Dynamic Processes Governing Lower-Tropospheric HDO/H2O Ratios as Observed from Space and Ground

Christian Frankenberg, Kei Yoshimura, Thorsten Warneke, Ilse Aben, Andre Butz, Nicholas Deutscher, David Griffith, Frank Hase, Justus Notholt, Matthias Schneider, Hans Schrijver, Thomas Rockmann

Research output: Contribution to JournalArticleAcademicpeer-review

Abstract

The hydrological cycle and its response to environmental variability such as temperature changes is of prime importance for climate reconstruction and prediction. We retrieved deuterated water/water (HDO/H2O) abundances using spaceborne absorption spectroscopy, providing an almost global perspective on the near-surface distribution of water vapor isotopologs. We observed an unexpectedly high HDO/H2O seasonality in the inner Sahel region, pointing to a strong isotopic depletion in the subsiding branch of the Hadley circulation and its misrepresentation in general circulation models. An extension of the analysis at high latitudes using ground-based observations of
δD ¯ ¯ ¯ ¯
δD¯
and a model study shows that dynamic processes can entirely compensate for temperature effects on the isotopic composition of precipitation.
Original languageEnglish
Pages (from-to)1374-1377
JournalScience
Volume325
Issue number5946
DOIs
Publication statusPublished - 11 Sep 2009

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