water and carbon cycles Flashcards
def atmosphere
a layer of gases surrounding a planet that is held in place by gravity
def hydrosphere
the combined mass of water found on, under, and above the surface of a planet
def cryosphere
these portions of the earths surface where water is in solid form. eg. sea ice, river ice, snow cover, glaciers, ice caps and sheets, frozen ground ( permafrost )
def geosphere
collective name for the lithosphere, the hydrosphere, the cryosphere and the atmosphere
def pedosphere
outermost layer of the earth that is composed of soil and subject to soil formation processes
def biosphere
the global sum of all ecosystems
def magnetosphere
the region of space surrounding the earth in which charged particles are controlled by the magnetic field
def lithosphere
rocky, rigid outermost shell of our planet
describe the water cycle ?
water evaporates from oceans and condenses into clouds in the atmosphere, then clouds precipitate like rain ,snow ,hail. the surface runoff infiltrates rocks and groundwater forms, which eventually flows back into oceans
describe the carbon cycle ?
the carbon in the atmosphere is absorbed by plants in photosynthesis and stored. animals eat the plants and
why do we use models ?
models simplify complex things so that we can begin to understand how they operate
what are the advantages and disadvantages of using models ?
ad = simplify complex concepts
allow for interpretation
clarify systems and sequences
dis = can be over simplified
may become too complex (defeats the purpose)
can create misconceptions
what is a system ?
a set of things working together as parts of a mechanism or interconnecting network: a complex whole
what is an open system ?
a system that freely exchanges energy and matter with its surroundings
what is a closed system ?
a system that exchanges with its surroundings not matter
what is an isolated system ?
does not exchange energy or matter with its surroundings
what is dynamic equilibrium and how is it altered ?
the balance between inputs and outputs in systems, a change in a system can cause the equilibrium to shift causing a change in stores (feedback)
what is positive feedback ?
where the effects of an action are amplified or multiplied by subsequent or secondary effects
what is negative feedback ?
where the effects of an action are reduced by its subsequent knock on effects ?
what are the four spheres ?
hydrosphere, biosphere, lithosphere, atmosphere
what is evaporation
?
when liquid changes phase into a gas
caused by solar radiation
the rate is dependent on the amount of solar energy available, water available, humidity and temperature
what is condensation ?
gas –> liquid
as air cools it is able to hold less water, when its cool enough it becomes saturated (dew point)
excess water is converted to liquid water on a surface ( condensation nuclei )
what is latent heat ?
energy released or absorbed by a substance during a change in its physical state (phase)
eg. evaporation removing heat from surroundings or condensation adding heat to surroundings
where is the the global water stored ?
96.5 % oceans , 2.5% freshwater and 0.9% other saline water
what is the earths major stores of water ?
atmospheric water - water found in the atmosphere: water vapour and liquid water (cloud and rain droplets) and ice crystals
terrestrial water - groundwater, soil moisture, lakes, wetlands and rivers
oceanic water - water contained int the earths oceans and seas but not including such inland seas eg. caspian sea
cryospheric water - the water locked up on the earths surface as ice
name the processes in drainage basin system
precipitation , infiltration ,surface runoff, throughflow (water moving through the soil), stemflow, percolation, evaporation and transpiration, interception, deposition and erosion
what are the components of a drainage basin system ?
watershed boundary - the outer edge of the basin where any precipitation falls will flow toward the main river
source - origin of the river
tributaries - smaller rivers that flow into the main river
confluence - the point where two rivers meet
main river channel
floodplain
mouth
groundwater and soil water storage
what is water balance ?
the difference between the inputs and the outputs (the overall change in storage) in the drainage basin
the amount of water will increase when precipitation exceeds runoff and evapotranspiration
the amount of water will decrease when runoff and evapotranspiration exceeds precipitation
what is the water balance equation ?
P = Q + E +- S
precipitation = runoff/discharge + evapotranspiration + change in storage
what is the soil moisture budget ?
the change in the amount of water stored in the soil throughout the year
factors involved are precipitation and potential evaporation
what is potential evaporation ?
the amount of evapotranspiration that could occur if there was sufficient water available in the system, this is effected by the temperature
what is a river regime ?
the variability in river discharge throughout the course of the year in response to precipitation , temperature, evapotranspiration and drainage basin characteristics
what is river discharge ?
the volume of water passing a specific point in a given time
