Stephen Hawking & Carl Sagan on Global Warming: Now 400 PPM and Counting

by Duane Nichols on May 27, 2013

2013: CO2 reaches 400 ppm!

The “Hell” of Venus: A Valuable Reminder To Take the Increasing Greenhouse Effect on Earth Seriously

Why is there any doubt about climate change any more? The depth and width of the scientific consensus is not in doubt, Christopher Monckton et al notwithstanding. The video below is from Climate Crock of the Week and features renowned theoretical physicist Stephen Hawking and the late Carl Sagan, astrophysicist who was David Duncan Professor of Astronomy and Space Sciences and Director of the Laboratory for Planetary Studies at Cornell University. In a posthumous award, Dr. Sagan was awarded the National Science Foundation’s highest award, in recognition that his “research transformed planetary science… his gifts to mankind were infinite.”

Some of what Dr. Hawking says is:

…One of the most serious consequences of our actions is global warming brought about by rising levels of CO2 from the burning of fossil fuels. The danger is that the temperature increase may become self-sustaining, if it hasn’t done so already. Drought and deforestation are reducing the amount of carbon dioxide recycled into the atmosphere and the warming of the seas may trigger the release of large quantities of carbon dioxide trapped on the ocean floor. In addition the melting of the Arctic and Antarctic ice sheets will reduce the amount of solar energy reflected back into space and so increase the temperature further. We don’t know where global warming will stop but the worst case scenario is that the earth will become like its sister planet Venus, with a temperature of 250 degrees C and rain sulphuric acid. The human race could not survive in those conditions.”

Dr. Sagan’s clips also compare the earth and her sister planet, Venus:

“The reason Venus is like a hell seems to be what is called the greenhouse effect…The greenhouse effect can make an earth-like world into a planetary inferno…the hell of Venus is in stark contrast to the comparative heaven of its neighbouring world, our little planetary home, the earth….Carbon dioxide and water vapour make a modest greenhouse effect without which, our oceans would be frozen solid. A little greenhouse effect is a good thing. But Venus is an ominous reminder that in a world rather like the earth, things can go wrong. There is no guarantee that our planet will always be so hospitable. To maintain this clement world we must understand it and appreciate it. The runaway greenhouse effect on Venus is a valuable reminder that we should take the increasing greenhouse effect on earth seriously.”

And here’s another YouTube video featuring Dr. Sagan in his TV series Cosmos (Episode 4 – “Heaven and Hell”), from 1990 – we’ve had twenty three years more to burn fossil fuels and produce other greenhouse gases with our unsustainable way of life:

More links:

Stephen Hawking Warns About Warming

The Global Warming Christmas Special (on SNL) – features Dr. Sagan, Mike Meyers, Tom Hanks, and Ralph Nader

The Carl Sagan Portal

{ 2 comments… read them below or add one }

S. Thomas Bond May 28, 2013 at 8:01 am

This is a very powerful article.

A great source for those who want to do more research, too.

Stephen Hawking is the most powerful theoretical thinker of this century!

And, Carl Sagan understood the unique place of our race of humanity

In the entire Universe!

Wisdom can have no better Sources than these two!


Myrna September 12, 2015 at 9:17 pm

Pay attention, world.

The politicians will drag their feet until the people demand action.


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