This is not a matter of faith. Climatology is not a religion. Historical and present measurement data are unavoidable. The changes are getting faster and most of the people who live now will see a climate disaster. And it will be a weak consolation that people do not cause it.
It has not been proven beyond reasonable doubt that human activities are solely responsible for climatic change, but they have certainly contributed significantly.
As for whether climatic change might be "a cyclic phenomenon occurring over long periods of time", it depends on the time frame and whether reliable data are available for suitable empirical analysis.
In the case of earthquakes, you are wrong. Plate tectonics is the main geological theory about the interior of the Earth. Geological knowledge is not as hermetic as it may seem, so I urge you to reach for one of the many great books written for people like you. You will know for yourself which matters are influenced by humanity and which matters have no influence.