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.
The first 20 parts per million of carbon dioxide in the atmosphere provides 1.6Â°C of warming, after which the effect drops away rapidly. From the current level of 400 parts per million, each addition of 100 parts per million adds only 0.1Â°C of warming.