Hello,
Welcome to healthcare magic.
I understand that you are concerned about your skin tone.
From your history, I would consider delayed
tanning as a cause of your pigmentation. Tanning occurs due to prolonged sun exposure especially in Indian skin. Hot air is not responsible for tanning and it is due to the UV rays exposure. Even if you travel with a cool AC on, the UV rays which penetrate through the car's window can cause tanning.
You could use the following suggestions-
1. Use a broad spectrum sunscreen every 4 hours. Apply even in cloudy weather and even inside the car.
2. Use a facewash containing
glycolic acid as this will exfoliate the skin.
3. at bedtime, use a cream containing
kojic acid,
liquorice, arbutin and tetrahydrocoumarin as a lightening agent to lighten the skin tone.
4. You could get a few sessions of glycolic acid/ retinol based peels done by a
dermatologist.
Hope this helps you.
Take care.