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You may have heard of global climate change, which is often called "global
warming."
But how much do regular people understand the science
of climate change?
Take a moment to try to explain to yourself how virtually
all climate scientists think the Earth is warming.
What is the physical or chemical mechanism?
In one study we asked almost 300 adults in the US--
and not a single person could accurately explain the mechanism a global warming
at a pretty basic level.
Allow us to give you a short explanation of how global warming
works: First, here is how
Earth's temperature works without considering how humans influence it:
The Earth absorbs light from the sun,
which is mostly visible light. To release that light-energy,
Earth also emits light. But because the Earth is cooler than the sun,
it emits lower-energy, infrared light. So,
Earth's surface essentially transforms most to the visible light it gets from
the sun
into infrared light.
Greenhouse gases in the atmosphere, such as methane and carbon dioxide,
let visible light passed through, but absorb infrared light--
causing the atmosphere to retain heat.
This energy can be absorbed and emitted by the atmosphere
many times before it eventually returns to outer space.
The added time this energy hangs around has helped keep
Earth warm enough to support life as we know it. Without this greenhouse effect--
caused by these greenhouse gases in the atmosphere--
the Earth's average surface temperature would be about 50 degrees Fahrenheit
cooler,
which is well below the freezing point for ice!
So, how have humans change things?
Since the dawn of the industrial age, around the year 1750,
atmospheric carbon dioxide has increased by 40%--
and methane has almost tripled. These increases cause
extra infrared light absorption, meaning an
extra greenhouse effect, which has caused
Earth to heat above its typical temperature range.
In other words, energy that gets to Earth hasn't even harder time leaving it,
causing Earth's average temperature to increase--thus producing
global climate change.
Please share this video with others so you can help them understand how global
warming works, too.