● Arctic region is warming 2x as fast as the global average (ARCTIC AMPLIFICATION) • Melting permafrost releases CO2 and
CH4, increasing the concentration of greenhouse gases and leading to global temperature rise/further ice melts
● Climate change is altering the Arctic tundra ecosystem • Rapid warming contributes to extensive melting of sea ice in summer
as well as greatly reducing snow cover and permafrost
● Shrubs and trees, previously unable to survive in tundra, have started to establish themselves; likewise, animals in Alaska (the
red fox) has spread northwards and now competes with the Arctic fox for food and territory BUT not all scientists agree melting
permafrost = release stored carbon as CO2 and CH4
● Some studies show as permafrost thaws, the stored carbon remains in the soil and is used by new vegetation
● Warmer temperatures accelerate decomposition, releasing carbon and nutrients • Nutrients encourage plant growth and the
removal of carbon from the atmosphere through photosynthesis (decreasing levels of greenhouse gases in atmosphere)
● Ice sheet lost an average of 30Gt per annum during 1991 to 2001, however this flux of loss rapidly increased during 2002 to
2011 where 147Gt of ice was lost
● Amount of carbon stored is at 1330-1380bn tons of carbon (almost 2x as in the atmosphere) - of this amount 800-1000bn tons
is prevailingly frozen, with the remainder contained in seasonally travelled soils
, Carbon - Biofuels in Brazil
● 1970s - Brazil invested in alternative energy sources such as hydroelectricity and more recently biofuels
● bio-ethanol production is cheaper than petrol and was used as vehicle fuel and since this Brazil has become the world's leading
bio-ethanol producer and a leader in cutting carbon emissions
● Today, 4% from renewable sources and 90% of vehicles in Brazil contain flex-fuel engines that work using any combination of
petrol sugarcane ethanol - significant reduction in the country's carbon dioxide emissions
● Brazil's the largest producer of sugarcane, reading exporter of sugar and ethanol BUT this can lead to displacement of
agriculture (particularly cattle pasture) = tropical rainforest has been cleared for said cattle pasture -> cancels out carbon
emission
● Biofuel is renewable = lower emissions, is biodegradable and easily grown without needing specialist machinery; BUT it takes
land from production, needs pesticides and fertilisers which uses fossil fuels in their production, requires large volumes of water,
clearing forest to grow this crop = loss of a carbon sink and increased emissions from the deforestation (30-60% higher than
savings from using biofuels) again throwing doubt on the crop's 'carbon neutrality'
● Since 2003, Brazil's use of bio-ethanol has reduced the country's CO2 emissions by more than 350 million tons BUT some
biofuels cannot be regarded as 'carbon neutral'
● Biomass requires a fuel to 'kick start' burning i.e. coal is needed to 'fire up' the biomass and some biomass fuels can therefore
produce between 150% and 400% more CO2 than coal
● Social unrest occurred -> farm workers lost land to grow sugar canes and cannot grow food for themselves = many farmers
move to cities; food shortages = higher food prices
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