B: Atmospheric Environments Flashcards
(25 cards)
State the 5 determinants of climate
- Latitude
- Position relative to continents and oceans
- Position relative to global circulation model
- Altitude
- Local geographical features
Why does latitude effect climate
- The further you are from the equator, the cooler the temperature
- This is because at higher latitudes suns rays are dispersed over a larger area, meaning the same amount of energy is spread over a greater area
- Also in polar regions suns rays must travel further, so have a higher chance of being absorbed by the atmopshere
Why does position relative to continents and oceans effect climate
-The sea has a high specific heat capacity so acts as a moderator on the temperature. It decreases the annual temperature range
Why does position relative to global circulation effect climate
- Temperature of wind is determined by area of origin and characteristics of fetch
- Warm ocean currents lead to an increase in air temperature
Why does altitude effect climate
- The higher the altitude the lower the temperature
- This is because at higher altitudes the air is less dense so it can’t hold as much heat
- Also because at higher altitudes there is a smaller area of land so air is heated less by conduction
Why do local geographical features effect climate
- Aspect creates shadows, leading to a decrease in temperature. in the Northern hemisphere, north facing slopes are cooler
- Cloud cover reduces solar radiation and increases reflection and scattering. It also reduces length of day, but also increase heat retention at night
Composition of the atmopshere
Troposphere, Stratosphere, Mesosphere, Thermosphere
4 factors controlling the amount of incoming solar radiation
- Solar Constant
- Distance from the Sun
- Altitude of the sun in the sky
- Length of day and night
3 vertical transfers of energy
Direct and Diffuse Radiation, Scattering and Reflection
Vertical Stores
Ozone, atmospheric gases, clouds and buildings
Vertical Outputs
- Terrestrial Infrared Radiation
- Convection
- Conduction
- Latent Heat
- Reflected Radiation
- Albedo
What are the 2 horizontal transfers are what are there percentages of global redistribution
Winds (75%) and Ocean Currents (25%)
Why do we need horizontal energy transfers
Because there is a surplus of energy at the tropics and a deficit at polar areas, the redistribution prevents the equator becoming too hot and the Poles too cold
What are the 3 cells in the tri-Cellular Model and where are they located
Hadley=0-30 N&S
Ferrel=30-60 N&S
Polar=60-90 N&S
Describe the circulation of the Hadley Cell
- As the sun is always in the sky at the ITCS, the ground heats up rapidly during the day
- Hot air rises at the equator
- An area of low pressure develops
- The rising air cools as it ascends
- Condensation begins to form and clouds are produced
- At high altitudes the air moves pole-ward
- At around 30 degrees the colder air begins to sink towards the earths surface
- This process creates high pressure at the surface
- On reaching the ground, some air returns to the equator via trade winds
What is air pressure and what is it measured in
The density of air measured in millibars
Characteristics of Low Pressure (NH)
- Air is rising and rotating in an anti-clockwise inward direction
- Associated with unsettled weather
Characteristics of High Pressure (NH)
- Air is sinking, and rotating in a clockwise outward direction
- Associated with gentle winds and settled weather
Which way do ocean current move
From areas of surplus (equator) to areas of deficit (Poles). Clockwise in the NH and Anticlockwise in the SH
What is the name of the ocean current that warms the UK
North Atlantic Drift
What is the name of the cool current off the west coast of South America
Humboldt
Why do ocean currents form (WIND)
-The prevailing winds create friction with the surface water
, setting up ocean currents
-The huge size of the Atlantic and Pacific oceans allow these patterns to form
-The trade winds and Westerlies drive the patterns
-The Coriolis force causes them to be deflected in a circle
Why do ocean currents form (DENSITY)
- Uneven heating produce density differences in the ocean
- Cold dense polar water sinks, then spreads towards the equator, and pushes up the less dense water which moves off to the Polar areas
What’s the difference between spatial differences and temporal differences
Spatial=vary over space and location
Temporal=Varies over time
