Jan 9, 2017

Relative contribution of monsoon precipitation and pumping to changes in groundwater storage in India

by
Akarsh Asoka, Tom Gleeson, Yoshihide Wada, Vimal Mishra
,
Nature Geoscience
  • States that the depletion of groundwater resources threatens food and water security in India
  • States that, however, the relative influence of groundwater pumping and climate variability on groundwater availability and storage remains unclear
  • Shows from analyses of satellite and local well data spanning the past decade that long-term changes in monsoon precipitation are driving groundwater storage variability in most parts of India either directly by changing recharge or indirectly by changing abstraction
  • Finds that groundwater storage has declined in northern India at the rate of 2 cm yr−1 and increased by 1 to 2 cm yr−1 in southern India between 2002 and 2013
  • Results show that a large fraction of the total variability in groundwater storage in north-central and southern India can be explained by changes in precipitation
  • Results show that groundwater storage variability in northwestern India can be explained predominantly by variability in abstraction for irrigation, which is in turn influenced by changes in precipitation