The problem with climate change is precisely this.
In order to convince everyone we need evidence. However evidence, strictly and scientifically speaking, can only be produced once a phenomenon is fully observed, understood, and reproducible.
In the case of climate change that means waiting for the changes to fully happen, which would be too late if climate change is indeed real.
So you are left with a choice: trust the partial data we have and conclude that climate change is happening, or deny it and hope it never materializes. The third option would be to consciously prefer to wait for climate change to fully materialize and only then take action, but this to me sounds a bit suicidal.
It's happening, present tense. The data is in, you can see it with your own eyes. It's clear as day (pun intended).
There is a long term correlation with solar activity(CME's,Sunspots,Solar flares) that can attest for large climatic swings of the past.
The science is not clear as day, and if you stopped searching for the truth of the matter you've stopped do science.
Based on 2020's level of solar activity, would you expect it to be hotter or colder than it actually is?
Because from what I've seen, you'd expect it to be colder.
Which means something else is causing the temperature rise.
So why bring up solar activity at all?
Climate Change: How Do We Know? https://climate.nasa.gov/evidence/
Large swings of the past aren't as quick as you think they are, or as we are experiencing today: