Subsection 10.1.4 Greenhouse Effect
The greenhouse effect is a natural process by which certain gases in the Earth’s atmosphere trap and re-emit heat radiated from the Earth’s surface. These gases, including carbon dioxide \((CO_2)\text{,}\) methane \((CH_4)\text{,}\) water vapor \((H_2O)\text{,}\) and nitrous oxide \((N2O)\text{,}\) are known as greenhouse gases. Without the greenhouse effect, the Earth’s average surface temperature would be around \(-18°C (0°F)\text{,}\) which would be too cold to support life. However, human activities, such as burning fossil fuels, deforestation, and agriculture, have increased the concentration of greenhouse gases in the atmosphere, leading to an enhanced greenhouse effect and global warming .
A greenhouse is a man-made structure that is designed to grow plants in a controlled environment. It is typically made of glass or plastic panels that allow sunlight to enter while trapping heat inside, creating a warm and humid environment that is ideal for plant growth.
When sunlight enters the Earth’s atmosphere, some of it is reflected back into space, and some is absorbed by the Earth’s surface. The earth surface then radiates that heat back into the atmosphere. The greenhouse gases in the atmosphere absorb some of this heat energy and re-emit it in all directions, including back to the Earth’s surface. As a result, the greenhouse gases act like a blanket that traps some of the heat energy and prevents it from escaping into space. This causes the Earth’s temperature to be warmer than it would be otherwise, which is necessary for life as we know it to exist on our planet Greenhouse Effect. The energy of light is given by \(E=hf = \frac{hc}{\lambda}\) where \(h=6.67\times 10^{34} Js\) is Planck’s constant, \(c=3\times 10^8 m/s\) is velocity of light, and \(\lambda\) is wavelength of the light. Suppose \(\lambda\) is the wavelength of light of energy \(E\) coming from the sun’s visible light to the earth. When the light eneters into the earth atmosphere and it gets absorbed by the atmospheric gases, plants, and the earth’s surface but when it re-emits and reflects back from the earth surface towards the space it losses some of its energy and becomes less energetic \(E' = \frac{hc}{\lambda'}\) to penetrate our atmosphere except that some amount of light energy is able to penetrate the atmosphere. However, due to increasing population, deforestation, and industrialization the amount of greenhouse gases are increasing making more difficult to the less energetic light rays to leave our atmosphere. Such activities are leading the global warming.
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