Climate System + Carbon PDF

Systems Dynamics: Climate System + Carbon Global Carbon Cycle – Systems Thinking There are many biogeochemical cycles with move materials through Earth’s systems Carbon cycle Nitrogen cycle Phosphorus cycle Water cycle These cycles are interconnected processes...

Systems Dynamics: Climate System + Carbon Global Carbon Cycle – Systems Thinking There are many biogeochemical cycles with move materials through Earth’s systems Carbon cycle Nitrogen cycle Phosphorus cycle Water cycle These cycles are interconnected processes A disturbance to cycle affects other cycles Human activity can affect the flow of material through these cycles What do you need to know about Carbon? Carbon is a molecule found throughout the planet When structure are comprised of carbon and hydrogen atoms, they are called ”organic” molecules All living organisms are comprised of 96% carbon (C), hydrogen (H), oxygen(O) and nitrogen (N) Carbon in many forms: CO2, methane (CH4) Sugars, DNA, proteins, lipids in living (and dead) organisms HCO3- in the water Dissolved carbon in the soil CaCO3 (calcium carbonate) Global Carbon Cycle The carbon cycle is a system with components (such as carbon pools or carbon reservoirs). Carbon reservoirs which store carbon are called carbon sinks (ie, ocean). Reservoirs which release carbon are carbon sources (fossil fuels) Processes transform input to output that move from component to component. Links between components are also called couplings, specifically in the carbon cycle these are called carbon fluxes. Biological Carbon Cycle Biological Carbon Cycle Carbon Cycle 1. Photosynthesis converts CO2 into organic molecules 2. Organic molecules passed along food chain by consumers 3. Cellular respiration returns CO2 to atmosphere 4. Decomposers break down detritus, releases CO2 Balance between cellular respiration, decomposition and photosynthesis How does carbon change its state? Natural processes (carbon fluxes) that move carbon atoms 1. Photosynthesis – allows producers (plants, algae, bacteria) to convert sunlight (solar energy) into chemical energy (food for consumers) 2. Cellular Respiration – allows organisms (mostly consumers) to utilize energy from producers (or other consumers) to grow and develop 3. Decomposition – allows decomposers (bacteria, fungi) to convert organic carbon molecules to inorganic carbon molecules Photosynthesis The process by which producers use sunlight to synthesize food from CO2, H2O and other nutrient Where do the inputs come from? Solar energy from the sun CO2 comes in through the leaves H2O (and nutrients – N,P,K) absorbed from the soil by roots Where do the outputs go? Sugars go to rest of plant, used to grow plant tissues O2 is released through the leaf Consumers eat the sugars when they eat the plants Cellular Respiration The breakdown of organic molecules in living organisms to release energy, used to build its own tissues Allows for growth and development in organisms There are other metabolic process that breakdown organic molecules and release CO2 Where do the inputs come from? Plants tissues (sugars) other organisms that have consumed plants O2 from the atmosphere H2O from fresh water Where do the outputs go? CO2 is released when we breathe Water released when we sweat, urinate Balance: Photosynthesis + Cellular Respiration Cellular Respiration Geological Carbon Cycle Geological Carbon Cycle How does carbon change its state? Long-term carbon fluxes 1. Volcanism – releases CO2 from centre of Earth 2. Dissolution – CO2 dissolves in water to become H2CO3 (carbonic acid) Mildly acidic (H+ ions) Carbonic acid in rain water, in clouds, in oceans 3. Rock Weathering – H2CO3 in rain breaks down rocks, releases ions Produces CaCO3 = calcium carbonate (limestone, chalk, shells of marine orgs) Produces HCO3- runs off into ocean 4. Sedimentation – mineralized CO2 From minerals, dead marine organisms’ exoskeleton/shells, dead plants/animals Can become fossil fuels reserves Carbon Budget of Stock and Flux Fossil Fuels Emissions + Carbon Cycle Oil, coal, natural gas What are they? – hydrocarbon chains (lots of carbon + energy) How were they formed? Organism from the past didn’t decompose when they died Carbon in their bodies wasn’t release as CO2 into atmosphere A small deficit to atmospheric carbon at that time (outflow > inflow) over a long period of time What is the problem with burning fossil fuels now? Inflow >>> outflow of atmospheric carbon in a short period of time Causing imbalance in the carbon system Fossil Fuels Emissions + Carbon Cycle Fossil Fuels Emissions + Carbon Cycle Global Carbon Budget Notice which parts of the carbon cycle are carbon sources and which are carbon sinks Which is the largest source? Which is the largest sink? Humans Impacts + Carbon Cycle Land use changes + Deforestation Reducing forests and other photosynthetic organisms, reduces carbon sinks Slows the flow of carbon out of the atmosphere Burning plant material releases carbon into atmosphere Slash and burn agriculture Fossil Fuel use Combustion of hydrocarbons releases CO2 into atmosphere Decrease carbon reservoirs Consumption + waste Single use plastics (made from petroleum hydrocarbons), decreases carbon reservoir of fossil fuels Methane released from landfills into atmosphere when microbes break down waste Humans Impacts + Carbon Cycle Where is all the carbon released by human activity going? Only about 50% of the increased CO2 stays in the atmosphere. The rest is absorbed by the oceans and other sinks. 20 Global Carbon Cycle The global carbon cycle is impacted greatly by human activities. Global Carbon + Future In 2007, the planet has 380ppm of CO2 in the atmosphere, today it is Ref: climate.nasa.gov. Learning Objectives Construct a carbon cycle with all relevant carbon stocks and carbon fluxes (processes). Recognize the time frame differences between the geological aspect and biological aspect of the carbon bio-geochemical cycle. Identify how inflow and outflow are affected Identify carbon sinks + sources Describe the problem of human activities on the balance of the carbon cycle Learning Objectives Identify the 4 components (and material reservoirs) in our climate system. Give examples of each. Describe processes that move material between material reservoirs. Describe our climate system Construct a carbon cycle with all relevant carbon stocks and carbon fluxes. Identify how inflow and outflow are affected Describe how these changes create feedback in the carbon system Define stock, flow, and feedback Explain how the combined history of inflows and outflows determines a stock Predict what happens to stocks and flows of energy and materials when a system is perturbed Describe examples of both amplifying and stabilizing feedbacks