Teeter-totter

People who don't want to believe in global warming/climate disruption, because it's too scary and they don't want to be inconvenienced by changing their habits, will say things like "the weather goes up and down," as if that disproves the evidence of our own experience of rising temperatures.

It's like a teeter totter. When you have people of about the same weight on each end, they can go back and forth pretty evenly. Add someone to one end, it might still be able to go back and forth, as each side pushes off, but the heavier side will spend less time high in the air than the lighter side. To say nothing has changed because it is still going up and down would be silly.