water and carbon cycle Flashcards
what are systems composed of?
- inputs (matter/energy added to system).
- outputs(matter/energy leaves system)
- stores (matter/energy builds up in a system)
- flows (matter/energy moves in system)
- boundaries (limits to the system)
what are open systems?
when system receive inputs and transfers outputs of energy or matter
what are closed systems?
energy inputs equal outputs
what is dynamic equilibrium?
inputs equal outputs despite changing conditions
what does positive feedback do?
takes away from dynamic equilibrium
what does negative feedback do?
brings back to dynamic equilibrium.
on a local scale are water and carbon cycles open or closed?
open
what system are the water and carbon cycle on a global scale?
closed
in a local drainage basin how may water get lost and gained?
- evapotranspiration/ runoff
- precipitation
what are the 3 types of rainfall?
convectional
relief
frontal
what is. convectional rainfall
warm air rise
condenses at high altitudes
falls as rain
what is relief rainfall?
warm air forced upward by barrier (mountain) causing it to condense. at higher altitudes and fall as rain
what is frontal rainfall?
warm air rises overcool air, condenses at higher altitudes and falls as rain
what is frontal rainfall?
warm air rises overcool air, condenses at higher altitudes and falls as rain
when does evapotranspiration occur?
when water is heated by the sun causing it to become a gas and rise into atmosphere.
when does transpiration occur?
in plants whiney respire through their leaves, releasing water they absorb through their roots, which then evaporates due to heating by the sun
stem flow as an output
all water that enters a drainage basin will either leave through the atmosphere, or through streams which drain the basin. may flowing tributaries.
what is infiltration?
process of water moving from above ground to soil
what is infiltration capacity?
how quickly infiltration occurs
infiltration as a flow?
grass crops/ tree roots create passages for water to flow into soil.
what is percolation?
water moves from ground or soil into porous rocks and rock fractures
what is the percolation rate dependant on?
fractures that may be present in the rock and permeability of rock
what is through flow?
water moves through soil and into streams and rivers
what is speed of flow dependant on?
type of soil soils with smaller pore
have a slower flow rate . Sandy soils drain quickly
larger pore spaces
surface run off as a flow?
water flows above ground as sheet flow or in rills
what is ground watre flow?
water moves through rocks
stemflow as a flow
- Flow of water that has been intercepted by plants or trees, down a stem, leaf, branch
or other part of a plant - Fast.
stores in the water cycle?
- soil water
- groundwater
- river channel
- interception(water intercepted by plants)
- surface storage
what is the water table?
upper level where pores and fractures in the ground become saturated
what is the water balance used for
to express the process of water storage and transfer in a drainage basin system
what is the formula for water balance?
precipitation=total runoff + evapotranspiration+/-(change in) storage
the water cycle is impacted on a local scale by? human factors
- deforestation (less interception by trees so surface run off increases)
- agriculture (pastoral farming, animals trample ground reducing infiltration)
- urbanisation (impermeable surfaces reduce infiltration but increase surface runoff reducing lag time)
the water cycle is impacted on a local; scale by? physical factors
-storm events (large rainfall saturates ground to its field capacity, no ,more infiltration, more surface run off )
-seasonal changes (spring - more vege more interception
summer-less rain more impermeable surfaces
autumn-less vege less intercep, more rainfall
winter-frozen ground impermeable, less run off due to snow )
what is the soil water budget?
annual balance between inputs and outputs in water cycle and impact on soil water availability
what is the soil water budget dependant on?
type, depth and permeability of the soil and bedrock
what is field capacity
max possible amount of storage of water in soil
seasonal variation of the soil water budget autumn?
greater input from precip than output from evapotranspiration
seasonal variation of the soil water budget winter?
evapotranspiration from plants/ trees reaches minimum precip continue to refill soil water stores
seasonal variation of the soil water budget spring?
potential evapotranspiration increase as temp increases and plants photosynthesis more
seasonal variation of the soil water budget summer ?
utilisation of soil water as evapotranspiration and rainfall minimum. output from evapotranspiration greater input from
precipitation so the soil water stores are depleting
what is the largest store of global water?
oceans (97%)
what percentage of stores are fresh water? of which? what % is ground water?
2.5% , 69% glaciers, ice caps and ice sheets and 30% ground water
surface water and other fresh water stores account t for % of global; stores
1%
what are other surface and freshwater stores?
permafrost, lakes, swamps,, marshes, rivers, living organisms
water can be stored in what 4 areas?
- hydrosphere- any
- lithosphere- crust and upper mantel
- cryosphere- any water frozen
- atmosphere- water vapor
what are aquifers?
underground water stores
how long can shallow underground aquifers store water for?
200 years
how long can deeper fossil aquifers hold water for?
10,000 yrs
how long can glaciers hold water for?
20-100 yrs
how long can lakes hold water for?
50-100 yrs
seasonal snow and rivers hold water for how long?
2-6 months
how long does soil water hold for?
1-2 months
what is the global atmospheric circulation model?
determines cloud formation and rainfall
what is ITZC
inter-tropical convergence zone
what is the low pressure Zone on the equator called?
ITZC
what is the zone partly responsible for?
monsoons due to heavy rainfall
why does this zone move?
sun position changes
what are the names of the cells that cause unstable whether in the UK?
FERREL AND HADLEY CELLS
what effect do droughts have on the water cycle over time?
cause major stores to be depleted. more common due to climate change
how often does ‘the El Nino effect’ occur? what does it cause?
2-7 yrs
warm temps
(increase due to climate change)
how often does ‘the El Nina effect’ occur? what does this cause?
2-7 yrs
cooler temps
what effect does the cyrospheric process have on the water cycle over time?
almost all of worlds glaciers are shrinking, sea level rise (if all melt rise sea levels by 60m)
what effect does water abstraction have on the water cycle?
reduces vol of water un surface stores
abstraction from aquifers as output greater than inputs= decline in global long term water stores
what is a flood hydrograph used to represent?
rainfall for the drainage basin of a river and the discharge of same river
what is discharge on flood hydrograph?
vol of water passing through cross section of river (made up of base flow and storm flow)
what does rising limb represent on flood hydrograph?
discharge increasing
what does falling limb represent on flood hydrograph?
discharge decreasing
what does lag time represent on flood hydrograph?
time between peak rainfall and peak discharge
what does base flow represent on flood hydrograph?
level of groundwater flow
what does stormflow represent on flood hydrograph?
comprised of overland flow and throughflow
what bankfull discharge mean?
maximum capacity of a river, if exceed burst and flood
what are the characteristics of a flashy hydrograph?
short lag time
high peak discharge,
high flood risk
steep rising and falling limb
what are the characteristics of a subdued hydrograph?
long lag time
gradually rising and falling limb
lower flood risk
low peak discharge
natural features that create a flashy hydrograph?
- high rainfall intensity (higher discharge potential= more likely for soil to reach its field capacity)
- high drainage density (tributaries to main river, increasing speed of drainage and decreasing lag time)
human features that would create a flashy hydrograph?
- urbanisation (impermeable surfaces, reduced infiltration)
- deforestation (water reaches ground quicker. more runoff)
what do transfers in the crabon cycle aim to do?
causes changes over time
what do transfers in the carbon cycle aim to do?
causes changes over time
when does photosynthesis occur?
when chlorophyll in leaves of plants react with co2 to create carbohydrate glucose.
what is the photosynthesis formula?
co2+h20 –> light energy –> o2+glucose
when does respiration occur?
when plants and animals convert O2 and glucose into energy produces waste of water and co2
chemical formula for respiration?
O2 + glucose –> co2 + h20
overall plants absorb more co2 than they emit what is this known as?
plants are net CO2 absorbers and net oxygen producers
what is combustion?
when fossil fuels and organic matter are burnt, emit CO2
what is decomposition?
when living organisms die and are broken down by decomposers which respire, returning CO2
by what percentage has the oceans acidity raised by? due to what?
- 30%
- diffusion
what is the biggest carbon store?
the sea
what type of weathering erodes rocks?
carbonation
when does carbonation weathering occur?
when CO2 in teh air mixes with rainwater to create carbonic acid which aids erosion
what does marine organisms use carbon for?
to build their shells
what is carbon sequestration?
storage of carbon over a prolonged period of time in a carbon store
what are the two types of storing carbon?
natural and artificial
how are factories using carbon sequestration?
in form of carbon capture and storage.
what is carbon capture and storage
CO2 is captured and transported via pipelines to depleted gas fields and saline aquifers
name 4 advantages of carbon capture and sequestration?
- can be fitted to existing coal power stations
- capture 90% of CO2 produced
- demand for CO2 means already pipelines
- potential capture half worlds CO2 emissions
name 4 disadvantages of carbon sequestration
- high cost
- increases energy demand of power stations
- may not be space to fit to old ps
- economically viable
the carbon cycle on a local scale happens in where?
a plant or sere
what is a sere?
a stage of vegetation succession
when does vegetation succession occur?
plant communities develop and become more complex over time
what is the climatic climax?
final stage of teh sere where the enviromnetal equilibrium is achieved
example of a sere?
woodland
what enviroment is the lithosere?
bare rock
what is the halosere?
salty envir
what is the hydrosere?
freshwater
what is a carbon sink? example?
any store which takes in more carbon than it emits
INTACT tropical rainforest
what is carbon source? example
any store that emits more carbon than it stores
DAMAGED tropical rainforest
name two things carbon emissions have come from 1750-2012
coal (673 Gt)
oil (496 Gt)
name 3 places are carbon has gone to?
atmosphere (879)
ocean (590)
land (528)
name three main carbon stores?
- sedimentary rock (lithosphere) - 66,000-100,00 million billion metric tones of carbon
ean
name three main carbon stores?
- sedimentary rock (lithosphere) - 66,000-100,00 million billion metric tones of carbon
ean
what forests have seen an n increase in carbon sequestration in recent years? due to?
NON TROPICAL FORESTS
due to conversion of agricultural land and plantations to new forests.
Rate of forest loss has decreased from what 1990 to what 2010/5?
- 5 million hectares
5. 5 million hectares
what country has the most carbon stored on land and the most extensive deforested area
BRAZIL
what country has the largest amount of afforested area.
CHINA
what does NNP stand for and what does it mean?
Net Primary Productivity
refers to amount of carbon absorbed by forests
what 2 natural processes cause changes over time in carbon cycle?
- wildfires
- volcanic activity
how do wildfires affect the carbon cycle?
- transfer carbon form biosphere to atmosphere, burning can encourage the growth of plants long term
how does volcanic activity affect the carbon cycle?
carbon stored in earth is released during eruptions, contribute a relatively low proportion of CO2, lower photosynthesis rates
name 4 human impacts of carbon cycle?
- fossil fuel use
- deforestation
- changes in magnitude of carbon stores
- carbon budget
name 3 human impacts of carbon cycle?
- fossil fuel use
- deforestation
- changes in magnitude of carbon stores
how does the use of fossil fuels affected the carbon cycle?
- combustion transfers CO2 from a long term carbon sink
how does deforestation affect the carbon cycle?
- often used to clear land for housing, rapidly releases carbon stored in plants using slash and burn techniques
how does human activity affect changes to the magnitude of carbon stores over time therefore carbon cycle?
- human activity causes unprecedented flux in levels of CO2 result of fossil fuel combustion
what is the enhanced green house effect?
process that is currently causing global warming as abnormally high levels of greenhouse gases being produced by humans, trapping radiation form sun
what is the difference between the greenhouse effect and the enhanced greenhouse effect?
enhanced greenhouse effect is caused by humans the greenhouse effect is a natural process
what does radiating forces refer to?
difference between incoming solar radiation absorbed by earth and energy radiated back out into space
what is the most important anthropogenic greenhouse gas? what percentage to radiative forcing?
CO2
increase in global temp due to alteration of carbon cycle will have significant impacts on what cycle?
water cycle- increases evapotranspiration
what impact does increase in global climate have on seasons?
summer storms more likely
decrease rainfall in summer
increase winter rainfall
name 4 causes of the enhanced greenhouse effect?
- land use change- 1/10 carbon release (farming 70% deforestation in amazon due to cattle ranching)
- fertilisers (rice padi fields)
- deforestation (deforestation20% of all global greenhouse emissions, reduces carbon sequestration and land becomes a carbon source rather sink)
- urbanisation 97% of all human caused CO2. cement 7% og global CO2 emissions
what does the Vostok ice core data from Antarctica suggest?
that in the past temperature change has occurred before CO2 levels have risen
what was the explanation they had for global warming?
variations of the earths orbit cause periods of time where we experience a greater heating effect from the sun. this causes glaciers to melt and increases flow of carbon cycle.
what is there theory an example of? feedback
POSITIVE, quantity of fresh water flowing into oceans increase, temp fluctuations between earths two hemispheres. as oceans become warmer they release more CO2 . temp rise
over what % of warming is cause by a rise in atmospheric CO2
90%
what is an issue with this ice data conculation?
the results are not widely agreed on, any systematic error would affect the overall conclusions of the study
what do 97% of climate scientists agree on?
GW over the last 100 yrs is v likely to be due to human activity
who are the IPCC and what do they say?
International Panel on Climate Change, say its virtually certain that humans are to blame for ‘unequivocal’ global warming
what impact does the carbon cycle have on tropical rainforests?
- high rates of photosynthesis and respiration leads to greater humidity, cloud cover and precipitation.
- deforestation reduces photosynthesis and respiration, further reducing humidity and cloud cover and decreasing precipitation
what impact does climate change have on oceans?
- warmer oceans cause more plankton growth and through plankton chemical production, cause clouds to potentially form
- warm oceans store less CO2, as carbon sequestration is dependant on cooler oceans. means higher temps could lessen effects of oceans as Carbon sink. WARMWE oceans are classed as CO2 sources= POSITIVE FEEDBACK
what is a feedback loop?
type of chain reaction, where one process leads to another process, leading to another, so on =.
what is negative feedback?
- process that occus is counteracted by an opposing process, causeing the effects to chanel eachother out and nothing to change
what is positive feedback?
a process occurs, which causes another process to occur, which starts a chain reaction that heightens the first process
name three positive feedback loops of the Carbon cycle?
- wildfires (hot dry climate, created by global warming- releases large CO2- increases warming effect)
- Ice reflects radiation from sun reducing surface warming. sea temp rise, ice melts, warming is amplified as no ice to reflect radiation
- high temp= thawing permafrost releasing CO2 & METHANE permafrost= frozen ground stays at 0 degrees for 2 yrs.
name 3 negative feedback loops of the carbon cycle?
- increased photosynthesis by plant and rising temp allows vege to grow in new areas (melted permafrost areas) new vege absorbs CO2 decreasing warming effect
- high temp and more CO2 cause a greater carbon fertilisation in plants, absorbs more CO2. reduces CO2 in atmos rates of warming and carbon fertilisation decrease
- higher CO2 plankton to grow (feed of co2). CO2 taken in through photosynthesis and levels decrease= plankton decrease
what is a moorland (peatland)?
expense of waterlogged, acidic soil and peat (decayed organic matter).
what does waterlogged ground do to reduce plant growth?
stops oxygen
what are moorlands a major store of ?
CO2 (biggest terrestrial carbon store)
many moorlands have been drained of large channels which means?
no longer submerges
what are moorlands often converted into?
highly productive farmland or plantations in tropical areas due to fertile soils. incraeses flood risk
what has this caused?
increases flood risk as surface storage is reduced by draining morrland and streamflow in sincreasd by digging grainage ditches.
what is the impact on the carbon cycle after turning moorland into farmland?
- moorland drained
- water table is lowered affect flows in water cycle
- dry peat degrades easily
what is the natural rainforest water cycle?
- precipitation cycle
- 75% intercepted by trees.
- 35% stem flow reaches ground, infiltrates soil (35% used by plants, transpiration)
- 25% evaporates
what is teh deforested rainforest water cycle?
- precipitation occurs
- most reaches ground immediately, high surface run off, increasing flood risk
- less evaporation, so atmosphere less humid and less rainfall
what is the natural rainforest carbon cycle?
- trees suited to humid conditions , promotes photosynthesis
- absorb large amounts of O2, CARBON SINK
- decomposition and respiration releases CO2 back into atmosphere and soil, where carbon stored
what is the deforested rainforest carbon cycle
- lack of trees so photosynthesis reduced
- fires to clear land leads CO2 released into atmosphere. forests carbon SOURCE not sink
- lack of life
- low rates of decomp
rain thar forms ovre intact tropical rainforests may fall over deforested land, causing soil erosion, what can then happen?
if soil and ash flows into rivers increases carbon contents of rivers.
how does water leave the rainforest cycle?
output through streamflow due to reduced interception and increased surface runoff
Alternatively there is reduced rainfall in the intact forest as?
less evapotranspiration on deforested areas
what does this cause?
drought periods and the intact rainforest to deteriorate
what does deforestation on peatland and teh digging of drainage channels reduce?
water storage
the organic peat matter is no longer preserves underwater what happens?,m
decomposes quickly, releasing co2 into atmosphere
what increases decomposition in rainforest cycle?
weathering and erosion increase
blocking drainage ditches in peatlands rainforests helps restore natural environment how?
increasing soil water storage and decreasing runoff, raises water table and decrease flood risk
rises in the water table ensure what?
steady water supply, better quality as filtered in wetlands
why is carbon storage increased?
peat is made up of crabon and water.
how can mitigation help climate change
- setting targets to reduce greenhouse gases
- switching to renewable sources of energy
- carbon capture or carbon sequestration
global intervention- Paris climate agreement?
- aim to limit increase of global temp by 2 degrees above pre industrial levels
- support developing countries
- meet every 5 years to review goal
regional intervention- EU 20-20-20?
- 20% reduction in GHG and commitment to 20% of energy coming from renewable sources and 20% increase in energy efficiency by 2020
- increase its emissons reduction to 30%
national intervention- climate change act 2008 UK
legally binding target for UK reduce GHG emissions by 80% of 1990 levels by 2050, target of 26% by 2020 increased to 34%
local scale
- improve home insulation
- recycling
- smart meters
regional intervention- EU 20-20-20?
- 20% reduction in GHG and commitment to 20% of energy coming from renewable sources and 20% increase in energy efficiency by 2020
- increase its emissions reduction to 30%
