What is "global warming"?

What is "global warming"?

Certain gases that exist naturally in the atmosphere let sunlight through, which warms Earth's surface. But then they trap heat that would otherwise escape into space. That's called the greenhouse effect, and it keeps Earth about 6 degrees Fahrenheit warmer than it would otherwise be. In other words, without the natural greenhouse effect, Earth would be a frozen desert. The greenhouse problem and global warming arise because human beings are causing an increase in the natural levels of those gases, causing a thickening of this natural blanket around Earth, and that inevitably will cause global warming. In fact, global warming is already happening, Earth is already warmer due to this thickening greenhouse blanket – more than a degree warmer than it was a century ago.