Another nail has been driven into the anti-science coffin of global warming deniers. A peer-reviewed nail. Tomorrow a study will be published by the United States National Academy of Sciences.
James Hansen, director of the NASA Goddard Institute for Space Studies, describes the findings in "Climate change is here -- and worse than we thought."
In a new analysis of the past six decades of global temperatures, which will be published Monday, my colleagues and I have revealed a stunning increase in the frequency of extremely hot summers, with deeply troubling ramifications for not only our future but also for our present.
This is not a climate model or a prediction but actual observations of weather events and temperatures that have happened. Our analysis shows that it is no longer enough to say that global warming will increase the likelihood of extreme weather and to repeat the caveat that no individual weather event can be directly linked to climate change. To the contrary, our analysis shows that, for the extreme hot weather of the recent past, there is virtually no explanation other than climate change.
The deadly European heat wave of 2003, the fiery Russian heat wave of 2010 and catastrophic droughts in Texas and Oklahoma last year can each be attributed to climate change. And once the data are gathered in a few weeks’ time, it’s likely that the same will be true for the extremely hot summer the United States is suffering through right now.
These weather events are not simply an example of what climate change could bring. They are caused by climate change. The odds that natural variability created these extremes are minuscule, vanishingly small. To count on those odds would be like quitting your job and playing the lottery every morning to pay the bills.
Hansen uses a dice metaphor to communicate what human-caused global warming is doing to the odds of extreme weather events happening.
Twenty-four years ago, I introduced the concept of “climate dice” to help distinguish the long-term trend of climate change from the natural variability of day-to-day weather. Some summers are hot, some cool. Some winters brutal, some mild. That’s natural variability.
But as the climate warms, natural variability is altered, too. In a normal climate without global warming, two sides of the die would represent cooler-than-normal weather, two sides would be normal weather, and two sides would be warmer-than-normal weather. Rolling the die again and again, or season after season, you would get an equal variation of weather over time.
But loading the die with a warming climate changes the odds. You end up with only one side cooler than normal, one side average, and four sides warmer than normal. Even with climate change, you will occasionally see cooler-than-normal summers or a typically cold winter. Don’t let that fool you.
Our new peer-reviewed study, published by the National Academy of Sciences, makes clear that while average global temperature has been steadily rising due to a warming climate (up about 1.5 degrees Fahrenheit in the past century), the extremes are actually becoming much more frequent and more intense worldwide.
When we plotted the world’s changing temperatures on a bell curve, the extremes of unusually cool and, even more, the extremes of unusually hot are being altered so they are becoming both more common and more severe.
The change is so dramatic that one face of the die must now represent extreme weather to illustrate the greater frequency of extremely hot weather events.
Last year the National Academy of Sciences reviewed the state of global warming science in response to a request from Congress. A Washington Post editorial written after the study was released said "Climate change denial becomes harder to justify."
That's even more true, given Hansen's study. Here's some excerpts from the editorial.
“CLIMATE CHANGE is occurring, is very likely caused by human activities, and poses significant risks for a broad range of human and natural systems.”
So says — in response to a request from Congress — the National Research Council of the National Academy of Sciences, the country’s preeminent institution chartered to provide scientific advice to lawmakers.
...None of this should come as a surprise. None of this is news. But it is newsworthy, sadly, because the Republican Party, and therefore the U.S. government, have moved so far from reality and responsibility in their approach to climate change.
Seizing on inevitable points of uncertainty in something as complex as climate science, and on misreported pseudo-scandals among a few scientists, Republican members of Congress, presidential candidates and other leaders pretend that the dangers of climate change are hypothetical and unproven and the causes uncertain.
Not so, says the National Research Council. “Although the scientific process is always open to new ideas and results, the fundamental causes and consequences of climate change have been established by many years of scientific research, are supported by many different lines of evidence, and have stood firm in the face of careful examination, repeated testing, and the rigorous evaluation of alternative theories and explanation.”
Climate-change deniers, in other words, are willfully ignorant, lost in wishful thinking, cynical or some combination of the three. And their recalcitrance is dangerous, the report makes clear, because the longer the nation waits to respond to climate change, the more catastrophic the planetary damage is likely to be — and the more drastic the needed response.