Other ways of looking at 21st Century Challenges:
James Martin: 16 Megaproblems of the 21st Century.
The Oxford Martin School
The Millennium Project: 15 Global Challenges
Julian Cribb: 10 Challenges
21st Century Challenges / Program by RGS/BGI
Skoll Global Threats
Global Challenges Foundation
Bulletin of the Atomic Scientists
World Economic Forum
Note also:
WEF Global Risks 2015
Union of Concerned Scientists