A vast store of freshwater that circulates beneath the land surface is increasingly tapped to serve the water needs of human communities. Groundwater represents the largest component of the active hydrological cycle and its movement through the subsurface affects many aspects of the Earth system. In a new groundwater focus, Nature Geoscience presents a collection of research papers and opinion pieces that discuss the influence of groundwater on hydrological, environmental and geological processes.
» Groundwater on Nature Geoscience
Editorial: Groundwater exposed
Groundwater flow meddles with hydrological, environmental and geological processes. As water scarcity issues mount for people living above ground, the vast stores of freshwater in the subsurface require research attention.
Drought in the Anthropocene
Drought management is inefficient because feedbacks between drought and people are not fully understood. In this human-influenced era, we need to rethink the concept of drought to include the human role in mitigating and enhancing drought.
Groundwater: How much and how old?
A global picture of the age structure and flow path of groundwater is lacking. Tritium concentrations and numerical modelling shed light on both the most recently replenished and the longest stored groundwater within Earth’s continents.
Groundwater: India’s drought below ground
Substantial proportion of global streamflow less than three months old
Streamflow is a mixture of precipitation of various ages. Oxygen isotope data suggests that a third of global river discharge is sourced from rainfall within the past few months, which accounts for less than 0.1% of global groundwater.
Groundwater flow as a cooling agent of the continental lithosphere
Groundwater flow redistributes heat in the Earth's crust. Numerical simulations of groundwater flow show net cooling of groundwater basins, as well as cooling of the underlying lithosphere in areas where groundwater flows over large distances.
The global volume and distribution of modern groundwater
Groundwater recharged less than 50 years ago is vulnerable to contamination and land-use changes. Data and simulations suggest that up to 6% of continental groundwater is modern—forming the largest component of the active hydrological cycle.
Asia’s water balance
Multiple factors determine how much water is and will be available in the river basins of Asia. To expose hotspots and help adaptation, these factors must be assessed together at the basin level.
... and more from the archives.