The atmospheric carbon dioxide (CO₂) concentration is intimately linked to global climate: increased CO₂ causes a rise in surface temperature and an intensification of the water cycle. These climatic changes increase the chemical weathering of rocks, which in turn reduces the atmospheric CO₂ concentration. This is called the climate-weathering feedback. As this feedback stabilizes the CO₂ concentration and temperature, it is also referred to as the "Earth's thermostat". This thermostat works on a timescale of hundred thousands of years...

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