Atmospheric carbon dioxide is the primary source of carbon in life on Earth and its concentration in Earth's pre-industrial atmosphere since late in the Precambrian was regulated by photosynthetic organisms and geological phenomena.
At about 55 km, the mesosphere begins. In the mesosphere, the temperature decreases with height again, because there is very little ozone to warm up the air. Finally, the mesopause divides the mesosphere from the thermosphere, which is the section of the atmosphere higher than 90 km. In this region, the temperature increases again. This time, it is molecular oxygen (O2) that causes the temperature increase.
Temperature increases as you gain altitude in the stratosphere and the thermosphere. Temperature decreases as you gain altitude in the troposphere and mesosphere. Air temperature varies in complicated ways with altitude. Near the Earth's surface, air gets cooler the higher you climb. As you climb a mountain, you can expect the air temperature to decrease by 6.5 degrees C for every 1000 meters you gain. This is called the standard (average) lapse rate. If air temperature is 30 degrees C at sea level as shown above, you can expect it to be around 10.5 degrees C at air altitude of 3000 meters because of the lapse rate. Plan an expedition! You are going to climb Mount Audubon in Colorado today!