A person who studies the atmosphere , weather and weather forecasting is known as -

meteorologist - A person who studies the atmosphere , weather and weather forecasting

sonologist - A person who studies the properties or perception of sound. in Medicine, an expert or specialist in the performance and interpretation of medical examinations by ultrasonography.

radiologist - Radiologists are medical doctors that specialize in diagnosing and treating injuries and diseases using medical imaging (radiology) procedures

hydrologist - is a scientist who researches the distribution, circulation, and physical properties of the earth's underground and surface waters.