How much is the climate expected to warm?
How much the Earth’s climate will warm depends on how much carbon dioxide and methane continue to be put in the atmosphere. If carbon dioxide levels stabilized at twice the pre-industrial level, about 560 parts per million, the most probable warming is 3 degrees Celsius, globally averaged. It’s important to understand a couple of things about that number. Due to a phenomenon called polar amplification, the poles will warm much more, with the Arctic warming much more rapidly than Antarctica. The mid-latitudes, where the United States is, would see warming of 3 to 5 Celsius. The amount of warming also isn’t the most important aspect of global warming. Humans are very adaptable to temperature changes. But we need water for ourselves and our agricultural system, and changing precipitation patterns as a result of global warming can have enormous, and expensive, consequences for drinking water and food supplies. As a glaciologist pointed out in 1978, long before the current concern with glob
