Simple bacteria thrived on sunlight and CO 2. By-product is oxygen O 2. The volcanoes released. Current Earth: Plants and animals thrive in balance. Plants take in carbon dioxide CO 2 and give off oxygen O 2. That trend of rising temperatures with altitude means that air in the stratosphere lacks the turbulence and updrafts of the troposphere beneath.
Commercial passenger jets fly in the lower stratosphere, partly because this less-turbulent layer provides a smoother ride. The jet stream flows near the border between the troposphere and the stratosphere. Above the stratosphere is the mesosphere. It extends upward to a height of about 85 km 53 miles above our planet. Most meteors burn up in the mesosphere. Unlike the stratosphere, temperatures once again grow colder as you rise up through the mesosphere.
The layer of very rare air above the mesosphere is called the thermosphere. High-energy X-rays and UV radiation from the Sun are absorbed in the thermosphere, raising its temperature to hundreds or at times thousands of degrees.
However, the air in this layer is so thin that it would feel freezing cold to us! Way up. After that, the atmosphere blends into space. Trace amounts of carbon dioxide, methane, water vapor, and neon are some of the other gases that make up the remaining 0. The atmosphere is divided into five different layers, based on temperature. The troposphere is thickest at the equator, and much thinner at the North and South Poles. The majority of the mass of the entire atmosphere is contained in the troposphere—between approximately 75 and 80 percent.
Temperatures in the troposphere decrease with altitude. It reaches from the top of the troposphere, which is called the tropopause, to an altitude of approximately 50 kilometers 30 miles.
Temperatures in the stratosphere increase with altitude. A high concentration of ozone, a molecule composed of three atoms of oxygen, makes up the ozone layer of the stratosphere. This ozone absorbs some of the incoming solar radiation, shielding life on Earth from potentially harmful ultraviolet UV light, and is responsible for the temperature increase in altitude.
The top of the stratosphere is called the stratopause. Temperatures decrease in the mesosphere with altitude. The thermosphere is located above the mesopause and reaches out to around kilometers miles.
Earth is able to support a wide variety of living beings because of its diverse regional climates, which range from extreme cold at the poles to tropical heat at the Equator.
Regional climate is defined by the University Corporation for Atmospheric Research as the average weather in a place over more than 30 years. A region's climate is often described, for example, as sunny, windy, dry, or humid. These can also describe the weather in a certain place, but while the weather can change in just a few hours, climate changes over a longer span of time.
Earth's global climate is an average of regional climates. The global climate has cooled and warmed throughout history. Today, we are seeing unusually rapid warming. The scientific consensus, as stated by the Intergovernmental Panel on Climate Change , is that greenhouse gases, which are increasing because of human activities, are trapping heat in the atmosphere.
To better understand the formation and composition of Earth, scientists sometimes compare our planet with Venus and Mars. All three of these planets are rocky in nature and are part of the inner solar system, meaning that they are in between the sun and the asteroid belt. Venus has an almost fully carbon dioxide atmosphere , with traces of nitrogen and sulfuric acid. The planet, however, also has a runaway greenhouse effect on its surface. Spacecraft have to be heavily reinforced to survive the crushing pressure 90 times heavier than Earth , and the oven-like temperatures Fahrenheit or Celsius , found at its surface.
The clouds are also so thick that the surface is invisible in visible light. Because not much sun reaches the surface, this means that Venus has no significant seasonal temperature changes. Mars also has a mostly carbon dioxide atmosphere , with traces of nitrogen, argon, oxygen, carbon monoxide and some other gases.
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