A system for removing carbon dioxide from an atmosphere forming part of a global thermostat to reduce global warming which can increase availability of renewable energy or non-fuel products such as fertilizers and construction materials, the global thermostat comprising a plurality of such systems scattered across the globe that act by regulating the amount of CO 2 in the atmosphere and hence the greenhouse effect caused by carbon dioxide and other gas emissions, the system comprising: an air extraction system comprising an air contactor unit arranged to pass atmospheric air through a medium that collects carbon dioxide from the atmosphere, the medium comprising a vertically or horizontally oriented porous, pancake shaped substrate (600, 602, 700, 702) capable of extracting CO 2 from the atmosphere, the medium comprising an amine attached to the surface of the substrate (600, 602, 700, 702), the substrate being moveable between a first position in which carbon dioxide laden air at ambient temperature is brought into contact with the medium carried by the substrate to remove carbon dioxide from the air, and a second position in which process heat at a temperature less than about 120°C is directed at the substrate to remove carbon dioxide from the medium; and a collection system that isolates the removed carbon dioxide to a location for at least one of sequestration, storage and generation of a renewable carbon fuel or non-fuel products such as fertilizers and construction materials; and one or more energy sources that supply process heat to the air extraction system to remove the carbon dioxide from the medium and which can regenerate it for continued use, wherein the one or more energy sources (10, 20) are selected from the group of primary energy sources consisting of: fossil fuel, geothermal, nuclear, solar, biomass and other renewable energy sources and exothermic chemical processes whose use can result in a supply of process heat. an air extraction system comprising an air contactor unit arranged to pass atmospheric air through a medium that collects carbon dioxide from the atmosphere, the medium comprising a vertically or horizontally oriented porous, pancake shaped substrate (600, 602, 700, 702) capable of extracting CO 2 from the atmosphere, the medium comprising an amine attached to the surface of the substrate (600, 602, 700, 702), the substrate being moveable between a first position in which carbon dioxide laden air at ambient temperature is brought into contact with the medium carried by the substrate to remove carbon dioxide from the air, and a second position in which process heat at a temperature less than about 120°C is directed at the substrate to remove carbon dioxide from the medium; and a collection system that isolates the removed carbon dioxide to a location for at least one of sequestration, storage and generation of a renewable carbon fuel or non-fuel products such as fertilizers and construction materials; and one or more energy sources that supply process heat to the air extraction system to remove the carbon dioxide from the medium and which can regenerate it for continued use, wherein the one or more energy sources (10, 20) are selected from the group of primary energy sources consisting of: fossil fuel, geothermal, nuclear, solar, biomass and other renewable energy sources and exothermic chemical processes whose use can result in a supply of process heat.