Sunday, August 5, 2012

Proving the obvious

The central skill of science is precise observation.  Unfortunately, observation tells us what is—not necessarily what will happen in the future.  Which is why when computer modeling became possible, everyone jumped on that bandwagon.  Like all forms of modeling, it's a lot harder than it looks—and it looks damn hard.  So, not surprisingly, mathematical models of pretty much anything have not lived up to the high expectations we all had back when we still carted around the punch cards used to communicate with computers.  And in some disciplines such as economics, the reliance on models has been catastrophic.

I might suggest that reliance on mathematical models in the climate change "debates" has been almost as disastrous as with economics—even though climate modeling uses more relevant data and employs more hard science disciplines like chemistry and fluid dynamics.  And it did not need to happen.  The basic climate change argument is fifth-grade simple—all our fires have led to more carbon dioxide in the atmosphere.  CO2 traps solar energy more efficiently than nitrogen and oxygen.  Therefore, our atmosphere now has more energy.  This means our hot days will be hotter, our windy days windier, our droughts drier, etc.  This is what we know—all other predictions are educated guesses.

But we have gone past the point where predictions are necessary.  Now we can go simply with observations.  Some day, maybe soon, our ability to predict the effects of climate change will get a lot better.  Why not?—the ability to predict weather events has been transformed in my lifetime from a barometer, a thermometer, and watching the sky to the other night when I watched a thunderstorm march through my county on Nexrad streamed to an iPad.  Of course, weather forecasting got better through better methods of observation (satellite images, doppler radar, etc.) and NOT through modeling—which is still in its infancy.

So I am delighted to see that James Hansen has decided that climate change is by now so freaking obvious to anyone who looks out his front door, that we can better describe the phenomenon using historical records and statistical analysis than by arguing which flawed math model is more valid.

Climate Change Study Ties Recent Heat Waves To Global Warming


WASHINGTON — The relentless, weather-gone-crazy type of heat that has blistered the United States and other parts of the world in recent years is so rare that it can't be anything but man-made global warming, says a new statistical analysis from a top government scientist.

The research by a man often called the "godfather of global warming" says that the likelihood of such temperatures occurring from the 1950s through the 1980s was rarer than 1 in 300. Now, the odds are closer to 1 in 10, according to the study by NASA scientist James Hansen. He says that statistically what's happening is not random or normal, but pure and simple climate change.

"This is not some scientific theory. We are now experiencing scientific fact," Hansen told The Associated Press in an interview.

Hansen is a scientist at NASA's Goddard Institute for Space Studies in New York and a professor at Columbia University. But he is also a strident activist who has called for government action to curb greenhouse gases for years. While his study was published online Saturday in the Proceedings of the National Academy of Science, it is unlikely to sway opinion among the remaining climate change skeptics.

However, several climate scientists praised the new work.

In a blunt departure from most climate research, Hansen's study – based on statistics, not the more typical climate modeling – blames these three heat waves purely on global warming:
  • Last year's devastating Texas-Oklahoma drought.
  • The 2010 heat waves in Russia and the Middle East, which led to thousands of deaths.
  • The 2003 European heat wave blamed for tens of thousands of deaths, especially among the elderly in France.
The analysis was written before the current drought and record-breaking temperatures that have seared much of the United States this year. But Hansen believes this too is another prime example of global warming at its worst.

The new research makes the case for the severity of global warming in a different way than most scientific studies and uses simple math instead of relying on complex climate models or an understanding of atmospheric physics. It also doesn't bother with the usual caveats about individual weather events having numerous causes.

The increase in the chance of extreme heat, drought and heavy downpours in certain regions is so huge that scientists should stop hemming and hawing, Hansen said. "This is happening often enough, over a big enough area that people can see it happening," he said.

Scientists have generally responded that it's impossible to say whether single events are caused by global warming, because of the influence of natural weather variability.

However, that position has been shifting in recent months, as other studies too have concluded climate change is happening right before our eyes.

Hansen hopes his new study will shift people's thinking about climate change and goad governments into action. He wrote an op-ed piece that appeared online Friday in the Washington Post.

"There is still time to act and avoid a worsening climate, but we are wasting precious time," he wrote.

The science in Hansen's study is excellent "and reframes the question," said Andrew Weaver, a climate scientist at the University of Victoria in British Columbia who was a member of the Nobel Prize-winning international panel of climate scientists that issued a series of reports on global warming.

"Rather than say, `Is this because of climate change?' That's the wrong question. What you can say is, `How likely is this to have occurred with the absence of global warming?' It's so extraordinarily unlikely that it has to be due to global warming," Weaver said.  more
For the record, this is how Hansen begins his WaPo OpEd.  See also this article from Think Progress that delves more deeply into Hansen's new line of reasoning.

“Climate Change Is Here — And Worse Than We Thought”

When I testified before the Senate in the hot summer of 1988 , I warned of the kind of future that climate change would bring to us and our planet. I painted a grim picture of the consequences of steadily increasing temperatures, driven by mankind’s use of fossil fuels.

But I have a confession to make: I was too optimistic.

My projections about increasing global temperature have been proved true. But I failed to fully explore how quickly that average rise would drive an increase in extreme weather.

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. more

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