Imagine if the global annual average temperature were about 5°F colder than it is presently.
Not quite sure how to? OK, consider this: During the Little Ice Age—a period extending from about the 1500s to the mid-1800s and thought to be one of the coldest periods during the past 10,000 years or so—the earth’s average temperature may have been 2-3°F colder than present. Associated with the Little Ice Age are all sorts of human calamities—widespread crop failures, plagues, famines, population declines, glacial encroachments, etc. For a collection of descriptions of all the fun times that a colder climate brings, take a gander at the Wikipedia page on the Little Ice Age. After spending a few minutes there, you’ll see that these were not high times for humans.
Now, consider a temperature decline twice that much. That can’t be good.
Yet that’s apparently where we would be had human ingenuity not come along.
According to a new study just published in the journal Geophysical Research Letters, the global climate would be about 5°F colder than present were it not for human carbon dioxide and methane emissions.