It's not "the Earth is huge". Time is "huge". We're in an essentially dormant era of volcanic activity. All the volcanic activity since humans have been around is the butterfly flapping its wings. Real volcanic activity is the examples in my first two links, which are the hurricane.
Over the last half century, humans input more carbon than volcanic activity (not counting other volcanic outputs). At least that we know of. As my third link indicated, we may only be discovering the tip of the iceberg of current volcanic output as we begin to understand it better.
In the end, it goes back to anthropogenic activity being nothing more than statistical noise over half a billion years. If you want to worry about "global warming" flooding Los Angeles, that's fine, but that's a human problem. That doesn't affect the Earth at all, only puny humans. When you consider that 99% of all species that ever lived on Earth are extinct, maybe it will help put it in perspective. Humans would need to be around for millions of years to equal catastrophic volcanic output, which happened over millions to hundreds of millions of years.
As for "climate scientists". If you're using them to prove a point, it's "some climate scientists", since other climate scientists, especially planetary climatologists and physicists, would argue a different thesis. Ref: Freeman Dyson, who knows closed systems better than anyone else on the planet.