Climate…
It has warmed since the end of the Little Ice Age, thank goodness.
This warming will have been caused in part naturally and in part by man.
How much has it warmed and what is man’s contribution isn’t known with any degree of accuracy.
Burning hydrocarbons generates CO2 and this causes warming. That’s what the physics shows.
All agree that doubling CO2 causes a temperature increase of ~1C.
But here is the disagreement…
some climate scientists hypothesise that there is an additional climate sensitivity factor caused by the extra CO2.
This sensitivity factor isn’t agreed upon and hasn’t been observed.
Is warming harmful?
Some will argue that it is, others argue that civilisation and life thrives in the warmth. Certainly, the planet is unusually cold today, compared to the average across the Phanerozoic.
The Nobel Prize winning climate economist, William Nordhaus, forecasts that the world will be some 430% more wealthy by 2100 despite climate change impacts - civilisation is thriving.
So, we have a poor understanding of climate with little data. And this field of study has been dreadfully distorted by money and politics, making it difficult to get to the facts.
Consequently, I think it profoundly wrong to upend our industrial civilisation in pursuit of net zero.