Status and challenges on sea level monitoring and forecasting in the Mediterranean

Transcription

1 Status and challenges on sea level monitoring and forecasting in the Mediterranean Begoña Pérez Gómez Workshop on global and regional sea level variability and change Mallorca, June 2015

2 Introduction: Mediterranean --- mediterraneus: in the middle of the land Sea level played a key role in the past: 5.96 million years ago: Messinian salinity crisis : ended with a catastrophic flood that refilled the basin in several months or two years. Sea level rise at times 10m/day area 2.5 mill km 2, coastline: 46000km one ocean gateway: 14 km wide average depth: 1500 m, deepest point: 5267m small tides

3 Introduction: Mediterranean --- mediterraneus: in the middle of the land Credits SOCIB/CLS Mean sea level variability today affected by: Evaporation exceeds precipitation and river runoff Gibraltar Strait oceanic connection, critical for the circulation and ecological evolution Complex circulation patterns Significant seasonal variations (amplitude around 20 cm)

4 Tides Very small tides due to the small connection with the Atlantic ocean M2 amplitude: M2 phase: Arabelos et al., 2011

5 Mean sea level and climate change Sea level rise around 1.2 mm/yr for the XX cent. January 1993 to June 2014 Marcos and Tsimplis (2008): Enhanced sea level rise for the 90 s (up to 5mm/yr) AVISO (altimetry data) sea level in the Eastern Mediterranean basin has risen significantly in recent years Galassi and Spada, 2014: Sea level rise at tide gauges will increase by a factor of 1-6 relative to the long-term observed rates by 2050 Credits Cnes/Legos/CLS Adloff et al., 2015: twenty first century scenarios: Changes in with respect to : SeaLevel = +34 to +49cm (thermoesteric) A 30 cm rise would flood 200 km 2 of the Nile Delta, displacing over Egyptians

6 Storm surges: Acqua alta: Venice Agravated by the subsidence Tide Monitoring and Forecast Centre of the City of Venice first used on March 24, 2008, with a sea level forecast of 110 cm above MSL (first level of alert) Extreme storms Eastern coast of Spain: December 1, 2008 Severe damage on harbours and beaches. Extreme sea levels in Barcelona tide gauge November

7 Tsunamis, seiches, rissagas: May 2003: algerian earthquake triggered a moderate tsunami causing waves close to 1m and severe damage in the Balearic Islands harbours Valencia tide gauge Ibiza tide gauge

8 Tsunamis, seiches, rissagas Maramai A., Brizuela, B., Graziani L The Euro-Mediterranean Tsunami Catalogue. 290 tsunamis since 6150 B.C. Creation of NEAMTWS (IOC/UNESCO) and Regional and National Tsunami Warning Centers

9 Status of sea level monitoring: Applications of tide gauges: Sea level related hazards becoming more important. Changes in the network

10 Status of sea level monitoring: NEAMTWS inventory (WG3): 1 sampling (and latency?) around 103 tg s in the Med More stations being installed by the NTWC s. New technologies (radar) Main gap of the sea level network: North of Africa

11 Status of sea level monitoring: Challenge: Convert measurement into information for a large and diverse variety of users

12 Status of sea level monitoring: Challenge: Need of new standards on data processing

13 Status of sea level monitoring: Challenges: Understanding altimetry and tide gauge data correlation and differences Tide gauges still critical: measurement of land motion needed, coastal impact Need of offshore pressure sensors Improve quality of altimetry near the coast

14 Existing data portals: Several data portals allow today access to sea level data from TG s. Focused on different applications and users. PSMSL Global: SONEL TG msl IOC SLSMF TG monitoring European: ROOS S: MONGOOS EMODnet General: opera. oceanography apart from national centers, National and Regional Tsunami Warning Centers.

15 Existing data portals: PSMSL (Permanent Service for Mean Sea Level): monthly means Longest time series: Trieste (1875) Marseille (1885) Venice (1909)

16 Existing data portals: PSMSL (Permanent Service for Mean Sea Level): monthly means 21 stations with more than 30 years of data

17 Existing data portals: PSMSL (Permanent Service for Mean Sea Level): monthly means TG s with data in the PSMSL; 69 of which contributing today (2013 or later)

18 Existing data portals: SONEL: Tide Gauges and GNSS stations: land movement monitored 50 TG s in the MED SEA collocated with GNSS

19 Existing data portals: MONGOOS: Operational Oceanography in the Med Sea Established in 2012 Comprises previous activities of MOON and MedGOOS Promote partnership and capacity building for GOOS in the Med Sea Link with EuroGOOS, GOOS Africa, Black Sea GOOS Access to main physical parameters (fixed stations) and forecasting models

20 Existing data portals: MONGOOS: Operational Oceanography in the Med Sea Need inclusion of more TG s in the region Data access: Centralized Link to the originator

21 Existing data portals: EMODnet portals: What is EMODnet? Network of organisations assembling marine data, metadata & data products from diverse sources within Europe in a uniform way to make marine data more (i) easily accessible, (ii) free of restrictions on use and (iii) interoperable Develop data products of common interest

22 Existing data portals: EMODnet portals: Core principles for development: Collect data once; use many times -> reduce costs Sustainable funding at a European level to maximise benefit from the efforts of individual Member States Free and unrestricted access to data and data products Build on existing efforts where data communities have already organised themselves - develop new initiatives where necessary to actively fill gaps and breakdown barriers Put the user first when developing priorities and taking decisions Develop data standards across disciplines as well as within them Process and validate data at different scales: regional, basin and pan-european Provide statements on data ownership, accuracy and precision

23 Existing data portals: EMODnet portals:

24 Existing data portals: EMODnet portals: EMODnet physics: Tide gauges, buoys, gliders, argo floats, etc. Total platforms: 5290!!

25 Existing data portals: EMODnet portals: EMODnet physics: Tide gauges: many still not included in the Mediterranean basin!

26 Sea level forecasting: Nivmar system: first storm surge model covering the whole Med Sea (2001): 2D barotropic model Forcing: wind and atm pre. TG data assimilation Tides: from TG s / LEGOS Barcelona: used daily for harbour alert system combining sea level and waves forecast

27 Sea level forecasting: Nowadays: 7 models with atmospheric pressure, available for storm surge forecast System Institution Model Nivmar Puertos del Estado HAMSOM MFC-Currents* INGV NEMO 3.2 Kassandra Med Sea ISMAR SHYFEM - WWMII Kassandra Black Sea ISMAR SHYFEM - WWMII CYCOFOS Cyprus Oc.Center OTIS POSEIDON 5 HCMR POM IBI-MFC Puertos del Estado NEMO SAMPA Puertos del Estado MITgcm

28 Sea level forecasting: 25 models WITHOUT atmospheric pressure: ocean circulation System Institution Model WMOP SOCIB ROMS PSY2, PSY3, PSY4 Mercator Ocean NEMO 3.1 POSEIDON 3 HCMR POM PREVIMER-MENOR IFREMER MARS3D WM Sub-Regional MFC OOC Oristano POM and WWMII(wave) Sicily Channel Reg sub-mfc OOC Oristano POM and WWMII(wave) Tyrrenian Sea Forecasting ENEA POM AFS INGV POM POSEIDON 7 HCMR POM

29 Conclusions and challenges Sea level related hazards demand an increasing number of tide gauge stations in the Mediterranean, with new latencies, sampling and technologies There is STILL a gap in TG data availability in the North of Africa, with important consequences for (not only) the existing NTWC s that require real time data from all the basin Sea level forecasts in the Mediterranean are no longer ignored: a significant number of operational models exist today that will require careful calibration and comparison with altimetry and tide gauges The small and enclosed dimensions of the Med Sea make difficult to get high quality data from altimetry near the coast: more research and effort needed in this topic Existing offshore pressure sensors established by the NTWC s should be available for other users in the same way the PSMSL is doing since 2014 for other regions Integration of tide gauges with altimetry and other observations (ARGO, CTD s..) becomes easier today thanks to the new data portals with free access to all information of interest for sea level studies

30 Ending with a request contribution to EMODnet and MONGOOS recently established data portals can only be done together with the the DATA PROVIDERS AND USERS: WE NEED YOUR HELP find us at: or via patrick.gorringe@eurogoos.eu And recent news of interest for Europe and the Mediterranean Sea: New EuroGOOS Task Team on Tide Gauges recently established (2015) Thank you for your attention