Rodel D. Lasco Professor University of the Philippines Climate Change Impacts and Potential Adaptation Strategies in Watersheds in the Philippines Rodel D. Lasco Professor University of the Philippines

7 Steps of Climate Impacts and Adaptations Assessment (UNEP, 1996) DEFINING PROBLEM 2 SELECT METHOD 3 TEST METHOD/SENSITIVITY 4 FORMULATE INPUTS ANDASSUMPTIONS 5 ASSESS BIOPHYSICAL AND SOCIO-ECONOMIC IMPACTS 6 ASSESS AUTONOMOUS ADJUSTMENT 7 EVALUATE ADAPTATION STRATEGIES

APF Project Example (UNEP, 2003) 1. Scope project design Engage Stake- holders 2. Assess Current Vulnerability Increase Adaptive capacity 3.Characterise Future Climate-related Risks 4. Develop Adaptation Strategy 5. Continue Adaptation Process

Water Resources

Impacts of Climate Change on Water Resources Increase in volume Decrease in streamflow Increase severity, frequency and variability Increase in soil erosion and sedimentation Increase in the demand for water

Change in Precipitation Change in Temperature (°C) Table 1. Changes in precipitation, temperature, and runoff for Angat water reservoir from three GCMs (based on 2xCO2) GCM Change in Precipitation Change in Temperature (°C) Change in Runoff CCCM UKMO GFDL -6% 3% 15% +2.0 +3.1 +2.4 -12% 5% 32% Source: Jose et al., 1996

Adaptation Strategies Increase water supply Modify vegetation Impoundment Reduce evaporation Water importation

Adaptation Strategies 2 Decrease water demand Decrease water demanding activities Behavioral change Water reuse Recycling Economic instruments

Adaptation Strategies 3 Manage supply and demand Synchronize cropping systems to match water availability Maximize multiple use of water

Supply Adaptation Demand Adaptation Table 5 Supply and demand adaptation strategies for the water resources sector of the Philippines Supply Adaptation Demand Adaptation Comprehensive watershed management Water allocation system and procedures Enhanced irrigation efficiency Low water use crops and efficient farming practices Recycling (reuse) of water Improvement of monitoring and forecasting systems for floods and droughts Water pricing policies and structures Enhanced awareness of climatic change and variability Source: Cruz, 2002

Forest resources

Impacts on Forest Resources in the Philippines most of the forest resources of the country are in watershed areas tropical forests will likely expand as temperature and precipitation increase Increased forest clearing due to: Droughts and floods Inc population and dec in arable lands Increase vulnerability to fires

T change may lead to a loss of a few species of plants and animals changes in T and precipitation may result to the outbreak of pests and diseases

Potential Adaptation Options (IPCC, 2001) Forest management used to long term decisions under uncertain future market and biological conditions Most adaptation will occur under managed forests Salvaging dead and dying timber Replanting with species better suited to new climate Planting genetically modified species Intensifying or decreasing management

Exotics vs indigenous species?

Biodiversity conservation