There is an old gag which asks: "Why don't polar bears eat penguins?" The answer is that polar bears inhabit arctic regions, whereas penguins inhabit antarctic regions, as shown here.

There is a saying that the poles are where weather is made. Weather is a heat-driven system, the temperature difference between the poles and the equator, amongst other things, drives our weather. Air is constantly being either warmed or cooled in a planet-wide system, but air is warmed much more in the equatorial regions and cooled more in the polar regions.  (Please note: this is a deliberate oversimplification for purposes of explanation.)

The climate change skeptic asks - 'Given that the climate changes over millenia due to powerful natural forces, how could humans possibly contribute any significant effect to climate change, given our brief existence in geological time?'

I shall try to answer that question with examples from engineering which show how short-term pulse events can significantly affect long-term cyclic events.

The Influence of Short-Term Events on Long-Term Events.