Posts intended to clarify how things work

What factors contribute to increases in planetary temperature?

Physics tells us there are only a few fundamental factors that drive global temperatures. It is helpful to define what I will call the “energy-balancing temperature." This is the average global temperature that the planet’s surface would need to have in order for the rate at which energy leaves the planet by escaping into space to exactly balance the rate at which energy arrives into the planet’s atmosphere, oceans, and land.
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Flow constriction: How the Greenhouse effect warms a planet

Many explanations of the atmospheric Greenhouse effect leave people unclear about how it raises the global temperature. I’d like to look at a simple fundamental principle which sheds light on how warming happens. How do you raise the level of something? If we're talking about water in a reservoir, you might think the answer is pretty simple: to raise the water level, you need to add more water—right? ...
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What would you say to someone who says “The greenhouse effect can’t be real because the Second Law of Thermodynamics says something cooler can’t raise the temperature of something warmer”?

Sometimes people assert that the “greenhouse effect” can’t be true, because they believe the model involves heat flowing from a cool atmosphere to a warmer Earth’s surface, thereby violating the Second Law of Thermodynamics. Various sources of confusion seem to be present...
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