Spatiotemporal Distributions of δD in Atmospheric Water Vapor Based on TES Data During 2004-2009

The spatial and temporal distributions of the stable isotopes such as HD16O (or 1H2H16O, or HDO) andH218O in atmospheric water vapor are related to evaporation in source places, vapor condensation duringtransport, and vapor convergence and divergence, and thus provide useful information for investigation andunderstanding of the global water cycle. This paper analyzes spatiotemporal variations of the content of iso-tope HDO (i.e., δD), in atmospheric water vapor, namely, δDv, and the relationship of δDv with atmospherichumidity and temperature at different levels in the troposphere, using the HDO and H2O data retrievedfrom the Tropospheric Emission Spectrometer (TES) at seven pressure levels from 825 to 100 hPa. Theresults indicate that δDv has a clear zonal distribution in the troposphere and a good correspondence withatmospheric precipitable water. The results also show that δDv decreases logarithmically with atmosphericpressure and presents a decreasing trend from the equator to high latitudes and from lands to oceans. Sea-sonal changes of δDv exhibit regional differences. The spatial distribution and seasonal variation of δDvin the low troposphere are consistent with those in the middle troposphere, but opposite situations occurfrom the upper troposphere to the lower stratosphere. The correlation between δDv and temperature has asimilar distribution pattern to the correlation between δDv and precipitable water in the troposphere. Thestable isotope HDO in water vapor (δDv), compared with that in precipitation (δDp), is of some differencesin spatial distribution and seasonal variation, and in its relationship with temperature and humidity, in-dicating that the impacts of stable isotopic fractionation and atmospheric circulation on the two types ofstable isotopes are different.