[ophic]

Have they no memory of how the weather was when they younger??

This isn't a reliable method of determining climate change, for the main reason that there are a set of longer weather cycles than annual ones at work. A nice example would be El Nino which follows a 3-5 year cycle, but there are many identifiable cycles on a much longer scale - 100s of years, and probably many more that haven't been identified yet.

Not that I'm trying to dilute your point, which I fully agree with.