THE GREENHOUSE EFFECT

Transcription

1 The dilemma of the illegibility of state visions: The Greek Coastal Legislation CONTENT OF THE PREENTATION 1. CLIMATE CHANGE AND PREDICTION Efstratios Doukakis Associate Professor NTUA National Technical University of Athens chool of Rural and urveying Engineering Marine ciences 2.THE UE OF THE EAHORE AND BEACH ZONE 3. MODEL TO TUDY HORELINE CHANGE 4. TUDY OF THE TRATEGIC RETREAT IN GREECE 5. REULT AND CONCLUION FIG WORKING WEEK, ATHEN 22-27, 2004 THE GREENHOUE EFFECT IMPACT OF TEMPERATURE INCREAE HITORICAL CONCENTRATION OF CO 2 AND METHANE Variations of the Earth s surface temperature during the last millennium and projections in the 21 st century IN THE LAT 7 YEAR : 10% IN CO 2 CONCENTRATION! 1

2 TEMPERATURE RIE CENARIO OVER THE 21 st CENTURY o C 0.8 o C LR: cm THE UE OF EAHORE AND BEACH ZONE the seashore limit ends up where the usual but maximum waves run up the beach the seashore zone is the buffer zone of a coastal area absorbing the wave impact energy and accommodates the high tidal waters the beach zone extends 50 m from the landward limit of the seashore zone no private construction is permitted (in the seashore and beach zones). They have to remain free for public use, defense etc. LEGIBLE GREEK TATE VIION (?) : THE COATAL LEGILATION (Law 2971/2001) artcl. 12 : in case of beach erosion, hard protection measures can be exercised by the threatened owner. The structures are approved by the state and belong to it. there is not a single reference of re-delimitating the public zone (seashore and beach zones) in the future by any reason (e.g. climatic) The sustainability principle is absent! TATIC PART DYNAMIC PART AN INTEGRATED MODEL ETIMATING HORELINE CHANGE MUT INCLUDE: INUNDATION CONCEPT EROION CONCEPT HITORICAL RETREAT TRONG WIND EFFECT LOCAL CHARACTERITIC (e.g. sand removal, coral reefs) models measurements INUNDATION DUE TO EA LEVEL RIE ea level after rise Initial sea level BRUUN RULE OF EROION FOR ANDY BEACHE (static model) B - A D [retreat] [retreat] = (A B) / D 2

3 ΑΙΓΙΑΛΟΣ 2050 ΜΕ ΑΝ Ο Ο 0,5m ΑΙΓΙΑΛΟΣ 2100 ΜΕ ΑΝΟ Ο 1m THE HITORICAL RETREAT PRINCIPLE Rate of change = 16 m/year the studied regions IMPACT OF CLIMATE CHANGE ON THE EAHORE ZONE DELIMITATION : RHODO ILAND TUDY AREA 2050 EAHORE 2100 EAHORE KO ILAND M m eashore in m eashore in EAHORE HOTEL IMPACT OF CLIMATE CHANGE ON THE EAHORE ZONE DELIMITATION : KO ILAND TUDY AREA HORELINE IN 1932 HORELINE IN 1978 VARTHOLOMIO AFANDOU TIGAKI KARDAMAINA AMMOGLOA horeline Length (Km) hore type Undeveloped Heavily Undeveloped emi-developed Hotel developed Coastal slope (%) EAHORE IN 1978 Geom/hology andy beach andy beach andy beach andy beach andy beach 50 m for the beach zone 105 m 235 m HOTEL EAHORE IN 2050 EAHORE IN 2100 Relative LR (mm/yr) Historical retreat (m) [period] [ ] [ ] [ ] [ ] [ ] Total retreat (m) um of impacts LR = 0.5m Total retreat (m) um of impacts LR = 1.0m

4 VARTHOLOMIO AFANDOU TIGAKI KARDAMAINA AMMOGLOA eashore displacement LR = 0.5m The setback line principle for the i th -year width of seashore and beach zones eashore displacement LR = 1.0m ML in i- years ML today shoreline shoreline estimated total retreat (inundationerosionhistorical retreat) in i-years where ER i HR i α β FORMULATION OF THE ETBACK LINE I i B i = I i [ ER i HR i ] i [α β] : the inundation displacement due to LR (in the i- th year) : the local erosion rate/y : the local historical retreat/y as projected in the future : the width on the seashore and beach zone today i : the number of years of the applied policy ML in 50y ML today PRIMARY ETBACK LINE ML in 100y ECONDARY ETBACK LINE PECIAL BUILDING CODE NO CONTRUCTION RECOMMENDATION FOR LEGIBLE TATE VIION CALCULATION OF PRIMARY AND ECONDARY ETBACK LINE VARTHOLOMIO AFANDOU TIGAKI KARDAMAINA AMMOGLOA Primary etback Line (m) econdary etback Line (m) CONCLUION AND RECOMMENDATION 1. All five regions examined will exercise shoreline retreat from 30 to 100 m (middle climate changes scenario). The seashore and beach zones will retreat accordingly. 2. To prevent new future construction in private property, primary setback lines must be introduced and extend inland to the width of the estimated shoreline retreat plus the width of both seashore and beach zones under middle climate changes scenario. 3. The secondary setback lines will add up a further zone beyond the primary setback lines which will include the pessimistic climate changes scenario. In the secondary setback zone special building codes should be introduced. 4. The Greek state s visions for coastal development via the new legislation (2001) do not support legible visions because sustainability is absent. And no matter how likely the hazard, it will not be serious unless the consequences are serious 4

5 Thus, if the state wants to have legible visions, a flexible institutional and legislative setting should call for ADAPTATION due to climate change impacts on the coastal zone E T B A C K L I N E 5