James Hansen quotes:

  • Recent warming coincides with rapid growth of human-made greenhouse gases. The observed rapid warming gives urgency to discussions about how to slow greenhouse gas emissions.

  • We have known since the 1800s that carbon dioxide traps heat in the atmosphere. The right amount keeps the climate conducive to human life.

  • Money has too big an influence on our politics in Washington and somehow we need to do something about that.

  • CEOs of fossil energy companies know what they are doing and are aware of long-term consequences of continued business as usual. In my opinion, these CEOs should be tried for high crimes against humanity and nature.

  • If your child gets asthma, the fossil fuel industry doesn't pay. Or if there's a natural disaster, the bill is paid by the taxpayer, not the fossil fuel company.

  • Because cap and trade is enforced through the selling and trading of permits, it actually perpetuates the pollution it is supposed to eliminate.

  • On a per capita basis, Britain is responsible for more of the carbon dioxide now in the atmosphere than any other nation on Earth because it has been burning it from the dawn of the Industrial Revolution.

  • Coral reefs, the rain forest of the ocean, are home for one-third of the species of the sea. Coral reefs are under stress for several reasons, including warming of the ocean, but especially because of ocean acidification, a direct effect of added carbon dioxide. Ocean life dependent on carbonate shells and skeletons is threatened by dissolution as the ocean becomes more acid.

  • Several times in Earth's history, rapid global warming occurred, apparently spurred by amplifying feedbacks. In each case, more than half of plant and animal species became extinct. New species came into being over tens and hundreds of thousands of years. But these are time scales and generations that we cannot imagine.

  • The democratic process is supposed to be one person one vote, but it turns out that money is talking louder than the votes.

  • Tipping points are so dangerous because if you pass them, the climate is out of humanity's control: if an ice sheet disintegrates and starts to slide into the ocean there's nothing we can do about that.

  • We have to, in the next ten years, begin to decrease the rate of carbon dioxide emissions and then flatten it out. If that doesn't happen in ten years, we're going to be passing certain tipping points. If the ice sheets begin to disintegrate, what can you do about it? You can't tie a rope around an ice sheet.

  • As a government employee, you can't testify against the government.

  • Until the public demands otherwise, the policy makers will continue to serve their financiers.

  • ...chief executives of large fossil fuel companies to [should] be put on trial for high crimes against humanity and nature; [Hansen] accusing them of actively spreading doubt about global warming in the same way that tobacco companies blurred the links between smoking and cancer.

  • I tend to be naive and gullible, I guess, but I try to believe that governments believe what they say.

  • I have been described as the grandfather of climate change. In fact, I am just a grandfather and I do not want my grandchildren to say that grandpa understood what was happening but didn't make it clear.

  • We need to send a message to Congress and the president that we want them to take the actions that are needed to preserve climate for young people and future generations and all life on the planet.

  • The carbon emissions from tar shale and tar sands would initiate a continual unfolding of climate disasters over the course of this century. We would be miserable stewards of creation. We would rob our own children and grandchildren.

  • The climate dice are now loaded. Some seasons still will be cooler than the long-term average, but the perceptive person should notice that the frequency of unusually warm extremes is increasing. It is the extremes that have the most impact on people and other life on the planet.

  • The fact is fossil fuel carbon will stay in the surface climate system for millennia.

  • What we are doing to the future of our children, and the other species on the planet, is a clear moral issue.

  • The five warmest years over the last century occurred in the last eight years.

  • The trains carrying coal to power plants are death trains. Coal-fired power plants are factories of death."

  • We have known since the 1800s that carbon dioxide traps heat in the atmosphere. The right amount keeps the climate conducive to human life."

  • After spending three or four years interacting with the Bush administration, I realized they were not taking any actions to deal with climate change. So, I decided to give one talk, and then it snowballed into another talk and eventually to even protesting and getting arrested.

  • Imagine a giant asteroid on a direct collision course with Earth. That is the equivalent of what we face now [with climate change], yet we dither.

  • There is still time to act and avoid a worsening climate, but we are wasting precious time,

  • We're running out of time.

  • The fact is fossil fuel carbon will stay in the surface climate system for millennia."

  • With a fourth generation of nuclear power, you can have a technology that will burn more than 99 percent of the energy in the fuel. It would mean that you don't need to mine uranium for the next thousand years.

  • I was lucky to grow up at a time when it was not difficult for the child of a tenant farmer to make his way to the state university.

  • Planet Earth, creation, the world in which civilization developed, the world with climate patterns that we know and stable shorelines, is in imminent peril.

  • We're handing them [young people & future generations] a climate system which is potentially out of their control. We're in an emergency: you can see what's on the horizon over the next few decades with the effects it will have on ecosystems, sea level and species extinction

  • It would be immoral to leave young people with a climate system spiraling out of control.

  • The five-year mean global temperature has been flat for the last decade

  • A level of no more than 350 ppm is still feasible, with the help of reforestation and improved agricultural practices, but just barely - time is running out.

  • We are on the precipice of climate system tipping points beyond which there is no redemption.

  • The trains carrying coal to power plants are death trains. Coal-fired power plants are factories of death.

  • I think we have a very brief window of opportunity to deal with climate change... no longer than a decade, at the most.

  • Consider the perverse effect cap and trade has on altruistic actions. Say you decide to buy a small, high-efficiency car. That reduces your emissions, but not your country's. Instead it allows somebody else to buy a bigger S.U.V. - because the total emissions are set by the cap.

  • Climate change is analogous to Lincoln and slavery or Churchill and Nazism: it's not the kind of thing where you can compromise.

  • Coal is responsible for as much atmospheric carbon dioxide as other fossil fuels combined and it still has far greater reserves. We must stop using it.

  • Adding CO2 to the air is like throwing another blanket on the bed.

  • What makes tar sands particularly odious is that the energy you get out in the end, per unit carbon dioxide, is poor. It's equivalent to burning coal in your automobile.

  • It's as certain that as long as fossil fuels are the cheapest energy, we will just keep burning them.

  • The United States did not sign Kyoto, yet its emissions are not that different from the countries that did sign it.

  • Jail threats did not dissuade Martin Luther King - and intergenerational justice is a moral issue of comparable magnitude to civil rights.

  • As species are exterminated by shifting climate zones, ecosystems can collapse, destroying more species.

  • Global warming isn't a prediction. It is happening.

  • You can't turn on your television without seeing these advertisements about clean coal, clean tar sands and the claim that there's more jobs associated with fossil fuels than other industries. That's of course not true. But they're hammering that into the voters' heads.

  • Being at NASA and having the access to both computing capability and satellite observation capability is kind of the ideal research situation to try to understand global climate change.

  • Talking nice about sun and wind and green jobs is just greenwash.

  • If we fail to act, we will end up with a different planet.

  • Politicians think that if matters look difficult, compromise is a good approach. Unfortunately, nature and the laws of physics cannot compromise - they are what they are.

  • How long have we got? We have to stabilize emissions of carbon dioxide within a decade, or temperatures will warm by more than one degree... We don't have much time left.

  • The climate system is being pushed hard enough that change will become obvious to the man in the street in the next decade.

  • Only in the last few years did the science crystallize, revealing the urgency - our planet really is in peril. If we do not change course soon, we will hand our children a situation that is out of their control.

  • Global warming has already triggered a sea level rise that could reach from 6 metres (19.69 ft) to 25 metres (27.34 yards).

  • The five-year mean global temperature has been flat for the last decade, which we interpret as a combination of natural variability and a slow down in the growth rate of net climate forcing.

  • The evidence for human-made climate change is overwhelming.

  • The forcings that drive long-term climate change are not known with an accuracy sufficient to define future climate change.

  • Interference with communications of science to the public has been greater during the current administration than at any time in my career,

  • The last time the world was three degrees warmer than today-which is what we expect later this century-sea levels were 25m higher. So that is what we can look forward to if we don't act soon.

  • ...the global surface albedo [surface whiteness] and greenhouse gas changes account for practically the entire global climate change.

  • The question is not whether to close the parks, but how to accomplish this goal.

  • Cap and trade generates special interests, lobbyists, and trading schemes, yielding non-productive millionaires, all at public expense. The public is fed up with such business. Tax with 100% dividend, in contrast, would spur our economy, while aiding the disadvantaged, the climate, and our national security.

  • Rising carbon price is essential to 'decarbonize' the economy - to remove the nation towards the era beyond fossil fuels.

  • In view of the immense power of natural weather and climate fluctuations and the great buffering capacity of the Earth, especially the ocean, it is easy to be skeptical about whether small anthropogenic changes of atmospheric composition can have important practical impacts.

  • What has become clear from the science is that we cannot burn all of the fossil fuels without creating a very different planet.

  • If we drive our fellow species to extinction, we will leave a far more desolate planet for our descendants than the world we inherited from our elders.

  • Some Democrats deserve to be criticized.

  • We have at most ten years"?not ten years to decide upon action, but ten years to alter fundamentally the trajectory of global greenhouse emissions.

  • I've tried to be a straight scientist doing the science and reporting it as best I can.

  • As you get more global warming, you should see an increase in the extremes of the hydrological cycle - droughts and floods and heavy precipitation.

  • It has become very difficult for anyone to argue that observed global warming is natural variability. We have good reason for being able to say that the world will be warmer by about a quarter of a degree in the next decade. It's the same reason we had 10 years ago when we said that the 1990s would be warmer than the 1980s: The planet is out of equilibrium.

  • The urgency derives from the nearness of climate tipping points.

  • We cannot afford to put off change any longer. We have to get on a new path within this new administration. We have only four years left for Obama to set an example to the rest of the world. America must take the lead.

  • Policy decisions on climate change are being deliberated every day by those without full knowledge of the science, and often with intentional misinformation spawned by special interests.

  • ...99 percent confident that the world really was getting warmer and that there was a high degree of probability that it was due to human-made greenhouse gases.

  • Burning all the fossil fuels will destroy the planet we know, Creation, the planet of stable climate in which civilization developed.

  • The greatest danger hanging over our children and grandchildren is initiation of changes that will be irreversible on any time scale that humans can imagine.

  • The climate is nearing tipping points. Changes are beginning to appear and there is a potential for explosive changes, effects that would be irreversible, if we do not rapidly slow fossil-fuel emissions over the next few decades.

  • Scientists will say we can't blame global warming for any single event. In a sense that's right, but the fact that the frequency and intensity of these events is increasing you can blame on global warming.

  • 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 [2011] can each be attributed to 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.

  • Well, you know what happens to crime when the heat goes up.

  • Injection of environmental and political perspectives in midstream of the science discussion cannot help the process of inquiry. I believe that persons with relevant scientific expertise should concentrate, with pride, on cool objective analysis, providing information to the public and decision-makers when it is found, but leaving the moral implications for later common consideration, or at most for summary inferential discussion.

  • The scientific excitement in comparing theory with data, and developing some understanding of global changes that are occurring, is what makes all the other stuff worth it.

  • We have at most ten years - not ten years to decide upon action, but ten years to alter fundamentally the trajectory of global greenhouse emissions... We are near a tipping point, a point of no return, beyond which the built in momentum and feedbacks will carry us to levels of climate change with staggering consequences for humanity and all of the residents of this planet.

  • The danger is that the compromises and special interests inherent in Kyoto-style targets and cap-and-trade will be accepted because of bureaucratic momentum.

  • Goals and caps on carbon emissions are practically worthless, if coal emissions continue, because of the exceedingly long lifetime of carbon dioxide in the air.

  • Coal is the single greatest threat to civilization and all life on our planet.