the carbon cycle
Albedo flip
When the sunlight reflected by white ice is suddenly absorbed as ice melts, creating a dark surface of open water.
Major players in the world of energy: transnational companies
nearly half of the big oil companies are state owned and are under government control. strictly speaking this means thery are not TNCs
what would happen if there was changes in the system?
negative or positive feedback
chemical weathering
the geological part of the carbon cycle interacts with the rock cycle, a series of contstant processes through when Earths materials change from one form to another over millennia.
Thermohaline circulation
the global system of surface and deep water ocean currents is driven by temperature (thermo) and salinity (haline) differences between areas of oceans.
implications for ecosystens
valued for the services they provide for the planet by regulating carbon and hydrological cycke -global warming and its impacts may change biodiversity -marine organisms threatened with lower oxygen levels, high rates of ocean acidification, rising temperatures, alter food chain (plankton)
highest to lowest rates of NPP
1. estuaries 2. swamps 3. tropical rainforests 4. temperate forests
ITCZ (intertropical convergence zone)
A concentration of warm air that produces rainfall as part of a global circulation system -small shifts in its location can cause drought
Loss of Arctic albedo
Albedo is a measure of how sunlight is reflected awau from the earths surface -ice has a high reflectivity index, reduction in the amount of sea ice may create feedback loop -melting allows more heat absorbtion -loss of reflective albedo: less summer sea ice replacement of lighter tundra with darker fprests Black carbon (soot) pollution on snow adds to heat absorption and melting
land conversion
Any change from natural ecosystems to an alternative use; it usually reduces carbon and water stores and soil health.
Water conservation and management
Benefits- less resources used, less groundwater abrstraction, use more grey water (recycled) costs- efficiency and conservation cannot match increasing demands for water -needs smart meters
Carbon cycle
Biogeochemical cycle by which carbon moves from one sphere to another. it acts as a closed system made up of linked subsystems that have inputs, throughputs and outputs. carbon stores function as sources (adding carbon to the atmosphere) and sinks (removing carbon from the atmosphere)
unconvential fossil fuels
Canadian tar sands: exploiting the canadian deposits on a commercial scale started 1967 and has focused on the province of alberta. produce 40% of canadas oil output. 2015 fall in the global price of oil had an impact on the tar. Extracting bitumen is relatively expensive, high energy iput. Scale of strip mining requires the clearance of large areas of taiga.
Carbon Co2 feedbacks
Carbon emissions will outpace uptake as warming continues: -increased CO2 emmisions from tundra soils -forest growth will absorb mre of the suns energy, acclerates climate change -methane hydrates are found in permafrost and ocean sediments in shallow water. store more carbon than all of the proven reserves of coal, oil and natural gas Destabilise after thawing and add to greenhouse gases
Carbon fluxes vary:
Dirunally- during the day the fluxes are positive from the atmosphere to the ecosytems, at night the flux is negative, loss from the ecosystem to the atmosphere Seasonally- in the northern hemisphere winter, few land plants are griwubgm atmospheric CO2 concentrations aruse,
Short-term energy security:
Focuses on the ability of the energy system to react promptly to sudden changes in the balance between energy demand and energy supply
Carbon fossil fuels
Made up to 300 milion years ago from the remains of organic material. -organisms (once dead) sink to the bottom of rivers, covered by mud and decay anaerobically (without oxygen) -deeper the deposit = the more heat and pressure exerted on the depositis
how much do fossil fuels account for in the global energy mix:
Over 80%
Processes that drive the flows or fluxes between the stores:
Photosynthesis and diffusion
climate forcing
Predictions are uncertain because changes to the climate have several causes and feedback mechanisms
why is a balanced carbon cycle important
Regulate earth's global temperature/climate by controlling the amount of CO2 in the atmosphere. -Ecosystems and agriculture depend on the carbon cycle
measuring how efficentally energy is being used, energy intensity:
a measure of how efficiently a country is using its energy. -Calculated as units of energy used per unit of gross domestic porduct -high energy intensity indicates a high price or cost of converting energy into GDP -recognnised that energy intensity decreases with economic development: energy is used mor efficiently and the cost per unit becomes less
climate change adaptation
actions taken to help communities and ecosystems cope with changing climate condition
humus
after deaths there are 1000s of compounds in the soil to be decomposed most long-term process is the formation of humus/ seen easily in spils as it has a dark, rich colour Humus soils are 60% carbon and are important for sequestration as well as for water storage
climate
another factor affecting energy consumption -Very high levels of consumption in north america, the middle east and australia reflect the extra energy required to make the extremes of heat and cold more comfortable, not only in the home but also at work and in public places -low energy consumption in agrica due to its heat
two biomes most at risk
arctic and coral ecosystems
terrestrial ecosystems
carbon dioxide is taken from the atmosphere by plant photosynthesis, carbon is sotred organically in trees. rapid interchange with atmosphere over seconds
what does organic matter decompositioning result in?
carbon returns to inorganic forms such as carbon dioxide and carbonates contained in rock and seawater
carbon captue and storage
coal will never stop being part of global energy budget (cheap) -wide global distribution, locally sourced -CCS involves capturing the carbon dioxide released by burning of fossil fuels and burying it underground -promises the greatest savings in emissions where coal is being used to generate electricity 'scrubs'- takes some of the carbon dioxide out of natural gas used widely -it is expensive because of complex technology -no one can be sure that the CO2 will stay underground and that it will not leak into the atmosphere
Energy companird
companies that convert primary energy into electricity and then distribute it. most companies are involved in the distribution of both gas and electricity. they have considerable influence when it comes to setting consumer prices
solar radiation management
counteract global warming -use orbiting satelittes to reflect some inward radiation back to space could cool the earth and less expensive than mitigation costs: untried -would reduce but not elimate the worst effects
long- term energy security:
deals with timely investments to supply energy in line with economic developments and environmental needs
soil health
depends on the amount of organic carbon stored in the soil -depends on its inputs (plant/animal residues and nutrients) -and outputs (decomposition, erosion) -carbon is the main component of soil organic matter and helps give soil its water-retention capacity, structure and fertility -organic carbon is concentrated in the surface soil layer as easily eroded small particles so soil erosion is a major threat to carbon storage and soil health
Energy mix
every countries satisfies its energy needs in a particular way, referred to as its energy mix.
what does the biogeochemical carbon cycle?
every microbe, leaf, puddle, grain of rock, dead being and volcanic eruption,
Oceanic
exchanges are rapid with the atmosphere: -physical processes -biological processes -some of this carbon sinks to the deeper ocean pool
methods of mitigation in uk: carbon capture and storage
few CCS projects exist globally, despite its potential. Canadas boundary dam is only large scale working shceme -2015, uk govt cancelled its investment
Kyoto protocol
first major international effort to encourage both long and short term climate change was 1997 kyoto protcol an agreement to cut GHG emissions by 5% on 1990 levels by 2012.
purpose of the carbon cycle pumps
flux surface ocean CO2 to the deep ocean
Deforestation
forests take 30% of earths land area -absorb rainfall and increase groundwater storage -increasing demand for commodity production 50% of all current deforestation is for soy, palm oil, beef and paper other csauses: dams, infrasctructure and mining by 2015- 39% of all global forest cover had been completely cleared, 20% degrated 13 million hecctares are defrosted annually
brazilian deepwater oil
huge oil deposits off the brazilian coast in 20016 -one of leading emerging economies and needs oil and gas -by 2020, petrobras wants to raise production to 500,000 barrels of oil a gay since 2006- coast has been disfigured by refineries and the bases that serbe the oil and gas fields -serious pollution of coastal waters -risky nature of drilling so far offshore -rough seas -oil and gas resevoirs contain huge amounts of toxic, flammable and explosive gases
how does carbon move from one sphere to another?
known as the biogeochemical carbon cycle.
Soft strategies
legislation, land-use zoning
carbon storage times: oceanic
most carbon is dissolved inorganic carbon stored at great depths, very slowly cycled (38,000PgC)
consumers
most influential consumers are transport, industry and domestic users. -largely passive players when it comes to fixing energy prices
what regulates the geological carbon cycle?
negative feedback
carbon in limestone and shale
one of the earth's largest carbon stores is the himalayas, which started off as oceanic sediments rich in calcium carbonate. -Carbon is being weathered, eroded and transported back to the oceans -oceans today- 80% of carbon- containing rock is from shell building organisms and planton -precipitated on to the ocean floor, form layers, cemented together and lithified into limestone -remaining 20% of rocks contain organic carbon from organisms that have been embedded into layers of mud -millions of years, heat and pressure compress the mud and carbon to form sedimentary rock (shale)
Volcanic outgassing
pockets of CO2 in earths crust. -disturbance by volcanic eruptions and earthquake activity may allow pulses into the atmosphere
anthropogenic
processes and actions associated with human activity
energy security
refers to the uninterrupted avaliability of energy sources at an affordable prices
Carbonate pump
relies on inorganic carbon sedimentation -Marine organisms use calcium carbonate to make hard outer shells (plankton, coral, oysers, lobsters) These organisms die and sink, shells dissolve before reaching the sea flor. Carbon becomes part of deep ocean currents. Shells build up on sea floor, form limestone sediments
hard strategies
require technoogy (wind farms)
carbon storage times: crustal geological
sedimentary rocks, very slow cycling over millennia (100,000,000 PgC) fossil fuels store an extra 4000
the geological carbon cycle
slow part of the cycle is centred on the huge carbon stores in rocks and sediments -resevoir turnover rates of at least 100,000 years -organic matter that is buried in deep sediments takes millions of years to turn into fossil fuels -Carbon is exhanged with the fast componant through volcanic emissions of carbon dioxide, chemical weathering
land use planning
soft management: land-use zoning, building restrictions in vulnerable flood plains and low-lying coasts enforcing strict run off controls and soakways costs:public -megacities, unable to happen -needs strong governance and compensation
Biological carbon
soils store 20-30% of global carbon, store about 2x the quantity of carbon as the atmosphere and 3x that of vegetation. Two sources of carbon in soils. Arid and semi-arid soils. Most important store is from organic sources through photosyntheisis and decomposition. living organisms represent about 5% of the total soil organic matter all part of plant is made of carbon, any loss to the ground means a transfer from the plant to the soil. -carbon is stored as dead organic matter in soils for years, decades or even centuries in colder climates, being broken down by soil microbes and released back to the atmosphere
Methods of mitigation to UK: Afforestation
tree planting in UK has increased, helping carbon sequestration forestry commission, charities such as national trist and woodland trust, landowners and local authorites Big tree plant campaign encourages 1 million new tress
what are the most productive biomes
tropical forests, savannahs and grassland, account for half of global NPP. storage is mainly in plants and pcoa;s Largest store is in trees, can live thousands of years
US shale gas
2000, shale gas provided 1% of the USA's gas supply. 2015 it was nearly 25% -due to the growing use of fracking to release oil and gas from undergound formations =most important shale gas field in new york, pennsylvania, texas, west virginia -fracking for oil in the USA is now a key determinant of US oil secuirty, increasing influence on global oil price -environmental concerns: possible contamination of groundwater by chemicals in pumping fluis -known to produce airborne pollutants such as methane,benzene and sulphur dioxide
afforestation
2014- New York declaration on forests set a global target to restore 350 million hectares of deforested and degraded forest by 2030 -benefical for CO2 sequestation Chinas three-north shelterbelt project (4500km green wall of trees designed to reduce desertification
atmosphere store
589 + 240 (anthropogenic/human) PgC
ocean acidification
Oceans are an important carbon sink -changes their overall pH, acidifying then -ecosystems are being effected (coral) Past 300 million years- average oceanic pH was 8.2, dropping to 8.1 by 2015 -since industrial revolution, pH has decreased by 0.1 (30% drop) -ecosystems of coral stop growing if under 7.8 Acidifciation increases the risk of marine ecosystems reaching a critical threshold of permenant damage -ocean acidification impacts amplified by warmer temps, cyclones and pollution if ocean acidification is slow enough- organisms may able to adapt and be more resilient Arctic ocean likely to be first affected due to low pH -acidification affects shell building marine organisms becuse carbonic acid reacts with carbonate ions in the water -results in thinner shells -dissolves carbonate shells -reef building may collapse
Fluxes
Movements of organic compounds through an ecosystem
Governments
guardians of national energy secuirty and can influence the sourcing of energy for geopolitical reasons
carbon cycle: last few centuries
had been fairly constant over the last few centuries, although erosion and river fluxes have been modified by changes in land use
technology
modern technology can help in the exploitation of energy resources that are not so readily accessible -deposits of oil and gas require deep drillingthrough a contorted geology -technology can help tap energy resources that are not so readily accessible, likely to encourage energy consumption
Geological origins
most of the earths carbon is geological, resulting from the formation of sedimentary carbonate rocks in the oceans, biologically derived carbon in rocks like shale and coal -slow geological processes release carbon into the atmosphere through chemical weathering of rocks
The Intergovernmental Panel on Climate Change (IPCC) suggests:
-increased fluxes to biological store -increased soil storage in high latitudes, only limited by nitrogen abaliability -loss of storage in unfreezing permafrost and in the southern ocean and north atlantic because of warming
The earths climate is driven by inccoming shortwave solar radiation:
-Approximately 31% is reflected by clouds, aerosols and gases in the atmosphere and by the land surface -The remaining 69% is absorbed; almost 50% is absorbed at the Earth's surface, especially by oceans -69% of this surface absorption is re-radiated to space as longwave radiation -a large proportion of this longwave radiation enutted by the surface is re-radiated back to the surface by clouds and greenhouse -the trapping of longwave radiation in the atmosphere is what gives a life-supporting average of 15 degress
long term stores
-Crustal/terrestial geological -oceanic (deep_
how will climate zones shift?
-Northern middle and high latitudes will undergo more changes than the tropics -in the tropics, mountaineous regions experience bigger changers than low altitiude areas -coldest climate zones will largely reduce in size while dry regions will increase -cool summers will change to hot summers in many places
Negatives for renewables
-Very few countries where renewables might completely replace all the energy derived from fossil fuels -renewables have higher costs -significant impacts on the environment -NIMBYISM, protests on wind farms
where does volcanic outgassing occur
-active or passive volcanic zones associated with tectonic plate boundaries, including subduction zones -places with no current volcanic activity, such as hot springs in Yellowstone nationak park, USA -direct emissions from fractures in the Earth's crust
Following fact file shows the importance of oceanic "health":
-all countries eat and sell fish or shellfish -FAO estimates that fishing supports 500 million people, 90% of whom are in developing countries -fish is cultural choice in wealthier countries such as Iceland and Japan -essential for poorer countries such as Namibia, Ghana and Senegal -fish provides 16% of annual protein consumption for 3 billion people -million's of small scale fishing families depend on seafood for income. 6% of GDP is from fish and it provides essential proteins -countries depend on exports of fish stocks such as China and Thailand -many nations rely on tourism associated with coral reefs. Maldives attractcs 1 million tourists annually -coral reefs help protect areas, 200 million -Marine conservation zones
a high dependence on imported energy puts a country at risk from sudden threats, for example:
-artificial and abrupt hikes in energy prices -supplies cut off by military campaigns or civil unrest
fossil fuel combustion
-been burnt faster since industrial revolution -primary energy source -without human interference, the carbon in fossil fuels would flux very slowly into the atmosphere through volcanic activity. -fossil fuel combustion shifts this flux from slow to fast carbon cycling. 50% of extra emissions of CO2 since 1750 have remained in the atmosphere, rest has been fluxed from atmosphere into oceans, ecosystems and soils
mitigation methods in UK: Carbon taxation
-carbon price floor tax sets miniumum price companies have to pay to emit CO2. unpopular with industry and environmental groups. 2015- policy frozen lower road taxes for low carbon emitting cars scrapped in 2015 -in 2015 oil and gas exploration tax relief was expnded to support fossil fuels
geological processes
-carbon takes 100-200 million years to move between rocks, soil, ocean and atmosphere. slower carbon cycle faster carbon cycles of ecosystems and anthropogennic cycles
the capacity of soil to store organic carbon is determined by:
-climate: dictates plant growth and mircobial activity. Rapid decomposition occurs at higher temperatures or under waterlogged condition. Places with high rainfall have increased potential carbon storage. Arid soils store 80 tonnes per hectare compared with 800 tonnes per hectare in colder regions -Soil type: Clay rich soils have a higher carbon content than sandy soils. Clay protects carbon from decomposition -Management and use of soils: Since 1850, soils gradually lost 40-90 billion tonnes Gt of carbon through cultivation and disturbance. Current rates of carbon loss due to land- use change are 1.6 + 0.8 billion tonnes og carbon per year
human factors on carbon
-economic growh, population,growth, energy sources. 2014- the 3 largest CO2 emitters where china , usa and india. 2000- china overtook USA because of global shift in manufacturing reflects level of development.
carbon cycle before the industrial revolution:
-fast carbon cycling is thought to have been relatively balanced before the industrial revolution, which started in the 18th century. it functioned in a steadystate system
oil and natural gas formation
-formed from remains of tiny aquatic animals and plants -gas and oil occur in pockets in rocks -natural gas (methane) is made up of fractions of oil molecules, so small they are in gas form
two main components of the carbon cycle
-geological carbon cycle -biological/physical carbon cycle
cost
-includes a number of seperate costs: -physical exploitation -processing (converting a primary into a secondary resource) -delivery to the consumer -relatively low energy costs may be expected to boost energy consumption
implications for the hydrological cycle
-increase evaporation rates, more moisture throughout the cycle than stored in oceans, intense precipitation events -change precipitation type, earlier peaks in snowmelt and resulting river flows into oceanic stores -increase surface permafrost temperatures -reduce sea ice, ice cap and glacier storage -change the capacity of terrestrial ecosystems to sequester carbon and store water; an example of the importance of water storage is in the Amazon, 60% of precipitation orginiates from evapotranspiration El-nino is important factor in earths clima. droughts and flooda may be more intense and increase in frequency
Negative feedback: volcanoes
-increase in volcanic activity -rise in CO2 emissions and loss of carbon from rocks -temperature rises -more uplift of air, condensation -more chemical weathering and erosion of rocks -more ions deposited on ocean floors -more carbon stored in rocks -increase in volcanic activity
key processes in the geological carbon cycle
-mechanical, chemical, biological weathering of rocks on land in situ -decomposition -transportation -sedimentation -metamorphosis
Physical availability
-most fundamental of all the factors -avaliable within the country? -have to be imported? if energy is imported, then transport costs are likely to add to the overall cost of energy to the consumer. rising costa are likely to be a downward pressure on energy consumption
sources of the energy mix:
-non-renewable fossil or carbon fuels (oil, natural gas and coal) -recyclable fuels (nuclear energy, general waste, biomass) -many types of renewable energy (wind, geothermal, water and solar)
biological processes sequestering carbon: ocean sequestration
-oceans are the earth's largest carbon store, 50x greater than the atmosphere - 93% of CO2 is stored in algae, plants and coral -small changes in oceanic carbon cycle can have significant global impacts gas exchange flux between oceans and atmosphere operates on a timescale of several hundered years significant input of both organic carbon and carbonate ions from continental river run-off only a small proportion of this carbon is buried in ocean sediments important long-term carbon stores with fluxes
how is energy security vital to the functioning of a countrtL
-powers most forms of transport -lights up settlements -warms or cools our homes -modern communication 0nanufacturing
biofuels
-recently come into prominence -commercial use of relatively new biofuels -growing of biofuel crops to decrease consumption of fossil fuels (wheat, maize,grasses, soy beans) UK- two main crops are oilseed rape and sugar beet, converted into ethanol or biodiesal for vehicles -hectares of space needed to grow energy crops
Impact Deforestation on Carbon Cycle
-reduction in storage in soil and biomass -reduction of CO2 intake through photosynthesis flux -increased carbon influx to atmosphere by burning and decomposing vegetation
russian gas to europe
-russia is the worlds 2nd largest producer of gas -imports significant amount of gas to meet its own needs -most of gas exports go to europe via network of popelines -3 of those pipelines cross ukraine, russia has had recent military action there, annexing crimea in 2014. -Ukraine is in a position to make life difficult for the russian gas industry, could threaten to increase the price, or could stop the flow altogetther. russian anxiety about pipelines in Ukraine- ukraine might join EU and become member of NATO russia has two basic options: -substantially reduce or stop the delivery of gas across ukraine by exporting most of the gas through the two norther pipelines -annexe the ukraine -giving serious consideration to annex ukraine -strained historic relations between russia and westerm europe -eu do not want to increase reliance on russian gas. UK gets most of its gas from Qatar, 2015 it agreed to double its imports of russian gas to 29.1 billion cubic metres a year by 2021.
issues related to nuclear power:
-safety, incidents at Chernobyl, Fukushima -security if nuclear powered stations in an era of international terrorism -disposal of highly toxic radioactive waste with an incredible long decay life -technology involved which effectively means that the nuclear option is only open to the most developed countries -costs, costs of building and decommissioning are high
unconvential fossil fuels costs
-still fossil fuels, their exploitation and use continue to threaten the carbon cycle and contribute to global warming -extraction is costly and requires a high input of complex technology, energy and water -threatens environmental damage and risk
regional trends of deforestation:
-temeperate forests such as UK and USA have long history of exploitation: 90% was deforestated by 19th century -Boreal forests have been increasingly threatened by mid-twentieth century, by oil and tar sands production in russia and china -tropical forests have lost 50% since 1960s -Indonesia has overtaken brazil in rate of deforesation, palm oil production and logging
Short term stores
-terrestrial soil -oceanic -atmospheric -terrestrial ecosystems
carbon is present in the stores of:
-the atmosphere (carbon dioxide and methane) -Hydrosphere (dissolved carbon dioxide) -the lithosphere (carbonates in limestone and fossil fuels such as coal) -Biosphere (living and dead organisms)
UK energy mix
-very mindful of the need to become energy secure and reduce carbon emissions -shift from direct use of coal, has reliance on oil and natural gas (80% of UK's primary energy) -Petroleum for transport -gas for electricity -unlikely to change in near future --contribution by renewables is disappointingly small -consume less energy than in 1970 despite a population increase of 6.5 million. -UK is now more efficient -households use 12% less -industry uses 60% less -big increase of vehicles on the road and the flights
how much co2 do volcanoes currently emit
0.15-026 Gt CO2 annually
processes of chemical weathering:
1. in the atmosphere, water reacts with atmospheric CO2 and carbonic acid forms. reaches the surface as rain, reacts with some surface minerals 2. Transportation of calcium ions by rivers from the land into oceans. Combine with bicarbonate ions to form calcium carbonate and precipitate out as minerals such as Calcite 3. Desposition and burial turns the calcite sediment into limestone 4. subduction of the sea floor under continental margins by tectonic spreading 5. some of this carbon rises back up to the surface within heated magma, is 'degassed' as CO2 and returned to the atmosphere -dimonds, purest form of carbon, have been found 700km deep, proving that carbon is cycled betweens earths surface and lower mantle.
how much does the terrestrial biosphere sequest?
1/4 of fossil fuel CO2 eissions annnually, lows down clobal warming -growing demands have led to land conversion
OPEC
12 member countries and between them owns about 2/3 of the worlds oil reserves. It is in a position to control the amount of oil and gas entering the global market, as well as the prices. -accused of holding back production in order to drive up oil and gas prices
How much % of natural primary forests?
15%
example of a major degrassing
1991 eruption of Mt Pinatubo in the Phillippines, part of an island arc created by subduction zones. -return CO2 to atmosphere, fresh silicate rock erupted starts the cycle again
How much area do forests take of land areA?
30%
How much CO2 do humans emit
35 Gt
how many of surface volcanoes are currently active
70%
Amazons changing climate
Forests acts as a global regulator -pumps 20 billion metric tonnes of water into the atmosphere daily -humidity lowers atmospheric pressure, allowing moisture from the atlantic ocean to reach further inland since 1990, more extreme cycle of drough and flood wetter rainy season due to shift in inter-tropical convergence zone -rainfall has decreased downwind of deforested areas -droughts degreaded much of rainforest
Impacts of rising temperatures
Global warming is increasing temperatures globally Warmer air affects evaporation and stores more water, amount of water in atmosphere will increase -rain dropping during individual storms increases Over last 20 years antarctic and greenland ice sheets have been losing mass, glaciers shrinking, spring snow cover decrease Arctic is early warning system for the rest of the planet Arctic temperatures have risen twice as fast as global averages: 3/4 degrees in alaska -huge implications for ocean currents, air circulation and sea level rise -arctic stores far more carbon than any other region -4-5% of total oceanic stores, more vulnerable to global warming with further ice loss, increases in marine plants like phytoplankton limits net increase of uptake of CO2 -high risk of irreversible feedback
methods of mitigation in uk: energy effeciency
Green deal scheme encouraged energy saving improvements to homes, boilers, lighting and insulation. scrapped in 2015 energy suppliers must comply with energy company obligation scheme
hydrogen fuel cells
Hydrogen does not occur naturally on earth, combined with other elements -extracted from other forms of fuel -high in energy, pure hydrogen produces almost no pollution -Since 1970s- NASA has used liquid hydrogen to propel space shuttles and other rockets -hydrogen fuel cells have powered shuttles electrical systems Fuel cell combines hydroegen and oxygen- produces electricity, heat and water PROMISING: -Source of heat and electricity for buildings -Power source for electric vehicles
implications for the climate
Impacts of fossil fuel combustion on climate are at global and regional scales -2014 IPCC report linked greenhouse gases to fossil fuel emissions, rising global temperatures and sea levels -global warming could affect the thermohaline current by slowing or reversing the north atlantic drift (gulf stream)
flood-risk management
Localised flood defences, rivre redging, permeable tarmac reduced deforestation and more afforestation upstream absorb water and reduce flood risk downstream Costs: debate about funding sources Land owners may demand compensation -constant management is needed in hard management Techno-centric fixes= disbelief that technology cannot overcome natural processes
What does NPP stand for?
Net primary production (of carbon)
highest productivity occurs:
On land: in areas that are warm and wet. the amount of water avaliable limits primary production, for example, deserts and dry shrub lands have little biomass above ground. forests store the largest amount of carbon collectively. tundra has the least spatial extent but has the highest density of carbon storage in its permafrost In Oceans: shallower water, allows higher photosyntehtis, recieve higher nutrient inputs
methods of mitigation in UK:renewable switchinG
Renewables offer intermittent electricity, whole fossil fuels provide continuous power essential for infrastructure the climate change levy formed in 2001 to encourage renewable energy was scrapped in 2015
evidence from the ice cores:
Shows relatively small variations of atmospheric CO2 until the late nineteenth century, despite small emissions over the last millennia from land-use changes caused by human activity
Photosynthesis and the atmosphere
The atmosphere is stratified into a number of different layers. -greenhouses gases absorb radiation from the sun and maintain temperature of the earth -photosynthetic organisms play an essential role in helping tio keep CO2 levels relatively constant (help to regulate earths average temperature). -distinct spatial patterns in plant productivity and carbon density
Renewable and recyclable energy
The main forms of renewable energy being harnessed are hydro,wind,solar, geothermal and tidal. -not all countries have renewable nergies to exploit -not all countries have coasts, 'hot rocks', warm climates, permenantly flowing rivers, persistantly strong winds.
sequestering
The natural storage of carbon by physical or biological processes such as photosynthesis
Carbon Cycle pumps
The processes operating in oceans to circulate and store carbon biological pump carbonate pump physical pumps
energy pathway
The route taken by any form of energy from its source to its point of consumption. The routes involve different forms of transport, such as tanker ships, pipelines and electricity transmission grids.
climate change
Triggers enhanced greenhouse 2015- first year to exceed the key benchmark for global warming of 1 degree above pre-industial levels -many parts of the world experienced unusual weather patterns -severe flooding, droights, warm temperatures -blame combination of long term anthropogenic influences with 'spike' of the strongest El Nino in a generation -may increase frequency of droughdue to shifting climate belts -30 different climate zones on earth (equatorial, tropical, temperate and polar.) they are not static. Warming by 2 degrees could lead to 5% of earths land area shifting to a new climate zone -already evidence of expansion of subtropical deserts
impacts of forest loss
UN described forests as being 'fundamental' to human well-being. Over 1.6 billion depend on it, 90% are the poorest in socities -deforestation affecred 13 million hectares per year (2000-2010). balanced by afforestaion -1990-2015 the rate of net global deforestation slowed down by more than 50% and total forest carbon emissions decreased by 25% according to FEO 13% of forests now classed as conserved Brazil and USA have largest national parks. -protective legislation combined with greater involvement of local communities in panning.
energy portraits of the USA and france
USA and france shown to rank 2nd and 10th -total comsumption of france is 1/10 of USA -difference is explained by the difference in population -climate is another factory. US consumption refelcts the fact that large areas experience extremes of heat and cold, requires large inputs of energy into heating lighting, air conditioning -carbon fuels produce 82% of the energy consumed in thr USA -only 10% of energy comes from renewables and 8% from nuclear enegy France:50% of its energy coming from fossil fuels, 10% from rrenewables and 41% gtom nuclear energy -france is a major player in the nuclear power industry -has over 50 nuclear reactors in operation -France: Imported 46% of energy, all of its natural gas and oil are imported, and uranium it needs for its nuclear power stations -USA: only imports 15% of its primary energy. means it is more energy secureq
Ocean health
WFF warns that climate change is affecting ocean temps, the supply of nutrients, ocean chemistry, food chains, wind systems, ocean currents and extreme events such as cyclones Changes : bleaching, acidification, rising sea levels and loss of sea ice. These changes affect the distribution, abundance, breeding cycles and migrations of the marine plants and animals that millions of people rely on Changes to marine food web from global warming. Poses threats for a large proportion of the planet
Physival pump
based on the oceanic circulation of water (upwelling,downwelling and the thermohaline current) CO2 in the oceans is mixed more slowly than in the atmosphere, large spatial differences the colder the water, the more potential for CO2 to be absorbed. Co2 concentration is 10% higher at the deep ocean than at the surface -Polar oceans store more CO2 than tropical oceans warm tropical waters release CO2 to the atmosphere, colder oceans take in CO2 from the atmosphere -major ocean currents (north atlantic drift) moves waters from tropics to poles, water cools and absorbs more CO2.
Mismatch between fossil fuel supply and demand: coal
consumption of coal is declining relative to the other 2 fossil fuels, production continues to incrrease. -China is the largest producer, followed by USA. -Long way behind come australia, india and indonesia. Mismatch between the distributions of coal production and consumption appears to be small, in that China and the USA are clearly the two largest consumers. -coal is characterised by high transport costs relative to a low energy density
UK forests
forest cover in the UK dropped from 80% to under 10% by end of 19th century Forestry commission planted in wales, scottish highlands and lake district. Forest cover increased by 25% (1870-1947) and 50% (1948-1995) 2016-13% of the UK was forested
coal formation
formed from remains of trees and plants -ANTHRACITE is the hardest coal, has the most carbon and higher energy content -BITUMINOUS coals are next in hardness and carbon content -SOFT COALS such as lignite and brown coal are lower in carbon (25%-35%) and energy potential, global source of energy -PEAT is the stage before coal, it is an important carbon and energy source
following aspects of energy security:
four important aspects to the supply: avaliability, affordability, reliability -requires accurate prediction of future energy demands -those countries that are likely to be most energy secure will be those that are able to meet all or most of their energy needs from within their boundaries
Terrestrial soil
from plant materials: micro-organisms break most organic matter down to Carbon dioxide in a process that can take days in hot, humid climates -can take decades in a colder climate (1500 PgC)
mismatch between fossil fuel supply and demand: gas
global gas production is dominated by the USA and Russia. -suppliers found in middle east, asia and canada. -gas production has a global but uneven spread
environmental priorities
governments investing in renewable energy (solar panels and wind turbines) -cost of a 'green energy policy' could have a slightly depressing impact on consumption
resilient agricultural systems
higher tech, dought tolerant species help resistance to climate cba ge -low tecb measures generate healthier soils, help to absorb co2 and water storage: selective irrigation, cover crops, crop rotation, reduced ploughing, agroforestry Costs: more expensive, seeds and breeds unavaliable to poor subsitence farmers -high energy costs from indoor and intensive farming -generic modification is still debated
fluxes
measurements of the rate of flow of material between the stores.
energy players
meeting the demand for energy involves energy pathways from producer to consumer at both ends of such pathways, there are influential players with involvements in the energy business. energy companies and the governments of energy producing countries governments at the demand end, as well as a range of consumers players/companies responsible for the movement and processing of energt
what does the carbon cycle also rely on
ocean and terrestrial photosyntehisis. -regulates the composition of the atmosphere, and how soil health and ecosystem productivity is influenced by stored carbon
Biological pump
oceanic sequestration of CO2 to oceans by phytoplankton (marine plants float near the ocean surface to access sunlight). phytoplankton have rapid growth rates (net primary productivity), especially in shallow water. Arctic and Southern ocewans are very productive areas Carbon is then passed up the food chain by consumer fish and zooplankton which release CO2 back into the water and atmosphere -most of carbon is recycled in surgace water. only 0.1% reaches the sea floor after the dead phytoplankton sink, decompose or turned into sediment. phytoplankton sequester over 2 billion metric tonnes of CO2 annually to the deep ocean
Atmospheric
store carbon as greenhouse gases with a lifetime of up to 100 years
What is carbon also called?
the 'building block of life'
biological or physical carbon cycle
the fast component of the carbon cycle has relatively large exchange fluxes and 'rapid' reservoir turnovers of a few years up to millennia. Carbon is sequestered in and flows between the atmosphere, oceans, ocean sediments
ecoonmic development
the public perception will depend very much on the level of economic development and the standard of living. -higher these are, the less the sensitivity to energy costs
resevoir turnover
the rate at which carbon enters and leaves a store is measured by the mass of carbon in any store divided by the exchange flux
petagrams (Pg) or Gigatonnes (Gt)
the units used to measure carbon
terrestrial sequestration
this part of the carbon cycle has the shortest time scale Primary producers- plants- tale carbon out of the atmosphere through photosynthesis and release CO2 back into the atmosphere through respiration Consumer animals eat plants, carbon from the plant becomes part of its fats and proteins Micro-organisms and detritus feeders such as beetles feed on waste material from animals and becomes part of mico-organisms After plant and animal death, tissues such as leaves decay faster. Decomposition is fastest in tropical climates with high rainfall, emperatures and oxygen levels, it is very slow in cold, dry conditions or where there is a shortage of oxygen. Arctic bioms, ecosystems are locked down by extreme cold
biofuels in brazil
took action in 1970s to diversify its energy sources -invested in alternative energy sources 4% of its energy comes from renewable sources 90% of new passanger vehicles have flex-fuel engines hat work using combination of petrol and sugar cane ethanol, led to significant reduction in the countrys carbon dioxide emissions -brazil is now the worlds largest producer of sugar cane -leading expoerter of sugar and ethanol =since 2003 the area platned with sugar cane has increas,ed set to double by 2018 -concentrated in the central southern region -less agriculture (cattle ranching) -resulted in large scale clearance of tropical rainforest
grassland conversion
two main types of grassland Temperate grasslands have no trees and a seasonal growth pattern -those with fertile chernozem soils (important carbon store) prized for agriculture and hence suffer most degradation -only 2 of north americas prairies remain from land conversion Tropical grassland have scattered trees Land conversion is increasing despite infertile soils (Africa Serengeti) carbon cycle disrupted in grasslands that are used to intensively for animals or ploughed -rapid increase in population and changes to sedentary farming -effects of climate change -soil and ecosystem degradation is workide issue
thermoline circulation
vital componant of the global ocean nutrient and carbon dioxide cycles -ocean currents circulate carbon, with water flows equivilant to over 100 times that of the ocean river. warm surface waters are depleted of nutrients and CO2, enriched again as they travel through the conveyer belt as deep or bottom line ofoundation of the planets food chain depends on the cool, nutrient- rich water that supports algae and seaweed growth. Circulation also helps shift carbon in the carbonate pump cycle from upper to deeper waters balance of total carbon uptake and carbon loss from the ocean is therefore dependent on organic and inorganic processes at acting at both surface and deep ocean locations. Recent research has shown slowing of this storgage Increased oceanic acidifiation due to increased CO2 reduces the capacity for extra CO2 storage.
important drivers of the carbon cycle
water cycle
mismatch between fossil fuel demand and supply: oil
well over half comes from the two international groups of OPEC and North ameria. -relatively small amount of oil production in oil-thirsty europe shows an important mismatch -BRIC countries also rank among oil producers USA, china and India are major importers of oil. -other big oil consumers are asia/europe demand as a transport fuel, there is no substitute -deeper global market and differences between consumers and producers
Wetlands and peatlands
wetlands that contain peat, an organic sediment, are important carbon stores. -Many peatlands formed during the Halocene have been a store for thousands of years.
