Weather And Climate Flashcards
Composition of atmosphere
78% nitrogen
20% oxygen
0.04% co2
Others include water vapour and argon
Troposphere
Later which extends up 8-17km above the earths surface where temperature decreases with height
Where weather processes occur
Tropopause
Boundary between the troposphere and the stratosphere
Ceiling to convection currents and forms a temperature inversion
Upper limit to earths weather system
Stratosphere
Extends up to 50km above earths surface tempearture increases with height
Free of dust and cloud
Absorption of UV by ozone
Global warming by humans linked to changes
Define atmosphere
Mixture of transparent gases held to the earth by gravitational force
Stratopause
boundary between the stratosphere and the mesosphere
Mesosphere
Layer which extends 50km above the Earth’s surface where temperature decreases with height
Mesopause
boundary between the mesosphere and the thermosphere
Thermosphere
Layer which extends up to 100km above the earths surface where temperature increases with height
What is the atmospheric heat budget?
Balance between incoming solar radiation (insolation) and outgoing radiation
what 4 factors determine the amount of insolation?
Solar Constant
Distance from the Sun
Altitude of Sun in the sky
Length of day and night
What is the solar constant?
rate at which the suns energy is received at the top of the atmosphere, when the sun is at its mean distance from the Earth and the atmospheric absorption has been accounted for
effects long term climate
what percentage can the earths orbit have on the solar constant
6
How does altitude affect insolation?
equator receives maximum insolation whereas areas at higher latitudes receive less and there is a greater area for the sun to heat
Length of day and night on insolation
23.5 tilt results in polar regions receiving almost no insolation in winter
Does the Earth’s surface have a net gain or deficit of energy and what does this result in?
Net gain, results in horizontal heat transfers as polar regions have a deficit
Atmosphere net gain or deficit of energy and its effects
Deficit so results in vertical heat transfers
What % do ocean currents transfer in heat
20
What % do winds distribute in heat
80
Vertical heat transfers
radiation, conduction, convection and the release of latent heat
What is albedo effect?
ratio of incoming radiation to the amount which is reflected
What % of incoming radiation reaches the Earth’s surface`
24
why does only 24% reach the Earth’s surface
absorption by clouds, ozone, co2 and dust
reflection by clouds and scattering
What is wind?
horizontal movement of air across the Earth’s surface as a result of differences in pressure
