hi,

see if you take admission in bachelors degree in environment science , then you will be awarded bachelors degree in environment science, however in optional subjects if your college has the faculty or management system and option to take for atmospheric science as optional subject then you learn about it. In b.sc in environment science curriculum atmospheric chemistry, Atmospheric circulation,  Meteorology and atmospheric stability like chapters are included.

you may follow the below link and go through the full syllabus:

http://www.du.ac.in/du/uploads/departments/Environmental%20Studies/04042018_Syllabus_Revised_CBCS.pdf