NASA’s Hansen: Earth perilously close to tipping point

“No matter how far you have gone on the wrong road, turn back.”

-Turkish proverb

Photo by Rick Chamberlin

I pledged when I started Climate Chronicle to balance the big picture with the not-so-big-picture. If it seems like there have been more posts about the forest than about the trees so far, that’s because there have been.

Apart from an increase in the number and frequency of storms and floods, and other alarming changes to precipitation patterns in Wisconsin, most of the perceptible effects of climate change haven’t exactly been the kind you might read about in the book of Revelation. The summer of 2009 was a relatively cool one in the Upper Midwest (although most of the rest of the world continued to heat up). Invasive species continue to move in from the south, and our native ticks, mosquitoes and poison ivy are all thriving under warmer temperatures and higher CO2 level. But the Four Horsemen of the Apocalypse these things are not.

Of course no one wants climate change to be worse, but let’s face it: if things appeared worse, those of us convinced of the reality of anthropogenic global warming and the threat it represents to every person on the planet would have a much easier time convincing leaders to take the sweeping action necessary to avert disaster. Most people don’t believe something unless they experience it or see it (never mind for a minute the people who won’t see, of which there are many) and they don’t tend to spring to action — at least not en masse — unless presented with evidence (perceived or real) of an emergency.

Climatologist James Hansen thinks the reason things don’t appear worse to most people has to do with the nature of tipping points.

I’m a little late in reading Hansen’s book. After the gut punches contained in Bill McKibben’s Eaarth, I needed some time to catch my breath and get a grip. But I’m sorry I waited so long. In Storms of My Grandchildren: The Truth About the Coming Global Catastrophe and Our Last Chance to Save Humanity, Hansen addresses the matter of perception versus reality on the very first page: “How can we be on the precipice of such consequences [global climate catastrophe] while local climate change remains small compared with day-to-day weather fluctuations?”

Tipping points, Hansen reminds readers, are those places where things can go from stable to unstable very quickly. If you’ve ever been in a small boat or raised children (or been in a small boat with children) you understand tipping points. Like a boat, the planet we inhabit is inherently good at remaining stable, even in nasty weather. But all boats — and all planets — have a tipping point past which things go from relatively OK to gawdawful in the blink of an eye. Before you know what hit you, you’re upside-down and sucking water.

Hansen uses a different analogy to describe amplifying feedbacks, the physical mechanisms that have brought the planet so close to a catastrophic tipping point. It’s like, he says, “when a microphone is placed too close to a speaker, which amplifies any little sound picked up the by the microphone, which then picks up the amplification, which is again picked up by the speaker, until very quickly the noise becomes unbearable.” Example: melting permafrost in the Arctic releases tremendous amounts of methane, a greenhouse gas 22 times more effective than CO2 at trapping heat in the atmosphere, which in turn increases the rate at which the permafrost melts, which releases even more methane, which … you get the idea.

Hansen is considered by many to be the world’s leading climatologist, and his decades of research have convinced him that the planet will become unbearable very soon if we don’t act swiftly and strategically to curb our greenhouse gas emissions. Hansen is best known for bringing global warming to the world’s attention in the 1980s when then Senator Al Gore asked him to testify to Congress. Since 1981 Hansen has been the director of the NASA Goddard Institute for Space Studies, and he is now also an adjunct professor in the Department of Earth and Environmental Sciences at Columbia University and at Columbia’s Earth Institute. He is the reason the climate action group bears the name (or number) it does; it was his research that showed our planet cannot long maintain its climatic and ecological equilibrium beyond 350 parts per million of carbon dioxide in the atmosphere.

Storms of my Grandchildren is an uneven narrative. Although a brilliant scientist, Hansen is not a master storyteller. But he does make several things crystal clear:

1. We have pushed the Earth perilously close to several of those ecological tipping points. Hansen demonstrates this in painstaking, and often painful, detail. But the important thing to remember about those tipping points, which could explosively accelerate warming and sea level rise beyond our ability to effectively mitigate or adapt, is that they are driven by feedbacks that include Antarctic and Greenland ice sheet collapse and submarine methane releases. Every period of great warming and sea level rise in the Earth’s history (and there have been many of them) has been driven by CO2 increases, but it’s the subsequent feedbacks that have pushed the climate past the tipping point and resulted in extremely rapid sea level rise and species extinction. The rates of ice sheet disintegration and methane release have already exceeded many scientists’ expectations.

2. There really still is reason to hope we can stabilize the climate. The science shows that a clear and definite window exists in which to begin to turn things around. That window is small: we have about 20 years — starting now — to phase out coal burning completely and cut our use of oil and other fossil fuels. This will allow us to bring the atmospheric concentration of CO2 back below the crucial threshold of 350 parts per million. Governments are starting to grasp the enormous cost of doing business as usual, but the power of corporate special interests is great.

3. Coal must go — and fast. Hansen is blunt because the physics and the chemistry are blunt and uncompromising: “Coal emissions must be phased out as rapidly as possible or global climate disasters will be a dead certainty.” Coal is the most carbon intense of all the fossil fuels. It’s also the dirtiest, releasing huge quantities of particulates and noxious gasses when burned. The sooty particles or black carbon settles into ice sheets and makes them melt faster. Coal is plentiful compared with its fossil brethren, which means it’s very attractive to those concerned with short-term profits. Everyone is focused on reducing oil right now because there are millions of barrels of it floating around in the Gulf of Mexico and coating wildlife, marshes and beaches, but Hansen points out that reducing the amount of oil we burn, while important, is simply not enough because it will drive down the price and encourage others to burn even more of it. The focus has to be on coal. A large coal-fired power plant like the Columbia generating station in Portage can burn as much as 100 railroad cars of coal in a day. Hansen calls such trains death trains because they feed the power plants that are warming the earth and driving thousands of species to extinction. A conservative estimate is that by the end of the century we will have committed at least 20 percent of the Earth’s species to extinction. Coal is a huge contributor to the air pollution that causes more than one million human deaths per year. That’s one million deaths. Every year. Coal is, quite simply, killing us and the planet we know.

4. Oil sands, tar sands, oil shale and methane hydrates must stay in the ground. These unconventional fossil fuels are just as dirty as coal and must be left where they are. According to Hansen, a barrel of oil made from tar sands produces two to three times more CO2 than conventional oil. Already one pipeline carries Canadian tar sands oil into Wisconsin, where it is refined at the Murphy Oil  refinery in Superior. Murphy Oil has a history of major Clean Air Act violations and spills in Superior and elsewhere. Another refinery near Minneapolis processes tar sands oil into gasoline for Wisconsin. If you fill up at Kwik Trip, you’re burning tar sands oil.

5. Obama may be right after all: nuclear power might need to be part of the solution to the climate crisis. I have always thought nuclear power an abomination. Because of Chernobyl, because the plants are easy targets for terrorists, because they produce waste that remains radioactive for millennia and because some of that waste could be used to produce nuclear weapons. But Hansen points to fast breeder reactors that could run for centuries on the waste already produced by inefficient thermal reactors in operation today, rendering such waste (despite claims to the contrary, such waste can’t be safely stored) harmless within centuries instead of millenia. An added bonus: no uranium mining. The “cooler” waste from breeder reactors cannot be used to make explosive nuclear weapons (it could still be used to make a “dirty” bomb). Hansen writes that the Clinton-Gore administration killed a project to build a demonstration breeder reactor in 1994, largely for political reasons. I used to think breeder reactors a Popular Science fantasy or a nuclear industry ruse, but I may have to modify my position on nuclear power. I’ll definitely be boning up on the technology, because as Hansen makes clear, renewable energy like solar and wind won’t fill the gap left by coal even if we drastically increase energy efficiency.

6. The overall response of the Obama administration and Congress has been woefully inadequate. The terrifying reality of the situation demands sweeping and rapid action. Instead we see incremental-ism and foot dragging in Washington and other capitals around the world. Obama and Congress need to treat this crisis as an imminent threat to our national security. Because it is. Code red.

7. It’s long past time the movement to slow climate change embraced strategic, nonviolent resistance. Hansen writes that he has begun to study Gandhian resistance techniques. When a soft-spoken, conservative scientist from Iowa starts talking this way, you know the situation is critical. But Hansen insists that we should not abandon traditional democratic channels. The courts, especially, hold great promise because they are not as susceptible to the influence of the fossil fuel lobby. Largely through legal action, Bruce Nilles and his team at the Sierra Club’s Beyond Coal campaign have helped stop the construction of more than 100 new coal-fired power plants in the country. But it may be that we will soon have to put our bodies between the death trains and existing coal-fired plants.

As I’ve written elsewhere, public opinion can reach a tipping point, too. It can snowball. But I doubt that can happen fast enough to prevent the kinds of catastrophic climate tipping points Hansen is talking about without political feedbacks that can only be brought about by strategic, nonviolent direct action.



  1. I am afraid what Hansen is saying is that we can possible avert the worst…however, there is bad to come.

  2. Good post! I completely agree. Nobody can know the details of the climate change that’s in progress, but Hansen’s summary is probably as close as you can get, and it’s a very useful foundation for action.

    Humans just aren’t wired to make decisions based on the long view, and definitely not on the very long view. Courts are one of the few venues for making quick (relatively speaking) changes in how we use energy and pollute.

    We need to put our efforts into those avenues that will make the most impact, and stopping coal burning and wood burning (cropland clearing and cooking fires, primarily) are at the top of the list. Breeder reactors have good upside, and I think there are reliable ways of keeping them from producing nuclear weapons fuel now.

    My belief is that solar is the best energy source. It’s falling all over the earth anyway, we spend lots of fossil fuel combating it (air conditioning), and there’s no CO2, no added heat, and no particulates.

  3. Excellent essay. People are woefully short-sighted. The sudden arrival of a tipping point would wake up some folks, but too late to apply a remedy. I had been hoping that the increased damage caused by storms, tornadoes and floods would cause an attention-getting rise in property insurance premiums, to the point where most people would find insurance unaffordable. That might help make global warming real for a complacent populace.

  4. Your comments make a terrific corollary to the post. Solar holds great potential, indeed. For you and other readers who may be interested, here’s a link to some breaking news on research out of Stanford showing that soot from those cooking fires and cleared forests you mention (and diesel engines and coal burning) has a much greater effect on melting ice and global warming than previously thought:

  5. This recent article from National Geographic News gives a good overview of Integral Fast Reactor (IFR) technology and some of the potential advantages and drawbacks: