Climate myths: Any cooling disproves global warming
Let’s start with a thought experiment. Suppose you managed to find some children who knew nothing about the oceans, handed them a long measuring stick and sent them off to the seaside find out whether sea level is rising or falling.
As soon they saw the waves crashing on the shore, the children would realise they had been set a tricky task: how do you measure sea level when it is constantly changing?
If they were smart, the kids would try to find a quiet cove or harbour where there were no waves and start measuring. After an hour or so they would come running up to you. “The sea is going down! The sea is going down!” they’d shout in excitement.
“Not so fast,” you’d reply. “Keep going.” After a day or two, the children would realise the sea rises and falls at least once a day. If they were really dedicated and kept going for several days, they’d soon come running back to you.
“The high water mark is getting lower,” they’d declare triumphantly. “That means sea level is falling.” And once again you’d have to tell them to keep at it.
The moral of this story is that it is very difficult to detect underlying trends that are small compared with short-term changes.