Design of global climate control based on fuzzy systems with concept of carbon emissions

PLOS One Design of global climate control based on fuzzy systems Fig 11. Nonlinear global carbon–cycle fuzzy control scheme using output feedback. https://doi.org/10.1371/journal.pone.0333846.g011 1. Atmospheric (𝜉A). 2. Terrestrial biosphere (𝜉T). 3. Surface ocean (𝜉S). Three carbon compartments are contained in the model: atmosphere (𝜉A), terrestrial bio- sphere (𝜉T), and surface ocean (𝜉S). Deep ocean and fossil fuel reserves are designated by the letters D and F. The amount of Carbon contents is always expressed in PgC and fluxes in PgC year–1. Adding carbon to the system is the result of two external fluxes. As 𝜆D→S is constant, As a result of the combustion of fossil fuels, CO2 is released into the atmosphere, whereas 𝜆F→A = 𝜆F→A(t) is depend upon the time, fossil fuel burns and releases carbon diox- ide into the atmosphere. Fig 6 shows how 𝜆F→A = u(t)p is defined by the input control u(t) and the output human demand p. Surface seawater and deep ocean water are the only two places where carbon can leave the system. A flux of this kind is denoted by the number 𝜆S→D. As a result of the model, the following fluxes exist from compartment X to compartment Y, all given in PgC year –1. 𝜆A→T = 60 (𝜉A/700)𝛾1 , 𝜆A→S = 100𝜉A/700 𝜆T→A = 60𝜉T/3000, 𝜆S→A = 100 (𝜉S/1000)𝛾2 𝜆S→D = 45𝜉S/1000, 𝜆D→S = 45. (9) It is controlled by two parameters, 𝛾1 = 0.2 and 𝛾2 = 10.0 which control the fluxes between the atmosphere and biosphere, as well as between the surface ocean and atmosphere. Three

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