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    Analytically tractable climate–carbon cycle feedbacks under 21st century anthropogenic forcing
    (München : European Geopyhsical Union, 2018) Lade, Steven J.; Donges, Jonathan F.; Fetzer, Ingo; Anderies, John M.; Beer, Christian; Cornell, Sarah E.; Gasser, Thomas; Norberg, Jon; Richardson, Katherine; Rockström, Johan; Steffen, Will
    Changes to climate–carbon cycle feedbacks may significantly affect the Earth system's response to greenhouse gas emissions. These feedbacks are usually analysed from numerical output of complex and arguably opaque Earth system models. Here, we construct a stylised global climate–carbon cycle model, test its output against comprehensive Earth system models, and investigate the strengths of its climate–carbon cycle feedbacks analytically. The analytical expressions we obtain aid understanding of carbon cycle feedbacks and the operation of the carbon cycle. Specific results include that different feedback formalisms measure fundamentally the same climate–carbon cycle processes; temperature dependence of the solubility pump, biological pump, and CO2 solubility all contribute approximately equally to the ocean climate–carbon feedback; and concentration–carbon feedbacks may be more sensitive to future climate change than climate–carbon feedbacks. Simple models such as that developed here also provide "workbenches" for simple but mechanistically based explorations of Earth system processes, such as interactions and feedbacks between the planetary boundaries, that are currently too uncertain to be included in comprehensive Earth system models.
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    The world’s biggest gamble
    (Hoboken, NJ : Wiley, 2016) Rockström, Johan; Schellnhuber, Hans Joachim; Hoskins, Brian; Ramanathan, Veerabhadran; Schlosser, Peter; Brasseur, Guy Pierre; Gaffney, Owen; Nobre, Carlos; Meinshausen, Malte; Rogelj, Joeri; Lucht, Wolfgang
    The scale of the decarbonisation challenge to meet the Paris Agreement is underplayed in the public arena. It will require precipitous emissions reductions within 40 years and a new carbon sink on the scale of the ocean sink. Even then, the world is extremely likely to overshoot. A catastrophic failure of policy, for example, waiting another decade for transformative policy and full commitments to fossil‐free economies, will have irreversible and deleterious repercussions for humanity's remaining time on Earth. Only a global zero carbon roadmap will put the world on a course to phase‐out greenhouse gas emissions and create the essential carbon sinks for Earth‐system stability, without which, world prosperity is not possible.