Physical Geography - Water and Carbon Cycles

biogeochemical cyces

refers to cycles involving biotic and abiotic components eg the water cycle and the carbon cycle

water cycle

heat from sun - evaporation - condensation - precipitation - surface runoff - stream flow - infiltration - throughflow - percolation - groundwater flow - interception - evapotranspiration

systems are

- bounded

a generalisation of reality

have inputs, outputs, stores ad flows (about movement of matter or energy)

- are studied at a range of scales from local to global

albedo effect

lighter surfaces reflect light/ sun's energy eg snow/ice, darker surfaces absorb light/sun's energy eg concrete/water

positive feedback loop in the carbon cycle

negative feedback loop for the carbon cycle

closed system

transfer of energy in and out but not matter

dynamic equilibrium

the inputs and outputs within a system are balanced

open system

transfer of energy and matter in and out

boundary

the edge of the system (encloses the system)

flow/transfer

the movement of matter within systems

input

energy or matter going in

store/component

contains matter or energy

output

energy or matter going out

feedback

if the equilibrium of a system is upset by a change in one of the elements

positive feedback

where the effects of an action are amplified or multiplied by subsequent knock-on effects (negative outcome)

negative feedback

where the effects are of an action are nullified by its subsequent knock-on effects (positive outcome)

atmosphere

the layer of gases surrounding the planet (air)

lithosphere

solid, outer part of the Earth, includes the brittle upper portion of the mantle and the crust, the outermost layers of the Earth's structure (land)

hydrosphere

includes water that is on the surface of the planet, underground and in the air (liquid water)

biosphere

is made up of the parts of Earth where life exists. The biosphere extends from the deepest root systems of trees to the dark environment of ocean trenches, to lush rainforests and high mountain tops

cryosphere

is the frozen ice and snow on the planet (frozen water)

aquifer

a body of permeable rock which can contain or transmit groundwater

pedosphere

liquid water contained within soil, may sometimes be frozen

precipitation

transfer of water from the atmosphere to the ground

evaporation

transfer of water from liquid state to gaseous state, the vast majority occurs from the ocean to the atmosphere

evapotranspiration

evaporation combined with transpiration

condensation

transfer of water from a gaseous state to a liqquid state

sublimation

transfer from a solid state to a gaseous state and vise versa

interception

water intercepted and stored on leaves of plants

overland flow/ surface runoff

transfer of water over the land surface

infiltration

transfer of water from the ground surface into soil, wheere it may then percolate into underlying rocks

throughflow

water flowing through soil towards a river channel

percolation

water soaking into rocks

groundwater flow

transfer of water very slowly through rocks

accumulation

the addition of material to the store of ice through snowfall

ablation

the loss of material from the store of ice, occuring through melting, evaporation and sublimation

seasonal changes in the cryosphere

these occur through accumulation and ablation

glacial period

is an interval of time (thousands of years) within an ice age that is marked by colder temperatures and glacier advances. More water is stored in ice than currently.

interglacials

are periods of warmer climate between glacial periods with less ice on the plant. The last glacial period ended about 15,000 years ago. They experience a reduction in the volume of ice and the hydrological cycle behaves much like it does today

Global atmospheric circulation

Drainage basin

the area of land drained by a river and its tributaries (when it rains in this area the water finds its way into the river)

Watershed

the boundary of the drainage basin. It separates one drainage basin from another

Confluence

a point where two rivers meet

Tributary

a small river or stream that joins a larger river

Source

the starting point of a river, often a spring or lake

Mouth

the point where a river leaves its drainage basin and flows into the sea

Water balance

the balance between inputs and outputs within your system. Water balance is expressed as a % of precipitation

Surface runoff

when the ground becomes too saturated by rainwater, it can not take any more water in, any extra rain flows over ground.

Discharge

the amount of water in the river at a given time

Peak discharge

maximum discharge/amount of water in the river

Peak flow

maximum discharge in the river

rising limb

the rising water in the river

Recession/falling limb

falling flood water in the river

Baseflow

the normal amount of water you would expect in the river

Basin lag time

time difference between the peak of the rainstorm and the peak flow of the river. The shorter the lag time, the faster the flooding occurred

Peak rainfall

maximum amount of rainfall

carbon stores

lithosphere, hydrosphere, cryosphere, atmosphere and biosphere

carbon sink

a store that absorbs more carbon than it releases

carbon source

releases more carbon than it absorbs

four main carbon cycles

fast organic, slow organic, fast non-organic, slow non-organic

carbon budget

how much carbon is emitted by various processes compared to what can be absorbed by nature or captured by people.

impacts of changing carbon on oceans

ocean acidification, ocean warming, melting sea ice, ocean salinity, sea level rise

carbon capture and sequestration

a technology that can capture up to 90% of CO2 emissions produced from use of fossil fuels in electricity generation/industrial processes, preventing it entering the atmosphere

changing rural land use

when rural land is changed for another use - can improve carbon stores by, depends on land use, soil properties, climate and land area

renewable energy

energy derived from natural sources of clean energy, replenished at a higher rate than they're consumed. Generating renewable energy creates lower emissions than burning fossil fuels

geoengineering

the deliberate large-scale intervention in the Earth's natural systems to counteract climate change