Abstract:
In the present study, an attempt has been made to correlate the isotopic composition of the air moisture
samples collected on daily basis by condensation method over a period of five years (2007-11) with the
meteorological parameters. The trend of stable isotopic composition of air moisture for the past 5 years
indicates a systematic depletion in isotopic average while the maximum depleted value of air moisture
has been found almost same in all the five years which indicates the changing climatological conditions
at Roorkee i.e. increased arrival .of oceanic vapours with time. This is a very important phenomenon and
need to be understood fully. The isotopic composition of air moisture for the monsoons over a period
from 2007 to 2011 shows a systematic depleting trend with an overall depletion by approximately 33‰
for δ18O and 60‰ for δ2H in 5 years. This systematic trend of change in stable isotopic composition
indicates towards the change in climatological conditions at Roorkee in recent years which is also seen
in other meteorological data. Further, investigations are in progress in this aspect which can contribute to
improve the understanding of the isotope-hydrometeorology of India as well as to consider the stable
isotopic signatures of air moisture and precipitation as one of the important meteorological parameters
because other meteorological parameters only show the change in weather conditions while isotopic
signatures also indicate the cause and source.
