Today, a growing number of scientists argue that global peak oil may be upon us—an argument that would seem to be supported by the increasingly heroic measures oil companies are taking (such as the ultra-deepwater drilling in the Gulf of Mexico) to keep up with global oil demand.
Many underground aquifers and even some surface water stored in lakes and glaciers can indeed be thought of as non-renewable—and thus subject to peak and decline–because they can be depleted faster than the natural recharge rate.
