What is global warming?Global warming is the gradual increase in the overall temperature of earth’s atmosphere mainlycaused by greenhouse gases. While many people think of global warming and climate changeas synonyms, scientists use “climate change” when describing the complex shifts now affectingour planet's weather and climate systems.Climate change encompasses not only rising averagetemperatures but also extreme weather events, shifting wildlife populations and habitat, risingseas, and a range of other impacts.Causes of global warming.Well, humans; greenhouse gases to be precise. This process is called the greenhouseeffect.The "greenhouse effect" is the warming that happens when certain gases in theatmosphere trap heat. These gases let in light but keep heat from escaping, like the glass wallsof a greenhouse, hence the name.Sunlight shines onto the Earth's surface, where the energy isabsorbed and then radiates back into the atmosphere as heat. In the atmosphere, greenhousegas molecules trap some of the heat, and the rest escapes into space.The more greenhouse gases concentrate in the atmosphere, the more heat gets locked up inthe molecules. Examples of these gases are carbon monoxide, nitrogen, fluorocarbons andmany others.Human activity isn't the only factor that affects Earth's climate. Volcanic eruptionsand variations in solar radiation from sunspots, solar wind, and the Earth's position relative tothe sun also play a role.Impacts of global warming.Therapid rise in greenhouse gases is a problembecause it’s changing the climate faster thansome living things can adapt to. Also, a new and more unpredictable climate poses unique
