تصنيف:تغير مناخي

Climate change refers to the variation in the Earth's green house or regional climates over time. It describes changes in the variability or average state of the atmosphere - or average weather - over time scales ranging from decades to millions of years. In recent usage, especially in the context of environmental policy, the term "climate change" is often used to refer only to the ongoing changes in modern climate, including the average rise in surface temperature known as global warming.