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| Titel |
Wintertime CO2 efflux along the trans-Alaska pipeline |
| VerfasserIn |
Yongwon Kim, Changsub Shim |
| Konferenz |
EGU General Assembly 2011
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 13 (2011) |
| Datensatznummer |
250048983
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| Zusammenfassung |
| This research was conducted to estimate CO2 efflux through the snowpack along the
trans-Alaska pipeline (ca. 660 km) from 2005 to 2010 during the winter season. The pipeline
is existed along the boreal forest and tundra of Alaska. In-situ Wintertime CO2 efflux was
measured with a dynamic chamber system that consisted of a chamber (22 cm in diameter
and 6 cm high), pump, NDIR (CO2 analyzer), and a laptop computer. Soil temperature and
snow depth were measured with a portable thermocouple and from snow pit-wall. The
difference in wintertime CO2 efflux was remarkably showed in boreal forest and tundra
during last six winter seasons, suggesting the latitudinal CO2 efflux gradient. The efflux was
also presented inter-annual variation, indicating the temperature dependence. This may be
due to the difference of observation period (e.g., January, February, March, and April). Mean
CO2 efflux was 0.43±0.17 gCO2-C/m2/day in soil temperature of -12±4.7 Ë C
during the seasonally snow-covered period, and 0.88±0.51 gCO2-C/m2/day in soil
temperature of -1.8±3.0 Ë C during the snow-thawing period. Before and during the
snow-thawing season of 2010, mean CO2 efflux between both seasons appeared to show
the magnitude of an order. The efflux ranged from 0.021±0.004 gCO2/m2/day
near coastal tundra to 1.7±0.24 gCO2/m2/day in white spruce forest during the
snow-thawing season. A relationship between mean CO2 efflux at each site and mean soil
temperature at 5 cm below the surface along the trans-Alaska pipeline is a good
exponential, which the equation is as follows: CO2 efflux = 885-
exp(0.335-
Ts) (R2=0.86;
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