It is a common enough gag in cartoons and sitcoms and such to show someone trying to cool the world by throwing open the doors of their freezers or fridges, or cranking up the AC and directing the cool air outside. This is obviously not only futile but counter productive.
Fridges and freezers and AC’s work by compressing a gas (freon or ammonia, commonly); as a gas is compressed, it heats up. If you then run the hot compressed gas through a heat exchanger – a mess of copper tubes, often enough – and transfer that heat to, say, the outside air, when the now-cooled gas is allowed to expand again, it cools down, often by rather a lot. You are not, in fact, really cooling off the whole system; in a perfectly efficient setup, the total thermal energy of a closed environment – a fridge in a sealed chamber, say – would not change no matter how cold you made the inside of the icebox, because the outside would just heat up that much more, exactly balancing the equation. And in reality, nothing is perfectly efficient… so you would actually slowly *add* heat to the total system due to friction in the mechanisms and inefficient electric motors and slight resistance in the wiring, etc.
So obviously firing up a bunch of fridges ain’t gonna cool the planet, because their heat exchanges would simply warm up the atmosphere or lakes that they are connected to.
But… what if you went overboard, and made a fantastically powerful heat pump? Handwave some ridiculous machine, a kilometer ona side, that sucks in atmosphere just as fast and the nuclear reactors powering it will allow. The atmospheric gasses are compressed and warmed up. But not compressed a little, and made kinda warm… I mean compressed *a* *lot,* and made ridiculously hot. Hot enough that the heat transfer mechanism is no longer entirely conduction to the outside air. No, the compressed gases are so hot – call it thousands of degrees – that the gas sheds heat rapidly through *radiation.* Direct these hot gases to the top of the machine, up in the thinner air, and surround the rampagingly bright tubing with mirrors that effectively direct the white light and the IR radiation out into space. The compressed air sheds vast amounts of thermal energy not back into the environment, but off-world. The air is then allowed to expand back to normal pressure; if it has shed enough thermal energy, the machine will probably be spraying cryogenic liquid air out into the world.
I have no doubt that this is a monumentally stupid idea on many levels (not least being that inefficiencies could well overwhelm any cooling effect). But does it seem, at least in principle, like it might possibly be a way to manipulate the overall heat budget of the planet?