In thinking about global warming, we often forget that greenhouse gases are not inherently bad. Without them, we would have a snowball Earth. But, with too much of them, we risk a fireball Earth. Before mankind started terra forming Earth in spectacular ways and burning fossil fuels as an energy source, the biosphere was able to keep a proper balance of CO2 and oxygen. But, this is no longer possible because of the huge amounts of sequestered carbon dioxide being unlocked from the use of coal, petroleum and natural gas.
What some of us have a hard time understanding is how an invisible gas can act like an atmospheric blanket. To demonstrate, watch below:
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Mythbusters tests global warming theory - does CO2 warm air?
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The Greenhouse Gas Demo
Greenhouse in a Beaker:
After this, the physics is explained in this video:
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How Do Greenhouse Gases Work?