True. Well, and then there's the sun. That probably has something to do with it.
Maybe :)
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Funny how the global warming alarmists seem to forget that big fusion reactor up in the sky. And the sun, for reasons as yet unknown, does go thru cycles where its output diminishes. With a long enough spell, you get an ice age on Earth. In fact, we're still recovering from the last ice age.
You think? Is that why planets closer to the sun are warmer than those farther away?
And volcanic activity. And heat island effects in big cities.