Conditions for life on earth Flashcards
What is the water sphere called?
Hydrosphere
What is the gas sphere called
Atmosphere
What is the rock sphere called
Lithosphere
What is the life sphere called
Biosphere
What is sufficient Thor the earth to retain an atmosphere
The mass of earth and it’s resulting force of gravity
Which gases did the early atmosphere provide for making biological molecules
Carbon Dioxide, methane and nitrogen
Where did these early atmosphere gases come from
Volcanic activity
What maintained liquid water
Atmospheric pressure and temperature
What is atmospheric pressure
The pressure exerted by the weight of the atmosphere
What would happen to water if atmospheric pressure was too low
Liquid water would boil well below 100 degrees
What would happen to water if the temperature was too low
Liquid water would turn to ice
What would happen to water if the temperature was too high
It would turn to gas
Why is liquid water important
It’s essential for life - physiological solvent, transport, coolant and it provides aquatic habitats
What does physiological solvent mean
Dissolving chemicals to allow biological reactions in solutions to occur
What is a coolant
Eg. Sweating
What is anomalous expansion
Where water expands instead of contracting when the temperature goes from 4 degrees to 0 degrees and it becomes less dense
What does anomalous expansion on freezing water create
An insulating later that prevents many water bodies from freezing solid
What is a specific heat capacity
The amount of energy needed to change the temperature of 1kg of the substance by 1 degree
What does high specific heat capacity of water mean
That water bodies change temperature slowly, creating more stable habitats
What is the amount of solar energy reaching a certain area called
Insolation
What is a suitable temperature range controlled by
Incoming insolation, it’s absorption by the earth’s surface and it’s behaviour in the atmosphere
What is the measure of the ability of surface to reflect light called
Albedo
What does a surface need to do to heat up
Absorb lots of energy
Why does ice have a cooling effect on the earth’s climate
Because it has a high albedo and reflects a great deal of solar energy without absorbing it
Why do darker surfaces have a low albedo
Because they reflect little sunlight and absorb most of it
What happens to some of the energy when sunlight is absorbed
It’s reradiated as longer wavelength radiation