Atmosphere and Weather Flashcards
(153 cards)
What is incoming solar radiation?
Where shortwave UV insulation is the only energy input
What is incoming solar radiation affected by?
The amount and type of cloud & the sun’s angle
What happens to the incoming solar radiation?
1) around 5% is scattered by atmosphere
2) 24% reflected into space by atmosphere
3) 23% absorbed by atmospheric gases
4) 48% absorbed by Earth’s surface and heats it
What is reflected solar radiation?
The proportion of energy that is reflected back to the atmosphere (aka albedo)
What is true about lighter materials and reflected solar radiation?
Those materials have higher albedo values and therefore reflect more radiation energy
What is planetary albedo?
The proportion of insulation scattered and returned to space by earth
What is the process of surface/subsurface absorption? (4)
1) since darker surfaces absorb more radiation, energy is likely to be transferred o lower layers through conduction
2) if conduction is possible, surface will reman cool has heat is transferred to soil/bedrock
3) conduction is encouraged hen moisture is present
4) heat is released back to surface at night (offsetting night-time cooling)
What is the process of long wave radiation? (3)
1) since earth is a cold body, it emits long-wave radiation back to space
2) long-wave radiation is easily absorbed by greenhouse gases (water & CO2) and by clouds then heat is returned to the surface (this overall process is the greenhouse effect)
3) heat loss is greatest on cloudless nights
What is the daytime budget equation?
Insulation — (reflected insolation + surface absorption + sensible heat transfers + latent heat transfers + long-wave radiation)
What is the night-time budget equation?
Stored energy — (latent heat transfers + sensible heat transfers + long-wave radiation)
What happens to the cloud during the day?
Clouds ave a net cooling effect due to their albedo value causing insolation to be reflected to space
What is true about cirro clouds in cloud effects?
They allow insolation to pass through but not long-wave radiation
What is true about cumulonimbus clouds?
They do not heat or cool well
What is true about low thick stratus clouds?
They reflect 80% of insolation, keeping Earth’s surface cool
What happens to the clouds at night? (3)
1) thick clouds act as an insulating layer
2) they absorb and re-radiate long-wave radiation which keeps nights warm
3) warm clouds also emit long-wave radiation out to space
What is a part of sensible heat transfer (SHT)?
Convection and conduction
What is the process of convection (SHT)? (4)
1) thin air layer heated above surface (Poor conductor)
2) molecules vibrate more and gas is less dense so rises
3) air cools, becomes denser and falls to replace rising air
4) at night, air might sink in higher latitudes and advection may occur
What is conduction (SHT)?
Is the heat transfer between the ground and the air when they are in contact
What is the process of latent heat transfer? (3)
1) occurs when water evaporates to water vapour or ice melts into water vapour
2) heat required to change state is absorbed from the air leaving less energy to heat the surface
3) latent heat of condensation increases the speed and extent f convection
What is the process of evaporation? (2)
1) water molecules gain enough energy from surrounding air to change state to gas and leave the surface
2) overall less energy is left at the surface so the surface and air cool
What is the process of the formation of dew? (4)
1) water saturated air comes to contact with an object
2) object has cooler temperature than air’s dew point
3) water vapour condenses into liquid form
4) latent heat is released during condensation, adding heat to the ground
What is the process of absorbed energy returned to Earth?
Greenhouse gases absorb re-radiated long-wave radiation and atmosphere warms
What is the process of surface temperature change? (3)
1) during the day, the surface s heated by radiation, conduction and convection
2) surface air moves slow due to friction, then air heats up and rises due to convection
3) at night, ground is cooled by lack of radiation then heat from soil and rocks rise to heat surface
What is excess in the topic of the latitudinal radiation pattern?
Is the positive radiation budget in the tropics and it occurs because insolation is so concentrated