I get The Guardian weekly and, over recent months, it has run an excellent serious of articles on global water (especially groundwater) shortages. I know a bit about the situation in China and India but the problems faced by California and the Middle East are also huge. The situation is grim and could lead to military conflicts. Food security is a major implied difficulty but simple issues of access to safe drinking water are already issues – one global citizen in 7 already has no access to safe supplies.
Generally if you are interested in environmental issues The Guardian is a good read.