Question

Hypothesis of global warming

Answer 1

Global warming is caused by the erosion of the ozone layer and excess carbon dioxide from human activity.

Answer 2

Global warming is driven by an imbalance between how much energy the planet takes in from the sun, and how much it lets back out into space in the form of thermal radiation. The planetary energy balance has been off kilter ever since humans started burning massive amounts of fossil fuels, such as coal and oil, for energy and transportation. (Natural factors have altered the energy balance in the past, causing ice ages, for example.)

Today, it’s widely agreed that the planet is warming because we’re taking in more energy than we’re letting out, thanks to growing concentrations of greenhouse gases such as carbon dioxide, which help keep outgoing energy from escaping into space.