Geography notes I
Paper 1 - Physical
Water and Carbon Cycles
Introduction
a system is a set of interrelated components working together towards some kind of process
each system has certain characteristics…
flows stores
photosynthesis plants
infiltration bodies of water
transpiration soil
inputs outputs
precipitation evaporation
seeds carried by wind seed dispersal
leaf falling water soaking through soil
types of systems include…
1. closed systems - where materials are limited and does not involve any external factors,
and energy can transfer across boundaries
2. open systems - where materials and energy can be transferred across boundaries into the
surrounding environment
dynamic equilibrium : when the inputs and outputs are balanced
Geography notes I 1
, unbalanced systems = issues arise = feedback
positive feedback : amplified effect
(i.e. global temp rise → increased ocean temp → dissolved CO2 released → more CO2
in atmosphere → global temp rise…)
negative feedback : mitigated effect
(i.e. increase in atmospheric CO2 → more plant growth → reduces atmospheric CO2)
subsystems -
cryosphere : frozen water on earth - ice caps, glaciers
lithosphere : earth’s outer layer - crust, upper mantle → tectonic processes & landforms
biosphere : zone of life - ecosystems and living organisms → biodiversity, human factors
hydrosphere : water on earth - oceans, glaciers → hydrological processes, water
management
atmosphere : layer of gases → weather, climate change
interlinked by the cycles and processes
matter & energy move between the subsystems
changes that occur in one subsystem could affect the others
Water cycle
global distribution and size of major stores …
cryosphere : 69%
lithosphere : 30%
hydrosphere : 0.3%
atmosphere : 0.04%
water is continuously cycled between the different stores
the transfers…
Geography notes I 2
, condensation deposition
evaporation sublimation
melting precipitation
infiltration baseflow
drainage basins
an area of land where all the surface water drains into a common outlet
defined by natural hydrographic boundaries - ridges, hills, mountains - and vary widely
in size
rainfall is collected in streams, rivers, lakes, groundwater, etc. in the basin’s outlet
influences flow of water, sediments and nutrients across landscapes
transfers:
infiltration groundwater flow surface runoff
percolation throughflow etc…
stores:
lakes channel storage soil storage
interception absorption groundwater
water balance - how much water is stored in the basin
P = Q + E +\- S
P= precipitation Q= runoff
E= evapotranspiration S= change in storage
dry season → deficit\ shortage
recharges in next wet season
displayed on a water balance graph
hydrographs
Geography notes I 3
, show how a drainage basin responds to a period of rainfall & river discharge
used to plan for floods and drought
features include….
peak rainfall
peak
discharge
rising limb
falling limb
base flow
lag time
basins with rapid runoffs and not much storage capacity = short log time, high peak discharge
→ “flashy” hydrograph
basins with slow runoffs and high storage capacity = high log time, low peak discharge
→ “delayed” hydrograph
amount of runoff & shape of hydrograph depends on…
size of basin ground steepness
shape of basin rock & soil type
factors affecting the size of stores/flows :
human: physical:
farming practices storms & precipitation
land use/deforestation seasonal changes
water abstraction
Geography notes I 4
Paper 1 - Physical
Water and Carbon Cycles
Introduction
a system is a set of interrelated components working together towards some kind of process
each system has certain characteristics…
flows stores
photosynthesis plants
infiltration bodies of water
transpiration soil
inputs outputs
precipitation evaporation
seeds carried by wind seed dispersal
leaf falling water soaking through soil
types of systems include…
1. closed systems - where materials are limited and does not involve any external factors,
and energy can transfer across boundaries
2. open systems - where materials and energy can be transferred across boundaries into the
surrounding environment
dynamic equilibrium : when the inputs and outputs are balanced
Geography notes I 1
, unbalanced systems = issues arise = feedback
positive feedback : amplified effect
(i.e. global temp rise → increased ocean temp → dissolved CO2 released → more CO2
in atmosphere → global temp rise…)
negative feedback : mitigated effect
(i.e. increase in atmospheric CO2 → more plant growth → reduces atmospheric CO2)
subsystems -
cryosphere : frozen water on earth - ice caps, glaciers
lithosphere : earth’s outer layer - crust, upper mantle → tectonic processes & landforms
biosphere : zone of life - ecosystems and living organisms → biodiversity, human factors
hydrosphere : water on earth - oceans, glaciers → hydrological processes, water
management
atmosphere : layer of gases → weather, climate change
interlinked by the cycles and processes
matter & energy move between the subsystems
changes that occur in one subsystem could affect the others
Water cycle
global distribution and size of major stores …
cryosphere : 69%
lithosphere : 30%
hydrosphere : 0.3%
atmosphere : 0.04%
water is continuously cycled between the different stores
the transfers…
Geography notes I 2
, condensation deposition
evaporation sublimation
melting precipitation
infiltration baseflow
drainage basins
an area of land where all the surface water drains into a common outlet
defined by natural hydrographic boundaries - ridges, hills, mountains - and vary widely
in size
rainfall is collected in streams, rivers, lakes, groundwater, etc. in the basin’s outlet
influences flow of water, sediments and nutrients across landscapes
transfers:
infiltration groundwater flow surface runoff
percolation throughflow etc…
stores:
lakes channel storage soil storage
interception absorption groundwater
water balance - how much water is stored in the basin
P = Q + E +\- S
P= precipitation Q= runoff
E= evapotranspiration S= change in storage
dry season → deficit\ shortage
recharges in next wet season
displayed on a water balance graph
hydrographs
Geography notes I 3
, show how a drainage basin responds to a period of rainfall & river discharge
used to plan for floods and drought
features include….
peak rainfall
peak
discharge
rising limb
falling limb
base flow
lag time
basins with rapid runoffs and not much storage capacity = short log time, high peak discharge
→ “flashy” hydrograph
basins with slow runoffs and high storage capacity = high log time, low peak discharge
→ “delayed” hydrograph
amount of runoff & shape of hydrograph depends on…
size of basin ground steepness
shape of basin rock & soil type
factors affecting the size of stores/flows :
human: physical:
farming practices storms & precipitation
land use/deforestation seasonal changes
water abstraction
Geography notes I 4
