34 research outputs found
Long Wave Dynamics along a Convex Bottom
Long linear wave transformation in the basin of varying depth is studied for
a case of a convex bottom profile in the framework of one-dimensional shallow
water equation. The existence of travelling wave solutions in this geometry and
the uniqueness of this wave class is established through construction of a 1:1
transformation of the general 1D wave equation to the analogous wave equation
with constant coefficients. The general solution of the Cauchy problem consists
of two travelling waves propagating in opposite directions. It is found that
generally a zone of a weak current is formed between these two waves. Waves are
reflected from the coastline so that their profile is inverted with respect to
the calm water surface. Long wave runup on a beach with this profile is studied
for sine pulse, KdV soliton and N-wave. Shown is that in certain cases the
runup height along the convex profile is considerably larger than for beaches
with a linear slope. The analysis of wave reflection from the bottom containing
a shallow coastal area of constant depth and a section with the convex profile
shows that a transmitted wave always has a sign-variable shape.Comment: Submitted to Journal of Fluid Mechanic
Towards the new Thematic Core Service Tsunami within the EPOS Research Infrastructure
Tsunamis constitute a significant hazard for European coastal populations, and the impact of tsunami events worldwide can extend well beyond the coastal regions directly affected. Understanding the complex mechanisms of tsunami generation, propagation, and inundation, as well as managing the tsunami risk, requires multidisciplinary research and infrastructures that cross national boundaries. Recent decades have seen both great advances in tsunami science and consolidation of the European tsunami research community. A recurring theme has been the need for a sustainable platform for coordinated tsunami community activities and a hub for tsunami services. Following about three years of preparation, in July 2021, the European tsunami community attained the status of Candidate Thematic Core Service (cTCS) within the European Plate Observing System (EPOS) Research Infrastructure. Within a transition period of three years, the Tsunami candidate TCS is anticipated to develop into a fully operational EPOS TCS. We here outline the path taken to reach this point, and the envisaged form of the future EPOS TCS Tsunami. Our cTCS is planned to be organised within four thematic pillars: (1) Support to Tsunami Service Providers, (2) Tsunami Data, (3) Numerical Models, and (4) Hazard and Risk Products. We outline how identified needs in tsunami science and tsunami risk mitigation will be addressed within this structure and how participation within EPOS will become an integration point for community development
Towards the new Thematic Core Service Tsunami within the EPOS Research Infrastructure
Tsunamis constitute a significant hazard for European coastal populations, and the impact of tsunami events worldwide can extend well beyond the coastal regions directly affected. Understanding the complex mechanisms of tsunami generation, propagation, and inundation, as well as managing the tsunami risk, requires multidisciplinary research and infrastructures that cross national boundaries. Recent decades have seen both great advances in tsunami science and consolidation of the European tsunami research community. A recurring theme has been the need for a sustainable platform for coordinated tsunami community activities and a hub for tsunami services. Following about three years of preparation, in July 2021, the European tsunami community attained the status of Candidate Thematic Core Service (cTCS) within the European Plate Observing System (EPOS) Research Infrastructure. Within a transition period of three years, the Tsunami candidate TCS is anticipated to develop into a fully operational EPOS TCS. We here outline the path taken to reach this point, and the envisaged form of the future EPOS TCS Tsunami. Our cTCS is planned to be organised within four thematic pillars: (1) Support to Tsunami Service Providers, (2) Tsunami Data, (3) Numerical Models, and (4) Hazard and Risk Products. We outline how identified needs in tsunami science and tsunami risk mitigation will be addressed within this structure and how participation within EPOS will become an integration point for community development.publishedVersio
Towards the new Thematic Core Service Tsunami within the EPOS Research Infrastructure
publishedVersio
Insights on the source of the 28 September 2018 Sulawesi tsunami, Indonesia based on spectral analyses and numerical simulations
The 28 September 2018 Sulawesi tsunami has been a puzzle because extreme deadly tsunami waves were generated
following an Mw 7.5 strike-slip earthquake, while such earthquakes
are not usually considered to produce large tsunamis. Here, we
obtained, processed and analyzed two sea level records of the
tsunami in the near-field (Pantoloan located inside the Palu Bay)
and far-field (Mamuju located outside the Palu Bay) and conducted
numerical simulations to shed light on the tsunami source. The two
tide gauges recorded maximum tsunami trough-to-crest heights of
380 and 24 cm, respectively, with respective dominating wave
periods of 3.6-4.4 and 10 min, and respective high-energy wave
duration of 5.5 and [14 h. The two observed waveforms were
significantly different with wave amplitude and period ratios of
*16 and *3, respectively. We infer tsunamigenic source dimen19
sions of 3.4–4.1 km and 32.5 km, for inside and outside of the Palu
Bay, respectively. Our numerical simulations fairly well repro21
duced both tsunami observations in Pantoloan and Mamuju; except
for the arrival time in Mamuju. However, it was incapable of
reproducing the maximum reported coastal amplitudes of 6–11 m.
It is possible that these two sources are different parts of the same tectonic source. A bay oscillation mode of *85 min was revealed
for the Palu Bay through numerical modeling. Actual sea surface disturbances and landslide-generated waves were captured by two
video recordings from inside the Palu Bay shortly after the earthquake. It is possible that a large submarine landslide contributed to
and intensified the Sulawesi tsunami. We identify the southern part of the Palu Bay, around the latitude of -0.82o
S, as the most likely location of a potential landslide based on our backward tsunami ray tracing analysis. However, marine geological data from the Palu Bay are required to confirm such hypothesis
Kaya gazının toplumsal kabulüne bilginin etkisi.
Social acceptance is critical to the market penetration of new products and technolo-gies as well as the successful implementation of policies, including those concerning energy demand. The hydraulic fracturing technique employed in the development of shale gas has been followed by controversy and this has resulted in the emergence of heterogeneity in attitudes towards the process. This thesis proposes a model for understanding the acceptance of shale gas development. The proposed model encom-passes the factors: perceived benefits, risks and costs, procedural and distributional fairness, trust, outcome efficacy, problem perception, knowledge and experience. The study then explores the impact of information provision from different sources (the government, the industry, environmental NGOs and scientists) and of different con-tent (scientific and non-scientific) on acceptance. A one-way ANOVA suggests that a significant difference between the means of the acceptance of shale gas development close to one’s house exists among the control group and the group that received in-formation from scientists. However, an overall evaluation of the model through the partial least squares technique reveals that apart from that between experience and knowledge, information provision does not alter the relationships among the factors that impact the acceptance of shale gas development significantly. For the experience factor, the results indicate that experience has a strong positive impact on knowledge for the control group only. This is crucial in that it underlines that selecting an ade-quate means of communication between relevant actors and the society could break the utilization of previous experience to construct a knowledge base.M.S. - Master of Scienc
Tsunami initial profile and maximum runup through earthquake source parameters
The 1992 September 1 Nicaragua tsunami manifested itself with an initial shoreline recession, resulting in a fundamental change in approach to define the initial waveform of tsunamis from a solitary wave to an N-wave. Here, we first fit N-wave profile to seafloor deformation for a large set of earthquake scenarios, assuming that the seafloor deformation resulting from an earthquake instantaneously transfers to the sea surface. Then, relating the N-wave parameters to the earthquake source parameters, we express the initial tsunami profile in terms of the earthquake source parameters. Further, we calculate the maximum tsunami runup through earthquake source parameters and test our results against field runup measurements for several events, observing good agreement
The Impact of Information Provision on the Social Acceptance of Shale Gas Development: A Review-Based Inclusive Model
Social acceptance is critical to the market penetration of new products and technologies as well as the successful implementation of policies, including those concerning energy demand. The hydraulic fracturing technique employed in the development of shale gas has been followed by controversy and this has resulted in the emergence of heterogeneity in attitudes toward the process. This review-based perspective surveys selected contributions of psychology to the literature on social acceptance. While not comprehensive, it aims to identify the factors that determine the acceptance of shale gas development. The proposed model for understanding acceptance encompasses the factors: perceived benefits, risks and costs, procedural and distributional fairness, trust, outcome efficacy, problem perception, knowledge and experience. The study then discusses adequate means of modulating distinguished responses to the same impulse and proposes information provision as an effective methodology. This has become a viable option because survey data and numerous opinion polls have underlined the deficiency of knowledge and the lack of a clear understanding of the risks associated with and benefits to be derived from shale gas development. Moreover, unlike experience, that is much more difficult to regulate, knowledge provides us with three channels namely the source, content and means of communication that allow for spatial divergences in policymaking