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Geography Lecture #5 - October 29 - November 7 2013.docx

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Department
Geography
Course
Geography 1400F/G
Professor
Anthony Weis
Semester
Fall

Description
Michael Watts – food security in Sahel, to deal with periodic drought and seasonality he says th that over the course of 20 century, that in the region we need to understand and come up with strategies on how to cope and stabilize the drought, trajectory of society and economy over time -chronic food insecurity since 19070’s -anthropogenic climate change – Inter governmental panel on climate change – international organization that brings together scientists and work on documents that focus on arrays of climate change – since early 90’s they have said Africa is exceptionally vulnerable (arid and semi-arid regions and well as tropics are the most vulnerable places in the world) -if things continue (business as usual) and greenhouse gases continue at their rate, the artic is most vulnerable to heating (heated 2x more than any other region in the world so far). Certain regions in Africa will increase by 3C – UN development program made a report on climate change, and stated climate change overarches everything in human development (less capacity to adapt to the changing world) -2013 summer ITCZ affirmed that weather is becoming more seasonal and unpredictable (and what people working in agriculture are saying) -3 billion people live in rural places, 2.5 billion are involved in farming and the poorest and most food insecure people are farmers (therefore they are the most vulnerable and more vulnerable to climate change – areas in the semi-arid tropics and Sahel) -changing climate seen in lake chad (on the border of Niger, Chad and Nigeria) – in the last 3 decades it has shrunk by more than half – areas in red are only seasonal. Overall surface area and volume has decreased drastically -atmospheric footprint – there are disparities around the world. Person in Canada has bigger carbon footprint than person in Sahel -Canada and US = 5% of humanity. China recently passed the US in aggregate carbon emission -poorest half of humanity makes a miniscule impact on Carbon emissions (in South America and South-East Asia – Brazil is rising) -reducing global CO2 emissions is fraught with a lot of geopolitical tension (a lot of these tensions are in the US, Europe, Japan and the most affected are sub-Saharan Africa). SSA has become very vocal at multi-lateral negotiations on climate change – semi arid tropics contain 22% of humanity in SSA and South Asia (poorest areas in world). These are the most agrarian populations in the world -carbon is constantly in motion -how are humans affecting carbon cycle (part of biogeochemical cycle) – elements move through a whole range (reservoirs and sinks) of places on earth. People can store carbon for about 90 years, and it is stored in plants for a short amount of time. Therefore there is a cycle of carbon, nitrogen, potassium and phosphorous. The cycle is in atmosphere (air), hydrosphere (water), biosphere (global sum of all ecosystems), pedosphere (living skin of the earth) and lithosphere (crust of earth). Desertification = reduced carbon in cycle -reservoirs- -both biotic and abiotic and can be rocks – fossil fuels are reservoirs of carbon that have been locked up for millions of years. Reservoirs have a vastly different time scale (i.e. plants vs. coal) -other carbons are constantly moving in the cycle (average time a CO2 molecule stays in atmosphere – 100 years) -RESIDENCE TIME: average amount of time that element resides in a given reservoir -a large number of coastal areas are being affected by eutrophication – nitrogen and phosphorus (excessive contribution of nutrients). They lead to growth of algae, and algae chokes out plants life and oxygen in water therefore killing fish life. -in the Mississippi there is a lot of excess nitrogen and potassium being emitted, goes into gulf of Mexico and therefore huge algae blooms (product of industrial agricultural runoff – destabilization of biogeochemical cycle). The dead zone at the outlet in the Gulf of Mexico is the size of New Jersey. This chokes off aquatic ecosystems - David W. Schindler – Algal Bowl (western Lake Erie) – 2011 greatest algae, 2.5x greater than ever recorded. Product of too much nitrogen and phosphorus and destabilization of biogeochemical cycle -carbon is constantly moving. Plants sequester carbon and create pedosphere (it is a huge carbon sink in the soils). Some carbon from soil makes its way into atmosphere. As soil lose nutrient content, they become degraded and carbon is released (destabilization of biogeochemical carbon cycle) -biggest exchange of carbon is between atmosphere and ocean -ocean = huge carbon sink (constantly absorbing and releasing carbon) -humans added different dimension of carbon cycle (fossil energy that has been locked up for millions of years) -there is fossilized carbon that once came from pedosphere and biosphere (from the living world once upon a time). This carbon was locked out of the carbon cycle. -Most fossil energy comes from time of dinosaurs (warm, wet and biologically productive) – compaction and compression makes these fossil fuels – ancient photosynthesized energy -Late cretaceous period – arctic had tropical plant life (ferns) and oceans had very different water -most oil is from algae, zoo plankton and shallow biologically productive sea beds (tar sands in Alberta) -different chemical processes create different fossil fuels that get densely trapped in earth’s lithosphere -greenhouse gases have been variable in earth’s history -coastal ecosystems created a lot of earths coal supplies (humans in ancient times had small use of coal and oil). Most of it explodes in industrial revolution – last 200 years -200 years – carbon reservoirs have been trapped and therefore humans have affected carbon cycle. More carbon moves between atmosphere and ocean (more than fossil energy) -fossil energy was set outside carbon cycle for millions of years therefore it is affecting the chemistry of carbon cycle -top 20% is responsible for 50% of worlds CO2 emissions -fossil energy from – industry, movement of things over space, average food item moves 1500 km from land source to mouth, mobility of humans (air travel, cars, bus etc.) – all of these things are highly dependent on oil -oil permeates industrial society – in US in (1969-1995) the number of cars grew 6x than the human population. This shaped how our cities are organized -fossil fuel = movement of food and how food is produced (fertilizers – elements injected into soil and moved over land – nitrogen, potassium and phosphorus) -to make nitrogen fertilizer (most important fertilizer on earth) – it is almost wholly dependent on natural gas. It is responsible for about 2% of fossil energy consumed on world scale -agrochemical = petrol chemicals (heating barns and moving food) th -19 century = US burning wood for energy -fossil fuels – 4/5ths of energy consumed today NEXT DAY -fossil energy is enormous part of economy and destabilizing -International Energy Agency – leading agency documenting words energy supply (based in Paris) – started during energy crisis in 70’s (energy supply, consumption, future)…have tracked worlds energy supply since 70’s. They have this term called “Net Primary Energy Supply = aggregate all energy used to heat homes, transportation, powering industry, all this energy (fossil energy = it drives 4/5s of world energy) -oil is the biggest single fossil energy source (1/3 of worlds total energy supply/net primary energy supply…its key source of liquid fuel like gasoline)…ethanol is also being used as an energy source, you need industrial corn monocultures to do this…95% of worlds transportation energy comes from oil (biggest fuel source) -Canada + US are 5% of humanity and India + China=2/5 of humanity…map from 1990s says that US + Canada consume 45% of worlds gasoline consumption -IEA says crude oil consumption is 80 million barrels of oil are consumed in the world today (US and Europe consume 50% of this). Asia’s consumption of Asia has tripled in 30 years - Atmosphere (air), hydrosphere (water), biosphere (global sum of all ecosystems), pedosphere (living skin of the earth) and lithosphere (crust of earth) – are all reservoirs and sinks of carbon and other chemicals/elements -the biogeochemical cycle of carbon is a huge factor of climate change – carbon cycle runs without humans (duh), it’s essential to life. Biggest reservoir of carbon also fluxes is the ocean -the lithosphere – biggest place where carbon is stored but it isn’t actually moving around (there is a small flux since its locked into the soils and rocks) -fossil energy = ancient carbon from Mesozoic era -oil production is mostly from algae (very photosynthesized energy that is compacted and chemically changed) -humans have dug into source of ancient carbon – important fact – tropical deforestation (deforestation in general really) has been happening in the last 200 years and has had an enormous impact on climate change. A flux because of deforestation – huge release of carbon into atmosphere and if the forest isn’t regenerated there is loss in carbon sequestration capacity in the future…deforestation = carbon release in atmosphere and ability to absorb carbon, therefore more carbon ha
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