All organisms naturally release carbon dioxide as a product of respiration. Why was global climate change not an issue in the past as it is today ?

Because of humans

Explanation:

We have polluted the Earth so much. There are tons of plastic in the ocean and ice caps are melting faster and faster. Smoke from factories and vehicles are destroying the ozone layer making it even hotter.

that would be called plucking : )

explanation:

''plucking, also referred to as quarrying, is a glacial phenomenon that is responsible for the erosion and transportation of individual pieces of bedrock, especially large "joint blocks". as a glacier moves down a valley, friction causes the basal ice of the glacier to melt and infiltrate joints (cracks) in the bedrock."