Twenty-one of the world's 37 largest aquifers are beyond their tipping point, which means that more water was removed than replaced. Many reservoirs have lost their capacity to recharge. The growing pressure on water resources for agriculture, industries (mining industries, oil exploitation, etc.) and human needs is one of the XXIst century's biggest challenge. The level of water is also reducing in rivers and above-ground reservoirs.

The NASA data demonstrate the critical situation in which we are today. North Africa, India, or Pakistan are among the countries where the shortages already represent a danger.

Water shortage is a crucial issue. Economical and political instability may come out of it. Tensions around water access will increase in the next decades.