No one is denying that the climate is changing; just about how much of it is caused by us.
The most vocal say it is caused wholly by us, whereas the climate sceptics say that it is a naturally occurring event over 1000s of years, and we have just accelerated it.
Isn't that saying if it wasn't for us we wouldn't be experiencing it now? If we are accelerating it us then yes it is being caused by us.