Carl Sagan Quotes

It is a fact that, up to seven million people a year are dying from fossil fuel pollution. It is a fact that we are already dealing with the catastrophe of climate change in places like California, where people have been burnt out of their homes and where they are dealing with record droughts.

We must recognize that we're all part of a web of life around the world. Anytime you extinguish a species, the consequences are serious.

I came back out here from England and I was there for a while and it was beautiful and it is just great to see London going from Spring to Summer and Autumn.

The U.N.'s current projection is that humanity will number 9.3 billion individuals in 2050 and then hit 10.1 billion by 2100. Meanwhile, our energy resources are dwindling, and droughts threaten our food supplies.

Hurricane Katrina this past week was certainly the worst episode in what has become an all-too-familiar and tragic cycle, and our nation is now faced with a set of unprecedented challenges.

The floods and fires and storms and droughts that Australia has suffered in the last few years have left no doubt in many Australians' minds about just how much is a stake in a super-heated world.

Fracking kills, and it doesn't just kill us. It kills the land, nature and, eventually, the whole world.

War contributes greatly to global warming, which shouldn't surprise us. All those bombs going off, all those rockets, all those planes and helicopters. All that fuel of various kinds being used. It pollutes the air and water of this very fragile and interconnected planet.

I may like L.A., but I want to know when the seasons are.

Man is complex—he makes deserts bloom and lakes die.

Local conflicts can have global consequences.

All countries will feel the increasing effects of dangerous climate change and it is those least able to bear it who are already being hurt first and hardest.

The season is very long.

What is the future going to say about us now? What are our kids going to look at us and say, 'How could you not stop that person from getting into power? How could you not stop that environmental disaster that you saw coming a mile away?'

We'd already lost the possibility of stopping global warming entirely. That hasn't been in the cards for a long time. The triumph of Trump probably means that we're not going to be able to stop it at the two-degree mark that the world had been aiming for. That's very bad news, mostly because the planet seems to be more sensitive than we thought to even small increases in temperature.

Once the steam engine went away and we started moving into burning fossil fuels - not just burning them, but everything we do with oil - we've been experiencing [these problems] at an accelerated rate. The scary end-game scenario is getting closer and closer, about what we're going to be able to do to sustain life on this planet as we have come to know it. And I think this is a very real possibility, that we could be dealing with conditions we have no idea how to wrestle with.

Unless we stop dumping 70 million tons of global warming pollution into the atmosphere every 24 hours, which we are doing right now ... the continued acceleration of this pollution would destroy the future of human civilization.

I will not sleep fine if Donald Trump wins and I will not sleep fine is Hillary Clinton wins. Whether you are looking at nuclear weapons, whether you are looking at expanding wars and their blowback, which will not stop as long as those wars continue to expand, or whether you're looking at the climate, in my view, we have no choice. This is an existential moment. We are deciding not only what kind of world we will have, but whether we will have a world or not. I think it's very important to get outside this box that tells us we are powerless, when in fact, we are powerful.

Before the war, and especially before the Boer War, it was summer all the year round.

We will pay for this [climate change] one way or another. We will pay to reduce greenhouse-gas emissions today and we'll have to take an enormous hit of some kind. Or we will pay the price later in military terms. And that will involve human lives. There will be a human toll. There is no way out of this that does not have real costs attached to it.

Climate change is a result of the greatest market failure the world has seen...We risk damages on a scale larger than the two world wars of the last century.

The world's deteriorating ecology poses as great a danger to mankind today as did the nuclear standoff between the superpowers at the height of the Cold War.

Our next Cold War ought to be with ourselves...After all, who poses the biggest danger to the American environment? We do.

Humans may be destroying their chances for decent survival. It won't kill everybody, but it would change the world dramatically.

A third of summer sea ice in the Arctic is gone, the oceans are 30 percent more acidic, and since warm air holds more water vapor than cold, the atmosphere over the oceans is a shocking five percent wetter, loading the dice for devastating floods.