Drawdown (hydrology)
In water-related science and engineering there are two similar but distinct definitions in use for drawdown.
In either case, drawdown is the change in head or water level relative to background condition, indicating the difference in head which has occurred at a given location relative to an initial time at the same location.
A record of hydraulic head through time is more generally called a hydrograph (in both groundwater and surface water).
Aquifer drawdown or overdrafting and the pumping of fossil water may be a contributing factor to sea-level rise.
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