"Climate change" is the term used to refer to changes in the average weather over time; as short a period as a few decades or as long as thousands of years. The changes may come from Earth processes (volcano eruptions, orbital variations), can be driven by external forces (level of solar activity) and more recently, can result from human activities (deforestation, use of fossil fuels for energy).
Currently, "climate change" usually refers to observed ongoing changes in modern climate, including the increase in average surface temperature, "global warming". Recent studies indicate that the increase in greenhouse gases over the last two hundred years is the primary cause of global warming.
According to scientific research, the warming produced as greenhouse gases trap heat, plays a key role in regulating Earth's temperature. However, with the onset of the Industrial Revolution (1800) and increased consumption of carbon based fossil fuels, the percent of greenhouse gases and especially carbon dioxide in the atmosphere, have risen to their highest level in hundreds of thousands of years.