lec 6 global energy movement

fluid at higher pressure will try to

move towards area with lower pressure

if an entire air column is warmed it will

expand primarily vertically

after warm column expands, its pressure is

greater than the comparatively cold column, so air will move from warm to cold column

now that warm column has lost some mass, surface pressure under it

decreases, while under colder one pressure is comparatively higher

direct circulation

air flows from cold to warm at low levels and the opposite at high levels

landform-driven air movement

air cools as it is forced upwards due to decreasing pressure

saturation

condensation to liquid because of high-enough amount of gas in volume

for water to remain liquid, gas around it must be

saturated with humidity, otherwise there will be evaporation again

saturation increases with

temperature

if subsaturated air cools enough it will become

saturated, then supersaturated

clouds form most commonly when

warmer air from below is rising and coolings

hadley cell

convection cell beginning at the equator and descending at 30º N and S

ferrel cell

convection cell sinking at 30º and rising at 60º

polar cell

convection cell beginning at 60º and descending at the poles

ferrel is driven mainly by

movement of the hadley and polar cells, weaker and more variable

surface ocean currents

driven by surface winds, landforms deflect them into gyres

deep ocean currents

driven by water density differences from temperature and salinity

ocean salinity comes from

minerals weathered from land; evaporation, and rain

heat energy in the ocean is driven by

solar radiation, re-emitted radiation, and surface currents

ice formation in polar regions increases

water salinity since salt is excluded from the ice

saltier water by the poles sinks, which

drives deep ocean circulation