economic data scenarios to the national and sub-national scales for a global climate impact assessment of future food scarcity, water stress, exposure to malaria, coastal flood risk and wetland loss and terrestrial ecosystems. They suggested that urban and rural growth rates be considered. Two limitations of the SRES scenarios were identified: first, “there are considerable difficulties involved in moving from the scale at which the SRES scenarios were produced (11–13 world regions) to the much finer spatial resolution required by impacts models. A number of rather major assumptions had to be made, most specifically that all parts of a region would change at the same rate: this was applied to population, GDP and land cover” and; second, “whilst the SRES land cover trends are consistent with the narrative storylines, they are inconsistent with recent trends. Under none of the storylines is there a sustained continued deforestation, for example, and crop areas decrease under all of them”. Ziervogel and Eriksen (2010) offer a framework for assessing the impacts of climate change on food security. They discussed linkages between climate change (temperature, precipitation, and extreme weather events), food security (availability, accessibility, stability and utilization) and its drivers (cycles for consistency, agricultural management, socio-economic variables, demographic change, cultural and political variables and science and technology). Figure 4. Linkages between climate change and food security Climate change Food security drivers Food security Temperature Precipitation Extreme weather events Cycles for consistency Agricultural management Socio-economic variables Demographic change Cultural and political variables Science and technology Availability Accessibility Stability Utilization Source: Chart taken from Ziervogel and Eriksen, 2010 According to them, the key issues that should be addressed to respond to food insecurity and managing transitions or innovation in cropping system include: chronic poverty, functioning markets, farmer attitudes toward managing risks, and reforming or improving the institutions responsible for managing food and agricultural systems. In the Philippines, the Department of Agriculture expects the following impacts of different climatic events as shown in the table 2: Table 2. Expected impacts of global climate change in the Philippine agricultural sector No 1 Climatic Events Rainfall Impact Decrease by 20 percent, but increase in intensity. Increase Source/Assumptions  IPCC 2007  Godilano, E.C. 2005  FAO (2006) CBMS-FAO | 14