Is it hard to believe that in burning carbon based fuels that we can determine the contents of the exhaust and quantify said components? Is it difficult then to understand how those components affect the atmosphere?
Yes
The Earth’s weather system is an extremely complex and interconnected model.
Any model will have to make assumptions of one criteria being variable while hundreds of other variables are held to be constant and then add to that the factor of time in units of decades.
However, we humans, in our insignificant efforts, can take steps to change weather.
Maybe drop a hydrogen bomb in a hurricane.
The biggest component of greenhouse gases is water vapor but we can possibly change that if we all leave our frigs open.