global warming, enhanced greenhouse effect

The terms used to describe additional greenhouse gases in the atmosphere that lead to rapid and sustained additional warming of the average temperature of the Earth’s surface. The naturally occurring greenhouse effect (trapping and radiating enough heat to make living on Earth conducive to species like humans) has now measurably intensified and is making the Earth warmer.

Whilst greenhouse gases occur naturally in the atmosphere, the increased emissions levels measured in recent decades are directly related to human activities such as the burning of fossil fuels and the deforestation of tropical forests. Three main human-made greenhouse gases – carbon dioxide, methane, and nitrous oxide – have rapidly increased as demonstrated from the data sets for these gases over the last 420,000 years.

These increased concentrations of greenhouse gases in the atmosphere within such a short period has led to the trapping of more heat, as well as reducing capacity in the Earth’s natural carbon sinks (forests, oceans, soils) to absorb additional greenhouse gases from the atmosphere or deflect heat (glaciers) back away from the Earth. This therefore exerts a warming influence on the lower atmosphere, which is a primary regulator of climate.

Whilst global warming is the result of increased carbon emissions in the atmosphere that reduce the capacity of the Earth to radiate heat back to outer space, climate change refers to medium-long term changes in our climate patterns that result from global warming.