James Hansen Quotes

The basic science is very well established; it is well understood that global warming is due to greenhouse gases. What is uncertain is projections about specifics in the next few decades, by how much will the climate change.

I will defend the NASA Earth Science Division with everything I've got.

Climate change is not the fault of man. It's Mother Nature's way. And sucking greenhouse gases from the atmosphere is too limited a solution. We have to be prepared for fire or ice, for fry or freeze. We have to be prepared for change.

Climate is always evolving, and natural disaster have always existed.

The basic scientific conclusions on climate change are very robust and for good reason. The greenhouse effect is simple science: greenhouse gases trap heat, and humans are emitting ever more greenhouse gases.

The science is clear that there is an increase in the amount of CO2 in the atmosphere. What is not clear from the science is how much of that increase is caused by human activity; and what also is not clear is what impact those increases have on the climatic cycle.

Many of the issues we face in dealing with rapid climate change are well suited to an engineering mind.

Some people call it global warming; some people call it climate change. What is the difference?

One thing most people would agree is that climate change would add further uncertainties to our already quite tight water supply situation in China.

One volcano puts out more toxic gases - one volcano - than man makes in a whole year. And when you look at this 'climate change,' and when you look at the regular climate change that we all have in the world, we have warm and we have cooling spells.

Believe it or not, very little research has ever been funded to search for natural mechanisms of warming... it has simply been assumed that global warming is manmade. Climate change - it happens, with or without our help.

You can't say for certain what will happen to the weather in the long term.

I think there is a degree of speculation that is satisfied the climate is changing.

Climate does fluctuate. It goes from hot to cold. We have ice ages.

However useful computer models may be, the one thing they cannot be is evidence. Computer climate models are simply conjectures.

Prime Minister Cameron says he wants to be the greenest government ever, but the definition of green is immature... I don't deny for a moment that CO2 is a greenhouse gas, but there are so many other factors that affect climate. It is more complicated than the computer models that we are using. What the truth is, nobody knows.

Our climate is always changing.

If we gutted NASA Earth Science, it wouldn't be NOAA or some other agency that would take the lead. It would be the Chinese and the Europeans and the Japanese.

The climate is changing; I don't think you can deny that. But climate has always changed.

Through space-based climate studies, my colleagues and I have learned that a stable and comfortable climate is not something to take for granted.

They're not predicting global warming based on what's happened in the past; they're basing it on what their computer predictions say, and nothing more.

We see something change in our climate and we blame ourselves ... I don't think we understand what happens. We can watch it happen on the (climate) models, we know it happens, but we don't know for sure how it happens.

I believe the climate is changing.

If every country's climate policy was driven purely by environmental science, we may have no need for international agreements.

Climate change is the environmental challenge of this generation, and it is imperative that we act before it's too late.