I think that it probably is the case that climate change could be related to natural fluctuations in the Earth's climate, but we cannot be certain.

Without conclusive evidence either way, we have to assume that our pollutants are having an effect and take steps to reduce such pollutants as soon as possible.

If we are wrong and it is a naturally occuring change, then reducing pollutants will probably have little effect in preventing it, but at least our air will be cleaner hopefully leading to a reduction in related diseases and a better quality of life for all.