Sea level data for the Iberian Peninsula Coastal

Sea level data for the Iberian Peninsula

Coastal erosion is a real problem in Portugal: sea level changes? “Accelerated sea level rise”? Francelos: 31 dec 1998

Tectonic framework: Recent mountains in the periphery of mini Iberian plate

Neogene compression

Earthquakes in iberia

PSMSL in 2002 105 L'ESTARTIT BARCELONA VALENCIA ALICANTE II ALICANTE I CARTAGENA ALMERIA MALAGA II MALAGA TARIFA ALGECIRAS BONANZA CADIZ III CADIZ II GIBRALTAR LAGOS SINES SETROIA LISBON CASCAIS AVEIRO LEIXOES VIANA VIGO LA CORUNA III LA CORUNA I SANTANDER I BILBAO PASAJES 35 90 30 Portuguese stations 75 25 60 20 45 30 15 5 RLR sea level (mm/year) 10 Number 15 0 0 -5 -15

Is sea level rise accelerating? Many people says so. Is it true?

Many PSMSL stations are not updated

-2 -7 -12 AVEIRO Portuguese coast HUELVA ALGECIRAS Trend Years 22 L'ESTARTIT 7 BARCELONA 21 SAGUNTO 11 VALENCIA 20 GANDIA ALICANTE II 40 ALICANTE I 9 CARTAGENA 10 ALMERIA 2 22 ALMERIA 9 MOTRIL 2 22 MALAGA II 72 MALAGA 5 GIBRALTAR 5 ALGECIRAS B 7 ALGECIRAS 2 55 TARIFA 2 73 TARIFA CADIZ III 112 CADIZ II 15 18 BONANZA 14 LAGOS 21 SINES 21 SETROIA LISBON 8 CASCAIS 22 LEIXOES 43 VIANA 18 VIGOI II 73 VIGO 22 VILLAGARCIA LA CORUNA III 19 LA CORUNA II 12 FERROL 2 73 LA CORUNA I 22 GIJON II 16 SANTANDER II 22 SANTANDER III 8 SANTANDER I 3 BILBAO PASAGES Iberia: trends vs. length of series 109 91 70 59 53 45 38 25 7

Iberia, in short series: great irregularities in the trends 125 100 75 50 average 25 -15. 00 -10. 00 -5. 00 0 0. 00 5. 00 10. 00 15. 00

Iberia series >18, 6 yr Average BONANZA CADIZ III LA CORUNA III BILBAO LA CORUNA I VIGOI II SANTANDER I VIGO SANTANDER III LAGOS SETROIA CADIZ II CASCAIS GIJON II TARIFA LA CORUNA II LEIXOES AVEIRO -2. 00 -1. 00 0. 00 1. 00 Station 2. 00 3. 00 Trend Iberia>18 yrs 1, 92 Iberia>60 yrs 1, 63 Atlantic>18 yrs 1, 89 4. 00 5. 00 6. 00

Cascais: PSMSL data 7200 7150 7100 7050 7000 6950 6900 6850 6800 6750 6700 1880 1900 1920 1940 1960 1980

Sea leval station monitoring facility

Sagres Station: data and graphs (every minute)

DATA AT CASCAIS IS NOT ACTUALIZED

With the data I was able to get one can make this kind of graphs:

Carlos Antunes site (FCUL)

It was used an uplift of 0, 5 mm/yr

Secular variation of sea level at Cascais

To understand the influence of earth movements: GPS stations

GPS Cascais: vertical velocity

GPS Lagos: vertical velocity

RSL trends (PSMSL)

Vertical velocities vs latitude: and around Iberia

Absolute sea level trends

Conclusions 1: 1. Most of the places out of Scandinavia are subsiding. This augments RSL trends 2. The exception: recent mountain ranges in the limits of Iberia (Pyrenees and Baetics) 3. The “absolute sea level” changes (discounting on earth movements) are available only for 5 locations in Iberia 4. 4 of them are under 1 mm/yr of absolute (eustatic/steric) sea level rise

Going back to the beginning: which are the causes of coastal erosion?

The unfortunate “Titanic” case

Any interference on littoral drift has big consequences Littoral drift

Vcoastal Coastal evolution in the last 50 years: northern Portugal

Aveiro lagoon (Centre Portugal) N Littoral drift

Sediments retention by dams: Northern Portugal

Conclusions 2: 1. Coastal erosion has very little to do with sea level change (10%? ) 2. Anthropic interventions have a lot to do with it 3. RSL: average >18, 6 yr: 1, 92 4. Absolute SL rise <1 mm/yr 5. Sea level rise as primary factor for coastal erosion Is simply FALSE

Thanks for your attention!