A System Dynamics Approach to Global Warming (Noah) Junho Kang

Purpose/Goals Create a convincing model of global warming scenario Complicated enough to explain the whole scenario to a reasonable extent, but simple enough to be understood easily and applied

Scope of the Project Estimate, to a certain degree, the effects that increasing amount of Carbon Dioxide gas will have on the Earth's atmosphere over a fixed period of time. The "effects" currently include, but is not limited to, global temperatures, frequency of hurricanes, methane release, and other consequences that will arise from increasing global temperature.

Expected Results Direct Cause-and-effect relationship between Earth’s Global Temperature and Carbon Dioxide Concentration Demonstrate the negative impacts of Global Warming Accelerating Cycle of Global Warming

Background Daisyworld Parallel Computing-based Climate Simulations System Dynamics Modeling and Agent- based Modeling

Theory System Dynamics Modeling Netlogo STELLA Complex System Modeling

Current Progress on Model Five Stocks: Land, Soil, Atmosphere, Ocean and Fuel Eight Flows: External Addition, Photosynthesis, Respirations Variables

System Dynamics Model (Carbon Cycle) OceanAtmosphereFossil Fuel SoilLand Biota Out/In (Negligible)

System Dynamics Model (Secondary) Global Temperature IceHurricanes Albedo Ocean Temperature Methane in Atmosphere

Variables Used Fossile Fuel: Amount of Carbon inside Fossile Fuel Atmosphere: Amount of Carbon (Mostly Carbon Dioxide and Methane) inside Atmosphere, directly affects Global Temperature Land Biota: Amount of Carbon present in Land organisms, like plants. Help control the amount of carbon by Photosynthesis/Respiration

Variables Used - Continued Soil: Amount of Carbon present in Soil, controls the amount of Carbon Dioxide in Atmosphere by respiration and slowly recovers the amount of Fossil Fuel. Ocean: Amount of Carbon present in Ocean, mostly in the form of Carbon Dioxide and Methane dissolved in water. Potentially very important, helps control amount of carbon by dissolving it.

Equations Used External Addition (Fossil Fuel → Atmosphere, mostly) Photosynthesis (Land → Atmosphere)((Pmax * (pCO2_eff / (pCO2_eff + Khs))) * (1 + (Tsens_p * global-temp))) Plant Respiration (Atmosphere → Land) – (Photosynthesis *.5) / dt

Equations Used - Continued Litter Fall (Land → Soil) – (50 * (Land / 610)) Soil Respiration (Soil → Atmosphere) – ((49.4 / INIT_Soil) * Soil * (1 + (Tsens_sr * global-temp))) Runoff (Soil → ) – (0.6 * (Soil / INIT_soil))

Progress on Code - 1QT Output system consisting of an Output file and a graph Automatic external addition correction checks 10,000 ticks during run

Progress on Code - 2QT External Addition Cycle Netlogo Chart Output

Results Current results show a relationship between global temperature and Carbon Dioxide concentration in Atmosphere. As Carbon Dioxide concentration in Atmosphere increases, Earth’s self- balancing system starts working, and attempts to balance the temperature. Climate change is accelerated by melting of ice and release of Methane gas.

Results – Before Fuel Addition

Results – After Fuel Addition