ESS11
Prof.
Jin-Yi Yu
Increase of Methane Concentration
qThe atmospheric concentration of methane
(CH4) has increased by
151% (1060 ppb9) since 1750 and continues to increase.
qThe
present CH4 concentration has not been exceeded during the past
420,000 years.
qSlightly
more than
half of current CH4 emissions are anthropogenic (e.g., use of fossil fuels, cattle, rice agriculture
and landfills).