This paper serves as an input for the thematic, regional and political processes of the 5th World Water Forum and focuses on the challenges related to water, climate change and food security. Recent publications related to the anticipated impacts of climate change on water and agriculture are comprehensive, but a global analysis of specific impacts remains limited.

Global climate change has resulted primarily from the accumulation of carbon dioxide (CO2) and other greenhouse gases
(GHGs) in the atmosphere over the last 150 years. However, recent studies indicate that, on average, 40 per cent of the potential warming by GHGs is being masked by certain aerosols (and aerosol-cloud interactions) that increase the reflection of sunlight.