The law and its premise is nuts, lets just get that out of the way first.
"The intentional injection, release, or dispersion, by any means, of chemicals, chemical compounds, substances, or apparatus within the borders of this state into the atmosphere with the express purpose of affecting temperature, weather, or the intensity of the sunlight is prohibited," the bill reads.
So on one hand this is a reading about banning any efforts of geoengineering. But modern day airplanes already dump "chemical compounds" into Tennessee airspace today as part of jet engine exhaust. The argument would be "oh, planes are okay because they're not dumping to affect weather even though those gases are affecting the weather via climate change." Doesn't that argument open up license for anyone to dump whatever they want (including geoengineering materials) if they can claim that isn't their primary purpose?
I mean, planes already inject, release, or disperse a lot of chemicals, chemical compounds, substances into the atmosphere, namely CO2 and water, which is why there are contrails.
Reading comprehension: with the express purpose of… That’s not the express purpose of those planes.
Critical thinking: the express purpose is whatever the creator/operator of the machine says it is.
Jet engines on a plane's express purpose is to create a high pressure jet of air out one side to propel the craft forward. However, jet engines express purpose can also used to put out oil well fires:
What makes one vs the other? Whatever the creator and operator of the machine decides.
Specifically about geoengineering,
There is a company releasing sulfur in geoengineering experiments source.
Spraying sulfur is also used in gardening to treat plant disease and pest control. source
So if I say my "express purpose" of releasing sulfur is for plant disease and pest control, even though the other thing it could do would be geoengineering via the same release, I would be in compliance with the wording of the law yet still be geoengineering.