TY  - JOUR
A1  - Röckmann, Thomas
A1  - Rhee, Tae Siek
A1  - Engel, Andreas
T1  - Heavy hydrogen in the stratosphere
T2  - Atmospheric chemistry and physics
N2  - We report measurements of the deuterium content of molecular hydrogen (H2) obtained from a suite of air samples that were collected during a stratospheric balloon flight between 12 and 33 km at 40º N in October 2002. Strong deuterium enrichments of up to 400 permil versus Vienna Standard Mean Ocean Water (VSMOW) are observed, while the H2 mixing ratio remains virtually constant. Thus, as hydrogen is processed through the H2 reservoir in the stratosphere, deuterium is accumulated in H2 . Using box model calculations we investigated the effects of H2 sources and sinks on the stratospheric enrichments. Results show that considerable isotope enrichments in the production of H2 from CH4 must take place, i.e., deuterium is transferred preferentially to H2 during the CH4 oxidation sequence. This supports recent conclusions from tropospheric H2 isotope measurements which show that H2 produced photochemically from CH4 and non-methane hydrocarbons must be enriched in deuterium to balance the tropospheric hydrogen isotope budget. In the absence of further data on isotope fractionations in the individual reaction steps of the CH4 oxidation sequence, this effect cannot be investigated further at present. Our measurements imply that molecular hydrogen has to be taken into account when the hydrogen isotope budget in the stratosphere is investigated.
Y1  - 2003
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/1655
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30-37609
SN  - 1680-7324
N1  - © 2003 Author(s). This work is licensed under a Creative Commons License. http://creativecommons.org/licenses/by-nc-sa/2.0/deed.en
VL  - 3
IS  - 6
SP  - 2015
EP  - 2023
PB  - EGU
CY  - Katlenburg-Lindau
ER  -