Information-Modeling Technology for the Environmental Monitoring - New Ecoinformatics Tools in Environmental Science: Applications and Decision-making - page 72

Fig. 1.38 Oxygen fluxes in the BCSS realized as the MGBO unit. Notation is given in Table 1.12

1.6.4 Biogeochemical Cycle of Methane

The SMKP item of the BCSS model includes additional descriptions of the methane
cycle components that are not taken into account in other biogeochemical cycles.
Methane like carbon dioxide belongs to greenhouse gases. The spectrum of its
natural and anthropogenic sources is wide, and its greenhouse effect exceeds 20
times that of CO 2 though its concentration (

1.6 ppm) in the atmosphere is about
200 times less than that of CO 2 (Polischuk and Polischuk 2013). By the greenhouse
effect, it is now second to carbon dioxide. Methane also affects the ozone content in
the stratosphere and plays a key role in transformation of chemically active Cl into
less active HCl. Before the human interference, the natural cycle of methane had
been balanced with respect to climate. With extracting natural combustible gases
consisting by 90

*

95 % of methane, humankind has contributed to this cycle factors
of instability and uncertainty. In the whole, during the last 200 years the anthro-
pogenic contribution to the input of CH 4 to the atmosphere has doubled. A situation
has occurred when the difference between methane concentrations at Poles reaches
150 ppb. Most of the authors estimated the level of the global emission of methane
into the atmosphere at 535

-

10 6 tCH 4 year − 1 , of which 375 10 6 tCH 4 year − 1 is × ×

10 6 tCH 4 year − 1 being from the rice of anthropogenic origin (50 × fields).