Scale and diversity of the physical technosphere: A geological perspective

We assess the scale and extent of the physical technosphere, defined here as the summed material output of the contemporary human enterprise. It includes active urban, agriculturaland marine components, used to sustain energy and material flowfor current human life, and a growing residue layer, currently only in small part recycled back into the active component. Preliminary estimates suggest a technosphere mass of approximately 30 trillion tonnes (Tt), which helps support a human biomass that, despite recent growth, is ~5 orders of magnitude smaller. The physical technosphere includes a large, rapidly growing diversity of complex objects that are potential trace fossilsor ‘technofossils’. If assessed on palaeontological criteria, technofossil diversity already exceedsknown estimates of biological diversity as measured by richness, far exceedsrecognized fossil diversity, and may exceedtotal biological diversity through Earth’s history. The rapid transformation of much of Earth’s surface mass into th...