Hydrosphere 2 session 2 Flashcards
How can liquid water be described?
Chaotic
Highly polar (electrical charge)
What does the electrical charge within water create?
loose hydrogen bond between +O and -H
What does the loose H bond in liquid water cause?
adhesive/ sticky
surface tension
What happens to water density as it freezes?
it looses density
What happens to waters structure as it freezes?
rigid structure- hexagonal structure
more space between molecules
What is the environmental benefit to liquid water being sticky and has surface tension?
allows for higher plants (trees form lowest trophic level)
Water able to move in plants by capillary action
What state of water is very rare in the universe?
liquid water
What is the unique behaviour of water?
when cooled to 4*c liquid water contracts colder then this it begins to expand again
How much will water expand upon freezing?
9%
What does ice having a lower density allow it to do?
float on top of liquid water
What is the effect of having ice floating on top of water?
profound effect on albedo as lighter surface sits above darker
What are the main reservoirs within the hydrological cycle?
Atmosphere
Hydrosphere
Biosphere/ surface water
Groundwater
What is an example of solid water that can be found on another planet in the solar system and what is it composed of?
Martian ice cap
H20 and CO2 ice
Where has ice been recently discovered within our solar system?
surface of our moon within the regolith
What is Venus like at present and what was it like in the past?
Present- 480*c, High CO2 driving runaway GHG effect
Past- when sun weaker liquid water
How do Jupiter’s moons show ice and potential liquid water evidence?
Ganymede is frigid has thick ice ‘lithosphere’
Europa may has vast underground ocean giving fracture texture on surface
What is the proportion of ocean to fresh water?
97.5% ocean
2.5% fresh
How is the global 2.5% fresh water split between frozen and unfrozen?
Frozen (glaciers and ice caps)- 74%
Unfrozen- 26%
What is the proportion of unfrozen freshwater which is surface or ground water?
Groundwater- 98.5%
Surface water- 1.5%
What are the 2 types of aquifer?
Confined
Unconfined
What is an unconfined aquifer?
permeable rock fed by surface water usually water within soil/ rock particles
What is a confined aquifer?
an impermeable rock that is dissolved forming cavities which water will collect in
What is a karst system?
type of landscape where the dissolving of the bedrock has created sinkholes, sinking streams, caves, springs, and
What types of rock are karst systems related to?
limestone
marble
gypsum
What is the difference between stalagmites and stalactites?
stalactites- ceiling
Stalagmites- floor
How do stalagmites form?
limestone dissolves
water becomes super saturated in CaCO3 and CO2
When reach cavity CO2 degases and CaCO3 precipitates
What can stalagmites be compared to as for a paleoclimate reconstructor?
ice cores
but no gas bubbles contained
What has stalagmite evidence shown there is a link between?
Major drying mid Holocene in SE Asia linked to Green Sahara termination
What might the link between drying of SE Asia and Green Sahara termination have meant for human settlement characteristics?
Potential driver of transition from hunter gatherer to cereal farmer
What was Angkor Wat called?
the hydraulic city
Why was Angkor Wat called the hydraulic city?
built on a vast water management system of canals, reservoirs and tanks that provided a constant supply of water for crops
What was the size of Angkor Wat?
one of the largest cities on the planet with 1 million population
What was used to show the full scale of Angkor Wat?
Lidar- laser scanning
How are stalagmites and tree rings linked for Angkor Wat?
Show evidence of a prolonged drought period??
What evidence is there in Angkor Wat that there was a failure of the water management infrastructure?
Bridges over canals repaired with stones from temple showing rushed job with little proper planning
