Читать книгу Climate Change For Dummies - Elizabeth May - Страница 12

When “global warming” became a household phrase, greenhouse gases (GHGs), which trap heat in the Earth’s atmosphere, got a bad reputation. After all, those gases are to blame for heating up the planet. But, as we discuss in Chapter 2, GHGs in reasonable quantities aren’t villains, they’re heroes. They capture the sun’s warmth and keep it around so that life as it’s known is possible on Earth. The problem starts when the atmosphere contains too great an amount of GHGs. (In Chapter 3, we look at how scientists have determined the correlation between carbon dioxide in the atmosphere and temperature.)

Other factors, which we discuss briefly in the following sections, affect the Earth’s climate. Some are short-term — mostly those are seen as variations in weather, like El Niño or El Niña. The ones that matter most, though, are those that have long-term effects on climate. When the overall temperature of the Earth and the oceans rise, that’s not just a change in the weather. And it’s not just a normal variation that might have been observed in the past. That’s a change in the Earth’s climate.