Last September’s widespread flooding in northeast Colorado, which saw just over 17 inches of rain in one week in the city of Boulder, was not made more likely or more intense by the influence of human-induced climate change on atmospheric moisture.

Temperature extremes have been pretty unusual across the United States so far in 2014. Looking back over this time period quickly reveals at least part of what was going on: the polar jet stream got into a serious rut.

It's the time of year for potentially toxic algae blooms in Lake Erie. But the stage for most blooms is set in spring.

Never in the historical record have such large areas of the country experienced such radically different temperature extremes as they have so far in 2014.

Earth’s hottest periods occurred before humans existed. Those ancient climates would have been like nothing our species has ever seen.

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