PT  - JOURNAL ARTICLE
AU  - Frankenberg, Christian
AU  - Yoshimura, Kei
AU  - Warneke, Thorsten
AU  - Aben, Ilse
AU  - Butz, André
AU  - Deutscher, Nicholas
AU  - Griffith, David
AU  - Hase, Frank
AU  - Notholt, Justus
AU  - Schneider, Matthias
AU  - Schrijver, Hans
AU  - Röckmann, Thomas
TI  - Dynamic Processes Governing Lower-Tropospheric HDO/H<sub>2</sub>O Ratios as Observed from Space and Ground
AID  - 10.1126/science.1173791
DP  - 2009 Sep 11
TA  - Science
PG  - 1374--1377
VI  - 325
IP  - 5946
4099  - http://science.sciencemag.org/content/325/5946/1374.short
4100  - http://science.sciencemag.org/content/325/5946/1374.full
SO  - Science2009 Sep 11; 325
AB  - 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¯ and a model study shows that dynamic processes can entirely compensate for temperature effects on the isotopic composition of precipitation.