Atmosphere Flashcards
What is the earth’s atmostphere?
A blanket of gases that contains solid particles (Ie volcanic dust and blown soil) and remains attached to the earth’s surface due to gravitational force.
What is the atmosphere a mixture of?
Oxygen (21%), Nitrogen (78%), Co2 (0.057%) and other gases such as hydrogen, helium, neon, xeyon and ozone. As well as water vapour.
Where are the atmospheric gases densest?
earth surface
These gases in the atmosphere get less dense with increasing height. What percentage of the atmosphere by weight is in the lowest 15 km (9 miles) above the surface
90%
How thin is the skin of air that keeps all life on earth alive?
very thin
What are the 2 most important greenhouse gases?
Water vapor and CO2
Why are water vapour and CO2 the most important greenhouse gases
due to their ability to trap outgoing infra-red radiation, thereby keeping the surface of the Earth warmer than it should be.
In the troposphere temperatures decrease by what every 1000m?
6.4 Degrees
Why does the troposphere decrease by 6.4 degrees every 1000m?
In the troposphere temperature decreases by 6.4°C for every 1000m in altitude, this is because is warmed by incoming solar radiation which in turn heats the air by convection.
What does the troposphere contain?
Atmospheric water, cloud dust, and pollution
The upper limit of the troposphere is called what?
tropopause
What is the stratosphere categorized by?
The stratosphere is characterised by a steady increase in temperature caused by the ozone layer-
What does ozone absorb?
Ozone absorbs incoming (UV) radiation very efficiently.
The upper limit of the stratosphere is called what?
stratopause
What happens in the mesosphere?
Temperatures fall rapidly with an increase in height in the mesosphere as there is no water vapour, clouds, dust or ozone to absorb the incoming radiation.
Mesosphere layer has the strongest what?
WIND
Mesosphere layer has the lowest what?
temperatures
Temperature’s rise rapidly in the thermosphere due to an increase in what?
atomic oxygen which absorbs incoming radiation
How high can temperatures get in the thermosphere?
2,500 degrees
The upper limit of the Atmosphere is called what?
exosphere
What are the main gases in the exosphere?
light gases, hydrogen, helium, co2, and atmospheric oxygen
Energy from the sun heats the atmosphere and the oceans. The energy is transmitted as short wave incoming radiation what is the short word for this type of radiation?
Insolation
What percentage of the earth’s energy penetrates the atmosphere to reach the surface of the earth
less than 50%
What percentage of the heat is absorbed by the earth’s surface?
46%
What percentage of the heat is reflected back by the earth’s surface?
4%
What percentage of the heat is reflected by the clouds?
20%
What percentage of the heat is scattered by gas?
6%
What percentage of the heat is absorbed by dust, water vapor, and other gases?
16%
What percentage of the heat is absorbed by the clouds?
3%
What percentage gets released as long wave energy from the surface into space again?
6%
What is the albedo effect?
Reflection of heat or by snow or ice!
94% of clouds act as a blanket absorbing and reflecting. What 2 things do clouds do?
reradiation from the clouds
clounds heat from earth surface
As the ground warms up it radiated energy back into the atmosphere - this outgoing energy is called What? .
terrestrial radiation and is long wave or infra red
Most of the terrestrial radiation is absorbed by H2O and what?
CO2.
What is scattering?
Scattering: this occurs when light passes through a transparent medium that contains small obscuring particles; therefore, light is scattered (ie dust)
What is reflection?
Reflection: Heat can be reflected by clouds, atmospheric gases, and the earth’s surface. Most are clouds, but much is reflected by the ice and snow on the surface. Together, reflection and scattering form what is called albedo (reflectivity of a surface) and is responsible for a 30% radiation loss.
What is absorbtion?
Absorption: The atmosphere absorbs a relatively small amount of solar radiation, but a large amount of terrestrial radiation. Most of it is absorbed by CO2 and water vapor.
