have humans begun to change the climate?

spatial scale: local, regional, or global

short-wave radiation from the sun warms the earth

little is absorbed by the atmosphere

the heated earth emits longwave radiation

but gases in atmosphere absorb longwave radiation therefore the Earth is warmed.

the warming is a natural feature ~ 20C

but if we add more gases we will cause more warming.

is a natural gas. Normal, cyclical nature of the gas.

El Nino effect strongly influences the

more cloud (negative feedback). More clouds = less solar radiation.

green plants and the biosphere (natural and domesticated)

Earlier snowmelt, lesser amounts of sea ice (aeral extent).

pre-industrial levels of methane: 650 PPB

Some topics in this essay:
Effect Process, Environmental Impacts, El Nino, Global Warming, Impacts Economic, Oxide N2O, Tropical Regions, Chlorofluorocarbons CFCs, Forestry Controls, Methane CH4, fossil fuels, environmental impacts, tropical regions, prevent deforestation plant, deforestation plant, ppb increasing, prevent deforestation, ppb 1990, pre-industrial levels, plant trees, warming warming, burning fossil fuels,