water cycle, water on planet earth Flashcards
what is the hydrosphere?
water on or close to the earths surface
what is atmospheric water?
water found in the atmosphere mainly water vapour
what is cyrospheric water?
water that is locked up in earths surface as ice
what is oceanic water?
water contained in the earths oceans but not inland seas
what is terrestrial water?
three main types
ground water - strata
surface water - lakes
soil water - air spaces of soil
what could effect climate change?
changing amounts of atmospheric water
what percentage of the earths surface do oceans cover?
72%
hwat percentage of water do the oceans contain?
97%
what percentage of the oceans have been explored?
5%
what does the salts in oceans allow it to do?
stay as a liquid below zero degrees
why has the ph of oceans decreased?
due to increase in atmospheric carbon
what are the five forms of cryospheric water?
ice caps ice sheets alpine glaciers permafrost sea ice
what is sea ice/
formed from ocean water when temperature drops lower than zero
does sea ice raise sea level?
n
why doesn’t sea ice raise sea level?
because it forms from ocean water
what are ice shelves?
form when ice sheets and glaciers move out to sea
how are ice bergs formed?
chunks of ice that break off glaciers and ice shelves
do ice bergs change sea level?
only when they first leave land and push into the water but not when they melt
what are ice sheets?
mass of glacial land extending more than 50,000km
where are the two major ice sheets?
covering most of greenland and antarctica
what percentage of freshwater do the ice sheets on greenland and Antarctica hold?
99% of earths fresh water
how far does the greenland ice sheet extend?
1.7 million km3
how do ice sheets form?
when snow from winter does not fully melt in the summer and over thousands of years layers of ice pile up and compress
how thick is the antarctica ice sheet?
2km
if the antarctica ice sheet melted how much would sea level rise by?
60m
what are ice caps?
thick layers of ice that extend less than 50,000km2
which form extends more than 50,000km2?
ice sheets
where are ice caps found?
in mountainous areas
which way do ice caps flow?
outwards, covering everything in their path
what are alpine glaciers
thick masses of ice found in deep valleys or in upland hollows
what is permafrost?
defined as ground that remains below zero degrees for at least two consecutive years
when permafrost melts what does it release and why is this a problem?
releases large amounts of carbon dioxide and methane, potentially affecting global warming
what are the four broad classes terrestrial water can fall into?
surface water
ground water
soil water
biological water
what is surface water?
free flowing water of rivers as well as the water of ponds and lakes
what doe rivers act as?
a store and a transfer of water
what is groundwater?
water that collects underground in the pore spaces
what is the water table defined as?
the depth at which rock becomes completely saturated with water
how is the amount of groundwater decreased?
by extraction for use in irrigation for agricultural dry land
what is soil water?
held together with air in unsaturated upper weathered layers of the earth
how does soil moisture affect climate?
plays a part in the evaporation
what is biological water?
water stored in all biomass
how can climates become more desert like linked to biological water?
if vegetation is cut down then there is no evaporation so no water in the atmosphere making the air very dry
what states of water does atmospheric water have?
all three
what will a small increase in water vapour lead to?
an increase in atmospheric pressures
what can hot air do but cold air can’t?
hold more water
