141 Climate Change and Biodiversity in the Philippines Florencia B. Pulhin and Rodel D. Lasco 8 Climate Change and Biodiversity in the Philippines: Potential Impacts and Adaptation Strategies THE PHILIPPINES AND CLIMATE CHANGE Physical and Ecological Features The Philippines is an archipelagic country composed of 7,107 islands. It generally lies between 116° 40' and 126° 34' E longitude, and 4° 40' and 21° 10' N latitude. It is bounded on the southwest by Borneo, on the north by Taiwan, on the south by Moluccas and Sulawesi, and on the east by Palau. The Philippines covers a total of 30 M ha which is almost equally divided between forest lands (15.9 M ha) and alienable and disposable (A&D) lands (14.1 M ha). Of the classified forest lands, 7.2 M ha are forests, 4 M ha are open forests, 2.6 M ha are closed forests, 0.3 M ha are plantations, and 0.2 M ha are mangroves. In terms of soil types, there are 11 general categories based on the United Nations Food and Agriculture Organization (UN FAO) classification. The categories are: cambisols, gleysols, fluvisols, arenosols, regosols, luvisols, acrisols, andosols, phaeozems, nitisols, and kastanozems. Acrisols and cambisols are the most common types of soil present in many areas of the country as they cover 12 M ha and 8 M ha, respectively. Topography is varied in the Philippines. The highest point is in Mt. Apo, with an elevation of 2,954 m asl. Lowlands are located in Cagayan Reproduced from Moving Forward: Southeast Asian Perspectives on Climate Change and Biodiversity edited by Percy E. Sajise, Mariliza V. Ticsay and Gil C. Saguiguit, Jr. (Singapore: Institute of Southeast Asian Studies, 2010). This version was obtained electronically direct from the publisher on condition that copyright is not infringed.No part of this publication may be reproduced without the prior permission of the Institute of Southeast Asian Studies. Individual articles are available at 142 Florencia B. Pulhin and Rodel D. Lasco Valley and the central plains of Luzon, Cotabato, the Davao-Agusan valleys, and in Negros and Panay. Based on rainfall distribution, there are four types of climate existing in the Philippines: Type I, Type II, Type III, and Type IV. Climatic Type I is characterized by two pronounced seasons (dry and wet). Climatic Type II has no dry season but has a very pronounced rainfall from November to January. Climatic Type III is somehow in between Climatic Types I and II but is more similar to the Type I climate. It has a relatively short dry season which lasts for one to three months only. In Type IV climate, rainfall is more or less evenly distributed throughout the year. In general, the Philippines is characterised by high temperatures because of its tropical location and surrounding bodies of water. The average annual temperature in the Philippines is around 26.6 0 C, with a mean maximum temperature of 28 0 C, and a mean minimum temperature of 25.80 C. Rainfall distribution in the Philippines varies from one region to another. The mean annual rainfall range is from 965 mm to 4,064 mm. Relative humidity in the country is very high, even going as high as 85 per cent during September. Despite the very small land area, the Philippines has a high population. As of 2000, total population was pegged at 76.5 M, at a population density of 255/km2 . During 1990-2000, the annual population growth rate is at 2.34 per cent. Observed Climate Trends, Variability and Extreme Events Similar to the trend observed in the global mean temperature, the mean annual temperature in the Philippines also increases over time. From 1951 to 2006, records showed that warming occurred in the country (Figure 8.1). In terms of rainfall, a generally increasing trend on annual rainfall amounts and number of rainy days during the wettest and driest years, per decade, was observed (Perez 2007). Likewise, the occurrence of ENSO events was observed to become more frequent since 1980. For instance, from 1982 onwards, strong El Niño events occurred every five years (1982-1983, 1987-1988, 1992-1993, 19971998