After reading Professor Hanington’s article on Sunspot activity published November 24, 2018, I feel compelled to point out to the scientists claiming that man is solely responsible for global warming that the world has undergone climate change long before humankind has existed.
When speaking of the Ice Age, it has been referred to as the last ice age meaning there has been more than one. Between ice ages there would be global warming. Geologists have found evidence that global warming occurred during the Jurassic Period.
l respectfully suggest that the scientists touting that humans are the only culprits take a look into sciences other than atmospherics to find the causes. I am not saying that humans don‘t contribute to it. I am saying that human activity is not the only cause.
John B. Quirk