ALBERT

Description: The NEAM Tsunami Hazard Model 2018 (NEAMTHM18) is a probabilistic hazard model for tsunamis generated by earthquakes. It covers the coastlines of the North-eastern Atlantic, the Mediterranean, and connected seas (NEAM). NEAMTHM18 was designed as a three-phase project. The first two phases were dedicated to the model development and hazard calculations, following a formalized decision-making process based on a multiple-expert protocol. The third phase was dedicated to documentation and dissemination. The hazard assessment workflow was structured in Steps and Levels. There are four Steps: Step-1) probabilistic earthquake model; Step-2) tsunami generation and modeling in deep water; Step-3) shoaling and inundation; Step-4) hazard aggregation and uncertainty quantification. Each Step includes a different number of Levels. Level-0 always describes the input data; the other Levels describe the intermediate results needed to proceed from one Step to another. Alternative datasets and models were considered in the implementation. The epistemic hazard uncertainty was quantified through an ensemble modeling technique accounting for alternative models’ weights and yielding a distribution of hazard curves represented by the mean and various percentiles. Hazard curves were calculated at 2,343 Points of Interest (POI) distributed at an average spacing of ∼20 km. Precalculated probability maps for five maximum inundation heights (MIH) and hazard intensity maps for five average return periods (ARP) were produced from hazard curves. In the entire NEAM Region, MIHs of several meters are rare but not impossible. Considering a 2% probability of exceedance in 50 years (ARP≈2,475 years), the POIs with MIH 〉5 m are fewer than 1% and are all in the Mediterranean on Libya, Egypt, Cyprus, and Greece coasts. In the North-East Atlantic, POIs with MIH 〉3 m are on the coasts of Mauritania and Gulf of Cadiz. Overall, 30% of the POIs have MIH 〉1 m. NEAMTHM18 results and documentation are available through the TSUMAPS-NEAM project website (http://www.tsumaps-neam.eu/), featuring an interactive web mapper. Although the NEAMTHM18 cannot substitute in-depth analyses at local scales, it represents the first action to start local and more detailed hazard and risk assessments and contributes to designing evacuation maps for tsunami early warning.

Description: The complexity of coseismic slip distributions influences the tsunami hazard posed by local and, to a certain extent, distant tsunami sources. Large slip concentrated in shallow patches was observed in recent tsunamigenic earthquakes, possibly due to dynamic amplification near the free surface, variable frictional conditions or other factors. We propose a method for incorporating enhanced shallow slip for subduction earthquakes while preventing systematic slip excess at shallow depths over one or more seismic cycles. The method uses the classic k−2 stochastic slip distributions, augmented by shallow slip amplification. It is necessary for deep events with lower slip to occur more often than shallow ones with amplified slip to balance the long-term cumulative slip. We evaluate the impact of this approach on tsunami hazard in the central and eastern Mediterranean Sea adopting a realistic 3D geometry for three subduction zones, by using it to model ~ 150,000 earthquakes with Mw from 6.0 to 9.0. We combine earthquake rates, depth-dependent slip distributions, tsunami modeling, and epistemic uncertainty through an ensemble modeling technique. We found that the mean hazard curves obtained with our method show enhanced probabilities for larger inundation heights as compared to the curves derived from depth-independent slip distributions. Our approach is completely general and can be applied to any subduction zone in the world.

Description: Full integration of new data types into Indonesian Tsunami Early Warning System (InaTEWS) is among the enhancements being pursued at BMKG. Leveraging on external projects and partnership Real-Time Precise Point Positioning (RT-PPP) data from BIG have been integrated in the processing chain at BMKG. This GNSS data product has the potential contribute to faster and more accurate scenario selection and validation in case of large tsunamigenic events. Real-time waveforms displacement obtained with the method of Precise Point Positioning with Regional Augmentation correction (PPP-RA) and Precise Point Positioning with Ambiguity Resolution of the RT-PPP-Client, is thus acquired in SeisComP via a dedicated seedlink plugin developed within the project of Early Warning and Rapid ImpaCt Assessment (EWRICA) in the Mediterranean. Once integrated into SeisComP precise point positioning time series are integrated into the processing pipeline of the BMKG. We have successfully integrated RT-PPP processed by Geospatial Information Agency (BIG) into InaTEWS which is managed by the Meteorological, Climatological, and Geophysical Agency (BMKG). Next, waveforms will be used to improve and speed-up the earthquake parameter determination for large tsunamigenic events.

Description: Interoperability of data and products among disciplines is becoming a key aspect within the scientific community to allow the optimal integrated exploitation of data, taking advantage of modern real-time work-flows using also AI techniques.Within the EWRICA project, aiming at creating robust local ground motion models shortly after an earthquake to assess secondary effects such as tsunamis and landslides, one of the tasks focussed on integration of near-field seismo-geodetic data into real-time source inversion. To enable this task, Real-Time Precise Point Positioning (RT-PPP) data have been converted to miniSEED records on the fly by using a tailored plugin for SeisComP developed within the project. The real-time data in GFZ Displacement Real-Time (GDRT) format have been mapped to miniSEED channels as described in the SeisComP documentation [1]. The initial mapping has been defined considering also one additional use case implemented in the TURNkey project where RT-PPP data were generated from a newly developed standalone instrument. RT-PPP has been integrated in the data flow and sent out to clients via seedlink for processing in the known data and metadata format enabling faster and improved assessment of seismic moment, hypocentre and rupture kinematics.In this presentation we introduce the gdrt_plugin released for the first time in June 2022 with the SeisComP v5.0.0 [2], we outline the initial process of mapping the GNSS products to existing data and metadata formats and would welcome discussions about further integration in seismology through the FDSN.[1] https://www.seiscomp.de/doc/apps/seedlink.html#seedlink-sources-gdrt-label[2] https://github.com/SeisComP/seiscomp/releases/tag/5.0.0