Publication Date:
2012-08-15
Description:
A simple process-based model for the consumption of atmospheric hydrogen (H2) has been developed. The model includes a description of diffusion and biological processes which together control H2 flux into the soil. The model was incorporated into the LPJ-WHyMe Dynamic Global Vegetation Model, and used to simulate H2 fluxes over the 1988–2006 period. The model results have been confronted with field and laboratory measurements. The model reproduces observed seasonal cycles of H2 uptake at different sites and shows a realistic sensitivity to changes in soil temperature and soil water content in comparisons with field and laboratory measurements. A recent study, based on 3D atmospheric model inversion, found an increase of the global H2 sink from soils, with a trend of −0.77 Tg a−2 for the 1992–2004 period (fluxes are negative as soils act as a sink for atmospheric H2). For the same period, however, our process-based model calculates a trend of only −0.04 Tg a−2. Even when forced with drastic changes in soil water content, soil temperature and snow cover depth, our model is unable to reproduce the trend found in the inversion-based study, questioning the realism of such a large trend.
Print ISSN:
0886-6236
Electronic ISSN:
1944-9224
Topics:
Biology
,
Chemistry and Pharmacology
,
Geography
,
Geosciences
,
Physics
Permalink
