As I understand it, my location (Tamworthish) is not your "standard" Mediterranean climate, but the olives do well provided that you can keep the water up to them during the year - with an emphasis on the winter season as that's when the buds decide whether to make growth or babies (and babies are the fruit).
We have had 20+ years of acceptable results here, the past few years were exceptional, with near as dammit zero harvest for 2019 and 2020.
My understanding of it is that the traditional Mediteranian climate will gradually move Southwards, meaning that Tasmania and places in Southern Victoria might become closer to the traditional med climate ideals. As I'm definitely NOT a meteorologist, I'd take that all with a grain (or several) of salt!
My feeling is that the groves in Northern Qld, and even into the central regions of Qld, will struggle as global climate change affects the rainfall and temperature profiles.
