PhD defense: Study of the hydrological cycle using satellite-borne isotopologue measurements and model results

/ June 16, 2015/ Atmospheric Physics and Chemistry, IMAU

Samuel Jonson Sutanto, 22 June 2015, 12:45 pm, University Hall, Domplein 29, Utrecht

Promotor: Prof. dr. T. Röckmann

Several phase changes, from evaporation to condensation, during transport of water vapor leave a characteristic imprint on the isotopic composition of water vapor and the corresponding precipitation. This is a main reason that PhD student Samuel Sutanto used the water isotopologues to study some processes in the hydrological cycle.

The thesis shows that the transpiration is the largest contributor to the evaporation fluxes from continental area. Sutanto found that the isotopic composition of water vapor is a better climatic indicator for drought and flood than the Nino-3 index over Indonesia during ENSO. The rain out, less rain re-evaporation of falling droplets, and increase of convective updrafts and diffusive exchange within the convective systems, play an important role in the hydrological cycle. He also stated that regions with intense mixing and strong convection are marked by a flatter isotopic gradient.

PhD student Samuel Sutanto conducted his research based on the measurements of the atmospheric water isotopologue from satellites and model results worldwide.