I question how much human activity is actually having an impact’
Its important to Question...
There's no doubt in my mind that things are getting warmer! The problem I have with it is the belief that it's the CO2 that's causing the warming. Obviously it's making a contribution, but the actual change, the increase in CO2 is minuscule.
Why is this Important?
Burning fossil fuels not only adds CO2 to the atmosphere, but also adds heat. Open the bonnet of your car and feel the heat emanating from the engine compartment. Your house, Billions of homes heated all over the world, making a significant contribution to the background heat. It is a known fact that the weather, the microclimate, around cities is affected by this heat.
Collecting solar energy converts the heat into electricity. Nuclear power adds energy to the system, whereas solar not only reduces the CO2 problem, but also counteracts the heat problem by removing heat from the atmosphere and converting it into electricity. Therefor, it's important to understand the part that CO2 plays in global warming.
There are many other factors to consider. There's the soot produced by combustion, by car exhausts, a known carcinogen and detriment to people's health. No one mentions that this black Sooty product is ideal for absorbing heat from solar radiation!
That's my issue with the blanket statement that climate change is caused by CO2. It's too simplistic and could/will lead to inefficient methods of mitigating the problem.