The stable isotope signal of atmospheric water vapour in Sydney, Australia

摘要: The stable isotopic composition of atmospheric water vapour is related to the hydrological processes that occuralong back trajectory an air mass, including evaporation at moisture source, mixing andprecipitation. Incorporation isotopes into weather and climate prediction models therefore has thepotential aid in their evaluation, calibration improvement, but this requires availability continuous timeseries isotope data compare with isotopically-enabled simulations. We present analysis a 15-month highresolution time series measurements site near Sydney, Australia.The deuterium exhibits large amount variability (-60 -180 per mille), reflecting range weatherconditions encountered near-coastal measurement site. Using collocated meteorological surface radonmeasurements, together analysis, we investigate major contribute variabilityin value Sydney region. indicates lowest isotopevalues are generally associated cold fronts passing over When front passes ornear site, can be observed change by up 100 mille within thespace few hours. In addition, frontal passages contrasting source precipitation historiesexhibit systematic differences signals as they pass Sydney. On other hand,higher more slowly changing values anticyclonic conditions. From thisstudy it clear variations strongly influenced historyof parcels synoptic scale.