3. General Circulation Flashcards
What is the ozone hole?
depletion of O3 related to the atmospheric chemistry, exacerbated by bromine, chlorine, and chlorofluorocarbons (CFCs), Montreal Protocol, as it thins more UV rays come through - burn easier, annual minimum during the spring months
What is the Montreal Protocol?
1987: phased out the productions of numerous substance related to ozone depletion
What is latent heat flux?
energy that is stored in water vapor as it evaporates, strongest where there’s surface moisture and a strong gradient between surface and air temp and humidity
what is sensible heat flux?
dry air convection, strongest where there’s gradient in temp between the surface and air temp, conduction and advection, and radiation
What is specific heat?
amount of hear per unit mass required to raise temps by 1C
- high = object warms and cools slowly (ocean, rivers, lakes)
- low = object warms and cools fast (land)
What is the Coriolis effect?
describes the apparent deflection of objects moving in a straight path relative to earth’s surface - northern hemisphere objects are deflected to the right from place of origin; southern hemisphere objects are deflected to the left from place of origin
- earth rotates west to east (counter-clockwise)
- 839km/hr at poles & 1674km/hr at equator
What is convergence?
hot air rising is associated with low pressure, involves low pressure and high pressure areas, law of mass continuity
Explain a low-pressure area.
- low/depression; a region where atmospheric pressure is lower than that of surrounding locations.
- rising air; cools area, makes clouds and brings rain
What is the law of mass continuity?
empty spaces aren’t tolerated, air always moves to fill them in causing rotational cycles
Explain high-pressure areas.
- high/anticyclone; region where atmospheric pressure at the surface is greater than its surrounding environment.
- sinking air; warms area, clear sky, brings drier air
Why do large storms spin?
- Coriolis effect, low pressure at the middle of the storm - high pressure comes rushing back pulling is to the right (counter clockwise) - northern hemisphere
- tropopause is more dense because air is cooler causing molecules to condense making it shrink - still same size in mass
Draw general circulation of Earth.
*
What is the ITCZ?
- InterTropical Convergence Zone
- relatively little wind (equator), storms are built upwards and not in fronts like other parts of the world
Explain the preferential pressure patterns.
- the Hadley cell moves N&S depending on the time of the year
- south - July: Aleutian low (Alaska), Pacific high (Cali), Azores high (Golf last > Africa), Icelandic low (Iceland), & Siberian high (Asia)
- north - January: Pacific high (Cali), Azores high (Golf last > Africa), Icelandic low (Iceland), & Tiberian low (Asia)
What is the polar jet stream?
current of fast moving air in the upper troposphere at boundary of polar front
- may be thousands of miles long but only 10s of miles wide
- develops aloft and leaders above high pressure anticyclones (ridges) and below low pressure cyclones (troughs)
