When that shortwave energy hits the Earth it heats the Earth. The Earth then emits heats or infrared energy which is what we refer to as long wave radiation. The heat does not pass through greenhouse gases as the gases are not transparent to radiation of that wavelength.
Much the same way that the windows of a greenhouse trap the heat inside the house. So the greenhouse gases keep the Earth warm by preventing the heat from the ground from escaping. Greenhouse gases keep the Earth warm by preventing heat from escaping, they do nothing to actually warm the Earth. The greenhouse effect is when sunlight enters the atmosphere, hits the Earth and is changed to heat and then that heat is radiated is back to space.
Certain gases in the atmosphere block that heat from escaping. Then it is all remitted back to earth in all direction therefore forcing climate change. Electromagnetic radiation travels in waves, and the distance from one wave crest to the next is known as the wave length. Generally speaking when these wave encounter something they will either through it or be blocked by it. A general rule of thumb is the smaller the wavelength the more likely it will pass through the material.
In the illustration above you can see the smaller wavelengths are things like x rays and gamma rays. If you have had to have an x-ray you know that x-rays travel freely through a lot of material such as your skin. However, part of a greenhouse's warmth results from the physical barrier of the glass, which prevents the warmer air from flowing outward. So despite the fact that the atmospheric greenhouse effect has some processes in common with an actual greenhouse, the overall mechanisms driving the greenhouse effect are different and more complex.
You have already learned that Earth's atmosphere is composed primarily of nitrogen and oxygen. These gases are transparent to incoming solar radiation. They are also transparent to outgoing infrared radiation, which means that they do not absorb or emit solar or infrared radiation.
However, there are other gases in Earth's atmosphere that do absorb infrared radiation. These gases are known as greenhouse gases. Below are the most important greenhouse gases that influence Earth's climate system. Water vapor H2O is the strongest greenhouse gas, and the concentration of this gas is largely controlled by the temperature of the atmosphere.
As air becomes warmer, it can hold more moisture or water vapor. When the air becomes saturated or holds as much moisture as the air can at that temperature , the excess moisture will condense into cloud droplets.
And if these droplets are large enough, they will fall as precipitation. Carbon dioxide CO2 is also an important greenhouse gas.
It has a long lifetime in Earth's atmosphere. This makes carbon dioxide a good absorber of wavelengths falling in the infrared radiation region of the spectrum. Carbon dioxide constantly moves into and out of the atmosphere through four major processes: photosynthesis, respiration, organic decomposition or decay, and combustion or the burning of organic material. When trees or plants are cut down, they no longer absorb carbon dioxide, and when they are burned or decompose, they release carbon dioxide back into the atmosphere.
In the United States, land-use activities currently represent a net carbon sink , absorbing more carbon dioxide from the air than they emit. Industry About one-fifth of global human-driven emissions come from the industrial sector, which includes the manufacturing of goods and raw materials like cement and steel , food processing, and construction.
In , industry accounted for In the United States, with Americans buying larger cars and taking more flights and with low gas prices encouraging drivers to use their cars more, transportation is the largest contributor of greenhouse gases. It accounted for Carbon dioxide is the primary gas emitted, though fuel combustion also releases small amounts of methane and nitrous oxide, and vehicle air conditioning and refrigerated transport release fluorinated gases too.
Nationwide, cars and trucks are responsible for more than 80 percent of transportation-related carbon emissions. Buildings Operating buildings around the world generates 6. In the United States, homes and businesses accounted for about 11 percent of warming emissions. These emissions, made up mostly of carbon dioxide and methane, stem primarily from burning natural gas and oil for heating and cooking, though other sources include managing waste and wastewater and leaking refrigerants from air-conditioning and refrigeration systems.
Other Sources This category includes emissions from energy-related activities other than fossil fuel combustion, such as the extraction, refining, processing, and transportation of oil, gas, and coal. Globally, this sector accounts for 9. Since the start of the Industrial Revolution, more than 2, billion tons of carbon dioxide have been released into the atmosphere by human activities, according to the Global Carbon Project. North America and Europe are responsible for approximately half of that total, while the emerging economies of China and India have contributed another 14 percent.
For the remainder, plus countries share responsibility. An analysis of carbon dioxide emissions by country today shows that China now leads the pack, responsible for 27 percent of all emissions. Together, these global powers account for almost 60 percent of all emissions. According to the IPCC, to was likely the warmest year period of the last 1, years in the Northern Hemisphere, where assessment is possible. And all five of the years from to were the hottest on record globally.
It is:. These changes pose threats not only to plants and wildlife, but directly to people. Warmer temperatures mean insects that spread diseases like dengue fever and Zika can thrive—and heat waves are getting hotter and more lethal to humans. People could go hungry when our food supply is diminished thanks to droughts and floods —a National Research Council study found that for every degree Celsius that the planet heats up, crop yields will go down 5 to 15 percent.
Food insecurity can lead to mass human migration and political instability. And in January , the Department of Defense released a report that described the threats to U. In other words, humans are the problem.
The atoms are held together loosely enough that they vibrate when they absorb heat. Eventually, the vibrating molecules release the radiation, which will likely be absorbed by another greenhouse gas molecule.
Most of the gas in the atmosphere is nitrogen and oxygen, which cannot absorb heat and contribute to the greenhouse effect. Some heat is absorbed by greenhouse gases like carbon dioxide and then radiated to space A. Some heat makes its way to space directly B. Right With more carbon dioxide in the atmosphere later this Century, more heat will be stopped by greenhouse gases, warming the planet. Sometime during this century, the amount of the greenhouse gas carbon dioxide in the atmosphere is expected to double.
Other greenhouse gases like methane and nitrous oxide are increasing as well. The quantity of greenhouse gases is increasing as fossil fuels are burned, releasing the gases and other air pollutants into the atmosphere.
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