Thursday, January 12, 2017

Rolling Stone:  Will We Miss Our Last Chance to Save the World From Climate Change?

"The energy system and the tax system have got to be simplified in a way that everybody understands and doesn’t allow the wealthy few to completely rig the system," says Hansen.  (Credit: Benedict Evans/Redux) Click to Enlarge.
In the late 1980s, James Hansen became the first scientist to offer unassailable evidence that burning fossil fuels is heating up the planet.  In the decades since, as the world has warmed, the ice has melted and the wildfires have spread, he has published papers on everything from the risks of rapid sea-level rise to the role of soot in global temperature changes – all of it highlighting, methodically and verifiably, that our fossil-fuel-powered civilization is a suicide machine.  And unlike some scientists, Hansen was never content to hide in his office at NASA, where he was head of the Goddard Institute for Space Studies in New York for nearly 35 years.  He has testified before Congress, marched in rallies, and participated in protests against the Keystone XL Pipeline and Big Coal (he went so far as to call coal trains "death trains").
The enormity of Hansen's insights, and the need to take immediate action, have never been clearer.  In November, temperatures in the Arctic, where ice coverage is already at historic lows, hit 36 degrees above average – a spike that freaked out even the most jaded climate scientists.  At the same time, alarming new evidence suggests the giant ice sheets of West Antarctica are growing increasingly unstable, elevating the risk of rapid sea-level rise that could have catastrophic consequences for cities around the world.  Not to mention that in September, average measurements of carbon dioxide in the atmosphere hit a record 400 parts per million.  And of course, at precisely this crucial moment – a moment when the leaders of the world's biggest economies had just signed a new treaty to cut carbon pollution in the coming decades – the second-largest emitter of greenhouse gases on the planet elected a president who thinks climate change is a hoax cooked up by the Chinese.

Hansen, 75, retired from NASA in 2013, but he remains as active and outspoken as ever. To avoid the worst impacts of climate change, he argues, sweeping changes in energy and politics are needed, including investments in new nuclear technology, a carbon tax on fossil fuels, and perhaps a new political party that is free of corporate interests.

He is also deeply involved in a lawsuit against the federal government, brought by 21 kids under the age of 21 (including Hansen's granddaughter), which argues that politicians knowingly allowed big polluters to wreck the Earth's atmosphere and imperil the future well-being of young people in America.  A few weeks ago, a federal district judge in Oregon delivered an opinion that found a stable climate is indeed a fundamental right, clearing the way for the case to go to trial in 2017.  Hansen, who believes that the American political system is too corrupt to deal with climate change through traditional legislation, was hopeful.  "It could be as important for climate as the Civil Rights Act was for discrimination," he told me.
How would you judge President Obama's legacy on climate change?

I would give him a D.  You know, he's saying the right words, but he had a golden opportunity.  When he had control of both houses of Congress and a 70 percent approval rating, he could have done something strong on climate in the first term – but he would have had to be a different personality than he is.  He would have to have taken the FDR approach of explaining things to the American public with his "fireside chats," and he would have had to work with Congress, which he didn't do.

You know, the liberal approach of subsidizing solar panels and windmills gets you a few percent of the energy, but it doesn't phase you off fossil fuels, and it never will.  No matter how much you subsidize them, intermittent renewables are not sufficient to replace fossil fuels.  So he did a few things that were useful, but it's not the fundamental approach that's needed.

Rolling Stones - by James Hansen

I do few interviews because of the time required and my difficulty in making things clear orally.  The Rolling Stone interview by Jeff Goodell was an exception, a testimony to his abilities.

An important number in the story was not right, but is being corrected.  It made me wonder how to make that number simple enough for people (including ourselves) to remember easily.

The number is the amount of carbon that we must somehow suck out of the air, if we want to get back to 350 ppm CO2 in the air by the end of the century, which is a first approximation, a first target, for what must be done to keep climate close to the Holocene range, the relatively stable climate of the past 11,700 years during which civilization developed.

You may say, well that’s a stiff requirement, so let’s just allow climate to be hotter.  But that would mean you are willing to accept a continually receding shoreline, with eventual loss of all coastal cities.  When that would happen is debatable – an inherently difficult nonlinear problem – but each new piece of evidence is pushing it sooner than the experts had been estimating.  And remember that coastal cities include more than half of the world’s large cities, likely many of the cities you love, with lots of history.  Consider the implied humanitarian and economic debacles, with hundreds of millions of refugees.]

Back to the number: we showed in a 2013 paper that we would need to extract 100 GtC[1] to get back to 350 ppm by 2100, if we began reducing emissions in 2013 at the (optimistic) rate of 6%/year.  100 GtC is almost as large as the net historical emissions from deforestation, so it is about as much as we could hope to extract via improved agricultural and forestry practices.

However, emissions did not begin to decline in 2013.  Emission growth slowed down from about 3%/year in the preceding two decades to an average 0.6%/year in 2012-2015. Because of the time it takes to move politics and to change energy infrastructure, in our newest paper (now under review) we assume that global emissions will change little in the next four years.

If we further assume the same 6%/year emission reduction rate beginning in 2021 relative to 2020, the extraction from the air required to get to 350 ppm by 2100 is ~150 GtC.

So, the bottom line is that the 8-year period (2013-2020) of continued high emissions changes the required CO2 extraction from 100 GtC to 150 GtC – another easy # to remember.

Read more at Rolling Stone:  Will We Miss Our Last Chance to Save the World From Climate Change?

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