While it is true that there have been
cyclical patterns of temperature changes throughout our planet’s history, this does not mean that causes are unknown, unknowable, or all the same.[
citation needed ] The application of the
scientific method is great for working out cause/effect relationships. Scientists have managed to link several warming and cooling cycles in the
geologic history to specific causes.
[55] They have also shown that the modern warming is due to the added output of humans burning fossil fuels and destroying carbon sinks.
[56]In addition, the current climate change is happening
fast — over a period of decades rather than millennia. Past natural climatic patterns that were destructive were associated with cool periods while the projected future catastrophe from AGW is going to be associated with warming; this makes man-made climate change much worse than naturally occurring climate change.
[57]
The existence of previous warming cycles
does not negate the seriousness of the current one. These previous cycles destroyed a great deal of life on the planet, and if similar effects occurred today they would probably destroy all of human civilization, along with the humanity that created it. This does mean that the earth itself will survive, but that no denialist would be around to gloat.
Global warming - RationalWiki