NBS's design and, most importantly, to its deployment planning and timing phase.</p><p> </p>

A NATIONAL-SCALE BEACH EROSION EARLY WARNING SYSTEM FOR AUSTRALIA

Australia is a distinctly coastal-focused nation, with more than 85 percent of Australians living within the narrow coastal strip. The coast is also the major economic focus of industry, trade and tourism. Australian identity and environmental values are deeply tided to life at the coast. Around Australia there is presently no state or nationally coordinated early warning capability to alert emergency managers and residents to impending damaging impacts of coastal storms. This presentation outlines the work that is underway to design and evaluate a new national-scale beach erosion EWS system for Australia.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/2HS6HrTfxfI

MAREJADAS (COASTAL STORMS) IMPACT SCALE FOR WARNING SYSTEMS

The magnitude of the impact produced by extreme waves events on the coast (such as run-up, erosion of beaches, structure overtopping and damage) depends on the combination of the magnitude of local wave, tide level and coast features (Ciavola & Coco 2017). All these factors, considering mainly those necessary to determine the magnitude of local wave, show that the impact that can be observed by this phenomenon can present important differences in nearby coasts. In Chile, the events of July 3, 2013, August 8, 2015, and January 2016 were the most energetic of the last decades from each generation zone (Winckler et.al. 2017), those that caused considerable damage in specific places on the Chilean coast. Since these events, the term Marejadas became popular and the phenomenon calls for high interest to this day.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/YhgM2K0vHTw

Classifying compound coastal storm and heavy rainfall events in the north-western Spanish Mediterranean

The Northwest (NW) Mediterranean coastal zone is a populous and well-developed area in which the impact of natural hazards like flash floods and coastal storms can result in frequent and significant damages. Although the occurrence and impacts of such hazards have been widely covered, few studies have considered their combined impact on the region, which would result in more damage. Within this context, this study analyses the occurrence and characteristics of compound extreme events of heavy rainfall episodes (as a proxy for flash floods) and coastal storms (using the maximum significant wave height) along the Catalan coast as a paradigm of the NW Mediterranean. Two different types of events are considered: multivariate, in which the two hazards occur at the same location, and spatially compounding, in which they occur within the same limited time window and their impacts accumulate at distinct and separate locations. The analysis is regionally performed along a coastline extension of about 600 km by considering seven coastal sectors and their corresponding river catchment basins. Once the compound events are analysed, the synoptic atmospheric pressure fields are analysed to determine the prevailing weather conditions that generated them. Finally, a Bayesian network is used to fully characterise these events over the territory. The obtained results show that the NW Mediterranean, represented by the Catalan coast, has a high probability of experiencing compound extreme events (3.4 events per year). Despite the relatively small size of the study area (600 km of coastline), there are significant variations in the event characteristics along the territory, with the most frequent type being spatially compound, except in the northernmost sectors where multivariate events dominate. These northern sectors also present the highest correlation in the intensity of both hazards. Three representative synoptic situations have been identified as dominant for the occurrence of these events, with different relative importance levels of the compounding drivers (rainfall and waves) and different distributions of impacts across coastal basins. Overall, the results indicate that heavy rainfall has the more significant damage impact despite the wave damage having a larger spatial reach.