The atmosphere Flashcards
How the gases of the atmosphere are kept in the atmosphere
Gravity
The air
The mixture of gases that make up the atmosphere
The amount of mass in a given volume of matter
Density
The lowest layer in the atmosphere
Troposphere
The second layer in the atmosphere from the earths surface
The sratosphere
The third layer of the atmosphere from the earths surface
The mesosphere
The fourth layer of the atmosphere from the earths surface
The thermosphere
Altitude
Height above sea level
Temperature gradient
How much temperature changes with altitude
Temperature inversion
Where the temperature increases with altitude
Main gases of the air and their %
Nitrogen ± 78%
Oxygen ± 21%
Argon ± 1%
Amounts of water vapour and carbon dioxide in the atmosphere
- A very small %
- Carbon dioxide 0.04 %
- Water vapour 0-4 %
- Warm air can hold more water vapour
Density of air in the atmosphere
- Densest at the earths surface at sea level
- Density decreases as altitude increases and the air gets thinner and thinner
- At sea level there are more gas particles inhaled with each breath than there are at altitude
Average thickness of the troposphere
10 km
Temperature gradient in the troposphere
It decreases with altitude
Layers in the atmosphere where the temperature increases with altitude
- Stratosphere
- Thermosphere
Layers in the atmosphere where the temperature decreases with altitude
- Troposphere
- Mesosphere
Water in any form that falls to the Earth’s surface
Precipitation
The layer in which clouds form
Troposphere
The cycle of processes by which water circulates between the earth’s oceans, atmosphere, and land.
The water cycle
That which is required for clouds to form.
Water vapour in the atmosphere.
Types of precipitation
- Rain
- Hail
- Snow
Why plants and animals generally live below 2km in the troposphere
- Gets too cold above
- and the air gets too thin
The temperature change for every 100m increase in altitude in the troposphere.
1 oC cooler
The extent of the stratosphere
From 10km up to about 50km altitude
Ozone
- A form of oxygen gas found in the stratosphere
- molecule consists of three atoms of oxygen (03)
The ozone layer
A band of ozone gas between 10-40 km in the stratosphere
The function of the ozone layer
- Absorbs incoming ultraviolet (UV) radiation.
- Prevents UV radiation from hitting the surface of the earth.
UV radiation
- Ultra violet radiation
- A shorter wavelength than violet light
- It is not visible to humans
The effect of ozone on the temperatures in the stratosphere
It causes the stratosphere to increase in temperature as altitude is increased
Ways that UV affects life on earth.
- Damages human health
- Affects photosynthesis
- Affects life cycles and populations
How human health is affected by excessive UV exposure
- Sunburn
- Premature aging and skin damage
- Causes skin cancer
- Causes cataracts in the eyes
- Suppresses immune system, increasing risk of illness
Cataracts
- A clouding condition of the eyes lens
- Leads to loss of vision
How UV affects photosynthesis in plants
- UV damages the chlorophyl in plant cells
- Plants are unable to photosynthise and grow
How UV affects life cycles and populations
- UV can damage many animals in their early stages of development
- This affects their ability to reproduce
- This leads to reduces population sizes
The hole in the ozone layer
- Caused by human activity
- The amount of ozone in the stratosphere decreasing
- Especially over the antartic
- So thin in places it is said to have “a hole” in the layer
The cause of reduced ozone gas in the stratosphere
- Certain gases released by human activity
- E.g. CFC’s
CFC’s
Chlorofluorocarbons
Where were CFC’s used?
- Refrigirators
- Air conditioners
- Fire extinguishers
- Spray cans
How CFC’s have been eradicated from industry?
- Montreal Protocol agreement
- Countries from around the world met and signed agreements
- Ban in production using CFC’s
Products not containing CFC’s
“Ozone friendly”
Position of the mesosphere
About 50-80 km altitude
Characteristics of the mesophere
- Extremely thin atmosphere
- Very cold
Function of the mesosphere
The few gas particles in this layer burn up meteors entering the atmosphere
Meteors
- Small space particles or rocks that burn up as they enter the atmosphere.
- Heat is due to friction with the air particles they come in contact with at high speed.
- They produce a streak of light.
- This phenomenon is also called a “shooting star”.
The location of the thermosphere
About 80-350 km altitude
What lies beyond the thermosphere?
Space
Functions of the thermosphere
- The lower thermosphere absorbs UV radiation and x-rays from the sun
- It also reflects radiowaves back to earth
Why it is useful that radiowaves are reflected by the thermosphere?
TV and radio signal can be bounced and returned to a point on Earth they would otherwise not have reached.
A structure made from transparent material in which plants are grown
A greenhouse
The greenhouse effect
The trapping of the sun’s energy in the lower atmosphere causing warmer temperatures.
The cause of the greenhouse effect
Greenhouse gases that absorb outgoing radiation
Greenhouse gas examples
- Water vapour
- Carbon dioxide
- Methane
The cause of the enhanced greenhouse effect
- Human activity causing extra carbon dioxide emissions
- Human activity causing extra methane emissions
- Climate change itself causing extra greenhouse gas emissions
Causes of increased carbon dioxide emissions
- Burning fossil fuels
- Bush fires
- Deforestation
- Desertification
Fossil fuels
- Coal, gas and oil
- Made from the remains of plants and animals that lived millions of years ago
Long term changes in the Earth’s temperature and precipitation patterns
Climate change
The main effect of an enhanced greenhouse effect
Global Warming
Global warming
An increase in the average temperature of the atmosphere
Effects of global warming
- Climate change
- Droughts and floods
- Increased extreme weather events e.g. hurricanes
- Melting ice caps and rising sea levels
- Food shortages as agriculture is affected
- Mass exctinctions as species lose habitats
Example actions to reduce greenhous gas emissions
- Restruct burning of fossil fuels e.g. use alternatives like solar
- Increase efficiency e.g. use less electricity and use public transport
- Educate people about the dangers of global warming
- Provide rewards for cutting down on greenhouse gas emissions e.g. less tax