درس الغلاف الجوي، الفصل الثاني، العلوم المتكاملة PDF

# Chapter Two: The Atmosphere ## Chemical reactions and their impact on water quality ### 2.1 Atmosphere and its components #### Atmosphere - The atmosphere is a complex system of gases that surrounds Earth. Earth's gravity keeps Earth's atmosphere in place. - It plays an important role in regul...

# Chapter Two: The Atmosphere ## Chemical reactions and their impact on water quality ### 2.1 Atmosphere and its components #### Atmosphere - The atmosphere is a complex system of gases that surrounds Earth. Earth's gravity keeps Earth's atmosphere in place. - It plays an important role in regulating the planet's temperature, climate, and weather patterns. - The atmosphere is composed of several layers, each with its own unique characteristics and functions. - Mercury is the smallest planet in our solar system. It's also the closest planet to the sun. - Because Mercury doesn't have a thick atmosphere like Earth, the sun's heat can directly hit its surface. This makes Mercury very hot. - During the day, Mercury can get hotter than an oven! But at night, it can get incredibly cold. This is because there's nothing to trap the heat on Mercury, so it quickly escapes into space. #### Ozone Layer - The ozone layer is found at an altitude of approximately 10 km - 55 km from The Earth's surface. - The ozone is characterized by its ability to absorb short-wave ultraviolet radiation. - The ozone is very toxic. #### Functions of the Atmosphere - **Temperature regulation:** The atmosphere traps heat from the sun through the greenhouse effect, helping to maintain a habitable temperature on Earth. - **Protection from harmful radiation:** The ozone layer absorbs harmful ultraviolet radiation from the sun. - **Weather patterns:** The atmosphere is responsible for weather patterns, such as rain, snow, wind, and storms. - **Life support:** The atmosphere contains the gases necessary for life, including oxygen and carbon dioxide. #### Composition of the Atmosphere - **Nitrogen (N2):** 78% of the volume of the atmosphere (inert gas) does not easily react with other gases and elements. - It needs special conditions such as lighting or very high temperatures to react, so its oxides are very small in the air. - **Oxygen (O2):** 21% of the volume of the atmosphere (chemically active) - Active element in combustion. - Active element in respiration. - Active element in natural industrial chemical reactions. - Active element in industrial chemical reactions. - **Argon (Ar):** 0.93% of the volume of the atmosphere. (inert gas) - **Carbon dioxide (CO2):** 0.04% of the volume of the atmosphere, plants use this gas to make food (photosynthesis). - **Water vapor (H2O):** - Its percentage varies from one place to another in the near layer of the atmosphere. It helps make clouds and rain (weather and climate phenomena). #### Approximate composition of the air | Gas | Percentage | |---|---| | Nitrogen | 78% | | Oxygen | 21% | | Other Gases | 0.9% | NB "Other gases" includes carbon dioxide (0.1%) and small proprieties of other gases include argon and water vapor. #### Layers of the Atmosphere - The atmosphere is composed of several layers, each with its own unique characteristics and functions. - The lowest layer of the atmosphere. - Thickness ranges from 8 km at the poles to 18 km at the equator. - Temperature decreases with altitude reduced by one degree Celsius for every 176 m. - This is due to decreasing atmospheric pressure with altitude, which leads to the expansion of the air, which requires energy from some of the kinetic energy of the air molecules. - Contains most weather phenomena. Cloud formation, rainfall, wind movement, etc. - Above the troposphere, its height up to 50 km above sea level. - Contains the ozone layer. - The temperature does not change through the stratosphere layer until an altitude of 20 km(start of the ozon layer). - Temperature increases with altitude due to ozone absorbing ultraviolet radiation. - Preferred for airplane flights due to horizontal air movement. - The coldest layer of the atmosphere. (-90 °C) - Thickness of about 30 km. - Most meteors burn up here, protecting Earth. - Extends to about 640 km above sea level. - Electrically charged due to ionization of atmospheric atoms by solar radiation. - Used for long-distance radio communications due to its ability to reflect radio waves. #### The effect of atmospheric pressure on wind movement - It is the horizontal difference in air pressure. - Imagine the atmosphere as a giant ocean of air. - Just like water flows from higher elevations to lower elevations, air flows from areas of high pressure to areas of low pressure - This movement of air is what we call wind. #### Weather Maps - Weather maps(Meteorological Map( )خرائط الطقس are graphical representations of meteorological conditions )حالة الطقس across a specific region or the entire globe. They use symbols, colors, and lines to depict various weather elements like temperature, pressure, wind, precipitation, and cloud cover. - Isobars(Lines of Equal Pressure) are lines on a weather map that connect points of equal atmospheric pressure. These lines help visualize areas of high pressure (H) and low pressure (L). #### Mercury barometer - A mercury barometer is used to measure atmospheric pressure - The value of atmospheric pressure at sea level at 0 degrees Celsius is called the standard (normal) atmospheric pressure and is equal to 101300 N/m2, which is equivalent to 1013 millibar, or 760 mm.Hg. - standard (normal) atmospheric pressure= 101300 N/m² = 1013 millibar = 760 mm.Hg - In the figure, a mercury barometer has a vertical height difference between the two mercury levels of 760 mm. - Why is this height representative of atmospheric pressure? - How can the barometer be used to determine the height of a mountain.