water cycle - factors driving change in magnitude of water stores Flashcards
what forms does water exist in on earth
liquid, gas and solid
when changing a state what is released/absorbed in order to do so?
energy in the form of latent heat
what is it called when a solid turns into a gas?
sublimation
when does evaporation occur
when energy from solar radiation hits the surface of water and land and causes liquid water to change into a gas
what does the rate of evaporation depend on?
amount of solar energy
availability of water
humidity of air, if close to saturation point it will be slower
temp of air, warm air holds more
who do terrestrial plants lose water?
through transpiration
what is transpiration?
water is transported from the roots to its leaves and then lost through the pores
what happens when water evaporates?
it uses energy in the form of latent heat, absorbing it, cooling the surroundings
why does condensation occur?
it occurs when water n atmosphere cools to its dew point
what is the dew point temperature?
involved in condensation, this is where as cool air is cooled sufficiently it will get to a saturation point
what do water molecules need for condensation?
something to condense in that is below the due point temperature
what happens if the surface use to condense on is below zero degrees?
sublimation will occur, instead of water it will turn into frost or ice
condensation is the direct cause of what?
all forms of precipitation
what are the two main cyrospheric processes?
ablation and accumulation
what is ablation?
the removal of snow or ice through melting
who many glacial periods have there been in earths history?
five
when did the most recent glacial period start?
2.87 mil years ago
what is an interglacial period?
when ablation exceeds accumulation
when is permafrost formed?
when air temperature is low enough that they freeze any soil and groundwater present, must be preen for two consecutive years
how do glacial period disrupt the hydrological cycle?
lower sea level as water is frozen
how do clouds form?
when warm air cools down, causing water vapour in it to condense into water droplets which gather as clouds
what are things that can cause warm air to cool leading to precipitation?
- other air masses (warm air is pushed upwards as less dense)
- topography (orographic precipitation)
- convection (sun heats up ground and it evaporates creating column of warm air?
what is convection precipiation?
when the sun heats the ground and any water evaporates creating a column of warm air that rises
what is could condensation nuclei?
tiny particles such as soot that allow water to condense creating a cloud
water droplets are too small to form clouds on their own
