Earth’s atmosphere is layered, like an onion. These layers are defined by the temperature changes within them. The boundaries between the layers are notclear-cut-one layer shades into another- and the boundary heights vary with latitude and, in the upper regions, solar activity.
Closet to the earth’s surface is the troposphere, in which the temperatureplummets as you climb higher, dropping to -50º C at about ten kilometers altitude.
The troposphere is about nine kilometers deep at the poles and up to 16 kilometers in the tropics. Clouds, rainhurricanes, hailstorms: almost all weather events take place in this lower layer.
Above the troposphere, the stratosphere extends for a further 40 kilometers.
The ozone layer extends more or lessthroughout the stratosphere, and its absorption of the sun’s ultraviolet energy is responsible for an increase in temperature to about freezing point at an altitude of about freezing point at an altitude ofabout 30 kilometers. Above this height, the temperature drops once more, reaching -100º C in the mesosphere – the third layer, which continues to about 90 kilometers.
The final layer of the atmosphericonion is the thermosphere, in which the temperature once again increases thanks to intercepted radiation from the sun.
Because the atmosphere is so rarefied at such heights, “temperature” becomesless and less meaningful, but it reaches over 50º C. The thermosphere shades gradually into space, and from 80 kilometers upward, most of the oxygen and nitrogen molecules are electrically charged,forming the ionosphere – the useful layer that reflects radio waves, making long-distance broadcasts and communications possible.
Qual é a espessura da atmosfera terrestre?
A atmosfera da Terra é emcamadas, como uma cebola. Estas camadas são definidos pelas mudanças de temperatura dentro deles. As fronteiras entre as camadas não são tons clara-uma camada em outro e as alturas de contorno variar...