It is the new snapchat update. The yellow heart means- you're each others #1 best friends. Yes I'd like to know too. I think it means your best friends but not sure!!
Carbon dioxide in the atmosphere: 1  allows sunlight and heat into the atmosphere, but doesn't let it get out, causing the Earth to heat up. 2  along with water vapor, methane, and a few other gases keep the Earth from becoming a deep freeze on the side away from the Sun.arbon dioxide in the atmosphere: 1  allows sunlight and heat into the atmosphere, but doesn't let it get out, causing the Earth to heat up. 2  along with water vapor, methane, and a few other gases keep the Earth from becoming a deep freeze on the side away from the Sun.
Respiration and combustion - burning - both release carbon dioxide into the atmosphere. These processes form a carbon cycle in which the proportion of carbon dioxide in the atmosphere remains about the same.