scholarly journals Imbricated Coastal Boulder Deposits are Formed by Storm Waves, and Can Preserve a Long-Term Storminess Record

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Rónadh Cox ◽  
Louise O’Boyle ◽  
Jacob Cytrynbaum
Keyword(s):  
Storm Waves ◽  
Boulder Deposits

scholarly journals Measuring Change Using Quantitative Differencing of Repeat Structure-From-Motion Photogrammetry: The Effect of Storms on Coastal Boulder Deposits

2019 ◽  
Vol 12 (1) ◽  
pp. 42 ◽  
Author(s):  
Timothy Nagle-McNaughton ◽  
Rónadh Cox
Keyword(s):  
Structure From Motion ◽  
Data Sets ◽  
Repeat Structure ◽  
Camera Systems ◽  
Storm Waves ◽  
Frequent Monitoring ◽  
Single Lens ◽  
Boulder Deposits

Repeat photogrammetry is increasingly the go-too tool for long-term geomorphic monitoring, but quantifying the differences between structure-from-motion (SfM) models is a developing field. Volumetric differencing software (such as the open-source package CloudCompare) provides an efficient mechanism for quantifying change in landscapes. In this case study, we apply this methodology to coastal boulder deposits on Inishmore, Ireland. Storm waves are known to move these rocks, but boulder transportation and evolution of the deposits are not well documented. We used two disparate SfM data sets for this analysis. The first model was built from imagery captured in 2015 using a GoPro Hero 3+ camera (fisheye lens) and the second used 2017 imagery from a DJI FC300X camera (standard digital single-lens reflex (DSLR) camera); and we used CloudCompare to measure the differences between them. This study produced two noteworthy findings: First, volumetric differencing reveals that short-term changes in boulder deposits can be larger than expected, and that frequent monitoring can reveal not only the scale but the complexities of boulder transport in this setting. This is a valuable addition to our growing understanding of coastal boulder deposits. Second, SfM models generated by different imaging hardware can be successfully compared at sub-decimeter resolution, even when one of the camera systems has substantial lens distortion. This means that older image sets, which might not otherwise be considered of appropriate quality for co-analysis with more recent data, should not be ignored as data sources in long-term monitoring studies.

scholarly journals Storm surges and extreme storms in Sakhalin Island and South Kuril Islands

2019 ◽  
Vol 265 ◽  
pp. 03004
Author(s):  
Georgy Shevchenko ◽  
Ekie Kato ◽  
Marina Khuzeeva
Keyword(s):  
Sea Level ◽  
Storm Surges ◽  
Coastal Areas ◽  
Sakhalin Island ◽  
Kuril Islands ◽  
Annual Variations ◽  
Storm Waves ◽  
The Impact ◽  
South Kuril Islands

Storm surges (the significant sea level rises due to a drop in surface atmospheric pressure and an increase in wind velocity during the passage of deep cyclones over the coastal areas) pose a formidable threat to the coastal settlements of Sakhalin and the South Kuril Islands. As a result of flooding of coastal areas, the impact of storm waves on the shores and coastal facilities is sharply increased. The greatest damage caused by surges on 10.11.1990 and 9.11.1995 which affected the most populated southern part of Sakhalin Island. A long-term sea level series were analyzed, recorded at 9 coastal tide gauges located on the coast of Sakhalin Island and South Kuril Islands. Estimates for the maximum heights of the storm surges and tidal level were obtained separately, as well as for the rare recurrence of the total sea level height with the probability of these individual components superposition. The maximum total height of the sea level was obtained for the Kurilsk station, where the highest storm surge was recorded. The minimum values were obtained for southwestern coast of Sakhalin Island (Kholmsk and Nevelsk stations) were tides are small. Seasonal and inter-annual variations of strong waves were analysed from the data of visual observations.

scholarly journals Damage to Seisho Bypass due to Storm Waves During Typhoon 0709

2008 ◽  
Vol 3 (5) ◽  
pp. 342-350 ◽  
Author(s):  
Takaaki Uda ◽  
◽  
Toshiro San-nami ◽  
Toshinori Ishikawa ◽  
Keyword(s):  
Submarine Canyon ◽  
Sand Transport ◽  
Field Observations ◽  
Wave Impact ◽  
The Road ◽  
Storm Waves ◽  
Sand Supply

Some 1.1 km of the Seisho Bypass along the Seisho coast was severely damaged on September 7, 2007, due to Typhoon 0709 storm waves, closing the road to traffic for emergency repairs. Damage to the highway, caused primarily through wave impact and secondarily by long-term shoreline recession due to decreased fluvial sand supply from the Sakawa River and sand loss into a submarine canyon, was investigated through field observations. A factor contributing further to shoreline recession was the obstruction of eastward longshore sand transport by the Ninomiya fishing port breakwater. Storm waves hit the coastline counterclockwise to normal to the shoreline, causing offshore and westward longshore sand transport with part of the sand transported by the longshore sand transport flowing into the submarine canyon, causing a net sand loss.

scholarly journals HEADLAND DEFENSE OF COASTS

1976 ◽  
Vol 1 (15) ◽  
pp. 81 ◽  
Author(s):  
Richard Silvester
Keyword(s):  
Fixed Point ◽  
Fixed Points ◽  
Equilibrium Shape ◽  
Rock Outcrop ◽  
Littoral Drift ◽  
Storm Waves ◽  
Long Term Changes ◽  
The Cost

Crenulate shaped bays are ubiquitous and constitute the largest proportion of coastline length. The characteristics of stable bays (i.e., no littoral drift) are known, so that realistic encroachment limits can be defined. Allowances for long term changes in direction of persistent swell and annual attack from multidirectional storm waves may have to be made. The exposure of a rock outcrop during an erosive sequence will create a new fixed point on the coast and hence a new bayed system. An existing non-stable bay can be prevented from indenting to its equilibrium shape by the construction of one or more fixed points around its periphery. Research should be conducted to minimise the cost of headlands which might start off as offshore breakwaters, even mobile units.

scholarly journals Wave climate and storm activity in the Kara sea

2020 ◽  
Author(s):  
Stanislav Myslenkov ◽  
Vladimir Platonov ◽  
Alexander Kislov ◽  
Ksenia Silvestrova ◽  
Igor Medvedev
Keyword(s):  
Interannual Variability ◽  
Pareto Distribution ◽  
Ice Cover ◽  
Wave Climate ◽  
Kara Sea ◽  
The Arctic ◽  
Storm Activity ◽  
Storm Waves ◽  
Ice Conditions

Abstract. Recurrence of extreme wind waves in the Kara Sea strongly influences the Arctic climate change. The paper presents the analysis of wave climate and storm activity in the Kara Sea based on the results of numerical modeling. A third-generation wave model WaveWatchIII is used to reconstruct wind wave fields on an unstructured grid with a spatial resolution of 15–20 km for the period from 1979 to 2017. The mean and maximum wave heights, wavelengths and periods are calculated. The maximum significant wave height (SWH) for the whole period amounts to 9.9 m. The average long-term SWH for the ice-free period does not exceed 1.3 m. The seasonal variability of the wave parameters is analyzed. The interannual variability of storm waves recurrence with different thresholds (from 3 to 7 m) was calculated. A significant linear trend shows an increase in the storm wave frequency for the period from 1979 to 2017. A double growth in the reccurence was observed for cases with an SWH more than 3–5 m from 1979 to 2017. The local maximum of the storm waves more than 3–4 m was observed in 1995, and the minimum in 1998. The maximum value (four cases) of the number of storms with an SWH threshold 7 m is registered in 2016. The frequency of wind speeds and ice conditions contributing to the storm waves formation were analyzed. It is shown that trends in the storm activity of the Kara Sea are primarily regulated by the ice. If the ice cover decreases in the southern part of the sea that leads to the increase of the number of events only with SWH threshold more than 3–4 m. If in the entire sea the ice cover decreases that leads already to increase of the extreme storms. The frequency of strong and long-term winds has high interannual variability and a weak positive trend. The analysis of distribution functions of the storm events with an SWH more than 3 m was carried out. Six different sectors of the Kara Sea were analyzed to reveal spatial differences. A comparison of the different distribution laws showed that the Pareto distribution is in the best agreement with the data. Up to 99 % of the points are described by this distribution. However, the extreme events with an SWH more than 6–7 m deviate from the distribution, and their probability is approximately twice as less as that predicted by the Pareto distribution. Presumably, this deviation is caused by the combined impact of rare wind speed frequencies and anomalies of the sea ice conditions.

scholarly journals FLORIDA COASTAL DATA NETWORK

1980 ◽  
Vol 1 (17) ◽  
pp. 25 ◽  
Author(s):  
Gary Howell
Keyword(s):  
Field Measurements ◽  
Coastal Engineering ◽  
Army Corps ◽  
Intermediate Water ◽  
California Department ◽  
Data Network ◽  
Storm Waves ◽  
Wave Measurement ◽  
Waves And Tides

The application of wave and tide data to coastal engineering problems has been demonstrated frequently by university and government research organizations. However, problems faced by practicing coastal engineers are often solved without recourse to such data, since it is frequently not available for the required location. The high cost and low reliability of long term wave measurement is the primary factor limiting the wider application of analysis techniques requiring wave energy and wave direction parameters. In order to improve this situation several organizations, notably the Army Corps of Engineers, Coastal Engineering Research Center (CERC), Peacock (1974), and the California Department of Navigation and Ocean Development, Seymour (1976), have employed advanced electronics and computer techniques to reduce the cost of wave measurement. The Florida Coastal Data Network (CDN) is a similar effort which due to the special problems of Florida wave climate has employed advanced instrumentation not only to reduce cost, but to provide additional capability. Like other tropical and sub-tropical regions, Florida's coastal environment is characterized by relatively infrequent but severe tropical storms. In many coastal engineering applications, the specification of the hurricane-associated storm surge and storm waves will be the major design criteria. The Florida CDN was created in order to provide field measurements of waves and tides year-around as well as during hurricanes. A measurement program of this nature must respond to both the immediate needs of practicing engineers as well as to research needs. Since it is unrealistic to hope for measurements of hurricane conditions at every location, the long term goal of research is to produce better models of storm waves and surge. Field measurements are required to assist in the formulation and validation of models. In the near term, actual measurements of both normal and severe waves and tides are the most reliable design input for the shallow and intermediate water depths.

Therapy and prevention for mental health: What if mental diseases are mostly not brain disorders?

2019 ◽  
Vol 42 ◽  
Author(s):  
John P. A. Ioannidis
Keyword(s):  
Mental Health ◽  
Mental Disease ◽  
Brain Disorders ◽  
Social Stressors ◽  
Labor Education ◽  
Mental Diseases ◽  
Long Term Follow Up ◽  
Political Decisions

AbstractNeurobiology-based interventions for mental diseases and searches for useful biomarkers of treatment response have largely failed. Clinical trials should assess interventions related to environmental and social stressors, with long-term follow-up; social rather than biological endpoints; personalized outcomes; and suitable cluster, adaptive, and n-of-1 designs. Labor, education, financial, and other social/political decisions should be evaluated for their impacts on mental disease.

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