Melting Himalayan glaciers and other climate change impacts pose a direct threat to the water and food security of more than 1.6 billion people in South Asia, according to preliminary findings of a new study financed by the Asian Development Bank (ADB). Analyzing current trends and scenarios based on projected temperature increases, the study warns that four countries in South Asia Afghanistan, Bangladesh, India and Nepal are particularly vulnerable to falling crop yields caused by glacier retreat, floods, droughts, erratic rainfall and other climate change impacts. 'South Asia's vulnerability to climate change has extremely serious implications for agriculture and therefore food security,' Kunio Senga, Director General of ADB's South Asia Department, said on Wednesday after a major climate change conference in the Nepalese capital Kathmandu. Produced by the International Food Policy Research Institute, the study, 'Addressing Climate Change in the Asia and Pacific Region: Building Climate Resilience in the Agriculture Sector', will be officially launched by ADB on the sidelines of the United Nations Framework Convention on Climate Change meeting in Bangkok in late September. The study warns that if current trends persist until 2050, the yields of irrigated crops in South Asia will decrease significantly maize (-17 percent), wheat (-12 percent) and rice (-10 percent) because of climate change-induced heat and water stress. Resulting food scarcity will lead to higher prices and reduced caloric intake across the region. Under this scenario, per capital calorie availability in 2050 will be below levels recorded in the year 2000. Almost half of the world's absolute poor live in South Asia, where they tend to depend on rain-fed agriculture and live in settlements that are highly exposed to climate variability. The study outlines a range of agricultural adaptation measures that can significantly reduce the region's vulnerability to climate change impacts. These include investments in irrigation expansion and water resource management, farm- to-market roads, and agriculture research and dissemination. 