What causes an increase in greenhouse gases?
Human activities since the start of the industrial era around 1750 have increased the levels of greenhouse gases in the atmosphere. The 2007 assessment report compiled by the IPCC noted that “changes in atmospheric concentrations of greenhouse gases and aerosols, land cover and solar radiation alter the energy balance of the climate system”, and concluded that “increases in anthropogenic greenhouse gas concentrations is very likely to have caused most of the increases in global average temperatures since the mid-20th century”.
