water and carbon cycle

aquifer

a permeable rock layer which contains water that can be extracted for human use

jet stream

a narrow bad of fast-moving winds high up in the atmosphere

hydrological drought

when available water reserves fall below acceptable levels

agricultural drought

there is insufficient moisture for average crop production

meteorological drought

an extended period of low or absent rainfall relative to the average for a region

store

a reservoir where water is held such as the ocean or ice caps

flow

a movement or transfer between stores in a system

cryosphere

consists of those areas of the Earth where water is frozen into snow or ice, including ice sheets, ice caps, alpine glaciers, sea ice and permafrost

accumulation

is the build-up of snow and ice which takes place in the cryosphere

ablation

the change from solid ice to liquid or water vapour when temperature rises above 0°C. This wastage of surface snow or ice is achieved by melting and evaporation

arid

conditions mean a severe lack of water, usually defined as annual rainfall totalling less than 200-250mm

El Niño southern oscillation (ENSO)

a sustained sea surface temperature anomaly across the central Pacific Ocean

Earth 'snowball'

650-750 million years ago, cryosphere storage would have been much greater

open systems

allow energy and matter to be transfered across its boundary for external areas

permeability

the ease with which water can pass through rocks or a soil horizon

interception

the temporary storage of precipitation on the leaves or branches of a plant

biome

a plant community whose global distribution corresponds with a climatic region of the Earth

dividing line between drainage basins

watershed

through flow

rainwater dripping from leaves and branches towards the ground

stemflow

water that falls directly onto vegetation but flows to the ground via stems and trunks

infiltration

movement of water from the ground surface to the soil

infiltration capacity

rate at which water can pass into the soil

Throughflow

movement of water laterally through the soil, via a matrix of pore spaces, fissures and pipes

percolation

the transfer of water from the soil into the underlying bedrock

groundwater flow

the vertical and lateral movement of water through a drainage basin's underlying rock as a result of gravity and pressure

overland flow

the movement of a sheet of water across the ground surface

saturation-excess surface runoff

rainfall continues for a long time soil becomes saturated, through flow is deflected closer to the surface

infiltration-excess surface runoff

surface runoff which occurs when rainfall intensity is so great that not all water can infiltrate.

interception store

leaf and plant surfaces

vegetation store

water held in the biomass itself, also called 'green water'

surface store

water collected on the surface of the ground in expressions and hollows

soil moisture store

water held in pore spaces in the soil matrix

channel store

water held in the river channel itself at any moment in time

groundwater store

water stored in solid rock and in any superficial deposits

hygroscopic

water adhering in thin films by molecular attraction to the surface of soil particles

capillary water

water forming thicker films and occupying the smaller pore spaces in the soil

gravitational water

excess water that occupies all large and usually free-draining spaces in the soil

evaporation

the change in state of water from a liquid to a gas

transpiration

diffusion of water from vegetation into the atmosphere, involving a change from liquid to gas

channel discharge

the volume of water leaving a drainage basin via its main stream or river during a specific unit of time

antecedent conditions

the weather and soil moisture conditions immediately prior to a storm event

peak discharge

the maximum rate of flow during a storm event

peak rainfall

the maximum rainfall recorded in one of the time intervals

rising limb

the part of a storm hydrographic in which the discharge starts to rise

lag time

the time elapsed between peak rainfall and peak discharge

falling limb

the part of the storm hydrographic in which the discharge starts to falls

preceding discharge

the rate of flow prior to the latest storm event

bankfull discharge

the maximum discharge reached during a storm event prior to overtopping of the river banks and the inundation of the floodplain with excess water

baseflow

the normal minimum flow of the river

condensation

the process by which vapour changes into a liquid or solid form. For this to happen in the atmosphere, condensation nuclei must also be present

the feeder-seeder mechanism

a process that increases levels or orographic rainfall

the carbon cycle

a biogeochemical cycle which moves carbon around a global system

inorganic carbon

carbon found in the ground and not in an organism

what is calcium carbonate

it makes up skeletons, shells and calcareous rocks

carbon sink

a store of carbon that absorbs more carbon than it releases

carbon source

when more carbon leaves than enters

the pedosphere

the uppermost part of the lithosphere, the layer that chemically reacts to the atmosphere, hydrosphere and biosphere through the soil forming process

how much carbon does marine sediments and sedimentary rocks store?

100 million GtC

how much carbon does peat store?

250 GtC

hydrosphere - surface layer

where sunlight penetrates so that photosynthesis can take place; contains approximately 900 GtC

hydrosphere - intermediate layer

the deep layer of water contains approximately, 37,100 GtC

hydrosphere - living organic matter

the amount is approximately 30 GtC and dissolved organic matter is around 700GtC

how much carbon does the terrestrial biosphere store?

3000 GtC

living vegetation - store

19% of carbon in biosphere

• varies depending on location and vegetation type Russia - 25% of world's forest carbon

plant litter

Fresh, undecomposed - directly effected by type of ecosystem

• leaf tissue = 70% of litter in forest

humus

thick brown substance that remains after most organic litter has decomposed forests, tropical temperate and boreal = 31% of carbon

stores of carbon overtime

500 million years ago = 7,000ppm 2 million years ago = 190ppm now = 420ppm

Keeling curve

(average distribution of carbon-dioxide concentration)

• each year CO2 levels go up in the northern hemisphere winter due to fewer leaves - rise in levels mainly due to anthropogenic causes

photosynthesis

suns energy to CO2 6CO2 + 6H2O --> C6H12O6 + 6O2

respiration

water and CO2 are the by-products 6O2 + C6H12O6 --> 6H2O + 6O2

decomposition

happens by decomposers whose role it is to break down cells and tissues in dead organisms into biomolecules and atoms

vertical deep mixing (ocean carbon pump)

when warm waters in the ocean surface are carried from the tropics to polar regions

• water cools = more dense + sinks taking CO2 with it

combustion

organic material is burnt in the presence of O2 giving of heat, Co2 and water

Biomass combustion

burning of living and dead vegetation immediately emits 10-20% of carbon, 80% stays in dead matter

volcanic activity

minimal effects on carbon

• So2 reflects head > Co2 absorbs heat

Cement manufacturing

responsible for 5% of global CO2 emissions 900kg of CO2 produced for every 100kg of cement

bad farming practices

ploughing soil, enteric fermentation, rice paddies, deforestation, salivation, pesticides, monoculture, overgrazing, over cultivation

good farming practices

stone lines, terracing, wind-breaks, irrigation, buffer zones, crop oration, polyculture, soil conditioning, zap, afforestation, cover crops, biological pest control

anthropogenic CO2

carbon dioxide generated by human activity

biosphere

the total sum of all living matter

carbon sequestration

the capture of carbon dioxide from the atmosphere or capturing anthropogenic CO2 from large-scale stationary sources like power plants before it is released to the atmosphere. Once captured it is put into long-term storage

greenhouse gas

any gaseous compound in the atmosphere that is capable of absorbing infrared radiation, thereby trapping and holding heat in the atmosphere

weathering

the breakdown of rocks in situ by a combination of weather, plants and animals

peat - definition and formation

peat is a thick layer of black or dark brown sticky and wet material. Peat is formed from the high levels of partially decomposed vegetative matter. Decomposition is prevented by a waterlogged environment which creates oxygen-deficient anaerobic conditions. the plant remains are slowly compressed as more material is added each year

fen peatlands

where groundwater meets the surface - springs, hollows or at the edge of open water

blanket peatlands

on hilltops which receive over 1,500mm of rain a year, fed entirely by rainfall and snowmelt instead of groundwater

raised bogs

in valley bottom where soils are saturated due to frequent arrival of through flow and overland flow from the slopes above

drainage and peatlands

1/4 of England's peatland under cultivation

• large areas drained for faming --> degrading peat

pollution and peatlands

reduction in peat-forming plant species (sphagnum mosses) --> erosion of peatlands begins

burning and peatlands

burning land to encourage growth of new heather for grouse to feed on - damages wet sphagnum mosses--> exposed peat can lead to widespread and rapid erosion of pet during heavy rainfall

grazing and peatlands

1/3 UK peatlands now support invasive species - rate of formation of peat slowed = erosion

forestry and peatlands

bogs drained by forestry commissions - lose soil carbon via leaching and erosion

restoration of peatland

• re-establishment of plant cover dominated by peatland species

• re-wetting of drained peatlands

• block erosional gullies with stone dams to raise the water table

why is peat important?

• UK = 1/2 soil carbon storage globally = 3% of Earth's surface - 4 million km2

Keswick flooding

November 2015, 324mm of rain

• confined confluence with steep valley sides

• impermeable lithology

• 4 bridges destroyed and 25 closed over 6 weeks

selective logging

• only some trees are felled, canopy remains intact

• extracted by horses and helicopter

• mitigates against need for roads in the area

Peat - fenland peat

Drainage began during the roman period - drained and dried

• fenland farms supply 7% of England's agriculture - generates £3 billion a year

transport

95% of forest clearance is near to transport networks

• 80% of amazon deforestation is in the arc of deforestation

Greenland ice-sheet melting (-)

increase temp --> increase melt of ice sheet --> ice into Atlantic Ocean --> O.C.B stops (Gulf Stream) --> European ice age

Ice loss --> cryosphere (+)

temp increase --> white surfaces decrease --> increase in dark surfaces --> increase in absorption of sunlight --> temp increase