A scientist who studies lightning is called an atmospheric physicist or a lightning researcher. They study the properties, mechanisms, and effects of lightning to better understand its behavior and minimize its risks to people and infrastructure.
That would probably fall under climatologist.
A scientist who studies radioactivity is called a nuclear physicist or a radiologist.
Someone who studies waves is called a wave scientist or a wave physicist. They specialize in the interaction, behavior, and properties of different types of waves, such as sound waves, light waves, and ocean waves.
A physicist studies motion. This field of study includes understanding the properties of objects in motion, analyzing the causes of motion, and predicting the behavior of objects based on their motion.
A scientist who studies physics is called a physicist. Physicists explore the fundamental principles governing the behavior of matter and energy in the universe through theoretical and experimental methods.
A biotechnology scientist.
An Oceanographer. Marine Biologist, that sort of thing.
A scientist that studies viruses is called a virologist.
A scientist who studies mollusks is called a teuthologist.
A scientist that studies bears would be called an ursinologist.
virologist
An aviologist.
Bridgeologist
astronomer
A meteorologist.
biologist
A vulcanologist