We're facing serious resource constraints in a number of key areas, what's the most critical of these and what's the biggest factor in creating that scarcity?
Janet Larsen from the Earth Policy Institute, says: ""With our human population expanding and resource consumption growing even faster, we are close to hitting the wall in a number of arenas—fresh water, oil reserves, minerals like phosphorous for fertilizer, oceanic fisheries, and nature’s ability to absorb climate-altering carbon dioxide, among others. But the scarcest resource of all is time.
We do not know exactly how much time we have before the problems created by our excesses are too big or too far along for us to handle, but we do know that time is running out."
Read more: What's the Greatest Resource Scarcity We Now Face?"