Tmv destroys chloroplast in a leaf explain how this could affect the growth of the plant

Chloroplasts in the plants can accumulate high levels of toxic singlet oxygen, a reactive oxygen species formed during photosynthesis. Destroyed chloroplast makes the plant wither up and probably die because the plant's chloroplasts are the considered as the nutrient makers. The Chloroplast turns light into energy and without energy it will not be converted to sugar. Since they are the only thing in nature that is able to covert energy to sugar, it would greatly affect the process and affects growth of the plant which are food and oxygen producer so probably human would also run out of food and Oxygen.

Well, both latitude and intensity of light affect temperature because, the higher the light intensity, the higher the temperature and since latitude is the measure of how close you are to the equator, then the closer to the equator you are, the higher the temperature is.