"The effects of La Niña were sort of muddled together with the effects of the enhanced North Atlantic Oscillation," said Ed O'Lenic of the Climate Prediction Center.
Some of the extremes seen this spring could be just a taste of what we might see in a future, warmer world – though scientists do not tie particular events to climate change.
Floods & drought
The historic flooding of the Mississippi and Missouri rivers has dominated headlines lately. [Mightiest Floods of the Mississippi River]
The floods were caused by heavy winter snows and torrential spring rains, driven by La Niña and the North Atlantic Oscillation. All that water ran into the two rivers, and the US Army Corps of Engineers has been forced to release record amounts of water from the Missouri's reservoirs to cope with the flooding. As the Midwest continues to be soaked by rainstorms and parts of the snowpack have yet to melt, the Corps may find itself releasing reservoir water through mid-August.
Extreme floods could be a common sight in a warmer world, Mr. Karl said. The hotter the Earth's atmosphere gets, the more water it can hold; this could cause more intense rain and snow in certain parts of the world.
