Green Communications: Making “95% Certain” Mean Something.

What would you do if your doctor was 95% sure you had a serious illness?

How about if a whole room of doctors said it?

You’d take care of it.

Via the European Commission:

What would you do if your doctor was 95% sure you had a serious illness?

”The issue is not whether to believe in climate change or not.

The issue is whether to follow science or not.

The day when all scientists with 100% certainty warn you against climate change, it will be too late.

If your doctor was 95% sure you had a serious disease, you would immediately start looking for the cure. Why should we take bigger risks when it’s the health of our planet at stake?

The new IPCC report says that climate change is occurring and that is at least 95% certainty that human activities are the principal cause.

OK, got it.

Let’s dig into that 95% number. Seems like there’s some wiggle room there.

But not really. When a scientist says this, he or she is being as precise as possible.

Via AP:

What 95% certainty of warming means to scientists

But in science, 95 percent certainty is often considered the gold standard for certainty.

Let’s put it into some context. Say, the sun.

 “Will the sun come up in the morning?” Scientists know the answer is yes, but they can’t really say so with 100 percent certainty because there are so many factors out there that are not quite understood or under control.

And why is this OK? Because we don’t demand absolute proof on other things before taking steps to mitigate risk. Like car insurance.

George Gray, director of the Center for Risk Science and Public Health at George Washington University, said that demanding absolute proof on things such as climate doesn’t make sense.

“There’s a group of people who seem to think that when scientists say they are uncertain, we shouldn’t do anything,” said Gray, who was chief scientist for the U.S. Environmental Protection Agency during the George W. Bush administration. “That’s crazy. We’re uncertain and we buy insurance.”

Give it to me in a more-and-less:

The Associated Press asked scientists who specialize in climate, physics, epidemiology, public health, statistics and risk just what in science is more certain than human-caused climate change, what is about the same, and what is less.

Gravity?

They said gravity is a good example of something more certain than climate change. Climate change “is not as sure as if you drop a stone it will hit the Earth,” Princeton University climate scientist Michael Oppenheimer said. “It’s not certain, but it’s close.”

The age of the universe?

Arizona State University physicist Lawrence Krauss said the 95 percent quoted for climate change is equivalent to the current certainty among physicists that the universe is 13.8 billion years old.

That cigarettes are bad for you?

The president of the prestigious National Academy of Sciences, Ralph Cicerone, and more than a dozen other scientists contacted by the AP said the 95 percent certainty regarding climate change is most similar to the confidence scientists have in the decades’ worth of evidence that cigarettes are deadly.

The 95% is solid. Continuing to nitpick is just wasting time.