Modelling CH 4 emissions from arctic wetlands: effects of hydrological parameterization

• Main Authors: Petrescu, A. M. R., van Huissteden, J., Jackowicz-Korczynski, M., Yurova, A., Christensen, T. R., Crill, P. M., Bäckstrand, K., Maximov, T. C.
• Other Authors: Department of Hydrology and Geo-Environmental Sciences Amsterdam, Vrije Universiteit Amsterdam Amsterdam (VU), Skane University Hospital Lund, Stockholm Univ., Department of Geology and Geochemistry, the Russian Academy of Sciences Moscow, Russia (RAS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2008
• Subjects: [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO]; [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph]; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [SDU.STU]Sciences of the Universe [physics]/Earth Sciences; Arctic; Abisko; Indigirka; Stordalen; Torneträsk; Northern Sweden; permafrost; Siberia
• Online Access: https://hal.science/hal-00297667; https://hal.science/hal-00297667/document; https://hal.science/hal-00297667/file/bg-5-111-2008.pdf

International audience This study compares the CH 4 fluxes from two arctic wetland sites of different annual temperatures during 2004 to 2006. The PEATLAND-VU model was used to simulate the emissions. The CH 4 module of PEATLAND-VU is based on the Walter-Heimann model. The first site is located in northeast Siberia, Indigirka lowlands, Kytalyk reserve (70° N, 147° E) in a continuous permafrost region with mean annual temperatures of ?14.3°C. The other site is Stordalen mire in the eastern part of Lake Torneträsk (68° N, 19° E) ten kilometres east of Abisko, northern Sweden. It is located in a discontinuous permafrost region. Stordalen has a sub arctic climate with a mean annual temperature of ?0.7°C. Model input consisted of observed temperature, precipitation and snow cover data. In all cases, modelled CH 4 emissions show a direct correlation between variations in water table and soil temperature variations. The differences in CH 4 emissions between the two sites are caused by different climate, hydrology, soil physical properties, vegetation type and NPP. For Kytalyk the simulated CH 4 fluxes show similar trends during the growing season, having average values for 2004 to 2006 between 1.29?2.09 mg CH 4 m ?2 hr ?1 . At Stordalen the simulated fluxes show a slightly lower average value for the same years (3.52 mg CH 4 m ?2 hr ?1 ) than the observed 4.7 mg CH 4 m ?2 hr ?1 . The effect of the longer growing season at Stordalen is simulated correctly. Our study shows that modelling of arctic CH 4 fluxes is improved by adding a relatively simple hydrological model that simulates the water table position from generic weather data. Our results support the generalization in literature that CH 4 fluxes in northern wetland are regulated more tightly by water table than temperature. Furthermore, parameter uncertainty at site level in wetland CH 4 process models is an important factor in large scale modelling of CH 4 fluxes.