Atmospheric system

what are the 4 layers of the atmosphere?

troposphere, stratosphere, mesosphere, thermosphere

properties of the troposphere

• extends 8-10km above poles and 15-17 above equator

• temps decrease from 25° at ground level to -40 to 80 towards the top

• most weather processes occur here

properities of the stratosphere

• 10-50km above surface

• lower temps constant then increase with altitude

  • due to solar radiation at the top

• features ozone layer which filters out harmful UV radiation

• very little water vapour, dust, and clouds

properities of the mesosphsere

• extends between 50-80km above surface

• temps fall rapidly (low as -90C) with elevation because there is no water vapour, cloud, or dust to absorb incoming radiation

• wind velocities reach up to 3000km/hr

properties of thermosphere

• atmosphere becomes thinner with elevation

• temps rise rapidly (high as 1500C) due to more oxygen in the air, which absorbs incoming radiation

what are the boundaries between each layer called

• tropopause, stratopause, mesopause,

what is insolation

amount of short wavelength solar radiation received from the sun

what is albedo

the percentage ratio between incoming radiation and the amount reflected back into space

what is terrestrial radiation

cool, long wavelengths of energy emitted by Earth

what is the natural greenhouse effect

a natural process that warms Earth’s surface as water vapour and CO2 absorb terrestrial radiation

what is diffuse radiation

the scattering of solar energy when it hits a molecule of gas which still reaches the Earth’s surface

what are jet streams

• extremely fast moving air, reaching up to 230km/hr

• located in the troposphere

• helps rapidly transfer heat energy

what is the Coriolis effect?

• the curving of an objects or fluids path due to the Earth’s rotation

Features of the hadley cell

• occurs at 30° north and south

• descending air at equator causes high pressure system

  • clear skies and dry, stable conditions

• Trade winds move air back towards equator to replace rising air

features of the ferrel cell

• some of the warm, dry air from Hadley cell continues towards the poles, picking up moisture from the ocean

• meets cold air from the poles at 60° north and south

• this caused the warm, moist air to rise, creating a low pressure system and thus unstable weather

features of the polar cell

• at the poles, air is cooled and sinks, forming a high pressure system called the Polar Highs

• cold air moves away from the poles until it meets the warm air of the Ferrel cell

which way do high and low pressure systems spin in the southern hemisphere

features of low pressure systems

• called cyclones, and it has;

  • formed over warm topical water

  • water ocean → evaporation → clouds → low air pressure pulls clouds in and they begin to rotate

  • the ‘eye’ is the center and is calm due to cool sinking and is generally 40km but ranges from 10-100km

  • light wind and clear skies

  • cyclone gets weaker and fades out over land because it doesn’t have warm water to evaporate

• isobars are spaced closely together

• consists of warm, rising air

• produces windy, rainy, and unstable weather

features of high pressure system

• called highs or anticyclones

• isobars are spaced widely apart

• consists of cold, descending air

• produces stable and dry weather

insolation variations

• latitude

• earth’s revolution and rotation

  • length of day and night

• atmosphere components

• distribution of continents and oceans

• topography

what does a synoptic chart/weather map do

• records atmospheric conditions in a particular place at a particular point in time

• provides air pressure, location of air masses, extent of cloud cover, wind speed and direction, and rainfall

• the lines on synoptic charts are called isobars, which are lines of equal amount of barometric pressure

signs of a low pressure system on synoptic chart

• isobars close together

• hPa less than 1013

• literally says LOW

signs of high pressure system in synoptic charts

• isobars far apart

• hPa higher than 1013

• literally says HIGH