Potential implications of accelerated sea-level rise for Turkey

This study comprises a first-order evaluation of the implications of accelerated sea-level rise and some other aspects of climate change for Turkey's coastal areas. Global sea-level rise during the 20th century has been estimated between 10 and 20 cm and similar changes appear to have occurred along Turkish coasts, although available data is poor. Coastal cities cover less than 5% of the total surface area of Turkey, but they have over 30 million inhabitants and are growing rapidly. The Marmara region around Istanbul has the highest population density of all regions. At the same time, more than 60% of the Turkish Gross National Product (GNP) is produced in the coastal strip from Tekirdag to Kocaeli (along the northern shoreline of the Marmara Sea). Analysis suggests that the effects of a 1-m rise in sea level could be significant and adaptation costs substantial. This preliminary assessment suggests a capital loss of about 6% of current GNP, whereas simple protection/adaptation could cost 10% of current GNP. Continued urbanisation and tourist development will further increase exposure to sea-level rise. Currently, the consequences of sea-level rise and climate change are ignored in coastal management, and although strengthening of coastal management mechanisms is required for a number of reasons, sea-level rise and climate change should be considered an important long-term issue. To assist this, detailed case studies are recommended around Turkey's diverse coast, starting with the strategically important Istanbul area.