1. Begoña Pérez Gómez, Puertos del Estado, Spain
Tsunami detection component: discussion about the existing network
and real-time data processing
Begoña Pérez Gómez, Puertos del Estado, Spain
TsuMaMos 2014, Málaga April 9-11, 2014

2. Outline Marine network: role within TWS’s NEAMTWS overview
Spanish system: REDMAR network
Real time quality control and tsunami detection algorithm
Data interpretation and examples
Future activities
Conclusions
TsuMaMos 2014, Málaga April 9-11, 2014

3. Objectives: Marine network: role within TWS’s Tsunami confirmation
Models validation and improvement
Improvement of real-time forecasts (data assimilation)
Warning (?)
Detection of non-seismic “tsunami” events (submarine landslides, meteorological-wind waves seiches)
TsuMaMos 2014, Málaga April 9-11, 2014

4. Marine network: role within TWS’s
Operational today:
Sea level data at the coast: tide gauges
Offshore pressure (sea level) sensors: e.g. DART buoys
New technologies:
Radar HF
GPS buoys
Instrumentation of submarine telecommunication cables
TsuMaMos 2014, Málaga April 9-11, 2014

5. Offshore instrumentation:
NEAMTWS overview
Offshore instrumentation:
Plans for three DART buoys in Greece (Pylos, East and South of Crete)
Plans GPS buoys in Portugal
Pressure sensor at Antares observatory (South of Toulon, France)
Plenty of new HF radar stations are now being installed in the European coasts
But, what do we really have operational now for tsunami measurement in real-time?

6. NEAMTWS overview
TsuMaMos 2014, Málaga April 9-11, 2014

7. NEAMTWS overview
Core network of NEAMTWS: Basic minimum requirements for tsunami warning: 1-min or less sampling and latency (not fulfilled by all the stations at IOC SLSMF)
More stations needed by the NTWC: national networks encouraged to contribute for an adequate density of stations:
bilateral agreements
Communications mainly based on Internet (GPRS-ADSL), 1’;
GTS data latency (France): 6’
Meteosat DCP: now 15’ (new DCP higher rate 1’, ready soon)
TsuMaMos 2014, Málaga April 9-11, 2014

8. Spanish system: REDMAR network
36 radar tide gauges
2Hz raw data
1’ transmitted
(Internet)
1’ atm.press., wind waves and wind
Available at:
Portus:
SLSMF (IOC)
Future: NTWC’s (IGN)
One of the marine networks operated by
The Spanish Harbours (Puertos del Estado)
TsuMaMos 2014, Málaga April 9-11, 2014

9. Spanish system: REDMAR network
A multipurpose tide-gauge network
TsuMaMos 2014, Málaga April 9-11, 2014

10. Spanish system: REDMAR network Why? The Algerian earthquake tsunami:
May 2003, impact in the Balearic Islands
TsuMaMos 2014, Málaga April 9-11, 2014

11. Main element of the Portus Alert System:
Spanish system: REDMAR network
Main element of the Portus Alert System:
TsuMaMos 2014, Málaga April 9-11, 2014

12. Real Time QC and Tsunami Detection Algorithm
Today at Puertos del Estado Portus system.
Next steps: alert and data transmission to IGN (NTWC)
redundancy of communications and sensors
improve latency and access to 2Hz data
TsuMaMos 2014, Málaga April 9-11, 2014

13. Steps for Tsunami Detection Algorithm:
Real Time QC and Tsunami Detection Algorithm
Steps for Tsunami Detection Algorithm:
Quality Control
High pass filter
Configuration of thresholds
Detection Algorithm
Display and trigger a message
Several algorithms developed and published (e.g. TRANSFER project)
TsuMaMos 2014, Málaga April 9-11, 2014

14. Real Time QC and Tsunami Detection Algorithm
At Puertos del Estado (Portus system):
Basic real time QC combined with 15-min near real time quality control (splines algorithm for spikes detection)
High pass filter removing periods > 3 hours: FIR digital filter with 15 order Kaiser window:
Computation of variance evolution on a moving window of the filtered time series
TsuMaMos 2014, Málaga April 9-11, 2014

15. Real Time QC and Tsunami Detection Algorithm
TsuMaMos 2014, Málaga April 9-11, 2014

16. Real Time QC and Tsunami Detection Algorithm
TsuMaMos 2014, Málaga April 9-11, 2014

17. Data interpretation and examples
Other tsunami-like events: storms Jan-Feb 2014
Caused by
wind waves
TsuMaMos 2014, Málaga April 9-11, 2014

18. Data interpretation and examples
Other tsunami-like events: storms Jan-Feb 2014
High tide + wind waves + seiches (tsunami-like events)=
inundation
TsuMaMos 2014, Málaga April 9-11, 2014

19. Data interpretation and examples
Other tsunami-like events: storms Jan-Feb 2014
Wind waves
Tsunami-like
Oscillations
(2-4 min)
TsuMaMos 2014, Málaga April 9-11, 2014

20. Data interpretation and examples
Other tsunami-like events: meteo-tsunamis or “rissagas” in the Mediterranean
TsuMaMos 2014, Málaga April 9-11, 2014

21. Data interpretation and examples
TsuMaMos 2014, Málaga April 9-11, 2014

22. Data interpretation and examples
TsuMaMos 2014, Málaga April 9-11, 2014

23. Data interpretation and examples
Problem of real-time quality control:
TsuMaMos 2014, Málaga April 9-11, 2014

24. Data interpretation and examples
Problem of real-time quality control:
More details in the paper: Use of tide gauge data in operational oceanography and sea level hazard warning systems, Pérez et al, Journal of Operational Oceanography, 2013
TsuMaMos 2014, Málaga April 9-11, 2014

25. Future activities
Radar HF
Surface currents, potential detection of tsunamis (enough time?)
Radar HF available at Portus
system today

26. Submarine telecommunications cables
Future activities
Submarine telecommunications cables
ITU, UNESCO-IOC and WMO
established a Joint Task Force (JTF) tasked to investigate using submarine telecommunications cables for ocean and climate monitoring and disaster warning
over 80 international experts from the science, engineering, business and law communities

27. Submarine telecommunications cables
Future activities
Submarine telecommunications cables
Two reasons account for the superiority of submarine cables: they are the only technology that can transmit large amounts of information across bodies of water with low latencies (delays), and they do so at low costs.
A new generation of scientific cabled ocean observatories is emerging at a few selected sites, but there is a need and opportunity to extend observations and monitoring over much wider area of the global oceans. Submarine telecommunication cables equipped with sensors to measure key variables such as water temperature, pressure and acceleration on the ocean floor are viewed as vital to monitor climate change and to provide tsunami warnings.

28. Conclusions
Sea level data from tide gauges are today the basic operational information for the TWS’s in Europe
The short distance of tsunamigenic sources to our coast make difficult to invest on expensive offshore instrumentation
In spite of the interest on qc and automatic detection algorithms being applied to sea level / pressure data, sea level expertise and human inspection is still crucial. Sea level variability implies detailed configuration of the automatic algorithms for alerts
Inundations at the coast are not only caused by seismic events, so marine detection for a multi-hazard approach is beyond the scope of present tsunami warning systems
New technologies and already existing infrastructure may become part of the tsunami alert systems in the future (ASTARTE project, Joint Task Force, etc)
A denser network of sensors is claimed and needed for improving forecasting models
Critical need of international data exchange and availability in real-time for tsunami confirmation and eventual improvement of warnings

29. Thank you