Horrendous wildfires. Oppressive heat waves. Devastating droughts. Flooding from giant deluges. And a powerful freak wind storm called a derecho.
These are the kinds of extremes climate scientists have predicted will come with climate change, although it's far too early to say that is the cause. Scientists have yet to pinpoint the reason that 3,215 daily high temperature records set in the month of June.
Scientifically linking individual weather events to climate change takes intensive study, complicated mathematics, computer models and lots of time. Sometimes it isn't caused by global warming, because weather is always variable.
The problem appears to be local. Europe, Asia and Africa aren't having similar disasters now, although they've had their own extreme events in recent years.
Since at least 1988, climate scientists have warned that climate change would bring, in general, increased heat waves, more droughts, more sudden downpours, more widespread wildfires and worsening storms. In the United States, those extremes are happening here and now.
So far this year, more than 850,000 hectares have burned in wildfires, more than 113 million people in the U.S. were in areas under extreme heat advisories last Friday, and two-thirds of the country is experiencing drought while deluges flooded Minnesota and Florida earlier in June.
As recently as March, a special report on extreme events and disasters by the Nobel Prize-winning Intergovernmental Panel on Climate Change warned of "unprecedented extreme weather and climate events." Its lead author, Chris Field of the Carnegie Institution and Stanford University, said Monday, "It's really dramatic how many of the patterns that we've talked about as the expression of the extremes are hitting the U.S. right now."
"What we're seeing really is a window into what global warming really looks like," said Princeton University geosciences and international affairs professor Michael Oppenheimer.
Such patterns haven't happened only in the past week or two. The spring and winter in the U.S. were the warmest on record and among the least snowy, setting the stage for the weather extremes to come, scientists say.
Since Jan. 1, the United States has set more than 40,000 hot temperature records, but fewer than 6,000 cold temperature records, according to the National Oceanic and Atmospheric Administration. Through most of last century, the U.S. used to set cold and hot records evenly, but in the first decade of this century America set two hot records for every cold one, said Jerry Meehl, a climate extreme expert at the National Center for Atmospheric Research. This year the ratio is about 7 hot to 1 cold. Some computer models say that ratio will hit 20-to-1 by midcentury.
"In the future you would expect larger, longer more intense heat waves and we've seen that in the last few summers," NOAA Climate Monitoring chief Derek Arndt said.
While at least 15 climate scientists told The Associated Press that this long hot U.S. summer is consistent with what is to be expected in global warming, history is full of such extremes, said John Christy at the University of Alabama in Huntsville. "The guilty party, in my view, is Mother Nature," he says, and not climate change.