Role of the Hudson Bay Lowland as a source of atmospheric methane

Journal Article · Thu Jan 20 04:00:00 EST 1994 · Journal of Geophysical Research

DOI:https://doi.org/10.1029/93JD000261· OSTI ID:81543

Roulet, N T ^[1]; Jano, A ^[2]; Kelly, C A ^[3]; Klinger, L F ^[4]; Moore, T R ^[5]; Protz, R ^[6]; Ritter, J A ^[7]; Rouse, W R ^[8]

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1. York Univ., Ontario (Canada)
2. Ontario Centre for Remote Sensing, Ontario (Canada)
3. Univ. of Manitoba, Winnipeg (Canada)
4. National Center for Atmospheric Research, Boulder, CO (United States)
5. McGill Univ., Quebec (Canada)
6. Guelph Univ., Quebec (Canada)
7. NASA Langley Research Center, Hampton, VA (United States)
8. McMaster Univ., Hamilton (Canada)

Based on point measurements of methane flux from wetlands in the boreal and subarctic regions, northern wetlands are a major source of atmospheric methane. However, measurements have not been carried out in large continuous peatlands such as the Hudson Bay Lowland (HBL) (320,000 km{sup 2}) and the Western Siberian lowland (540,000 km{sup 2}), which together account for over 30% of the wetlands north of 40{degrees}N. To determine the role the Hudson Bay Lowland as a source of atmospheric methane, fluxes were measured by enclosure throughout the 1990 snow-free period in all the major wetland types and also by an aircraft in July. Two detailed survey areas were investigated: one ({approx} 900 km{sup 2}) was in the high subarctic region of the northern lowland and the second area ({approx} 4,800 km{sup 2}) straddled the Low Subarctic and High Boreal regions of the southern lowland. On a per unit area basis, 1.31 {+-} 0.11 and 2.79 {+-} 0.39 g CH{sub 4} m{sup {minus}2} yr{sup {minus}1} were emitted from the southern and northern survey areas, respectively. The extrapolated enclosure estimates for a 3-week period in July were compared to within 10% of the flux derived by airborne eddy correlation measurements made during the same period. The aircraft mean flux of 10 {+-} 9 mg CH{sub 4} m{sup {minus}2} d{sup {minus}1} was not statistically different from the extrapolated mean flux of 20 {+-} 16 mg CH{sub 4} m{sup {minus}2} d{sup {minus}1}. The annual habitat-weighted emission for the entire HBL using six wetland classes is estimated as 0.538 {+-} 0.187 Tg CH{sub 4} yr{sup {minus}1} (range of extreme cases is 0.057 to 2.112 Tg CH{sub 4} yr{sup {minus}1}). This value is much lower than expected, based on previous emission estimates from northern wetlands. 40 refs., 6 figs., 8 tabs.

• OSTI ID: 81543
• Journal Information: Journal of Geophysical Research, Journal Name: Journal of Geophysical Research Journal Issue: D1 Vol. 99; ISSN JGREA2; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
ABUNDANCE
ATMOSPHERIC CHEMISTRY
CARBON SOURCES
EARTH ATMOSPHERE
ECOLOGICAL CONCENTRATION
ECOSYSTEMS
ENVIRONMENTAL TRANSPORT
HUDSON RIVER
METHANE
SIBERIA
WETLANDS