COS 112-6
Vulnerability assessment of an island in Southern Philippines to climate change
Majority of inhabitants in island communities in the Southern Philippines live in coastal areas. In the coming decades, further development and increasing population would increase human pressures on coastal ecosystems. Beach erosion, strong waves and storm surges are the common threats to these islands. Other threats include inundation and flooding because of their low-lying setting. We assessed the vulnerability of Bongao, Tawi-Tawi (5°2′0″N 119°46′0″E), an island municipality in the Southern Philippines to climate change. We quantified vulnerability by scoring sensitivity (intrinsic geological, physical and biological characteristics of the coastal zone that make it vulnerable) of the coastal areas of Bongao to sea level rise, storm surge and wave impacts. The vulnerability scores ranged from 3 to 1 (3= high sensitivity; 2= medium sensitivity and 1= low sensitivity). Using the sensitivity scores as an index, we mapped the vulnerability of the coastal areas of Bongao island.
Results/Conclusions
The highly populated southeastern and southern coasts of the island have low seagrass and coral cover (≤20 %) and no mangrove forest; these areas have a vulnerability score of 3 or high sensitivity to storm surges, wave impacts and sea level rise. The least populated northwestern and northeastern coasts of the island have intermediate seagrass and coral cover (≤ 50%) and secondary growth mangrove forests; these areas have a vulnerability score of 2 or medium sensitivity to impacts of climate change. Given that sea level will increase in the coming years and that storms are likely to increase in frequency and strength, the natural buffers to storm surges and big waves, such as coral reefs and mangroves, should be protected and restored in Bongao island.