Week 2 Composition Of The Atmosphere Geo 114 PDF
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This document explores the composition and structure of the Earth's atmosphere, describing its layers and the variables influencing pressure and temperature. It covers important concepts such as the various gases and temperature patterns within the atmosphere.
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COMPOSITION OF THE ATMOSPHERE SIZE OF THE EARTH’S ATMOSPHERE Fifty percent of atmospheric mass is within 3.8 miles (6 km) of Earth’s surface More than 98% of atmospheric mass lies within 26 miles (26 km) of sea level Mt. Denali, North America’s highest p...
COMPOSITION OF THE ATMOSPHERE SIZE OF THE EARTH’S ATMOSPHERE Fifty percent of atmospheric mass is within 3.8 miles (6 km) of Earth’s surface More than 98% of atmospheric mass lies within 26 miles (26 km) of sea level Mt. Denali, North America’s highest peak – 20,320 feet (6.19 km) COMPOSITION OF THE ATMOSPHERE Permanent & Variable Gases The three principal gases: nitrogen, oxygen and argon and trace gases – helium, neon, krypton and hydrogen have minimal effect of weather and climate https://www.insightsonindia.com/wp- content/uploads/2021/08/Structure-Composition-of- atmosphere6.jpg COMPOSITION OF THE ATMOSPHERE VERTICAL STRUCTURE OF THE ATMOSPHERE Thermal Layers: Troposphere – lowest layer, in contact with the surface; vertical mixing of air and turbulence; depth varies in time and place Stratosphere – temperature increases with height due to the presence of ozone Mesosphere, Thermosphere, Exosphere – upper layers; temperatures very high in thermosphere Temperature patterns in the Atmosphere Temperature changes with altitude Each ‘zone’ has a specific source of heat Lower troposphere – Earth’s surface Upper stratosphere - ozone https://www.u x1.eiu.edu/~cfj ps/1400/FIG01 _019.JPG Pressure The taller the column of air above an object, the greater the air pressure exerted on that object Generally, pressure decreases upward at a decreasing rate https://img.brainkart.com/i magebk40/mJPwL6J.jpg ATOMPSHERIC COMPRESSIBILITY Compressibility is the fractional change in volume per unit increase in pressure Atmospheric Pressure at Various Altitudes, Expressed as a Percentage of Sea-level Pressure Altitude - Kilometers Altitude - Miles Percentage of Sea-level Pressure 0 0 100 5.5 3.5 50 16 10 10 32 20 1 48 30 0.1 80 50 0.001 96 60 0.00001 Barometers Effects of Pressure on Humans Bar/atmospheres (ATM) of Depth Volume of air in our bodies pressure 0 meters (surface) 1 1 10 meters 2 1/2 20 meters 3 1/3 https://chem.libretexts.org/@ api/deki/files/119775/12.jpg?r 30 meters 4 1/4 evision=1&size=bestfit&width= 603&height=281 https://i.pinimg.com/origi nals/43/5a/a5/435aa5221 97167226ca07e453516222 6.png Composition Principal gases of the atmosphere have a fairly uniform vertical distribution throughout the lowest 50 miles (80 km) of the atmosphere; this zone is called the homosphere The gases in the atmosphere above this zone tend to be layered according to their weights; this zone is called the heterosphere https://ww w2.paradis evalley.edu /ssd/geog/ outlines/un iversal_ima ges/separat e/hom_het _sphere.jpg Water vapour also varies in its vertical distribution; most is found near Earth’s surface, decreasing with altitude The ozone layer (9 – 30 miles up) is sometimes called the ozonosphere; the concentration of ozone relative to other gases is at its maximum The ionosphere is a layer (40 – 250 miles up) of electrically charged molecules and atoms (ions) Northern & Southern Lights https://travel2next.com/wp- content/uploads/southern- lights-tasmania-11.jpg https://hmxearthscienc e.com/individual_esrt_f iles/page9-1028-full.jpg HUMAN-INDUCED ATMOSPHERIC CHANGE The Ozone Layer 2020; area - 24.8 million Km2 (Oct. 2022 – 23.2 million km2 2006 – 27.5 million km2) https://assets.w eforum.org/edit or/9QrYWQg8QF 9a1oCFJBLhnvkB 9_kg- dFcjVYUXuZKaM o.png THE ELEMENTS OF WEATHER AND CLIMATE Although complex, the most important variables, or elements of weather and climate are: 1. Temperature 2. Moisture content 3. Pressure 4. Wind The controls of weather and climate are: 1. Latitude – the control latitude influences the element temperature 2. Distribution of land and water – the uneven distribution of continents and oceans is a prominent control of the elements, moisture content and temperature 3. General circulation of the atmosphere – the semipermanent pater of major winds and pressure systems dominates the troposphere and influences most elements of weather and climate 4. General circulation of the oceans – similar, although less so than with that of the atmosphere 5. Elevation – the relationship between temperature, pressure and moisture content and under the control altitude 6. Topographic barriers – they have prominent effects on one or more elements of climate by diverting wind flow 7. Storms – often they result from interactions among other climate control