Just how much will global temperature rise in response to increases in atmospheric carbon dioxide? This is one of the key questions that climate scientists need to answer. According to the climate models used in the most recent report from the Intergovernmental Panel on Climate Change (IPCC), doubling the amount of carbon dioxide in the atmosphere from pre-industrial levels is expected to warm Earth by about 3 degrees Celsius (5 degrees Fahrenheit), once the atmosphere and oceans spend a few years or decades adjusting and reaching a balance.
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