Abstract:
Isotope hydrology is a field of hydrology that uses isotopic dating to estimate the age and origins of water and its movement
within the hydrologic cycle. Water molecules carry unique fingerprints, based in part on differing proportions of the oxygen and
hydrogen isotopes that constitute all water. Isotopes are forms of the same element that have variable numbers of neutrons in
their nuclei. This article presents the details of hydrological studies using isotope techniques undertaken by National Institute of
Hydrology, Roorkee (India) during the last few years.